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Lifestyle Risk Factors Increase the Risk of Hospitalization for Sciatica: Findings of Four Prospective Cohort Studies
Abstract
BACKGROUND: The purpose of this study is to assess the effects of lifestyle risk factors on the risk of hospitalization
for sciatica and to determine whether overweight or obesity modifies the effect of leisure-time
physical activity on hospitalization for sciatica.
METHODS: We included 4 Finnish prospective cohort studies (Health 2000 Survey, Mobile Clinic Survey,
Helsinki Health Study, and Young Finns Study) consisting of 34,589 participants and 1259 hospitalizations
for sciatica during 12 to 30 years of follow-up. Sciatica was based on hospital discharge register data.
We conducted a random-effects individual participant data meta-analysis.
RESULTS: After adjustment for confounding factors, current smoking at baseline increased the risk of subsequent
hospitalization for sciatica by 33% (95% confidence interval [CI], 13%-56%), whereas past smokers
were no longer at increased risk. Obesity defined by body mass index increased the risk of hospitalization
for sciatica by 36% (95% CI 7%-74%), and abdominal obesity defined by waist circumference increased
the risk by 41% (95% CI 3%-93%).Walking or cycling to work reduced the risk of hospitalization for sciatica
by 33% (95% CI 4%-53%), and the effect was independent of body weight and other leisure activities,
while other types of leisure activities did not have a statistically significant effect.
CONCLUSIONS: Smoking and obesity increase the risk of hospitalization for sciatica, whereas walking or
cycling to work protects against hospitalization for sciatica. Walking and cycling can be recommended for
the prevention of sciatica in the general population.
... Among lifestyle risk factors, smoking (11) and excess body mass (12) increase the risk of transient and chronic LBP as well as health care consultation for LBP. Moreover, smoking (13,14) and overweight/obesity (14,15) increase the risk of lumbar radicular pain and hospitalization for sciatica. The role of leisure-time physical activity in LBP and sciatica is still uncertain. ...
... Among lifestyle risk factors, smoking (11) and excess body mass (12) increase the risk of transient and chronic LBP as well as health care consultation for LBP. Moreover, smoking (13,14) and overweight/obesity (14,15) increase the risk of lumbar radicular pain and hospitalization for sciatica. The role of leisure-time physical activity in LBP and sciatica is still uncertain. ...
... Leisure-time physical activity may reduce the risk of chronic LBP (16) and lumbar radicular pain (10). Recently, we found that walking or cycling to work reduces the risk of hospitalization for sciatica (14). ...
Objective
To identify risk factors for low back pain (LBP) and lumbar radicular pain and to assess whether obesity and exposure to workload factors modify the effect of leisure‐time physical activity on LBP and lumbar radicular pain.
Methods
The population of this 11‐year longitudinal study consists of a nationally representative sample of Finns ages ≥30 years (n = 3,505). The outcomes of the study were LBP and lumbar radicular pain for >7 days or for >30 days in the past 12 months at follow‐up.
Results
LBP and lumbar radicular pain were more common in women than in men. LBP slightly declined with increasing age, while lumbar radicular pain increased with age. Abdominal obesity (defined by waist circumference) increased the risk of LBP (adjusted odds ratio [OR] 1.40 [95% confidence interval (95% CI) 1.16–1.68] for LBP >7 days and adjusted OR 1.41 [95% CI 1.13–1.76] for LBP >30 days) and general obesity (defined by body mass index) increased the risk of lumbar radicular pain (adjusted OR 1.44 [95% CI 1.12–1.85] for pain >7 days and adjusted OR 1.62 [95% CI 1.16–2.26] for pain >30 days). Smoking and strenuous physical work increased the risk of both LBP and lumbar radicular pain. Walking or cycling to work reduced the risk of LBP, particularly LBP for >30 days (adjusted OR 0.75 [95% CI 0.59–0.95]), with the largest reductions among nonabdominally obese individuals and among those not exposed to physical workload factors. Using vibrating tools increased the risk of lumbar radicular pain.
Conclusion
Lifestyle and physical workload factors increase the risk of LBP and lumbar radicular pain. Walking and cycling may have preventive potential for LBP.
... Sub-acute pain is the pain that has been present for 1 to 6 months; moreover, pain becomes classified as chronic at 6 months (Rahimi-Movaghar et al., 2011). The most common cause of sciatica is a herniated lumbar disc with nerve root compression (Shiri et al., 2017). The sacroiliac joint (SIJ) was examined to be the most important cause of sciatica in 1920. ...
... It was found that heavy lifting, occupational workload, injury and depression are the important risk factors for the prevalence of sciatica, which is similar to previously published studies (Leclerc et al., 2003;Peul et al., 2008;Wang et al., 2016;Shiri et al., 2017) et al. (2009) identified smoking as an important risk factor for sciatica. Another interesting point was noted that postmenopausal women (52.2%) showed a higher prevalence of having sciatica. ...
... In line with our findings, prior reviews have concluded that overweight and obesity increase the risk of non-specific LBP, 5 radiating LBP, 31 lumbar radicular pain, 32 and sciatica. 32,33 However, these reviews did not examine the role of obesity as a prognostic factor. Our findings suggest that the role of obesity in recurrent LBP is minor. ...
... Like obesity, smoking has been reported to increase the risk of non-specific LBP, 4 lumbar radicular pain, 34 and sciatica. 33 In these data smoking was neither a risk nor a prognostic factor of LBP. The prevalence of daily smoking in the study population was lower than in the Swedish general population. ...
STUDY DESIGN:
Prospective longitudinal cohort study.
OBJECTIVE:
To determine the associations ofr workload and health-related factors with incident and recurrent low back pain (LBP), and to determine the mediating role of health-related factors in associations between physical workload factors and incident LBP.
SUMMARY OF BACKGROUND DATA:
It is not known whether the risk factors for the development of LBP are also prognostic factors for recurrence of LBP and whether the associations between physical workload and incident LBP are mediated by health-related factors. We used data from the Swedish Longitudinal Occupational Survey of Health (SLOSH) study. Those responding to any two subsequent surveys in 2010-2016 were included for the main analyses (N = 17,962). Information on occupational lifting, working in twisted positions, weight/height, smoking, physical activity, depressive symptoms, and sleep problems were self-reported. Incident LBP was defined as pain limiting daily activities in the preceding three months in participants free from LBP at baseline. Recurrent LBP was defined as having LBP both at baseline and follow-up. For the mediation analyses, those responding to three subsequent surveys were included (N = 3,516).
METHODS:
Main associations were determined using generalized estimating equation models for repeated measures data. Mediation was examined with counterfactual mediation analysis.
RESULTS:
All risk factors at baseline but smoking and physical activity were associated with incident LBP after adjustment for confounders. The strongest associations were observed for working in twisted positions (risk ratio (RR) = 1.52, 95% CI 1.37, 1.70) and occupational lifting (RR = 1.52, 95% CI 1.32, 1.74). These associations were not mediated by health-related factors. The studied factors did not have meaningful effects on recurrent LBP.
CONCLUSIONS:
The findings suggest that workload and health-related factors have stronger effects on the development than on the recurrence or progression of LBP, and that health-related factors do not mediate associations between workload factors and incident LBP.
LEVEL OF EVIDENCE:
3.
... First, Shiri et al. [2] conducted a meta-analysis to assess the effect of lifestyle factors on hospitalization for sciatica by considering obesity and leisure-time physical activity. AHRs (95% CIs) of current smoking and walking/cycling to workplace for sciatica were 1.33 (1.13-1.56) ...
... and 0.67 (0.47-0.96), respectively. Euro et al. [1] conducted a stratified analysis by sex, and Shiri et al. [2] used "sex" as an adjusting variable. Euro et al. [1] recognized overweight as a significant risk factor for hospitalization for sciatica among women, and protective effect of leisure-time physical activity on hospitalization for sciatica was observed among men. ...
... Chronic sciatica pain is a clinical condition with the presence of radiating pain in one leg, with or without the association of neurological problems of weakness in muscle and paraesthesia (Davis et al., 2023). Mostly the pain improves over time with conservative treatment like exercise, manual therapy, and other management therapy (Shiri et al., 2017). Generally a short course treatment of NSAIDs, other opiods and non opiod analgesicis, few muscle relaxants, anti convulsants, antidepressants and localized corticosteroid injections are prescribed but no perfect treatment is available. ...
Sciatica, a debilitating condition arising from sciatic nerve pathology, presents challenges in its management due to its associated symptoms like radiating pain, muscle weakness, and paraesthesia. Current treatments methods often involve conservative approaches, including exercise, manual therapy, and pain management. However, there remains a need for more effective interventions that can alleviate symptoms and improve the overall quality of life for individuals suffering from this condition.Chronic Constriction Injury nerve pain induced rats received vehicle, resveratrol (50mg/kg) alone and with optimized cocrystal technology developed cocrystals of resveratrol (50 mg/kg) orally for 14 days. Thermal allodynia, cold allodynia and mechanical hyperalgesia tests performed to all animals. Blood and nerve tissues were taken for further studies. In chronic constriction injury group significantly damaged the nerve cells, increased oxidative stress and declined reduced glutathione levels observed. Resveratrol reduced these effects, but much improved attenuation of sciatic pain reversal with cellular damage was resulted with cocrystals of resveratrol. The bioavailability increased by 3.73 folds, C max increased from 93.50 ± 11.29 to 349.00 ± 29.65ng/mL and AUC increased from 913.02 ± 79.09 to 2451.25 ± 569.65ng/ml/h with cocrystals of resveratrol a much better than resveratrol. The experiment showed promising results, wherein it is found out that the synthesized resveratrol cocrystals exhibits remarkable efficacy in mitigating sciatic pain induced by chronic constriction injury (CCI), exhibiting potent antioxidant and anti-inflammatory properties. The optimized development of resveratrol cocrystals with suitable conformers will be helpful in new drug development in the pain therapeutics with improved pharmacokinetic and pharmacodynamics.
