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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.
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Systematic Reviews and Meta- and Pooled Analyses
Obesity as a Risk Factor for Sciatica: A Meta-Analysis
Rahman Shiri*, Tea Lallukka, Jaro Karppinen, and Eira Viikari-Juntura
*Correspondence to Dr. Rahman Shiri, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland
(e-mail: rahman.shiri@ttl.fi).
Initially submitted October 29, 2013; accepted for publication January 7, 2014.
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 sciaticawas 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.
back pain; hospitalization; intervertebral disc displacement; obesity; overweight; sciatica
Abbreviations: BMI, body mass index; CI, confidence interval; OR, odds ratio.
Low back pain is the number 1 debilitating condition glob-
ally, and in 2010 it contributed 10.7% to the total number of
years lived with disability (1). Among low back disorders,
sciatica and lumbar disc herniation are the most persistent
and disabling conditions (2). Lumbar radicular pain is de-
ned as low back pain radiating to the leg below the knee
level, while sciatica is dened as lumbar radicular pain along
with clinical ndings suggestive of nerve root compression
(2,3). Sciatica is usually caused by compression or irritation
of one of the lumbosacral nerve roots, often due to derange-
ment of a lumbar intervertebral disc such as lumbar disc her-
niation (4), although other causes for sciatica have also been
reported (5).
The prevalence of lumbar radicular pain during the preced-
ing 12 months ranges between 13% and 36% (68) and that
of clinically dened sciatica between 2% and 5% (911). The
incidence of lumbar radicular pain increases with age, where-
as that of nonspecic low back pain tends to decrease with
age (12). Lumbar radicular pain and sciatica have poorer
prognoses than nonspecic low-back-pain syndromes, and
they can cause prolonged work disability (2,13).
The etiologies of lumbar radicular pain and sciatica are not
well known, but they seem to be multifactorial. Known risk
factors for lumbar radicular pain and sciatica include occupa-
tional workload, such as carrying heavy items, bending, or
kneeling (14,15), and body height (16,17). Lifestyle risk fac-
tors have also been suggested as possible risk factors for lum-
bar radicular pain and sciatica (18).
Obesity is a prevalent public health problem and is associ-
ated with various outcomesin addition to cardiovascular
diseases, obesity has recently been associated with musculo-
skeletal disorders (18,19). Previously we conducted a sys-
tematic review on the associations of weight-related factors
with lumbar radicular pain and sciatica (18). Based on a qual-
itative assessment of 13 studies, we found associations of
weight-related factors with lumbar radicular pain or sciatica
929 Am J Epidemiol. 2014;179(8):929937
American Journal of Epidemiology
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Vol. 179, No. 8
DOI: 10.1093/aje/kwu007
Advance Access publication:
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in 1 out of 4 cross-sectional studies, 3 out of 4 case-control
studies, and 3 out of 5 cohort studies. Thus, so far it is un-
known whether only obesity is associated with lumbar radic-
ular pain and sciatica or both overweight and obesity are
associated. We also performed a meta-analysis on the rela-
tionships of overweight and obesity with nonspeciclow
back pain (19). Both overweight and obesity were associated
with an increased risk of nonspecic low back pain.
So far, the roles of overweight and obesity in lumbar radic-
ular pain or sciatica, as more specic or objectively assessed
outcomes, have not been addressed with a meta-analysis. Our
aim was to carryout a meta-analysis to estimate the magnitude
of the associations of overweight and obesity with lumbar ra-
dicular pain and/or sciatica. To include studies published after
our qualitative review, a period comprising the past 8 years, we
updated our search and reassessed the previous studies regard-
ing their eligibility for the meta-analysis.
METHODS
Search strategy
We conducted comprehensive literature searches in
PubMed, Embase, Scopus, and Web of Science using prede-
ned keywords (lumbar radicular pain or sciatic pain or sci-
atic syndrome or lumbosciatic syndrome or lumbosacral
radicular syndrome or sciatica or intervertebral disk displace-
ment or disc herniation or herniated lumbar disc or prolapsed
lumbar disc or disc protrusion or herniated nucleus pulposus or
spinal diseases or back pain or back disorders) and (BMI
or body mass index or overweight or underweight or obesity
or body weight or waist circumference or waist hip ratio). We
used both Medical Subject Headings and text words in
PubMed, and we used Emtree terms and text words in Em-
base. We included all languages, even though we did not
identify any eligible non-English paper. We excluded case re-
ports, reviews, guidelines, editorials, and letters. We checked
the reference lists of included articles for additional studies.
We looked at the full text of studies on the associations of
smoking and physical activity/inactivity with lumbar radicu-
lar pain or sciatica for additional studies on weight-related
factors (18). Moreover, we looked at the full text of studies
on the associations of overweight/obesity, smoking, and
physical activity/inactivity with low back pain to identify ad-
ditional studies on lumbar radicular pain or sciatica (19,20).
Selection of the studies
The rst author (R.S.) assessed the titles, abstracts, and full
texts of the studies found and investigated whether the studies
examined the associations of weight-related factors with lum-
bar radicular pain or sciatica. We included cross-sectional
and cohort studies as well as both population-based and
hospital-based case-control studies in the systematic review.
To be eligible for a meta-analysis, the studies had to report
quantitative data on the association between overweight/obe-
sity and lumbar radicular pain or sciatica. We also contacted
several authors (16,2125) for additional information or re-
sults. Some of them (16,22,25) provided additional informa-
tion or new results.
Quality assessment
Two reviewers (R.S. and T.L.) independently assessed the
quality of the studies using the Effective Public Health Prac-
tice Project tool for observational studies (26). Summary
quality scores may provide a useful overall assessment. How-
ever, the scales are not recommended for assessment of the
quality of studies in systematic reviews (27). Therefore, we
assessed 5 main domains: selection bias, performance bias,
detection bias, confounding, and attrition bias (see Web Table 1,
available at http://aje.oxfordjournals.org/). Studies conducted
among volunteers, studies that included patients with lumbar
radicular pain or sciatica without acontrol group, studies with
a response rate less than 50%, and studies not reporting quan-
titative results that could be used to estimate odds ratios were
excluded from the meta-analysis. Disagreements between the
2 reviewers were resolved by consensus.
