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Pelvic floor tissue damping during running using an intra-vaginal accelerometry approach

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Abstract

Background While cumulative loading of the pelvic floor during exercise appears to increase the risk of developing pelvic floor disorders, the pathophysiologic role of pelvic floor loading is poorly understood. The aim of this exploratory study was to present a method for evaluating vibrational frequency damping of the female pelvic floor and to investigate the potential utility of this approach in a preliminary evaluation. Methods Female participants were instrumented with an intravaginal accelerometer and a hip-mounted accelerometer, then ran on a treadmill at 7 km/h and 10 km/h both before and after a 30-min self-selected pace. Displacement of the pelvic floor relative to the bony pelvis was calculated using double integration of the accelerometer data. Vibrational damping coefficients were calculated using a wavelet-based approach to determine the effect of continence status, parity, running speed and time on vibrational damping. Findings Seventeen women (n = 10 reported regularly leaking urine while exercising, while n = 7 reported not leaking) completed the running protocol. No differences in vibrational damping were detected between continent and incontinent women when all frequency bands were evaluated together, however significant effects of parity, time, running speed and continence status were found within specific frequency bands. Parous women demonstrated less damping in the 25-40 Hz band compared to nulliparae, damping in the 13-16 Hz band was lower after the 30-min run, and incontinent women demonstrated lower damping in the 4.5–5.5 Hz band than continent women when running at 7 km/h. Interpretation Intra-vaginal vibrational damping may be useful in detecting biomechanical mechanisms associated with pelvic floor disorders experienced by females during exercise.

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Introduction: Soft tissue vibrations can generate discomfort and may necessitate a greater energy demand to preserve an efficient motion in running. Vibration damping is thus of interest from a comfort and performance standpoint. Our purpose was to assess whether changes in midsole material affect the properties of (a) soft tissue vibrations and (b) myoelectric activity. Methods: Two midsole conditions were compared. The control condition corresponded to a full ethylene-vinyl acetate foam midsole. The experimental condition was a bimaterial midsole with a material combination of viscous and viscoelastic materials. Twelve participants ran on an indoor track in both conditions while recording the longitudinal acceleration and the EMG activity of vastus medialis (VM) and gastrocnemius medialis (GM). Wavelet transforms were performed for EMG and acceleration signals to assess the intensity of the muscle activity at low and high frequencies (37-128 and 170-395 Hz, respectively) and to calculate the damping coefficient (D) for soft tissue vibrations. The soft tissue vibrations were also characterized by the peak of acceleration (apeak), the frequency of the power peak (fpeak), and the power of the soft tissue vibrations (PSD[8-55]). Results: The variables apeak and PSD[8-55] decreased for VM and GM in the viscous condition. Before heel strike, low-frequency EMG activity decreased for VM, and high-frequency EMG activity tended to decrease for GM in the viscous condition. The damping D was reduced only for VM, and fpeak was unchanged. Conclusions: A more viscous midsole substantially reduced the amplitude of soft tissue vibrations, but not their frequency. Looking at individual results, it was noted that muscle activity was tuned in response to the acceleration input, and that the damping of soft tissue vibrations was affected by the intensity of muscle activity.
Article
Objectives: High intra-abdominal pressure (IAP) may influence the development of pelvic floor disorders. We and others have used intravaginal pressure transducers to measure IAP in women during exercise and daily activities, but utilizing the transducer for long-term measurements creates compliance issues. Waist-worn accelerometers are prominent in research and may be a reliable alternative for approximating IAP. We hypothesized that there are pair-wise positive correlations between the mean maximal accelerometer vector magnitude and 2 IAP measurements: mean maximal IAP and area under the curve (AUC). Methods: Twenty-five women who regularly participated in exercise performed 13 activities. Intra-abdominal pressure was measured with an intravaginal transducer and acceleration with a waist-worn accelerometer. We determined the mean maximal IAP, AUC for IAP, and mean maximal accelerometer vector magnitude for each activity and participant. The relationship between IAP and acceleration was determined by computing the Pearson correlation coefficient (R) and the 95% confidence interval for mean maximal accelerometer vector magnitude versus mean maximal IAP and mean maximal accelerometer vector magnitude versus AUC for IAP. Results: The R values were 0.7353 for mean maximal accelerometer vector magnitude versus mean maximal IAP (including walking) and 0.5059 for mean maximal accelerometer vector magnitude versus AUC for IAP (excluding walking). Walking at 3 speeds, analyzed separately, presented R values of 0.72208 for mean maximal IAP and 0.21678 for AUC. Conclusion: Waist-worn accelerometers may provide a viable method for approximating mean maximal IAP in a population of women during most activities.