... Lasègue described a test in 1864 for sciatica pain that was eventually named after him (Siddiq et al., 2020). In the general public, the prevalence of clinically confirmed sciatica is between 2% and 5% (Shiri et al., 2017). A lumbar column ruptured intervertebral disc is thought to cause around 90% of instances of sciatica (Grøvle et al., 2013). ...
... Lifestyle factors like smoking, obesity, and leisure-time activity (4-9), sociodemographic, and psychological factors like age, gender, and depression (10)(11)(12)(13)(14) are some of the more studied factors. However, there are some effective but less studied factors compared to those mentioned above, such as nutrition (14,15), massage therapy (16)(17)(18), and especially using essential oils like White Lily oil (19). ...
: To study the effect of four interventions on lower back pain (LBP) alongside time and to identify whether changes in nutrition and doing traditional Persian remedies (massage and rubbing white Lily oil) could relieve the LBP using a short-time treatment. The population of this study consisted of 89 subjects with chronic LBP collected in traditional Persian medicine clinics. The outcomes were two indices for LBP, Oswestry disability index (ODI), and numerical rating scale (NRS), measured three times with an interval of four weeks. Age was not an effective variable in both LBP indices. Effective interventions for both indices are almost the same. For ODI, sex (= male), nutrition, massage, using White Lily oil, and time had decreasing effects on ODI, but interactions of sex with nutrition and massage had increasing effects on ODI. For NRS, sex (= female), using White Lily oil, time, and interactions of sex with massage and nutrition had decreasing effects, but nutrition, massage, and interactions of sex with White Lily oil had increasing effects on NRS.
... Second, lifestyles information such as smoking, is also unavailable in the NHIRD. A strongly association between smoking and sciatica was confirmed by several studies [13,21]. This could also influence the outcome of this study. ...
Background
Several diseases are associated with herpes zoster (HZ). However, whether sciatica is a stressor leading to HZ development remains unclear. Here, we evaluated the occurrence of HZ in patients with sciatica.
Methods
The sciatica cohort consisted of patients first diagnosed as having sciatica between 2000 and 2012. All patients with sciatica were randomly age, sex and index year matched with control individuals without sciatica. The primary outcome was diagnosis of HZ. All individuals were followed until HZ diagnosis, withdrawal from the insurance, death, or December 31, 2013, whichever occurred first. HZ risk in the two cohorts was further analyzed with age, sex and comorbidity stratification.
Results
In total, 49,023 patients with sciatica and 49,023 matched controls were included. Female patients were more likely to have HZ development than were male patients [adjusted hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02–1.12]. After adjustments for all the covariates, HZ risk was significantly higher in the sciatica cohort than in the control cohort (adjusted HR = 1.19; 95% CI = 1.12–1.25).
Conclusion
Sciatica increased HZ risk. Thus, HZ risk should be addressed whenever physicians encounter patients with sciatica, HZ vaccination should be considered especially those aged over 50.
... Regular exercise programs including the cognitive behavioral approach can attenuate chronic pain and improve patients' lifestyle [25][26][27] . Addressing the change of lifestyle including exercise behavior in CP patients is a first-line intervention to reduce the socioeconomic burden related to chronic pain as well as other non-communicable diseases 28,29 . ...
Chronic pain (CP) is a global problem extensively associated with an unhealthy lifestyle. Time discounting (TD), a tendency to assign less value to future gains than to present gains, is an indicator of the unhealthy behaviors. While, recent neuroimaging studies implied overlapping neuro mechanisms underlying CP and TD, little is known about the specific relationship between CP and TD in behavior or neuroscience. As such, we investigated the association of TD with behavioral measures in CP and resting-state brain functional network in both CP patients and healthy subjects. Behaviorally, TD showed a significant correlation with meaningfulness in healthy subjects, whereas TD in patients only correlated with pain intensity. We identified a specific network including medial and dorsolateral prefrontal cortex (PFC) in default mode network (DMN) associated with TD in healthy subjects that showed significant indirect mediation effect of meaningfulness on TD. In contrast, TD in patients was correlated with functional connectivity between dorsolateral PFC (DLPFC) and temporal lobe that mediated the effect of pain intensity on TD in patients. These results imply that TD is modulated by pain intensity in CP patients, and the brain function associated to TD is shifted from a medial to lateral representation within the frontal regions.
... Hence, it is reasonable to expect workplace injury prevention-like strategies taking place within the chiropractic setting, by not only treating injured workers but discussing the modification of physical and psychosocial factors (i.e., patient fear and sense of vulnerability related to injury) to reduce injury risk and cost [62]. Structured exercise is one intervention shown to be protective in managing LBRLP in the short-term [63], while physical activity, i.e., walking and cycling [64], is also protective against work-related LBRLP [65]. While a national-based study found that 85% of Australian chiropractors report discussing physical activity and/or exercise interventions with patients [22], whether these discussions specifically target work-related injuries and LBRLP remains unclear. ...
Background
Approximately 60% of people with low back pain also have associated leg pain symptoms. Guidelines for low back pain recommend non-pharmacological approaches, including spinal manipulation - a therapy provided by chiropractors. However, limited empirical data has examined the characteristics of chiropractors managing patients with low back-related leg pain (LBRLP). Our objective is to describe the prevalence, profile and practice characteristics of Australian chiropractors who often treat LBRLP, compared to those who do not often treat LBRLP.
Methods
This is a cross-sectional analysis of a nationally representative sample from the Australian Chiropractic Research Network (ACORN). This study investigated the demographic and practice characteristics as well as clinical management of chiropractors who ‘often’ treated patients with LBRLP compared to those who treated LBRLP ‘never/rarely/sometimes’. Multiple logistic regression models identified independent factors associated with chiropractors who ‘often’ treated patients with LBRLP.
Results
A total of 1907 chiropractors reported treating patients experiencing LBRLP, with 80.9% of them ‘often’ treating LBRLP. Chiropractors who ‘often’ treated LBRLP were more likely to manage patients with multi-site pain including axial low back pain (OR = 21.1), referred/radicular neck pain (OR = 10.8) and referred/radicular thoracic pain (OR = 3.1). While no specific management strategies were identified, chiropractors who ‘often’ treated LBRLP were more likely to discuss medication (OR = 1.8), manage migraine (OR = 1.7) and degenerative spine conditions (OR = 1.5), and treat women during pregnancy (OR = 1.6) and people with work-related injuries (OR = 1.5), compared to those not treating LBRLP frequently.
Conclusions
Australian chiropractors frequently manage LBRLP, although the nature of specific management approaches for this condition remains unclear. Further research on the management of LBRLP can better inform policy makers and educators interested in upskilling chiropractors to deliver safe and effective treatment of LBRLP.
... Hence, it is reasonable to expect workplace injury prevention-like strategies taking place within the chiropractic setting, by not only treating injured workers but discussing the modification of physical and psychosocial factors (i.e., patient fear and sense of vulnerability related to injury) to reduce injury risk and cost [62]. Structured exercise is one intervention shown to be protective in managing LBRLP in the short-term [63], while physical activity, i.e., walking and cycling [64], is also protective against work-related LBRLP [65]. While a national-based study found that 85% of Australian chiropractors report discussing physical activity and/or exercise interventions with patients [22], whether these discussions specifically target work-related injuries and LBRLP remains unclear. ...
Objective
To examine the prevalence and profile of chiropractors who frequently manage people aged 65 years and older.
Methods
A national cross‐sectional survey collected practitioner characteristics, practice settings and clinical management characteristics. Multiple logistic regression was conducted on 1903 chiropractors to determine the factors associated with the frequent treatment of people 65 years and older.
Results
In total, 73.5% of participants report “often” treating those aged 65 years and older. These chiropractors were associated with treating degenerative spine conditions (OR [odds ratio] 2.25; 95% [confidence interval] CI 1.72‐2.94), working in a non‐urban area (OR 1.85; 95% CI 1.35‐2.54), treating low back pain (referred/radicular) (OR 1.74; 95% CI 1.26‐2.40) and lower limb musculoskeletal disorders (OR 1.50; 95% CI 1.15‐1.96).
Conclusions
The majority of chiropractors report often providing treatment to older people. Our findings call for more research to better understand older patient complaints that are common to chiropractic practice and the care provided by chiropractors for this patient group.
... Awareness of the need of regular physical activity should be enhanced as it has positive effect not only on musculoskeletal system but also on cardio-vascular system. It has been found that walking or cycling to work lowers the risk of hospitalisation due to sciatica by 30 % (Shiri et al., 2017). Despite physical activity is every day routine in PW there is high risk of overload of musculoskeletal system due to unvarying character of activity. ...