Meta-analysis
We used World Health Organization recommended cutoff
points for body mass index (BMI; weight (kg)/height (m)
2
)
and dened overweight as BMI 2529.9 and obesity as BMI
30 (28,29). We performed meta-analyses for overweight or
obesity and dened it as BMI 25. We also included studies
that reported an estimate for BMI 24 (30) or >24.3 (31) for
overweight/obesity or an estimate for BMI >27.5 (32), 28
(30,33), or 29 (31,34,35) for obesity. One study conducted
among adolescents dened overweight or obesity by using
internationally acceptable age-specic and sex-specic cut-
off points for BMI (36), and it was also included in the
meta-analysis.
For studies that analyzed BMI as a continuous variable
(1-unit increase in BMI), we estimated the effect size by
multiplying the log odds ratio by 5 for overweight and by
10 for obesity. For 1 study (37) that reported an estimate for
a 1-standard-deviation increase in BMI, we estimated the effect
size by dividing the log odds ratio by the standard deviation and
then multiplying by 5 for overweight and by 10 for obesity.
We pooled the estimates for the subgroups of BMI to ob-
tain an overall estimate for overweight or obesity. We also
pooled the estimates for subgroups of the study population
(e.g., men and women) to obtain an estimate for the total study
population. We calculated a new estimate for overweight or
obese subjects for studies that compared normal, overweight,
or obese people with underweight subjects (31,3335). For
these studies, we calculated standard errors from the natural
logarithm of the condence intervals, divided the relative
risk/odds ratio for overweight or obesity by the relative risk/
odds ratio for normal weight, and then estimated new con-
dence intervals for the obtained relative risk/odds ratio.
For studies that reported mean BMI in participants with or
without sciatica, we calculated the standardized mean differ-
ence by dividing the difference between 2 mean values by the
pooled standard deviation. We then converted the standard-
ized mean difference to an odds ratio (38).
One cross-sectional study (39) did not report a condence
interval for the estimate. We calculated the standard error
(SE) of the estimate from this study using the following for-
mula: SE = log(odds ratio)/Zvalue (40).
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We used a random-effects meta-analysis. The estimate
from a random-effects meta-analysis is more conservative
than that from a xed-effect meta-analysis (40). Similar re-
sults were reported from cross-sectional, case-control, and
cohort studies (Table 1). Therefore, we combined all designs
in a single analysis. Four cohort studies reported the relative
risk of hospitalization or surgery due to lumbar disc hernia-
tion (16,33,35,41) for overweight or obese subjects. Since
the incidence rate of lumbar disc herniation was below 1% in
those studies, the odds ratios and relative risks were identical.
Thus, we did not convert the relative risks to odds ratios.
We assessed the presence of heterogeneity across the studies
by means of the I
2
statistic (42). The I
2
statistic shows the total
variation across studies that is not due to chance. An I
2
statistic
less than 25% indicates a small amount of inconsistency, and
more than 50% indicates a large amount of inconsistency (43).
We used meta-regression to determine whether study-level co-
variates accounted for the observed heterogeneity (44).
To assess publication bias, we used a funnel plot, which
compared the sizes of the overweight/obesity effects with
their standard errors. We used the Egger regression test to ex-
amine funnel plot asymmetry and the trim-and-ll method to
explore the number of missing studies due to publication bias
(45,46). Statistical signicance for publication bias was
based on a Pvalue less than 0.10 (47). We used Stata, version
10 (StataCorp LP, College Station, Texas), for meta-analysis.
RESULTS
Our searches initially identied 5,303 abstracts (Web
Figure 1). The rst author (R.S.) looked at the full text of
491 relevant study reports on the associations between weight-
related factors and low back pain or lumbar disc disorders.
There were 43 relevant studies on the associations of weight-
related factors with lumbar radicular pain or sciatica. We ex-
cluded 12 studies conducted among patient populations that
did not have a control group, 2 studies on volunteers, 2 stud-
ies with no quantitative data for estimation of the odds ratio,
and 1 study with a response rate of 40%. Finally, we included
8 cross-sectional studies, 7 case-control studies, and 11 co-
hort studies on the association between BMI and lumbar ra-
dicular pain or sciatica in the meta-analysis (Web Table 2).
Of the 26 studies included in this meta-analysis, 8 studies
were on lumbar radicular pain (68,25,30,34,37,48),
Table 1. Associations of Study Design, Sex, and Methodological Quality With the Size of the Relationship Between Overweight or Obesity and
Lumbar Radicular Pain or Sciatica (Sensitivity Analysis) in 26 Studies Included in a Meta-Analysis, 19662013
Study Characteristic
Overweight Overweight or Obesity Obesity
No. of
Studies OR 95% CI I
2
,% No. of
Studies OR 95% CI I
2
,% No. of
Studies OR 95% CI I
2
,%
Total 17 1.17 1.12, 1.22 0 25 1.32 1.19, 1.46 86.9 19 1.36 1.25, 1.48 32.2
Study design
Cross-sectional 5 1.15 1.06, 1.25 0 6 1.20 1.12, 1.28 1.6 7 1.37 1.21, 1.56 23.4
Case-control 3 1.15 1.02, 1.30 17.1 7 1.45 1.05, 2.00 95.4 3 1.34 1.17, 1.54 0
Cohort 9 1.19 1.12, 1.25 0 12 1.26 1.16, 1.38 47.7 9 1.40 1.18, 1.65 50.4
Sex of participants
Men 9 1.24 1.15, 1.33 0 13 1.26 1.18, 1.34 0 10 1.37 1.21, 1.54 0
Women 9 1.15 1.09, 1.22 0 13 1.23 1.14, 1.33 37.3 9 1.33 1.19, 1.49 36.6
Confounding
Weak 10 1.15 1.10, 1.21 0 12 1.19 1.13, 1.25 23.3 10 1.30 1.18, 1.43 30.9
Moderate/strong 7 1.23 1.12, 1.35 0 13 1.43 1.16, 1.77 90.6 9 1.47 1.28, 1.69 16.2
Selection bias
Weak 7 1.16 1.08, 1.25 22.0 11 1.47 1.18, 1.82 94.1 8 1.48 1.21, 1.82 69.0
Moderate/strong 10 1.18 1.11, 1.25 0 14 1.23 1.17, 1.28 0 11 1.36 1.25, 1.47 0
Performance bias
Weak 7 1.18 1.11, 1.25 0 10 1.39 1.12, 1.73 93.6 7 1.35 1.22, 1.50 0
Moderate/strong 10 1.16 1.09, 1.23 3.6 15 1.22 1.14, 1.31 37.6 12 1.40 1.23, 1.59 50.3
Detection bias
Weak 8 1.14 1.07, 1.21 0 16 1.34 1.13, 1.58 90.8 8 1.34 1.21, 1.48 0
Moderate/strong 9 1.19 1.12, 1.26 0 9 1.25 1.16, 1.36 45.9 11 1.41 1.24, 1.60 49.3
Attrition bias
Weak 11 1.16 1.10, 1.23 15.4 17 1.36 1.18, 1.56 91.2 13 1.38 1.23, 1.55 51.7
Moderate/strong 6 1.20 1.09, 1.32 0 8 1.25 1.16, 1.34 0 6 1.37 1.22, 1.55 0
Abbreviations: CI, confidence interval; OR, odds ratio.