Article
Aims: Impact activity like running is associated with an increase in intra-abdominal pressure which needs to be sufficiently countered by pelvic floor muscle (PFM) activity to secure continence. The aim of this study was to investigate and compare PFM kinematics in continent and incontinent women during running. Methos: Three-dimensional position and orientation was measured with the electromagnetic tracking device trakSTAR™. One sensor was attached to the vaginal probe and a second one was secured to the subjects' skin at the height of the second sacral vertebrae. Cranial-caudal and forward-backward displacement of the vaginal probe was measured during 10 sec running on a treadmill at the speeds 7, 11, and 15 km/h. Displacement data from 100 ms before to 300 ms after heel-strike were analyzed. Results: Nineteen incontinent and twenty-seven continent women were included in this study. Before the foot touched the ground caudal translation and forward rotation of the vaginal probe was detected, whereas after heel-strike a cranial translation and backward rotation was measured. Cranial-caudal translation as well as backward-forward-rotation did not differ significantly between continent and incontinent subjects for the three speeds. Analysis of maximum displacements showed significantly increasing displacement with increasing speeds. Conclusions: Kinematic measurements during impact activity of running demonstrated caudal translation before and cranial translation after heel-strike. The hypothesis of caudal translation through impact activity was not confirmed. Patterns seem similar between continent and incontinent subjects. Associations between the direction of displacement and muscle action of PFMs remain assumptions.
Article
Purpose of review: To summarize recent literature about the potential role of chronic exercise on pelvic floor support and function. Recent findings: Stress urinary incontinence is common during physical activity. Scant evidence suggests a dose-response association between higher volumes of exercise and urinary incontinence. Athletes do not appear to have greater pelvic floor muscle strength or worse pelvic floor support compared to nonathletes. Pelvic floor muscle electromyographic activity increases substantially as running speeds increase. Summary: Based on the current literature, no strong conclusions can be drawn about whether chronic exercise exerts a positive or negative influence on pelvic floor support and function. Adopting longitudinal research methodology that prospectively monitors exercise exposure and subsequent changes in pelvic floor support and function would help to reduce selection bias associated with cross sectional studies on groups of athletes.
Article
Aims: To determine the prevalence and severity of urinary incontinence (UI) in a group of female nurses and midwives, and to examine the relationship between UI, work and intention to leave current job. Methods: An electronic survey "Fit for the future" was distributed to nurses and midwives in NSW, Australia between May 2014 and February 2015. UI was investigated using the International Consultation on Incontinence UI-Short Form. Examined work characteristics included: work role, location, setting, contract, shift, job satisfaction, and plans to leave current job. Logistic regression modelling was performed to determine whether the severity of UI had an independent effect on intention to leave. Results: Of 5041 survey responses, 68.5% answered the question on urine leakage. Of the included female sample (n = 2,907) the prevalence of UI was 32.0% (95% CI: 30-34%): of these 40.5% experienced moderate and 4.4% "severe or very severe" symptoms. UI was more likely to be reported in nurses or midwives working part-time or days only (not shifts). Those with "severe or very severe UI" were more likely to indicate an intention to leave at 12 months (OR: 2.68; 95% CI: 1.18-6.06) than those with slight or moderate symptoms, after accounting for age, body mass index, parity, pelvic organ prolapse, anxiety, depression, work contract, shift, and job satisfaction. Conclusions: UI is a condition of high prevalence and significant severity in female nurses and midwives. In this workforce, severe UI was associated with intentions related to future employment.
Article
Muscle tuning paradigm proposes that the mechanical properties of soft tissues are tuned in such a way that its vibration amplitude become minimized. Therefore, the vibrations of soft tissue are heavily damped. However, it has been hypothesized that the ability of muscle tuning decreases with fatigue. This study investigated the changes in vibration characteristics of soft tissue with fatigue. Vibrations of the gastrocnemius muscle of 8 runners during a prolonged run protocol on a treadmill at constant velocity (4 ms−1) were measured using a tri-axial accelerometer. The vibration amplitude is calculated using the Fourier transform and a wavelet-based method was used to calculate the damping coefficient. The results showed that: (1) the vibration amplitude in longitudinal direction increased with fatigue, which may be interpreted as the decreased muscle function with fatigue. (2) The amplitude increase percent strongly depended on the vibration frequency. (3) The damping coefficient of the gastrocnemius increased with fatigue. A 1-DOF mass-spring-damper model was used in order to validate the wavelet based method and simulate the observed phenomena.