The aim of our study was to characterize back pain according to the occupation comprising physical and office work. Accordingly questionnaires from 100 physical workers (PW) and 100 office workers (OW) were collected. This dedicated questionnaire included 19 questions, of which 7 concerned demographic, work and stature features and 12 concerned back pain. Collected data showed that lower back pain was more common in PW but cervical pain in OW (p<0.001). Most common aetiology of back pain was spinal osteoarthritis, sciatica and scoliosis but of different spread in two groups (p<0.001). The history of back pain was most often above 5 years and there were significant differences in frequency, intensity and pain handling methods between groups (p<0.005). Back pain prophylaxis was well acknowledged in both groups (85% in OW, 91% in PW). Regular physical activity was considered the main prophylaxis method (67% in PW, 89% in OW) and similarly incorporated in both groups (p=0.691) however OW more often performed physical exercises (p<0.001). Physical therapy was used in both groups (PW 100%, OW 92%, p=0.004) but with variable efficacy according to responders. To conclude there were multiple differences between both groups in terms of the pain characteristic but with similar awareness and incorporated prophylaxis.
Objective: Previous studies are insufficient to confirm a causal association between physical activity (PA) and low back pain (LBP), intervertebral disc degeneration (IDD), and sciatica. The present study used a two-sample Mendelian randomization (MR) analysis method to demonstrate whether or not there was a causal connection.
Methods: First, four PA phenotypes were selected [accelerometer-based PA (average acceleration), accelerometer-based PA (acceleration fraction >425 mg), self-reported moderate-to-vigorous PA, and self-reported vigorous PA], setting thresholds for single nucleotide polymorphisms (SNPs) significantly concerned with PA p < 5 × 10⁻⁸, linkage disequilibrium (LD) r ² < 0.01, genetic distance >5,000 kb, and F-value >10. SNPs associated with the outcome and confounding factors were then excluded using the PhenoScanncer database. Finally, after coordinating the genetic instruments from genome-wide association studies (GWAS) effect alleles for exposure and outcomes, multiplicative random effects inverse variance weighting (IVW), MR-Egger, weighted median method (WMM), and weighted mode method were used to assess exposure-outcome causality and perform sensitivity analysis on the estimated results.
Results: The current study’s IVW findings revealed proof of a causal connection between PA and LBP. While there was a positive causal tie between accelerometer-based PA (acceleration fraction >425 mg) and LBP [OR: 1.818, 95% CI:1.129–2.926, p = 0.012], there was a negative causal link between accelerometer-based PA (average acceleration) and LBP [OR: 0.945, 95% CI: 0.909–0.984, p = 0.005]. However causal relationship between PA and IDD or sciatica was not found.
Conclusion: Increasing average PA but needing to avoid high-intensity PA may be an effective means of preventing low back pain. Although PA is not directly causally related to disc degeneration and sciatica, it can act through indirect pathways.
Background
Although percutaneous endoscopic lumbar discectomy (PELD) has been popularized as an alternative to microscopic lumbar discectomy, it has been reported to be associated with a re-herniation rate of 5–11%. Recurrent lumbar disc herniation (RLDH) might occur not only at the same level previously operated upon but also at the annular penetration site created during PELD procedures.
Method
Biportal endoscopic paraspinal approach (BE-Para) was used for revisional foraminal lumbar discectomy. Procedures and some discussions regarding indications, advantages, potential complications, and ways to avoid complications were described.
Conclusion
BE-Para may be an effective modality for RLDH after PELD.
Objectives
Smoking has negative consequences on occupational health. The current meta-analysis was conducted with the aim to pool the studies about smoking and increased disability pension.
Study design
Systematic review and meta-analysis.
Methods
Articles were found in the scientific literature using keywords, and searching was limited to prospective cohort studies that had been published before August 2018. Based on the inclusion and exclusion criteria, 23 prospective cohort studies were selected. The analyses were carried out on the basis of the random-effects method. Subgroup analysis was also carried out. Finally, the bias of publication was examined using Begg's test, the Egger test, the trim-and-fill method, and the funnel plot.
Results
Twenty-three studies were included. The results showed a positive association between smoking and disability pension, with a risk ratio (RR) of 1.41 and 95% confidence interval (95% CI) of 1.30–1.53 (P < 0.001). In men, the RR was equal to 1.48 and 95% CI was equal to 1.30–1.68 (P < 0.001). In women, the RR was equal to 1.23 and 95% CI was equal to 1.09–1.37 (P = 0.001). In current smokers, the RR was equal to 1.41 and 95% CI was equal to 1.26–1.57 (P < 0.001). In former smokers, the RR was equal to 1.16 and 95% CI was equal to 1.05–1.29 (P = 0.003). Qualitative evaluation showed that the studies had a low level of selection bias, data collection bias, and withdrawal and dropout bias.
Conclusions
Smoking is a risk factor for increasing disability pension, and men are at higher risk of disability pension. In addition, both current and former smokers are in high risk of disability pension. Overall, it can be concluded that smoking is a risk factor for occupational health.
Smoking has various negative effects on diseases and disabilities. The authors examined the relationships between smoking and physical impairments in this meta-analysis. Two databases including PubMed, Scopus, and two gray literature databases including Google Scholar and Research Gate were searched systematically using Mesh keywords. After reviewing the studies, 18 Prospective cohort studies were selected based on criteria. Risk Ratio (RR) of physical impairment as outcome of smoking and subgroup analysis based on gender, adjusted quality, geographic location and smoking status were done using random effects. Publication bias was calculated as well. The results showed that the risk of physical impairment in smokers is equal to RR = 1.26 and CI = 1.16–1.36 (P = <001). In women, RR = 1.19 and CI = 0.80–1.75 (P = 0.388); and in men, RR = 1.87 and CI = 1.31–2.68 (P = <001) were achieved. Some evidences of publication bias were found. Smoking increases the risk of physical impairment. Men are at a greater risk of physical impairment; perhaps because the prevalence of smoking in men is higher than women.
Objectives
To examine whether exposure to heavy physical work from early to later adulthood is associated with primary healthcare visits due to cause-specific musculoskeletal diseases in midlife.
Design
Prospective cohort study.
Setting
Nationally representative Young Finns Study cohort, Finland.
Participants
1056 participants of the Young Finns Study cohort.
Exposure measure
Physical work exposure was surveyed in early (18–24 years old, 1986 or 1989) and later adulthood (2007 and 2011), and it was categorised as: ‘no exposure’, ‘early exposure only’, ‘later exposure only’ and ‘early and later exposure’.
Primary and secondary outcome measures
Visits due to any musculoskeletal disease and separately due to spine disorders, and upper extremity disorders were followed up from national primary healthcare register from the date of the third survey in 2011 until 2014.
Results
Prevalence of any musculoskeletal disease during the follow-up was 20%, that for spine disorders 10% and that for upper extremity disorders 5%. Those with physically heavy work in early adulthood only had an increased risk of any musculoskeletal disease (risk ratio (RR) 1.55, 95% CI 1.05 to 2.28) after adjustment for age, sex, smoking, body mass index, physical activity and parental occupational class. Later exposure only was associated with visits due to any musculoskeletal disease (RR 1.46, 95% CI 1.01 to 2.12) and spine disorders (RR 2.40, 95% CI 1.41 to 4.06). Early and later exposure was associated with all three outcomes: RR 1.99 (95% CI 1.44 to 2.77) for any musculoskeletal disease, RR 2.43 (95% CI 1.42 to 4.14) for spine disorders and RR 3.97 (95% CI 1.86 to 8.46) for upper extremity disorders.
Conclusions
To reduce burden of musculoskeletal diseases, preventive actions to reduce exposure to or mitigate the consequences of physically heavy work throughout the work career are needed.
Background
There are plausible mechanisms whereby leisure time physical activity may protect against low back pain (LBP) but there have been no quality systematic reviews and meta-analyses of the subject.
Objective
This review aims to assess the effect of leisure time physical activity on non-specific LBP.
Methods
Literature searches were conducted in PubMed, Embase, Web of Science, Scopus and Google Scholar databases from their inception through July 2016. Methodological quality of included studies was evaluated. A random-effects meta-analysis was performed, and heterogeneity and publication bias were assessed.
Results
Thirty-six prospective cohort studies (n=158 475 participants) qualified for meta-analyses. Participation in sport or other leisure physical activity reduced the risk of frequent or chronic LBP, but not LBP for >1 day in the past month or past 6–12 months. Risk of frequent/chronic LBP was 11% lower (adjusted risk ratio (RR)=0.89, CI 0.82 to 0.97, I²=31%, n=48 520) in moderately/highly active individuals, 14% lower (RR=0.86, CI 0.79 to 0.94, I²=0%, n=33 032) in moderately active individuals and 16% lower (RR=0.84, CI 0.75 to 0.93, I²=0%, n=33 032) in highly active individuals in comparison with individuals without regular physical activity. For LBP in the past 1–12 months, adjusted RR was 0.98 (CI 0.93 to 1.03, I²=50%, n=32 654) for moderate/high level of activity, 0.94 (CI 0.84 to 1.05, I²=3%, n=8549) for moderate level of activity and 1.06 (CI 0.89 to 1.25, I²=53%, n=8554) for high level of activity.
Conclusions
Leisure time physical activity may reduce the risk of chronic LBP by 11%–16%. The finding, however, should be interpreted cautiously due to limitations of the original studies. If this effect size is proven in future research, the public health implications would be substantial.