Obesity and Sciatica 931
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7 were on clinically dened sciatica (911,35,39,49,50),
8 were on hospitalization due to sciatica (16,17,22,23,
3133,51), and 4 were on surgery due to lumbar disc herni-
ation (22,24,41,52). One study (22) assessed the association
of overweight with hospitalization due to sciatica, as well as
surgery due to lumbar disc herniation. Of the 26 studies in-
cluded in the review, 17 studies reported results for over-
weight, 25 reported results for overweight/obesity, and 19
reported results for obesity.
Overweight/obesity and lumbar radicular pain or sciatica
The pooled odds ratio for lumbar radicular pain was 1.23
(95% condence interval (CI): 1.14, 1.33; I
2
=0%; n=
19,165) for overweight and 1.40 (95% CI: 1.27, 1.55; I
2
=
0%; n= 19,165) for obesity (Figure 1). The pooled odds
ratio for physician-diagnosed sciatica was 1.12 (95% CI:
1.04, 1.20; I
2
=0%; n= 109,724) for overweight and 1.31
(95% CI: 1.07, 1.62; I
2
= 63.9%; n= 115,661) for obesity
(Figure 2).
The odds ratio for hospitalization due to sciatica was 1.16
(95% CI: 1.09, 1.24; I
2
=0%;n= 358,328) for overweight
and 1.38 (95% CI: 1.23, 1.54; I
2
=0%; n= 358,328) for
obesity (Figure 3). For surgery due to lumbar disc herniation,
the studies reported estimates only for overweight/obesity
(Figure 3). The pooled odds ratio was 1.89 (95% CI: 1.25,
2.86; I
2
= 79.7%; n= 73,982).
Heterogeneity and meta-regression
In this meta-analysis, the estimates of studies on the asso-
ciation between obesity and clinically dened sciatica were
moderately heterogeneous (I
2
= 63.9%; Figure 2), and those
of studies on the association between overweight/obesity and
surgery due to lumbar disc herniation were highly heteroge-
neous (I
2
= 79.7%; Figure 3).
Overweight
Riihimäki, 1989 (30)
Manninen, 1995 (37)
Lean, 1999 (6)
Miranda, 2001 (34)
Leino-Arjas, 2006 (48)
Kääriä, 2011 (7)
Karjalainen, 2013 (25)
Shiri, 2013 (8)
Subtotal (I2= 0.0%, P= 0. 773)
Overweight or Obesity
Riihimäki, 1989 (30)
Manninen, 1995 (37)
Lean, 1999 (6)
Miranda, 2001 (34)
Leino-Arjas, 2006 (48)
Kääriä, 2011 (7)
Shiri, 2013 (8)
Karjalainen, 2013 (25)
Subtotal (I2= 7.3%, P= 0. 374)
Obesity
Riihimäki, 1989 (30)
Manninen, 1995 (37)
Lean, 1999 (6)
Miranda, 2001 (34)
Leino-Arjas, 2006 (48)
Kääriä, 2011 (7)
Karjalainen, 2013 (25)
Shiri, 2013 (8)
Subtotal (I2= 0.0%, P= 0.759)
1.10 (0.60, 2.10)
0.96 (0.34, 2.77)
1.23 (1.10, 1.37)
1.08 (0.79, 1.38)
1.91 (1.11, 3.30)
1.27 (1.11, 1.45)
1.15 (0.80, 1.65)
1.30 (0.80, 1.90)
1.23 (1.14, 1.33)
1.31 (0.82, 2.07)
0.96 (0.38, 2.43)
1.26 (1.15, 1.38)
1.21 (0.98, 1.43)
2.12 (1.43, 3.16)
1.31 (1.17, 1.45)
1.40 (0.99, 1.98)
1.19 (0.86, 1.64)
1.29 (1.20, 1.38)
1.60 (0.80, 3.10)
0.93 (0.12, 7.68)
1.34 (1.15, 1.56)
1.42 (1.07, 1.76)
2.39 (1.34, 4.27)
1.38 (1.15, 1.66)
1.33 (0.65, 2.74)
1.60 (0.90, 2.80)
1.40 (1.27, 1.55)
ES (95% CI) Weight
1.10 (0.60, 2.10)
0.96 (0.34, 2.77)
1.23 (1.10, 1.37)
1.08 (0.79, 1.38)
1.91 (1.11, 3.30)
1.27 (1.11, 1.45)
1.15 (0.80, 1.65)
1.30 (0.80, 1.90)
1.23 (1.14, 1.33)
1.60 (0.80, 3.10)
0.93 (0.12, 7.68)
1.34 (1.15, 1.56)
1.42 (1.07, 1.76)
2.39 (1.34, 4.27)
1.38 (1.15, 1.66)
1.33 (0.65, 2.74)
1.60 (0.90, 2.80)
1.40 (1.27, 1.55)
, %
0.125 0.25 0.5 1.0 2.0 4.0 8.0
Odds Ratio
First Author, Year (Reference No.)
1.49
0.54
47.82
7.53
1.97
33.05
4.47
3.13
2.18
0.54
42.09
12.07
2.91
32.05
3.80
4.36
100.00
2.18
0.23
43.04
16.16
2.97
30.38
1.93
3.11
100.00
1.49
0.54
47.82
7.53
1.97
33.05
4.47
3.13
100.00
2.18
0.54
42.09
12.07
2.91
32.05
3.80
4.36
2.18
0.23
43.04
16.16
2.97
30.38
1.93
3.11
100.00
Figure 1. Results of a meta-analysis of the association of overweight or obesity with lumbar radicular pain, 19662013. The size of the gray
shaded area indicates the weight of each study. Horizontal lines show the 95% confidence intervals (CIs). ES, effect size.