Article
Pelvic floor disorders (PFDs) are common, with one in four U.S. women reporting moderate to severe symptoms of urinary incontinence, pelvic organ prolapse or fecal incontinence. Given the high societal burden of these disorders, identifying potentially modifiable risk factors is crucial. Physical activity is one such potentially modifiable risk factor; the large number of girls and women participating in sport and strenuous training regimens increases the need to understand associated risks and benefits of these exposures. The aim of this review is to summarize studies reporting the association between physical activity and PFDs. Most studies are cross-sectional and most include small numbers of participants. The primary findings of this review include: Urinary incontinence during exercise is common and is more prevalent in women during high-impact sports. Mild to moderate physical activity, such as brisk walking, decreases both the odds of having and the risk of developing urinary incontinence. In older women, mild to moderate activity also decreases the odds of having fecal incontinence; however, young women participating in high intensity activity are more likely to report anal incontinence than less active women. Scant data suggest that in middle-aged women, lifetime physical activity increases the odds of stress urinary incontinence slightly and does not increase the odds of pelvic organ prolapse. Women undergoing surgery for pelvic organ prolapse are more likely to report a history of heavy work than controls; however, women recruited from the community with pelvic organ prolapse on examination report similar lifetime levels of strenuous activity as women without this exam finding. Data are insufficient to determine whether strenuous activity while young predisposes to pelvic floor disorders later in life. The existing literature suggests that most physical activity does not harm the pelvic floor and does provide numerous health benefits for women. However, future research is needed to fill the many gaps in our knowledge. Prospective studies are needed in all populations, including potentially vulnerable women, such as those with high genetic risk, levator ani muscle injury, or asymptomatic pelvic organ prolapse, and on women during potentially vulnerable life periods, such as the early postpartum or post-operative periods.
Article
To estimate whether moderate/severe stress urinary incontinence (SUI) in middle-aged women is associated with overall lifetime physical activity (including leisure, household, outdoor, and occupational), as well as lifetime leisure (recreational), lifetime strenuous and strenuous activity during the teen years. Recruitment for this case-control study was conducted in primary care level family medicine and gynecology clinics. 1538 enrolled women ages 39-65 years underwent a Pelvic Organ Prolapse Quantification examination to assess vaginal support. Based on Incontinence Severity Index scores, cases had moderate/severe and controls no/mild SUI. We excluded 349 with vaginal descent at/ below the hymen (pelvic organ prolapse), 194 who did not return questionnaires, and 110 with insufficient activity data for analysis. 213 cases were frequency-matched 1:1 by age group to controls. Physical activity was measured using the Lifetime Physical Activity Questionnaire, in which women recall activity from menarche to present. We created separate multivariable logistic regression models for activity measures.Results: SUI odds increased slightly with overall lifetime activity (OR 1.20 per 70 additional MET-hrs/wk; 95% CI 1.02, 1.41), and were not associated with lifetime strenuous activity (OR 1.11; 95% CI 0.99, 1.25). In quintile analysis of lifetime leisure activity, which demonstrated a non-linear pattern, all quintiles incurred about half the odds of SUI compared to reference (2(nd) quintile; p=0.009). Greater strenuous activity in teen years modestly increased SUI odds (OR 1.37 per 7 additional hours/week; 95% CI 1.09, 1.71); OR 1.75; 95% CI 1.15, 2.66 in sensitivity analysis adjusting for measurement error. The predicted probability of SUI rose linearly in women exceeding 7.5 hours of strenuous activity/week during teen years. Teen strenuous activity had a similar effect on SUI odds when adjusted for subsequent strenuous activity during ages 21-65 years. In middle-aged women, a slight increased odds of SUI was noted only after substantially increased overall lifetime physical activity. Increased lifetime leisure activity decreased and lifetime strenuous activity appeared unrelated to SUI odds. Greater strenuous activity during teen years modestly increased SUI odds. Copyright © 2015 Elsevier Inc. All rights reserved.