Meta-analysis using individual participant data (IPD) obtains and synthesises the raw, participant-level data from a set of relevant studies. The IPD approach is becoming an increasingly popular tool as an alternative to traditional aggregate data meta-analysis, especially as it avoids reliance on published results and provides an opportunity to investigate individual-level interactions, such as treatment-effect modifiers. There are two statistical approaches for conducting an IPD meta-analysis: one-stage and two-stage. The one-stage approach analyses the IPD from all studies simultaneously, for example, in a hierarchical regression model with random effects. The two-stage approach derives aggregate data (such as effect estimates) in each study separately and then combines these in a traditional meta-analysis model. There have been numerous comparisons of the one-stage and two-stage approaches via theoretical consideration, simulation and empirical examples, yet there remains confusion regarding when each approach should be adopted, and indeed why they may differ. In this tutorial paper, we outline the key statistical methods for one-stage and two-stage IPD meta-analyses, and provide 10 key reasons why they may produce different summary results. We explain that most differences arise because of different modelling assumptions, rather than the choice of one-stage or two-stage itself. We illustrate the concepts with recently published IPD meta-analyses, summarise key statistical software and provide recommendations for future IPD meta-analyses. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.
Background and objective: The clinical course of patients with sciatica is believed to be favourable, but there is conflicting evidence on the postoperative course of this condition. We aimed to investigate the clinical course of sciatica following surgery.
Databases and data treatment: An electronic search was conducted on MEDLINE, EMBASE and CINAHL from inception to April 2015. We screened for prospective cohort studies investigating pain or disability outcomes for patients with sciatica treated surgically. Fractional polynomial regression analysis was used to generate pooled means and 95% confidence intervals (CI) of pain and disability up to 5 years after surgery. Estimates of pain and disability (converted to a 0–100 scale) were plotted over time, from inception to last available follow-up time.
Results: Forty records (39 cohort studies) were included with a total of 13,883 patients with sciatica. Before surgery, the pooled mean leg pain score was 75.2 (95% CI 68.1–82.4) which reduced to 15.3 (95% CI 8.5–22.1) at 3 months. Patients were never fully recovered in the long-term and pain increased to 21.0 (95% CI 12.5–29.5) at 5 years. The pooled mean disability score before surgery was 55.1 (95% CI 52.3–58.0) and this decreased to 15.5 (95% CI 13.3–17.6) at 3 months, and further reduced to 13.1 (95% CI 10.6–15.5) at 5 years.
Conclusions: Although surgery is followed by a rapid decrease in pain and disability by 3 months, patients still experience mild to moderate pain and disability 5 years after surgery.
What does this review add?
This review provides a quantitative summary of the postoperative course of patients with sciatica. Patients with sciatica experienced a rapid reduction in pain and disability in the first 3 months, but still had mild to moderate symptoms 5 years after surgery. Although no significant differences were found, microdiscectomy showed larger improvements compared to other surgical techniques.
Background and objective
The role of leisure-time physical activity in sciatica is uncertain. This study aimed to assess the association of leisure-time physical activity with lumbar radicular pain and sciatica.
Databases and data treatment
Literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1964 through August 2015. A random-effects meta-analysis was performed, and heterogeneity and small-study bias were assessed.
Results
Ten cohort (N = 82,024 participants), four case–control (N = 9350) and four cross-sectional (N = 10,046) studies qualified for meta-analysis. In comparison with no regular physical activity, high level of physical activity (≥4 times/week) was inversely associated with new onset of lumbar radicular pain or sciatica in a meta-analysis of prospective cohort studies [risk ratio (RR) = 0.88, 95% CI 0.78–0.99, I2 = 0%, 7 studies, N = 78,065]. The association for moderate level of physical activity (1–3 times/week) was weaker (RR = 0.93, CI 0.82–1.05, I2 = 0%, 6 studies, N = 69,049), and there was no association with physical activity for at least once/week (RR = 0.99, CI 0.86–1.13, 9 studies, N = 73,008). In contrast, a meta-analysis of cross-sectional studies showed a higher prevalence of lumbar radicular pain or sciatica in participants who exercised at least once/week [prevalence ratio (PR) = 1.29, CI 1.09–1.53, I2 = 0%, 4 studies, N = 10,046], or 1–3 times/week (PR = 1.34, CI 1.02–1.77, I2 = 0%, N = 7631) than among inactive participants. There was no evidence of small-study bias.
Conclusions
This meta-analysis suggests that moderate to high level of leisure physical activity may have a moderate protective effect against development of lumbar radicular pain. However, a large reduction in risk (>30%) seems unlikely.
What does this review add
Leisure-time physical activity may reduce the risk of developing lumbar radicular pain.
The aim of this study was to assess the associations of overweight and obesity with lumbar radicular pain and sciatica using a meta-analysis. We searched the PubMed, Embase, Scopus, and Web of Science databases from 1966 to July 2013. We performed a random-effects meta-analysis and assessed publication bias. We included 26 (8 cross-sectional, 7 case-control, and 11 cohort) studies. Both overweight (pooled odds ratio (OR) = 1.23, 95% confidence interval (CI): 1.14, 1.33; n = 19,165) and obesity (OR = 1.40, 95% CI: 1.27, 1.55; n = 19,165) were associated with lumbar radicular pain. The pooled odds ratio for physician-diagnosed sciatica was 1.12 (95% CI: 1.04, 1.20; n = 109,724) for overweight and 1.31 (95% CI: 1.07, 1.62; n = 115,661) for obesity. Overweight (OR = 1.16, 95% CI: 1.09, 1.24; n = 358,328) and obesity (OR = 1.38, 95% CI: 1.23, 1.54; n = 358,328) were associated with increased risk of hospitalization for sciatica, and overweight/obesity was associated with increased risk of surgery for lumbar disc herniation (OR = 1.89, 95% CI: 1.25, 2.86; n = 73,982). Associations were similar for men and women and were independent of the design and quality of included studies. There was no evidence of publication bias. Our findings consistently showed that both overweight and obesity are risk factors for lumbar radicular pain and sciatica in men and women, with a dose-response relationship.
Background
Few studies have investigated prognostic factors for patients with sciatica, especially for patients treated without surgery. The aim of this study was to identify factors associated with non-success after 1 and 2 years of follow-up and to test the prognostic value of surgical treatment for sciatica.
Methods
The study was a prospective multicentre observational study including 466 patients with sciatica and lumbar disc herniation. Potential prognostic factors were sociodemographic characteristics, back pain history, kinesiophobia, emotional distress, pain, comorbidity and clinical examination findings. Study participation did not alter treatment considerations for the patients in the clinics. Patients reported on the questionnaires if surgery of the disc herniation had been performed. Uni- and multivariate logistic regression analyses were used to evaluate factors associated with non-success, defined as Maine–Seattle Back Questionnaire score of ≥5 (0–12) (primary outcome) and Sciatica Bothersomeness Index ≥7 (0–24) (secondary outcome).
Results
Rates of non-success were at 1 and 2 years 44% and 39% for the main outcome and 47% and 42% for the secondary outcome. Approximately 1/3 of the patients were treated surgically. For the main outcome variable, in the final multivariate model non-success at 1 year was significantly associated with being male (OR 1.70 [95% CI; 1.06 − 2.73]), smoker (2.06 [1.31 − 3.25]), more back pain (1.0 [1.01 − 1.02]), more comorbid subjective health complaints (1.09 [1.03 − 1.15]), reduced tendon reflex (1.62 [1.03 − 2.56]), and not treated surgically (2.97 [1.75 − 5.04]). Further, factors significantly associated with non-success at 2 years were duration of back problems >; 1 year (1.92 [1.11 − 3.32]), duration of sciatica >; 3 months (2.30 [1.40 − 3.80]), more comorbid subjective health complaints (1.10 [1.03 − 1.17]) and kinesiophobia (1.04 [1.00 − 1.08]). For the secondary outcome variable, in the final multivariate model, more comorbid subjective health complaints, more back pain, muscular weakness at clinical examination, and not treated surgically, were independent prognostic factors for non-success at both 1 and 2 years.
Conclusions
The results indicate that the prognosis for sciatica referred to secondary care is not that good and only slightly better after surgery and that comorbidity should be assessed in patients with sciatica. This calls for a broader assessment of patients with sciatica than the traditional clinical assessment in which mainly the physical symptoms and signs are investigated.
Aims:
The Finnish Hospital Discharge Register (FHDR) is one of the oldest individual level hospital discharge registers and has been intensively used for research purposes. The aim of this study was to gather information concerning the quality of FHDR into one place in terms of a systematic review of validation studies that compare data to external information.
Methods:
Several reference databases were searched for validity articles published until January 2012. For each included study, focus of validation, register years examined, number of compared observations, external source(s) of data, summary of validation results, and conclusions concerning the validity of FHDR were extracted.
Results:
In total, 32 different studies comparing FHDR data to external information were identified. Most of the studies examined validity in the case of vascular disease, mental disorders or injuries. More than 95% of discharges could be identified from the register. Positive predictive value (PPV) for common diagnoses was between 75 and 99%.
Conclusions:
Completeness and accuracy in the register seem to vary from satisfactory to very good in the register as long as the recognised limitations are taking into account. Poor recording of subsidiary diagnoses and secondary operations and other rarely used items are the most obvious limitations in validity, but do not compromise the value of data in FHDR in being used in studies that are not feasible to conduct otherwise.