932 Shiri et al.
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In the meta-regression of the 25 studies on the association
between overweight/obesity and lumbar radicular pain or
sciatica, the heterogeneity across studies was signicantly
related to the type of outcome. The heterogeneity was not
explained by study design, selection bias, performance bias,
detection bias, attrition bias, or adjustment for potential con-
founders. Moreover, heterogeneity was not related to the use
of BMI as a continuous variable or the use of BMI as a cat-
egorical variable with 2, 3, or more categories.
After the exclusion of 1 study (11) from the meta-analysis on
the association between obesity and clinically dened sciatica,
the variation across studies disappeared and the I
2
statistic
dropped from 63.9% to 0%. For surgery due to lumbar disc her-
niation, the I
2
statistic also dropped from 79.7% to 0% when 2
case-control studies conducted in adults (24,52) (pooled OR =
2.57, 95% CI: 2.28, 2.88; I
2
= 0%) were analyzed separately
from 2 cohort studies conducted in adolescents (22,41) ( pooled
OR = 1.39, 95% CI: 1.03, 1.87; I
2
=0%).
Sensitivity analysis
In stratied analyses of all outcomes combined (Table 1),
the effect sizes were smaller in the studiesthat controlled their
estimates for potential confounders than in studies that re-
ported unadjusted estimates or controlled their estimates for
a few confounders only. In separate meta-analyses of differ-
ent outcomes, only the odds ratio for physician-diagnosed
sciatica among obese persons was attenuated in the studies
that controlled for potential confounders ( for overweight,
OR = 1.11, 95% CI: 1.03, 1.20 (I
2
= 0%); for obesity, OR =
1.13, 95% CI: 1.02, 1.24 (I
2
=0%)) (9,35). The estimates
were similar for lumbar radicular pain (overweight: OR =
1.22, 95% CI: 1.09, 1.36 (I
2
= 0%); obesity: OR = 1.39,
95% CI: 1.21, 1.61 (I
2
=0%))(7,25,34,37) and hospitaliza-
tion due to sciatica (overweight: OR = 1.16, 95% CI: 1.07,
1.27 (I
2
= 19%); obesity: OR =1.40, 95% CI: 1.22, 1.61 (I
2
=
14.3%)) (16,17,23,32).
The associations of both overweight and obesity with lum-
bar radicular pain or sciatica were similar in men and women.
The pooled odds ratio for obesity was 1.37 (95% CI: 1.21,
1.54) in men and 1.33 (95% CI: 1.19, 1.49) in women. The
effect sizes were similar according to study design and accord-
ing to the presence or absence of selection bias, performance
bias, detection bias, and attrition bias. Slight variation in the
effect sizes between different types of study designs was due
to the unequal distribution of the different types of outcomes.
Overweight
Heliövaara, 1991 (9)
Jhawar, 2006 (35)
Leino-Arjas, 2008 (10)
Subtotal (I2= 0.0%, P= 0. 598)
Overweight or Obesity
Heliövaara, 1991 (9)
Toda, 2000 (50)
Kostova, 2001 (49)
Jhawar, 2006 (35)
Leino-Arjas, 2008 (10)
Subtotal (I2= 0.0%, P= 0. 731)
Obesity
Heliövaara, 1991 (9)
Videman, 1995 (39)
Jhawar, 2006 (35)
Younes, 2006 (11)
Leino-Arjas, 2008 (10)
Subtotal (I2= 63.9%, P= 0.026)
1.05 (0.89, 1.18)
1.14 (1.04, 1.24)
1.20 (0.80, 1.79)
1.12 (1.04, 1.20)
1.06 (0.93, 1.20)
0.97 (0.60, 1.58)
1.32 (0.81, 2.18)
1.13 (1.05, 1.21)
1.24 (0.91, 1.68)
1.12 (1.06, 1.19)
1.10 (0.80, 1.40)
1.40 (1.00, 1.80)
1.13 (1.01, 1.25)
2.27 (1.48, 3.52)
1.29 (0.80, 2.08)
1.31 (1.07, 1.62)
Weight, %
1.06 (0.93, 1.20)
0.97 (0.60, 1.58)
1.32 (0.81, 2.18)
1.13 (1.05, 1.21)
1.24 (0.91, 1.68)
1.12 (1.06, 1.19)
1.10 (0.80, 1.40)
1.40 (1.00, 1.80)
1.13 (1.01, 1.25)
2.27 (1.48, 3.52)
1.29 (0.80, 2.08)
1.31 (1.07, 1.62)
1
0.125 0.25 0.5 1.0 2.0 4.0 8.0
Odds Ratio
ES (95% CI)
First Author, Year (Reference No.)
69.30
3.35
100.00
21.35
1.48
1.42
72.07
3.69
100.00
21.37
20.56
31.80
13.93
12.34
100.00
21.35
1.48
1.42
72.07
3.69
100.00
21.37
20.56
31.80
13.93
12.34
100.00
27.34
Figure 2. Results of a meta-analysis of the association of overweight or obesity with physician-diagnosed sciatica, 19662013. The size of the
gray shaded area indicates the weight of each study. Horizontal lines show the 95% confidence intervals (CIs). ES, effect size.
Obesity and Sciatica 933
Am J Epidemiol. 2014;179(8):929937
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Publication bias
The pooled odds ratio from 26 studies on overweight/
obesity (7 studies) or obesity (19 studies) was 1.45 (95% CI:
1.26, 1.66). The funnel plot of data from the 26 studies in-
cluded in the meta-analysis was symmetrical (Figure 4). The
Pvalue for the Egger test was 0.107. No missing study due to
publication bias was imputed using the trim-and-ll method.
DISCUSSION
This meta-analysisshowed that both overweight andobesity
are consistently associated with an increased risk of lumbar ra-
dicular pain and sciatica, with a dose-response relationship
among both men and women.
We studied a wide range of outcomes, from self-reported
symptoms to objectively assessed outcomes such as clinically
veried sciatica with nerve root entrapment, hospitalization,
and surgery due to lumbar disc herniation. Although self-
reported radicular pain is a subjective outcome, we consid-
ered it clinically relevant, since it is associated with poorer
quality of life, more functional limitations, and increased
use of health-care services compared with nonspeciclow
back pain (53). We found consistent results for all outcomes.