Research studies focusing on the fear-avoidance model have expanded considerably since the review by Vlaeyen and Linton (Vlaeyen J. W. S. & Linton, S. J. (2000). Fear-avoidance and its consequences in chronic musculoskeletal pain: a state of the art. Pain, 85(3), 317--332). The fear-avoidance model is a cognitive-behavioral account that explains why a minority of acute low back pain sufferers develop a chronic pain problem. This paper reviews the current state of scientific evidence for the individual components of the model: pain severity, pain catastrophizing, attention to pain, escape/avoidance behavior, disability, disuse, and vulnerabilities. Furthermore, support for the contribution of pain-related fear in the inception of low back pain, the development of chronic low back pain from an acute episode, and the maintenance of enduring pain, will be highlighted. Finally, available evidence on recent clinical applications is provided, and unresolved issues that need further exploration are discussed.
Both low back pain (LBP) and obesity are common public health problems, yet their relation remains controversial. The aim of this study was to investigate the associations between weight-related factors and the prevalence of LBP in young adults in Finland. Participants in the ongoing Cardiovascular Risk in Young Finns Study aged 24-39 years were included (N = 2,575). In 2001, 31.2% of men and 39.5% of women reported LBP with recovery within a month or recurrent or continuous pain during the preceding 12 months. For women only, those with higher body mass index, waist circumference, hip circumference, waist-to-hip ratio, serum leptin level, and C-reactive protein level showed an increased prevalence of LBP. With all weight-related factors in the model, only waist circumference was related to LBP in women. For women, the odds ratios of LBP were 1.2 (95% confidence interval: 0.8, 1.8) for a waist circumference of 80-87.9 cm and 1.8 (95% confidence interval: 1.0, 3.2) for a waist circumference of > or =88 cm compared with a waist circumference of <80 cm. This association was independent of C-reactive protein, leptin, and adiponectin levels. The authors' findings in a relatively young population suggest that abdominal obesity may increase the risk of LBP in women.
To examine nonparticipation to a questionnaire survey and occupational health check-ups by sociodemographic variables and health status, measured by medically confirmed sickness absence, and whether the associations between other study variables and participation were affected by health status.
Questionnaire surveys and health check-ups were conducted among the City of Helsinki employees. Sample information was derived from the employer's personnel register and analyzed by participation and giving consent to link the data to external administrative registers.
Participation to the questionnaire survey was more common among the older, higher occupational classes, those with higher income, permanent employment, and those with no absence due to medically confirmed sickness. Among women in particular, the differences were small. Consent giving followed generally similar patterns than survey response. Nonparticipation to health check-ups was related to low income and temporary employment contract. In both questionnaire survey and health check-ups, associations between other study variables and participation were not affected by health status.
Questionnaire surveys and health check-ups were broadly representative of the target population. Associations between other study variables and participation did not differ by health status. This suggests that even when the data are not fully representative associations between the study variables need not to be biased.
Background
The role of smoking in sciatica is unknown. This study aimed to estimate the effect of smoking on lumbar radicular pain and clinically verified sciatica.
Methods
Comprehensive literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1964 through March 2015. We used a random-effects meta-analysis, assessed heterogeneity and publication bias, and performed sensitivity analyses with regard to study design, methodological quality of included studies and publication bias.
Results
Twenty-eight (7 cross sectional [N=20,111 participants], 8 case control [N=10,815] and 13 cohort [N=443,199]) studies qualified for a meta-analysis. Current smokers had an increased risk of lumbar radicular pain or clinically verified sciatica (pooled adjusted odds ratio [OR] =1.46, 95% confidence interval [CI] 1.30-1.64, N=459,023). Former smokers had only slightly elevated risk than never smokers (pooled adjusted OR=1.15, CI 1.02-1.30, N=387,196). For current smoking the pooled adjusted OR was 1.64 (CI 1.24-2.16, N=10,853) for lumbar radicular pain, 1.35 (CI 1.09-1.68, N=110,374) for clinically verified sciatica, and 1.45 (CI 1.16-1.80, N=337,796) for hospitalization or surgery due to a herniated lumbar disc. The corresponding estimates for past smoking were 1.57 (CI 0.98-2.52), 1.09 (CI 1.00-1.19), and 1.10 (CI 0.96-1.26). The associations did not differ between men and women, and they were independent of study design. Moreover, there was no evidence of publication bias, and the observed associations were not due to selection or detection bias, or confounding factors.
Conclusions
Smoking is a modest risk factor for lumbar radicular pain and clinically verified sciatica. Smoking cessation appears to reduce, but not entirely eliminate, the excess risk.
Background:
Questions remain as to the effect that obesity has on patients managed for symptomatic lumbar disc herniation. The purpose of this study was to determine if obesity affects outcomes following the treatment of symptomatic lumbar disc herniation.
Methods:
An as-treated analysis was performed on patients enrolled in the Spine Patient Outcomes Research Trial for the treatment of lumbar disc herniation. A comparison was made between patients with a body mass index of <30 kg/m² (nonobese) (n = 854) and those with a body mass index of ≥30 kg/m² (obese) (n = 336). Baseline patient demographic and clinical characteristics were documented. Primary and secondary outcomes were measured at baseline and at regular follow-up time intervals up to four years. The difference in improvement from baseline between operative and nonoperative treatment was determined at each follow-up period for both groups.
Results:
At the time of the four-year follow-up evaluation, improvements over baseline in primary outcome measures were significantly less for obese patients as compared with nonobese patients in both the operative treatment group (Short Form-36 physical function, 37.3 compared with 47.7 points [p < 0.001], Short Form-36 bodily pain, 44.2 compared with 50.0 points [p = 0.005], and Oswestry Disability Index, -33.7 compared with -40.1 points [p < 0.001]) and the nonoperative treatment group (Short Form-36 physical function, 23.1 compared with 32.0 points [p < 0.001] and Oswestry Disability Index, -21.4 compared with -26.1 points [p < 0.001]). The one exception was that the change from baseline in terms of the Short Form-36 bodily pain score was statistically similar for obese and nonobese patients in the nonoperative treatment group (30.9 compared with 33.4 points [p = 0.39]). At the time of the four-year follow-up evaluation, when compared with nonobese patients who had been managed operatively, obese patients who had been managed operatively had significantly less improvement in the Sciatica Bothersomeness Index and the Low Back Pain Bothersomeness Index, but had no significant difference in patient satisfaction or self-rated improvement. In the present study, 77.5% of obese patients and 86.9% of nonobese patients who had been managed operatively were working a full or part-time job. No significant differences were observed in the secondary outcome measures between obese and nonobese patients who had been managed nonoperatively. The benefit of surgery over nonoperative treatment was not affected by body mass index.
Conclusions:
Obese patients realized less clinical benefit from both operative and nonoperative treatment of lumbar disc herniation. Surgery provided similar benefit over nonoperative treatment in obese and nonobese patients.
Low back pain in young athletes is a common complaint and should be taken seriously. It frequently results from a structural injury that requires a high degree of suspicion to diagnose and treat appropriately.
A Medline search was conducted from 1996 to May 2008 using the search terms "low back pain in children" and "low back pain in athletes." Known texts on injuries in young athletes were also reviewed. References in retrieved articles were additionally searched for relevant articles. Sources were included if they contained information regarding diagnosis and treatment of causes of low back pain in children.
Low back pain is associated with sports involving repetitive extension, flexion, and rotation, such as gymnastics, dance, and soccer. Both acute and overuse injuries occur, although overuse injuries are more common. Young athletes who present with low back pain have a high incidence of structural injuries such as spondylolysis and other injuries to the posterior elements of the spine. Disc-related pathology is much less common. Simple muscle strains are much less likely in this population and should be a diagnosis of exclusion only.
Young athletes who present with low back pain are more likely to have structural injuries and therefore should be investigated fully. Muscle strain should be a diagnosis of exclusion. Treatment should address flexibility and muscle imbalances. Injuries can be prevented by recognizing and addressing risk factors. Return to sport should be a gradual process once the pain has resolved and the athlete has regained full strength.
To investigate the mechanisms by which chronic tobacco smoking promotes intervertebral disc degeneration (IDD) and vertebral degeneration in mice.
Three month old C57BL/6 mice were exposed to tobacco smoke by direct inhalation (4 cigarettes/day, 5 days/week for 6 months) to model long-term smoking in humans. Total disc proteoglycan (PG) content [1,9-dimethylmethylene blue (DMMB) assay], aggrecan proteolysis (immunobloting analysis), and cellular senescence (p16INK4a immunohistochemistry) were analyzed. PG and collagen syntheses ((35)S-sulfate and (3)H-proline incorporation, respectively) were measured using disc organotypic culture. Vertebral osteoporosity was measured by micro-computed tomography.
Disc PG content of smoke-exposed mice was 63% of unexposed control, while new PG and collagen syntheses were 59% and 41% of those of untreated mice, respectively. Exposure to tobacco smoke dramatically increased metalloproteinase-mediated proteolysis of disc aggrecan within its interglobular domain (IGD). Cellular senescence was elevated two-fold in discs of smoke-exposed mice. Smoke exposure increased vertebral endplate porosity, which closely correlates with IDD in humans.