The associations of overweight and obesity with lumbar ra-
dicular pain and sciatica were modest. The strengths of the
associations were similar to those for nonspecic low back
pain (19).
There were sex differences in the prevalence, incidence,
and recovery rates of our outcomes of interest; for example,
Overweight and Hospitalization
Heliövaara, 1987 (17)
Vessey, 1999 (33)
Kaila-Kangas, 2003 (32)
Leino-Arjas, 2004 (23)
Schumann , 2010 (31 )
Wahlström, 2012 (16)
Subtotal (I2= 0.0%, P= 0.440)
Over weigh t or Obesit y a nd H ospitaliz ation
Heliövaara, 1987 (17)
Vessey, 1999 (33)
Kaila-Kangas, 2003 (32)
Leino-Arjas, 2004 (23)
Zhang, 2009 (5 1)
Schumann , 2010 (31 )
Rivinoja, 2011 (22)
Wahlström, 2012 (16)
Subtotal (I2= 22.7%, P= 0.249)
Obesity and Hospitalization
Heliövaara, 1987 (17)
Vessey, 1999 (33)
Kaila-Kangas, 2003 (32)
Leino-Arjas, 2004 (23)
Schumann , 2010 (31 )
Wahlström, 2012 (16)
Subtotal (I2= 0.0% , P= 0.501)
Over weigh t or Obes ity and Surg er y
Böstman, 1993 (52)
Saftic, 2006 (24)
Mattila, 2 008 (41)
Rivinoja, 2011 (22)
Subtotal (I2= 79.7%, P= 0.002)
1.28 (0.99, 1.61)
1.02 (0.68, 1.35)
1.92 (0.84, 4.36)
1.08 (0.96, 1.22)
1.29 (0.98, 1.71)
1.19 (1.08, 1.31)
1.16 (1.09, 1.24)
1.33 (1.04, 1.62)
1.02 (0.73, 1.32)
2.25 (1.23, 4.10)
1.16 (1.05, 1.27)
1.12 (0.96, 1.29)
1.35 (1.08, 1.69)
1.13 (0.78, 1.64)
1.23 (1.13, 1.35)
1.20 (1.12, 1.29)
1.63 (0.99, 2.59)
1.04 (0.45, 1.63)
2.69 (1.12, 6.45)
1.30 (1.12, 1.52)
1.47 (1.00, 2.15)
1.45 (1.18, 1.78)
1.38 (1.23, 1.54)
2.56 (2.28, 2.88)
2.77 (1.05, 4.49)
1.52 (1.04, 2.21)
1.19 (0.73, 1.94)
1.89 (1.25, 2.86)
1.28 (0.99, 1.61)
1.02 (0.68, 1.35)
1.92 (0.84, 4.36)
1.08 (0.96, 1.22)
1.29 (0.98, 1.71)
1.19 (1.08, 1.31)
1.16 (1.09, 1.24)
1.33 (1.04, 1.62)
1.02 (0.73, 1.32)
2.25 (1.23, 4.10)
1.16 (1.05, 1.27)
1.12 (0.96, 1.29)
1.35 (1.08, 1.69)
1.13 (0.78, 1.64)
1.23 (1.13, 1.35)
1.20 (1.12, 1.29)
1.63 (0.99, 2.59)
1.04 (0.45, 1.63)
2.69 (1.12, 6.45)
1.30 (1.12, 1.52)
1.47 (1.00, 2.15)
1.45 (1.18, 1.78)
1.38 (1.23, 1.54)
2.56 (2.28, 2.88)
2.77 (1.05, 4.49)
1.52 (1.04, 2.21)
1.19 (0.73, 1.94)
1.89 (1.25, 2.86)
Weight, %
10.125 0.25 0.5 1.0 2.0 4.0 8.0
Odds Ratio
ES (95% CI)ES (95% CI)
33.37
7.81
3.93
0.68
32.17
5.84
49.57
100.00
8.30
4.95
1.28
28.05
15.89
8.00
3.25
30.28
100.00
5.31
2.96
1.60
52.65
8.42
29.05
100.00
16.72
26.73
23.18
100.00
First Author, Year (R eference No.)
Figure 3. Results of a meta-analysis of the associations of overweight, overweight/obesity, and obesity with hospitalization due to sciatica and of
the association of overweight/obesity with surgery due to sciatica, 19662013. The size of the grayshaded area indicates theweight of each study.
Horizontal lines show the 95% confidence intervals (CIs). ES, effect size.
934 Shiri et al.
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self-reported lumbar radicular pain is more prevalent among
women (25), and they seem to experience slower recovery
from severe sciatica (54), while men have a higher incidence
of hospitalization and surgery due to sciatica (22,55). How-
ever, our meta-analysis showed no sex difference in the asso-
ciation between overweight/obesity and lumbar radicular
pain or sciatica. A previous meta-analysis on the associations
between obesity and nonspecic low back pain showed stron-
ger associations for women than for men (19). Differences
between age groups in the associations of overweight and
obesity with lumbar radicular pain and sciatica may also
exist. However, the studies included in this meta-analysis
did not report any age-specic results.
The mechanisms by which obesity increases the risk of
lumbar radicular pain and sciatica are not known. Obesity
contributes to the development of chronic, low-grade inam-
mation through release of inammatory mediators from excess
adipose tissue (56). Obesity-related chronic inammation may
lead to the developmentof sciatica or the persistence of sciatica
symptoms. Leptin is one of the adipocyte-derived adipokines,
and high serum leptin levels are associated with obesity and
with the development of knee osteoarthritis independently of
BMI (57). Leptin is suspected to be involved in reorganizing
the cytoskeleton of nucleus pulposus cells (58), but the role of
fat tissue-derived leptin in the association between obesity and
sciatica is not known.
Obesity may slow down the healing of a disc injury. In a
large trial of patients with sciatica (59), obese patients had less
improvement in their back-related disability than nonobese
patients. The slower recovery was observed irrespective of
the type of treatment (i.e., conservative or surgical). More-
over, obesity increases the risk of recurrent disc herniation
after lumbar microdiscectomy (60).