These findings further support tobacco smoke as a contributor to spinal degeneration. Furthermore, the data provide a novel mechanistic insight, indicating that smoking-induced IDD is a result of both reduced PG synthesis and increased degradation of a key disc extracellular matrix protein, aggrecan. Cleavage of aggrecan IGD is extremely detrimental as this results in the loss of the entire glycosaminoglycan-attachment region of aggrecan, which is vital for attracting water necessary to counteract compressive forces. Our results suggest identification and inhibition of specific metalloproteinases responsible for smoke-induced aggrecanolysis as a potential therapeutic strategy to treat IDD.
Summary The Helsinki Health Study cohort was set up to enable longitudinal studies on the social and work related determinants of health and well-being, making use of self-reported as well as objective register data. The target population is the staff of the City of Helsinki, Finland. Baseline data for the cohort were derived from questionnaire surveys conducted in 2000, 2001 and 2002 among employees reaching 40, 45, 50, 55 or 60 years of age in each year. The number of responders at baseline was 8960 (80% women, response rate 67%). Additional age-based health examination data were available. A follow up survey was conducted in 2007 yielding 7332 responders (response rate 83%). Measures of health include health behaviours, self-rated health, common mental disorders, functioning, pain, sleep problems, angina symptoms and major diseases. Social determinants include socio-demographics, socio-economic circumstances, working conditions, social support, and work-family interface. Further register linkages include sickness absence, hospital discharge, prescribed drugs, and retirement updated at the end of 2010. The cohort allows comparisons with the Whitehall II study, London, UK, and the Japanese Civil Servants Study from western Japan. The cohort data are available for collaborative research at Hjelt Institute, Department of Public Health, University of Helsinki, Finland.
Prospective cohort study.
To study biomechanical factors in relation to symptomatic lumbar disc disease.
The importance of biomechanical factors in lumbar disc disease has been questioned in the past decade and knowledge from large prospective studies is lacking.
The study basis is a cohort of 263,529 Swedish construction workers who participated in a national occupational health surveillance program from 1971 until 1992. The workers' job title, smoking habits, body weight, height, and age were registered at the examinations. The occurrence of hospitalization due to lumbar disc disease from January 1, 1987, until December 31, 2003, was collected from a linkage with the Swedish Hospital Discharge Register.
There was an increased risk for hospitalization due to lumbar disc disease for several occupational groups compared with white-collar workers and foremen. Occupational groups with high biomechanical loads had the highest risks, for example, the relative risk for concrete workers was 1.55 (95% confidence interval [CI], 1.29-1.87). A taller stature was consistently associated with an increased risk. The relative risk for a man of 190- to 199-cm height was 1.55 (95% CI, 1.30-1.86) compared with a man being 170- to 179-cm height. Body weight and smoking were also risk factors, but weaker than height. Workers in the age span of 30 to 39 years had the highest relative risk (RR = 1.87; 95% CI, 1.58-2.23) compared with those aged 20 to 29 years, whereas men aged 60 to 65 years had a lower risk (RR = 0.86; 95% CI, 0.68-1.09).
This study indicates that factors increasing the load on the lumbar spine are associated with hospitalization for lumbar disc disease. Occupational biomechanical factors seem to be important, and a taller stature was consistently associated with an increased risk.
The Compendium of Physical Activities was developed to enhance the comparability of results across studies using self-report physical activity (PA) and is used to quantify the energy cost of a wide variety of PA. We provide the second update of the Compendium, called the 2011 Compendium.
The 2011 Compendium retains the previous coding scheme to identify the major category headings and specific PA by their rate of energy expenditure in MET. Modifications in the 2011 Compendium include cataloging measured MET values and their source references, when available; addition of new codes and specific activities; an update of the Compendium tracking guide that links information in the 1993, 2000, and 2011 compendia versions; and the creation of a Web site to facilitate easy access and downloading of Compendium documents. Measured MET values were obtained from a systematic search of databases using defined key words.
The 2011 Compendium contains 821 codes for specific activities. Two hundred seventeen new codes were added, 68% (561/821) of which have measured MET values. Approximately half (317/604) of the codes from the 2000 Compendium were modified to improve the definitions and/or to consolidate specific activities and to update estimated MET values where measured values did not exist. Updated MET values accounted for 73% of all code changes.
The Compendium is used globally to quantify the energy cost of PA in adults for surveillance activities, research studies, and, in clinical settings, to write PA recommendations and to assess energy expenditure in individuals. The 2011 Compendium is an update of a system for quantifying the energy cost of adult human PA and is a living document that is moving in the direction of being 100% evidence based.
Cohort study.
To examine the association between self-reported physical workload and risk of herniated lumbar disc disease (HLDD) in a long-term follow-up of men without a history of back disorders at baseline.
Heavy physical workload is considered a risk factor for HLDD, but the issue is not definitively settled.
The Copenhagen Male Study is a prospective cohort study established in 1970 to 1971. At baseline, 5245 men answered a questionnaire about history of back disease and physical workload. Psychosocial working conditions, lifestyle, social class, and measured height and weight were included as potential confounders. Information about hospitalization due to HLDD was obtained from the National Hospital Register covering the period from 1977 to 2003. Hazard ratios were calculated by Cox proportional hazard regression model.
Among 3833 men without back disease history at baseline, the strongest predictor of hospitalization for HLDD was frequent strenuous physical activity at work; compared with unexposed, the hazard ratio with 95% confidence interval was 3.90 (1.82-8.38). Also, body height was a significant predictor, whereas body weight was only insignificantly associated with HLDD.
Among men without history of back disease reporting of frequent exposure to strenuous physical activity at work was a strong risk factor for later hospitalization due to HLDD.
Sciatica is a symptom rather than a specific diagnosis. Available evidence from basic science and clinical research indicates that both inflammation and compression are important in order for the nerve root to be symptomatic. Tumour necrosis factor-alpha (TNF-alpha) is a key mediator in animal models, but its exact contribution in human radiculopathy is still a matter of debate. Sciatica is mainly diagnosed by history taking and physical examination. In general, the clinical course of acute sciatica is considered to be favourable. In the first 6-8 weeks, there is consensus that treatment of sciatica should be conservative. We review and comment on the levels of evidence of the efficacy of patient information, advice to stay active, physical therapy analgesics, non-steroidal anti-inflammatory drugs (NSAIDs), epidural corticosteroid injections and transforaminal peri-radicular injections of corticosteroid. There is good evidence that discectomy is effective in the short term. but, in the long term, it is not more effective than prolonged conservative care. Shared decision making with regard to surgery is necessary in the absence of severe progressive neurological symptoms. Although the term sciatica is simple and easy to use, it is, in fact, an archaic and confusing term. For most researchers and clinicians, it refers to a radiculopathy, involving one of the lower extremities, and related to disc herniation (DH). As such, the term 'sciatica' is too restrictive as nerve roots from L1 to L4 may also be involved in the same process. However, even more confusing is the fact that patients, and many clinicians alike, use sciatica to describe any pain arising from the lower back and radiating down to the leg. The majority of the time, this painful sensation is referred pain from the lower back and is neither related to DH nor does it result from nerve-root compression. Although differentiating the radicular pain from the referred pain may be challenging for the clinician, it is of primary importance. This is because the epidemiology, clinical course and, most importantly, therapeutic interventions are different for these two conditions. It should, however, be emphasised that the quality of the available evidence is rather limited due to a considerable heterogeneity in the study populations included in the trials. This makes generalisation of findings across studies, and to routine clinical practice, a challenge. Prevalence estimates of radicular pain related to DH also vary considerably between studies, which is, in part, due to differences in the definitions used. A recent review showed that the prevalence of sciatic symptoms is rather variable, with values ranging from 1.6% to 43%. If stricter definitions of sciatica were used, for example, in terms of pain distribution and/or pain duration, lower prevalence rates were reported. Studies in working populations with physically demanding jobs consistently report higher rates of sciatica compared with studies in the general population.
Several factors were studied for their association with the prevalence of chronic low-back syndromes, sciatica, and unspecified low-back pain (LBP) in 2,946 women and 2,727 men (age range, 30-64 years) participating in the Mini-Finland Health Survey, a project aimed at comprehensive evaluation of the population's health. On the basis of a standardized clinical examination, a physician diagnosed sciatica in 5.1% and LBP in 11.6% of the subjects. Those with a previous traumatic back injury had a 2.5-fold risk of having sciatica or LBP. The fractions of sciatica and LBP attributable to such back injuries were estimated to be 16.5% and 13.7%, respectively. Sum indices of both physical and mental stress at work were found to be directly proportional to the prevalence of sciatica and LBP. Smokers had an increased risk of LBP, and body height was related positively to the prevalence of sciatica. These associations, however, were inconsistent between sex and age subgroups. In the presence of osteoarthritis in the knee, hip, or hand, LBP was prevalent (adjusted odds ratio [OR], 5.3; 95% confidence interval [CI], 4.1-6.9), but sciatica was not (OR, 1.1; 95% CI, 0.7-1.7). Diabetics were found to have a significantly decreased prevalence of LBP (OR, 0.4; 95% CI, 0.3-0.8). Many factors, independent of each other, determine the occurrence of chronic low-back syndromes. The determinants of sciatica and LBP are different to some extent.