Obesity may also interfere with the nutrition of the inter-
vertebral discs, leading to an impaired healing process. In a
3-year follow-up study of sciatica patients (61), BMI was
the strongest predictor of incident lumbar artery occlusion,
which also suggests that impairment of nutrition can be one
of the pathways of obesitys relationship with sciatica.
The results of any meta-analysis depend on the data from
the original studies, and publication bias can distort the ndings.
There was no evidence of publication bias, however. Small
studies on lumbar radicular pain or sciatica with nonsigni-
cant results for overweight/obesity have been published due
to the fact that the main aim in many of those studies was not
to examine the relationship of overweight/obesity with lum-
bar radicular pain or sciatica. Overweight/obesity in these
studies was used as a covariate for adjustment purposes. Fur-
thermore, the associations of overweight and obesity with
lumbar radicular pain or sciatica may have been under-
estimated in studies that did not use the World Health
Organization-recommended BMI cutoff points to dene
overweight and obesity.
Our sensitivity analyses showed that the ndings of this
meta-analysis are robust. The observed association between
overweight/obesity and sciatica did not differ between men
and women and was independent of the designs and response
rates of the included studies, as well as of the assessment
method used for weight and height (self-reported or mea-
sured). Moreover, the associations of overweight/obesity
with lumbar radicular pain and hospitalization due to sciatica
appeared not to be confounded. Exclusion of the studies that
did not control for potential confounders attenuated the asso-
ciation of obesity with clinically dened sciatica only. How-
ever, the subgroup analysis for clinically dened sciatica had
low statistical power because only 2 studies controlled their
estimates for potential confounders.
In conclusion, the ndings of this study consistently show
that both overweight and obesity are risk factors for lumbar
radicular pain and sciatica, with a dose-response relationship
among both men and women.
ACKNOWLEDGMENTS
Author afliations: Centre of Expertise for Health and
Work Ability, Finnish Institute of Occupational Health, Hel-
sinki, Finland (Rahman Shiri, Tea Lallukka, Jaro Karppinen);
Disability Prevention Centre, Finnish Institute of Occupational
Health, Helsinki, Finland (Rahman Shiri, Tea Lallukka, Eira
Viikari-Juntura); and Medical Research Center Oulu, Oulu
University Hospital and University of Oulu, Oulu, Finland
(Jaro Karppinen).
We thank Drs. Bengt Järvholm (16) and Markus Paananen
(22) for providing us with new results.
Conict of interest: none declared.
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... Consistent guidelines for acute LBP feature early and gradual advice to stay active and avoid prescribing bed rest, while common guidelines for the management of chronic LBP includes supervised exercises, cognitive behavioural therapy, and self-management strategies [6]. In addition to the emphasis on exercise, recent studies suggest that lifestyle modifications should be integrated into LBP management programs [7][8][9]. ...
... There is a growing number of studies suggesting an association between being overweight/obese and having LBP [7,8,[10][11][12]. Multiple studies have found that after controlling for potential confounders (e.g., age, sex), the prevalence of LBP is significantly increased in the presence of a high body mass index (BMI) [10,12,13]. ...
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Background Lumbar disc herniation (LDH) is not a common condition in children. Most reports on pediatric LDH concern the outcomes of surgeries performed in children in whom nonsurgical treatment failed while the outcome of nonsurgical treatment of LDH in children was rarely reported. Cases presentation Case 1: a 10-year-old girl presented with back pain and sciatica in her left leg for over 3 months. The physical examination revealed exacerbation of back pain by waist extension or flexion, and a positive Lasegue’s sign was revealed in her left leg. Magnetic resonance imaging (MRI) revealed lumbar disc herniation at the L5/S1 level. She was diagnosed with LDH. After receiving nonsurgical treatment of traditional Chinese medicine (TCM) for 30 days, the girl had mild low back pain and sciatica and the symptoms had resolved completely at the 3-month follow-up. There was no recurrence within the following 2 years. MRI performed 30 months later revealed that the herniated disc did not shrink significantly. However, she was totally asymptomatic at the follow-up performed 30 months later. Case 2: a 13-year-old boy presented with sciatica in his left leg for over 3 months. The physical examination revealed that Lasegue’s sign was positive in the left leg, the level of muscle strength in the left ankle plantar flexors was grade 4. MRI revealed a lumbar disc herniation at the L5/S1 level. He was diagnosed with LDH. The boy underwent 2 weeks of TCM treatment, and exhibited a favorable outcome: only mild pain was noticed in his left buttocks after walking for more than 15 min. He was asymptomatic at the 3-month follow-up and there was no recurrence within the next 3 years. MRI scan performed at 40 months later showed no significant resorption of the herniated disc. However, he was totally asymptomatic at the follow-up performed 40 months later. Conclusions For the nonsurgical treatment of pediatric LDH, resorption of herniated discs is not necessary for favorable long-term outcomes, and children with symptomatic LDH may become asymptomatic without resorption.
... Based on previous studies, sex, smoking, body mass index (BMI), leisure-time physical activity, occupational physical exposure, education, and Modic changes and disc herniations presenting in lumbar MRI were considered to be potential confounders in the association between LDD and LBP [2,3,[35][36][37][38][39][40][41][42][43][44][45][46][47][48]. These variables were recorded at the 47-year follow-up. ...
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Background: Although it has been suggested that lumbar disc degeneration (LDD) is a significant risk factor for low back pain (LBP), its role remains uncertain. Our objective was to clarify the association between LDD and LBP and whether mental distress modifies the association. Methods: Participants of a birth cohort underwent 1.5-T lumbar magnetic resonance imaging at the age of 47. The association between the sum score of LDD (Pfirrmann classification, range 0-15) and LBP (categorized into "no pain", "mild-to-moderate pain", "bothersome-and-frequent pain") was assessed using logistic regression analysis, with sex, smoking, body mass index, physical activity, occupational exposure, education, and presence of Modic changes and disc herniations as confounders. The modifying role of mental distress (according to the Hopkins Symptom Check List-25 [HSCL-25], the Beck Depression Inventory and the Generalized Anxiety Disorder Scale) in the association was analyzed using linear regression. Results: Of the study population (n = 1505), 15.2% had bothersome and frequent LBP, and 29.0% had no LBP. A higher LDD sum score increased the odds of belonging to the "mild-to-moderate pain" category (adjusted OR corresponding to an increase of one point in the LDD sum score 1.11, 95% CI 1.04-1.18, P = 0.003) and the "bothersome-and-frequent pain" category (adjusted OR 1.20, 95% CI 1.10-1.31, P < 0.001), relative to the "no pain" category. Mental distress significantly modified the association between LDD and LBP, as a linear positive association was consistently observed among individuals without mental distress according to HSCL-25 (adjusted B 0.16, 95% CI 0.07-0.26, P < 0.001), but not among individuals with higher mental distress. Conclusions: LDD was significantly associated with both mild-to-moderate and bothersome-and-frequent LBP. However, the co-occurrence of mental distress diminished the association between LDD and LBP bothersomeness. Our results strongly suggest that mental symptoms affect the pain experience.
... Panel B shows rLDH rates for non-smokers and smokers Table 3 Logistic regression values with rLDH as dependent variable and BMI or smoking, respectively, as well as age and gender as independent variables. Each one-step increase in BMI led to a 1.09-fold increased odds of rLDH, and active smokers had 1. and spondylolysis [35][36][37][38][39]. These effects may be partially explained by the elevated mechanical load on the spine that comes along with obesity, especially with abdominal obesity [40]. ...
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Purpose Recurrent lumbar disk herniation (rLDH) following lumbar microdiscectomy is common. While several risk factors for primary LDH have been described, risk factors for rLDH have only sparsely been investigated. We evaluate the effect of Body mass index (BMI) and smoking on the incidence and timing of rLDH. Methods From a prospective registry, we identified all patients undergoing primary tubular microdiscectomy (tMD), with complete BMI and smoking data, and a minimum 12-month follow-up. We defined rLDH as reherniation at the same level and side requiring surgery. Overweight was defined as BMI > 25, and obesity as BMI > 30. Intergroup comparisons and age- and gender-adjusted multivariable regression were carried out. We conducted a survival analysis to assess the influence of BMI and smoking on time to reoperation. Results Of 3012 patients, 166 (5.5%) underwent re-microdiscectomy for rLDH. Smokers were reoperated more frequently (6.4% vs. 4.0%, p = 0.007). Similarly, rLDH was more frequent in obese (7.5%) and overweight (5.9%) than in normal-weight patients (3.3%, p = 0.017). Overweight smokers had the highest rLDH rate (7.6%). This effect of smoking (Odds ratio: 1.63, 96% CI: 1.12–2.36, p = 0.010) and BMI (Odds ratio: 1.09, 95% CI: 1.02–1.17, p = 0.010) persisted after controlling for age and gender. Survival analysis demonstrated that rLDH did not occur earlier in overweight patients and/or smokers. Conclusions BMI and smoking may directly contribute to a higher risk of rLDH, but do not accelerate rLDH development. Smoking cessation and weight loss in overweight or obese patients ought to be recommended with discectomy to reduce the risk for rLDH.
... Damaged lumbar intervertebral disc and endplates can lead to compression on nerve roots, resulting in traumatic neuropathic pain (9). Shiri et al. found that overweight and obesity were positively correlated with the risk of hospitalization for sciatica and lumbar radicular pain in a meta-analysis of 26 studies (44). Similarly, a recent meta-analysis of 10 cohort studies including 29,748 subjects has indicated that overweight and obesity are risk factors for the development of LBP in both genders (45). ...
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The role of obesity in the development of dorsopathies is still unclear. In this study, we assessed the associations between body mass index (BMI) and several dorsopathies including intervertebral disc degeneration (IVDD), low back pain (LBP), and sciatica by using the Mendelian randomization method. We also assessed the effect of several obesity-related traits on the same outcomes. Single-nucleotide polymorphisms associated with the exposures are extracted from summary-level datasets of previously published genome-wide association studies. Summary-level results of IVDD, LBP, and sciatica were from FinnGen. In our univariable Mendelian randomization analysis, BMI is significantly associated with increased risks of all dorsopathies including sciatica (OR = 1.33, 95% CI, 1.21–1.47, p = 5.19 × 10-9), LBP (OR = 1.28, 95% CI, 1.18–1.39, p = 6.60 × 10-9), and IVDD (OR = 1.23, 95% CI, 1.14–1.32, p = 2.48 × 10-8). Waist circumference, hip circumference, whole-body fat mass, fat-free mass, and fat percentage, but not waist–hip ratio, were causally associated with increased risks of IVDD and sciatica. Higher hip circumference, whole-body fat mass, fat-free mass, and fat percentage increased the risk of LBP. However, only whole-body fat-free mass remained to have a significant association with the risk of IVDD after adjusting for BMI with an odds ratio of 1.57 (95% CI, 1.32–1.86, p = 2.47 × 10-7). Proportions of BMI’s effect on IVDD, sciatica, and LBP mediated by leisure sedentary behavior were 41.4% (95% CI, 21.8%, 64.8%), 33.8% (95% CI, 17.5%, 53.4%), and 49.7% (95% CI, 29.4%, 73.5%), respectively. This study provides evidence that high BMI has causal associations with risks of various dorsopathies. Weight control is a good measure to prevent the development of dorsopathies, especially in the obese population.
... 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). ...
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: 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.
... However, the relationship between CLBPR and cardiovascular health is likely complex. Individuals with CLBPR are more likely to be obese and use tobacco [12][13][14][15]. Obesity and tobacco use are two of the strongest risk factors for cardiovascular disease [16] and, therefore, may largely explain any link between CLBPR and cardiovascular health. ...
Article
Objectives There is considerable overlap in risk profiles between chronic low back pain with radiculopathy (CLBPR) and cardiovascular health among older adults; obesity and smoking are related to both conditions and may largely drive the potential relationship. We sought to explore the impact of CLBPR on cardiovascular health outcomes, independent of body mass index (BMI) and current smoking status. Methods Age- and sex-matched older adults (60–85 years of age) with (n = 21) and without (n = 21) CLBPR were recruited. Current smokers were excluded. Blood samples were collected to measure cholesterol levels and pro-inflammatory markers (i.e., C-reactive protein and interleukin-6). Vascular endothelial function, a marker of cardiovascular health, was evaluated by measuring brachial artery flow-mediated dilation (FMD). General linear models with multifactorial designs were evaluated; group membership, BMI, education, and their respective two-way interaction terms were included as independent variables. Results Older adults with CLBPR had significantly higher BMIs (P = 0.004) and lower educational levels (P = 0.013) than did those without pain. There was a significant group-by-education interaction effect (P = 0.049) for endothelial function. Older adults without pain who were highly educated had higher FMD values, indicating better endothelial function (9.2%), whereas the following combinations all had lower FMD values: no pain plus low education, CLBPR plus high education, and CLBPR plus low education (5.9%, 6.1%, and 6.6%, respectively). Conclusions Among older adults, CLBPR is linked with worse endothelial function, regardless of educational level and independent of BMI and smoking. These findings suggest that older adults with CLBPR may be at a higher risk of cardiovascular disease.