The Social Insurance Institution's Coronary Heart Disease Study is a prospective population study designed to investigate the prevalence, risk factors and incidence of coronary heart disease (CHD) in middle-aged Finnish men and women. The study population consisted of 5 738 men and 5 224 women, aged 30-59 years at entry, drawn from 12 cohorts from south-western, western, central and eastern Finland. The cohorts consisted of whole or random samples of rural or semiurban dwellers or employees of a factory. The participation rate was 90 per cent. The prevalence of symptoms was determined by the Rose questionnaire and abnormalities on resting ECG were coded according to the Minnesota code. Blood pressure, smoking habits, serum cholesterol, triglycerides, postload plasma glucose and obesity were the risk factors analysed at the baseline examination. The mortality of examinees has been followed continuously. This report deals with the main findings at the baseline examination and the mortality follow-up experience in 5 years. The prevalence of typical angina pectoris was 4.4 per cent in men and 5.4 per cent in women. Unequivocal ECG signs of past myocardial infarction were observed in 1.0 per cent of men and 0.3 per cent of women. Other ECG findings suggesting CHD were observed in 9.2 per cent of men and 11.1 per cent of women. The 5-year mortality was 4.3 per cent in men and 0.9 per cent in women. Men with typical chest pain symptoms had a seven-fold risk to die from CHD, compared to men without symptoms. Men with ECG abnormalities compatible with an old infarction had a 19.5-fold and men with other ECG findings suggesting CHD a 7.1-fold risk to die from CHD compared to men without resting ECG abnormalities. Men with ECG findings as the only indicator of CHD had worse survival than men with symptoms as the only indicator of CHD. The value of symptoms and ECG findings as predictors of CHD mortality in women was very low.
A 25-year follow-up study of 606 members of the population-based Framingham cohort, who had received lateral lumbar radiographs in 1967-1968 and 1992-1993, and completed an interview on back symptoms at the second examination.
To evaluate whether calcific lesions in the posterior wall of the abdominal aorta, the source of the feeding arteries of the lumbar spine, are associated with disc degeneration or back pain, which would suggest that ischemia of the lumbar spine leads to disc degeneration.
The presence of radiographic aortic calcification was ascertained in front of each lumbar segment from L1 through L4, and disc degeneration at intervertebral spaces from L1-L2 through L4-L5. The associations between aortic calcification, disc degeneration, and back pain were tested using logistic regression with adjustment for age and sex.
At the baseline examination, aortic calcification was significantly associated with general disc degeneration, that is, disc space narrowing or endplate sclerosis at any lumbar level (odds ratio 1.6; 95% confidence interval 1.0-2.5; P = 0.034). In longitudinal, level-specific analyses, comparing local aortic calcifications with disc degeneration at the matching level, aortic calcifications predicted disc deterioration, that is, a decrease in disc space or appearance of endplate sclerosis, between the examinations (odds ratio 1.5; 95% confidence interval 1.3-1.8; P < 0.001). Furthermore, subjects in whom aortic calcifications developed between the examinations had disc deterioration twice as frequently as those in whom aortic calcifications did not develop (odds ratio 2.0; 96% confidence interval 1.2-3.5; P = 0.013). Also, individuals with severe (Grade 3) posterior aortic calcification in front of any lumbar segment were more likely than others to report back pain during adult life (odds ratio 1.6; 95% confidence interval 1.1-2.2; P = 0.014).
Advanced aortic atherosclerosis, presenting as calcific deposits in the posterior wall of the aorta, increases a person's risk for development of disc degeneration and is associated with the occurrence of back pain.
To compare self-reported to measured heights and weights of adults examined in the Third National Health and Nutrition Examination Survey (NHANES III), and to determine to what extent body mass index (BMI) calculated from self-reported heights and weights affects estimates of overweight prevalence compared with BMI calculated from measured values.
A complex sample design was used in NHANES III to obtain a nationally representative sample of the US civilian, noninstitutionalized population. During household interviews, survey respondents were asked their height and weight. Trained health technicians subsequently measured height and weight using standardized procedures and equipment.
The analytical sample consisted of 7,772 men and 8,801 women 20 years old and older.
Only persons with measured and self-reported heights and weights were included in the analysis, and statistical sampling weights were applied. t Tests, Pearson product moment correlation coefficients, sensitivity, and specificity analyses were used to determine the validity of self-reported measurements and prevalence estimates of overweight, defined as BMI of 25 or greater.
Age is an important factor in classifying weight, height, BMI, and overweight from self-reports. Statistically significant differences were found for the mean error (measured-self-reported values) for height and BMI that were notably larger for older age groups. For example, the mean error for height ranged from 2.92 to 4.50 cm for women and from 3.06 to 4.29 cm for men, 70 years and older. Despite the high correlation between measured and self-reported data, the prevalence of overweight calculated from measured values was higher than that calculated from self-reported values among older adults. When calculated with self-reported height, BMI was one unit lower than when calculated from measured height for persons > or = 70 years. Specificity was high but sensitivity decreased with increasing age cohorts. Regression equations are provided to determine actual height from self-reported values for older adults. CONCLUSION/APPLICATIONS: Self-reported heights and weights can be used with younger adults, but they have limitations for older adults, ages > or = 60 years. In research studies and in clinical settings involving older adults, failure to measure height and weight can result in subsequent misclassification of overweight status. Therefore, registered dietitians are encouraged to obtained a measured weight and height using a calibrated scale and stadiometer.
To examine the influence of physical activity on body mass index (BMI), waist circumference (W) and body mass changes (DeltaBMI) in middle-aged men, with special regard to moderate-intensity activities.
Longitudinal study of adults who participated in the PRIME Study.
A cohort of 8865 men aged 50-59 y, free of coronary heart disease.
BMI and W at baseline, body mass changes over a 5 y period. Detailed baseline assessment of net energy expenditure due to physical activity (PAE) in the preceding year, according to category of activity, by means of the MOSPA Questionnaire. PAE was expressed in weekly metabolic equivalent scores (MET h/week).
After adjustment for confounders, the multiple regression analyses indicated that BMI, W and DeltaBMI were inversely associated with PAE spent in getting to work (P<10(-5), <10(-5) and 0.04, respectively) and practice of high-intensity (>or=6 MET) recreational activities (<0.01, <10(-5) and <0.01). Men who regularly spent more than 10 MET h/week in walking or cycling to work had a mean BMI, W and DeltaBMI respectively 0.3 kg/m(2), 1 cm and 0.06 kg/m(2) lower than those who did not expend energy in getting to work. In the subgroup of subjects who did not perform high-intensity activities, the level of recreational PAE was inversely associated with BMI and W but not with subsequent weight-gain.
These findings indicate that, in middle-aged men, physical activities of moderate-intensity, which are probably easier to promote than more vigorous activities and, in particular, a more current daily activity, walking or cycling to work, may have a favourable effect on body fat markers and body mass gain.
A prospective cohort study.
To study the relationship of smoking and overweight with severe back disorders leading to hospitalization.
Many epidemiological studies have shown an association between smoking or overweight and back pain, but the results are still equivocal. Longitudinal studies are few.
A cohort of metal industry employees (n = 902) was studied for lifestyle, work history, and health in 1973 by questionnaire and interview. The weight of the subjects was measured and body mass index (kg/m2) was calculated. Based on intensity and duration, smoking was categorized as: never smoked (reference), stopped smoking, smoked <or=9 or >9 pack-years. Information on hospital admissions from 1973 to 2000 from the Finnish Hospital Discharge Register was linked to the data. Seventy-five individuals had been admitted to hospital because of back disorders. Intervertebral disc disorders and other common back disorders were analyzed separately. Cox proportional hazards regression was used to estimate the time between the assessment of potential risk factors and the first hospitalization for a back disorder.
The rate ratio of heavy smokers (>9 pack-years) for hospitalization because of intervertebral disc disorders was 3.4 (95% confidence interval 1.3-9.0) as compared with never-smokers, allowing for other risk factors. Accordingly, the rate ratio of body mass index >27.5 kg/m2 was 2.7 (1.1-6.45) as compared with people with normal weight. The results retained when patients with chronic back disease at baseline were excluded from the analyses. Other back-related diagnoses of hospitalization were not consistently associated with smoking or overweight.
Heavy smoking and overweight predicted hospitalization for intervertebral disc disorders.
We have investigated the intervertebral discs of rat-smoking models to demonstrate that smoking is a cause of degenerative intervertebral disc disease. A smoking box was developed for this study. We exposed 8-week-old rats to indirect tobacco smoke inhalation. Each rat was forced to inhale the smoke from one cigarette per hour. The mean blood nicotine level of rodents exposed to cigarette smoke corresponds to about twice that of ordinary human smokers. Histological and immunological studies were then performed to assess the effects of smoking for varying periods of time. After 8 weeks, the chondrocytes in the disordered annulus fibrosus layer tended to grow larger and attain a rounder form than normal chondrocytes. The interleukin-1beta level in the 8-week smoking group was significantly higher than that of the control group. Tobacco smoke inhalation increased local production and release of inflammatory cytokines and resultant decomposition of chondrocyte activity.
Experimental investigation to determine the effect of nicotine on intervertebral spinal disc nucleus pulposus (NP) cells cultured in vitro. OBJECTIVES.: To evaluate the effects of nicotine on cell proliferation, extracellular matrix production, and viability of NP cells in three-dimensional alginate constructs cultured in vitro.
Numerous studies confirm that smoking is a strong risk factor for back pain. The most widely accepted explanations for the association between smoking and disc degeneration is malnutrition of spinal disc cells by carboxy-hemoglobin-induced anoxia or vascular disease. Nicotine, a constituent of tobacco smoke, present in most body fluids of smokers is known to have detrimental effects on a variety of tissues. It may also be directly responsible for intervertebral disc (IVD) degeneration by causing cell damage in both the nucleus pulposus and anulus fibrosus. The effect of nicotine on IVD cells has not previously been investigated.
Bovine chondrocytic intervertebral disc cells were isolated by sequential digestion of nucleus pulposus and seeded in 2% alginate. The constructs were cultured for 21 days either in growth medium containing freebase nicotine (Sigma) at concentrations found in the serum of smokers (25 nmol/L-300 nmol/L) or in standard nicotine free-medium as controls. Samples were collected at time points 3, 7, 14, and 21 days and a quantitative assay was performed for DNA, glycosaminoglycans (GAG), and hydroxyproline. Samples were also processed for qualitative histologic analysis including immunolocalization of collagen types I and II.
There was both a dose- and time-dependent response to nicotine, with constructs cultured in low-nicotine concentration media demonstrating an early increase in DNA, GAG, and collagen content, while constructs cultured in high nicotine concentration media demonstrated a late decrease in these parameters. At 25 nmol/L dose of nicotine, there was a significant increase (P < 0.05) in the above parameters at day 7 compared with the controls. At higher doses, there was a significant dose-dependent decrease (P < 0.05) in these parameters compared to controls; however, this was only significant at day 14 for the 300 nmol/L group and at day 21 for the 100 nmol/L, 200 nmol/L, and 300 nmol/L groups. Adverse morphologic changes were observed on histology, which included reduced cell proliferation, disrupted cell architecture, disintegration of cells, and extracellular matrix. Immunohistochemistry revealed the presence of type I collagen in the extracellular matrix rather than the normal type II collagen seen in the controls.
Nicotine has an overall detrimental effect on NP disc cells cultured in vitro. There was significant inhibition of cell proliferation and extracellular matrix synthesis. Nicotine in tobacco smoke may have a role in pathogenesis of disc degeneration.
Passive smoking has been reported to induce intervertebral disc degeneration in rats, and the objective of the present study was to histologically investigate changes in smoking-induced intervertebral disc degeneration after cessation of smoking.
Four-week-old rats were subjected to passive smoking for 8 weeks in a smoking box [20 cigarettes a day: one cigarette an hour (inhaled over 3 minutes and followed by ventilation with room air for 5 minutes)] to induce intervertebral disc degeneration. Smoke-free periods of different lengths were then established, and intervertebral discs were histologically analyzed.
Immediately after 8 weeks of passive smoking, intervertebral discs exhibited cracks, tears, and misalignment of the annulus fibrosus, and increased fibrous tissue was seen in the nucleus pulposus. In addition, the level of interleukin-1beta in intervertebral discs was higher in the smoking group than in the non-smoking group. After cessation, progression of degeneration ceased, and the matrix of the nucleus pulposus and annulus fibrosus exhibited increased fibrous connective tissue and proteoglycan. However, there were no changes in annulus fibrosus misalignment. Interleukin-1beta levels also remained significantly elevated after 8 weeks of cessation.
While the annulus fibrosus degeneration caused by smoking was partially irreversible after cessation of smoking, the amount of mucin (proteoglycan) in the nucleus pulposus and annulus fibrosus tended to increase after cessation, thus suggesting the possibility that smoking-induced intervertebral disc degeneration can be repaired to some degree by cessation of smoking.
Disk-related sciatica (DRS) creates a public health burden because of its high incidence and considerable socioeconomic costs. We are not aware of previous epidemiological studies of the prevalence and risk factors of DRS in Tunisia or other Arab countries, and few studies have addressed these issues elsewhere.
To determine the prevalence and incidence of DRS in Monastir, Tunisia; to look for risk factors; and to evaluate socioeconomic costs.
Data on a cross-section of 5000 individuals aged 15 years or older living in Monastir were collected by interviewers using a previously developed 51-item questionnaire.
The study participation rate was 87.6%. The annual prevalence of DRS was 2.21% and the incidence was 1.44%. Among the patients with DRS, 94.8% received healthcare interventions, 64% had plain radiographs taken, and 45.4% underwent computed tomography of the lumbar spine. Sick leaves were given to 77.7% of patients, and mean sick leave duration was 9 weeks. A change in job was required in 5.5% of cases. Factors associated with DRS included male gender (P<0.001), obesity (P<0.0001), smoking (P<0.0001), a history of low back problems (P<0.0001), anxiety and depression (P<0.0001), a job requiring prolonged standing and bending forward (P<0.03), heavy manual labor (P<0.005), heavy lifting (P<0.0001), and exposure to vibrations (P<0.0001).
The prevalence of DRS in Monastir is 2.2%. We identified a number of patient- and occupation-related risk factors. The high socioeconomic cost should encourage preventive measures.
Both clinical and epidemiologic studies have shown an association between atherosclerotic changes in the aorta or lumbar arteries and lumbar disc degeneration. However, the association between atherosclerosis and sciatica remains unknown. The aim of this study was to investigate the association between carotid intima-media thickness and sciatica.
The target population consisted of people aged 45 to 74 years, who had participated in a Finnish nationwide population study during the period 2000 to 2001 and lived within 200 km of the 6 study clinics. Of the 1867 eligible subjects, 1386 (74%) were included in the study. We used high-resolution B-mode ultrasound imaging to measure intima-media thickness, and local or radiating low back pain was determined by a standard interview and clinical signs of sciatica through a physician's clinical examination.
Carotid intima-media thickness was associated with continuous radiating low back pain and with a positive unilateral clinical sign of sciatica among men only. After adjustment for potential confounders, each standard deviation (0.23 mm) increment in carotid intima-media thickness showed an odds ratio of 1.6 (95% confidence interval 1.1-2.3) for continuous radiating low back pain and 1.7 (95% confidence interval 1.3-2.1) for a positive unilateral clinical sign of sciatica. Carotid intima-media thickness was not associated with local low back pain.
Sciatica may be a manifestation of atherosclerosis, or both conditions may share common risk factors.
Atherosclerosis of arteries supplying the lumbar region has been suggested as a mechanism leading to intervertebral disc degeneration and sciatica. The study described here examined whether serum lipid levels or pharmacologically treated hyperlipidemia were associated with sciatica.
A nationally representative sample (n=8028) of Finns aged 30 years or over was interviewed and examined. Sciatica was assessed by a physician according to preset criteria. Information for the present purpose was available for 74.8% of the sample.
The prevalence of sciatica was 3.3% for men and 2.2% for women. In men without hyperlipidemia treatment, sciatica was associated with total cholesterol (high vs. low tertile: OR 2.28, 95% CI 1.14-4.55), LDL cholesterol (2.12; 1.11-4.05), and triglycerides (1.92; 1.04-3.55), adjusted for age, BMI, exercise, smoking, heavy physical work, and education. HDL was not associated with sciatica. For men in the highest tertile of both total cholesterol and triglycerides, the OR of sciatica was 3.89 (1.68-8.99) in comparison to men with cholesterol in the lowest tertile and triglycerides in the lowest or the middle tertile. In similar analyses among women no associations were seen. Pharmacologically treated hyperlipidemia was associated with sciatica in women (2.02; 1.01-4.04), but not in men (1.71; 0.83-3.55).
Independent of BMI and other possible confounders, clinically assessed sciatica in men was associated with levels of atherogenic serum lipids. Pharmacologically treated hyperlipidemia was associated with sciatica in women. The findings are in accordance with the atherosclerosis-sciatica hypothesis.
Physical activity (PA) begins to decline in adolescence with a concomitant increase in weight. We hypothesized that a vicious circle may arise between decreasing PA and weight gain from adolescence to early adulthood.
PA and self-perceived physical fitness assessed in adolescents (16-18 years of age) were used to predict the development of obesity (BMI > or =30 kg/m(2)) and abdominal obesity (waist >/=88 cm in females and > or =102 cm in males) at age 25 in 4,240 twin individuals (90% of twins born in Finland, 1975-1979). Ten 25-year-old monozygotic (MZ) twin pairs who were discordant for obesity (with a 16 kg weight difference) were then carefully evaluated for current PA (using a triaxial accelerometer), total energy expenditure (TEE, assessed by means of the doubly labeled water (DLW) method), and basal metabolic rate (BMR, assessed by indirect calorimetry).
Physical inactivity in adolescence strongly predicted the risk for obesity (odds ratio (OR) 3.9, 95% confidence interval (CI) 1.4-10.9) and abdominal obesity (4.8, 1.9-12.0) at age 25, even after adjusting for baseline and current BMI. Poor physical fitness in adolescence also increased the risk for overall obesity (5.1, 2.0-12.7) and abdominal obesity (3.2, 1.5-6.7) in adulthood. Physical inactivity was both causative and secondary to the development of obesity discordance in the MZ pairs. TEE did not differ between the MZ co-twins. PA was lower whereas BMR was higher in the obese co-twins.
Physical inactivity in adolescence strongly and independently predicts total (and especially) abdominal obesity in young adulthood, favoring the development of a self-perpetuating vicious circle of obesity and physical inactivity. Physical activity should therefore be seriously recommended for obesity prevention in the young.
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- L Kaila-Kangas
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Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated
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Adipose tissue, inflammation, and cardiovascular disease
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Berg AH, Scherer PE. Adipose tissue, inflammation, and cardiovascular disease. Circ Res. 2005;96:939-949.
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