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Aim: This SR aims to assess the effectiveness of pregabalin and gabapentin on pain and disability caused by acute sciatica and the adverse events associated with their clinical use. Design: Systematic review. Databases: Electronic databases of Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Clinical Trials.gov were searched from their inception until March 1st of 2021. Selection criteria: Randomized trials (RCT) with adults > 18 years old with acute sciatica for a minimum of 1 week and a maximum of 1 year (at least moderate pain). Data treatment: The outcomes were pain, disability and adverse events. Data was summarized using odds ratio and mean difference. GRADE was used to calculate the level of evidence. Results: Eight RCT involving 747 participants were included. The effect of pregabalin was assessed in 3 RCT and in one three-arm trial (pregabalin vs limaprost vs a combination of limaprost and pregabalin). Two trials assessed the effect of gabapentin compared with placebo and one compared with tramadol. One study assessed the effect of gabapentin vs pregabalin in a crossover head-to-head trial. A statistically significant improvement on leg pain at 2 weeks and leg pain with movement at 3 and 4 months was found in a RCT comparing gabapentin with placebo. There were no statistically differences on the remaining time periods assessed for leg pain, low back pain and functional disability. Conclusions: This SR provides clear evidence for lack of effectiveness of pregabalin and gabapentin for sciatica pain management. In view of this, its routine clinical use cannot be supported.
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Background: Little is known about disparities in pain treatment associated with weight status despite prior research on weight-based discrepancies in other realms of healthcare and stigma among clinicians. Objective: To investigate the association between weight status and the receipt of prescription analgesics in a nationally representative sample of adults with back pain, adjusting for the burden of pain. Design: Cross-sectional analyses using the Medical Expenditure Panel Survey (2010-2017). Participants: Five thousand seven hundred ninety-one civilian adults age ≥ 18 with back pain. Main measures: We examine the odds of receiving prescription analgesics for back pain by weight status using logistic regression. We study the odds of receiving (1) any pain prescription, (2) three pain prescription categories (opioid only, non-opioid only, the combination of both), and (3) opioids conditional on having a pain prescription. Key results: The odds of receiving pain prescriptions increase monotonically across weight categories, when going from normal weight to obesity II/III, despite adjustments for the burden of pain. Relative to normal weight, higher odds of receiving any pain prescription is associated with obesity I (OR = 1.30 [95% CI = 1.04-1.63]) and obesity II/III (OR = 1.72 [95% CI = 1.36-2.18]). Obesity II/III is also associated with higher odds of receiving opioids only (OR = 1.53 [95% CI = 1.16-2.02]), non-opioids only (OR = 1.77 [95% CI = 1.21-2.60]), and a combination of both (OR = 2.48 [95% CI = 1.44-4.29]). Obesity I is associated with increased receipt of non-opioids only (OR = 1.55 [95% CI = 1.07-2.23]). Conditional on having a pain prescription, the odds of receiving opioids are comparable across weight categories. Conclusions: This study suggests that, relative to those with normal weight, adults with obesity are more likely to receive prescription analgesics for back pain, despite adjustments of the burden of pain. Hence, the possibility of weight-based undertreatment is not supported. These findings are reassuring because individuals with obesity generally experience a higher prevalence of back pain. The possibility of over-treatment associated with obesity, however, may warrant further investigation.
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This study describes the 5 years' results of the Sciatica trial focused on pain, disability, (un)satisfactory recovery and predictors for unsatisfactory recovery. A randomised controlled trial. Nine Dutch hospitals. Five years' follow-up data from 231 of 283 patients (82%) were collected. Early surgery or an intended 6 months of conservative treatment. Scores from Roland disability questionnaire, visual analogue scale (VAS) for leg and back pain and a Likert self-rating scale of global perceived recovery were analysed. There were no significant differences between groups on the 5 years' primary outcome scores. Despite at least 6 months of conservative treatment 46% of the conservatively allocated patients were treated surgically because of severe leg pain and disability. Forty-nine (21%) patients had an unsatisfactory recovery at 5 years and the recovery pattern showed that there was a variable group of 66 patients (31%) with at least one unsatisfactory outcome at 1, 2 or 5 years of follow-up. Multivariate logistic regression showed that age (>40; OR 2.42 (95% CI 1.16 to 5.02)), severity of leg pain (VAS >70; OR 3.32 (95% CI 1.69 to 6.54)) and the Mc Gill affective score (score >3; OR 6.23 (95% CI 2.23 to 17.38)) were the only significant predictors for an unsatisfactory outcome at 5 years. In the long term, 8% of the patients with sciatica never showed any recovery and in at least 23%, sciatica appears to result in ongoing complaints, which fluctuate over time, irrespective of treatment. Prolonged conservative care might give patients a fair chance for pain and disability to resolve without surgery, but with the risk to receive delayed surgery after prolonged suffering of sciatica. Age above 40 years, severe leg pain at baseline and a higher affective Mc Gill pain score were predictors for unsatisfactory recovery. Trial Registry ISRCT No 26872154.
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Anthropometric measurements were studied for their prediction of herniated lumbar intervertebral disc in 332 men and women who had been discharged from hospital with this diagnosis during an 11-year follow-up. The patients were compared with 1,205 controls matched individually for sex, age, and place of residence. Men with a height of 180 cm or more showed a relative risk of 2.3 (95% confidence limits, 1.4-3.9) and women with a height of 170 cm or more 3.7 (1.6-8.6), compared with those who were more than 10 cm shorter (1.0). In men, but not in women, increased body mass index proved to be an independent risk factor for herniated lumbar disc, whereas the thickness of triceps skinfold had no predictive significance. Height and heavy body mass may be important contributors to the herniation of lumbar intervertebral disc.
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IntroductionIndividual studiesThe summary effectHeterogeneity of effect sizesSummary points
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