Article
To survey commercially available intravaginal probes designed to record electromyography (EMG) from the pelvic floor muscles (PFMs), and to discuss the strengths and limitations of current technology. The MEDLINE EMBASE, CINAHL, PEDRO, and Cochrane databases were searched for articles in which intravaginal probes were described as having been used to record EMG from the PFMs. The World Wide Web was also searched using the Google search engine to find devices used to record EMG from the PFMs. Finally, a Canadian distributer of intravaginal probes was contacted to identify intravaginal EMG probes not identified through other methods. The specifications of each probe were determined through the manufacturer or their website, and each device was acquired by the investigators to verify the specifications and electrode configuration. The devices were evaluated against international standards for recording EMG data. Sixteen different models of commercially available intravaginal probes were identified: seven from published research papers, seven using the World Wide Web, and two through communication with a distributer. The probes vary in shape, dimensions, electrode positioning, and electrode configuration, with many designs prone to recording motion artifact, crosstalk, and/or inappropriate EMG signals. All commercially available intravaginal probes had deficiencies in their design such as problems with probe geometry, electrode size, location, and/or configuration. Improved intravaginal EMG probes should be developed for use in research and clinical practice. Neurourol. Urodynam. © 2013 Wiley Periodicals, Inc.
Article
Objectives: To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot. Design: Cross-sectional study. Methods: Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue. Results: The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (p<0.001). A lower damping coefficient indicates less damping of the vibrations. The barefoot forefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (p<0.001). The shod rearfoot strike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients. Conclusions: This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations.
Article
The purpose of this study was to determine whether a differential suction electrode (DSE) probe is less prone to recording crosstalk from the hip adductors or external rotators than the Femiscan™ probe when recording electromyography (EMG) data from the pelvic floor muscles (PFMs). Twenty nulliparous, continent women performed hip adduction and hip external rotation contractions at 25%, 50% and 100% of maximal voluntary effort both while keeping their PFMs relaxed and while contracting their PFMs as strongly as possible. All tasks were performed while DSEs were adhered to the vaginal wall at the level of the pubococcygeus group bilaterally, and also with the Femiscan™ probe in situ. The order of the probes was randomized. For each task, the peak smoothed PFM EMG amplitude was compared between hip forces and probes using a two-way repeated measures analysis of variance (ANOVA) including the interaction between contraction level and probe (α=0.05). There was a significant contraction level by probe interaction for each task. In most cases the Femiscan™ probe recorded significantly higher PFM EMG activity during hip adduction and external rotation tasks at 25% and 50% MVC compared to what it recorded when the hip musculature remained relaxed, whereas the DSE probe did not. As such, the DSE probe appears to be less susceptible to crosstalk from the hip adductors and external rotators than the Femiscan™ probe at these hip muscle contraction levels. Both probes recorded significantly higher EMG activity when maximal contractions of the hip adductors and external rotators were performed therefore, no conclusion can be made regarding whether the activity recorded from the PFMs during maximal hip adduction and external rotation is the result of crosstalk or co-activation.
Article
Urinary incontinence (UI) is a distressing condition that affects the lifestyle of older people. To investigate the relationship between UI and physical activity among older adults, a community-based study was conducted in Japan. A total of 700 men and 300 women (mean age 66.2, SD 7.7 years) were recruited from the community in middle and southern Japan. The International Consultation on Incontinence Questionnaire-Short Form was administered by face-to-face interviews to ascertain UI status. Habitual physical activity levels (walking, moderate and vigorous activities) were assessed using the International Physical Activity Questionnaire and measured in terms of energy expenditure as metabolic equivalent tasks (MET). The prevalence of UI was 7.2% (n = 49) among the 683 eligible male participants and 27.5% (n = 82) among the 298 female participants, who had experienced urine leakage for 2.6 (SD 1.9) years and 4.2 (SD 5.1) years, respectively. Habitual walking levels were lower among incontinent subjects than others without the condition. The adjusted risk of UI was 0.36 (95% confidence interval (CI) 0.14, 0.92) for men and 0.43 (95% CI 0.20, 0.96) for women, when comparing frequent walkers with over 1000 MET minutes of walking per week to completely sedentary participants. The prevalence of UI also decreased with total and moderate activity levels, but the corresponding reductions in risk were not statistically significant. The finding of an inverse association between UI and walking has important implications for the prevention and treatment of this distressing condition.
Article
Procedures for the preliminary screening of asymptomatic adults who wish to exercise are reviewed with particular reference to experience gained through the mass use of the physical activity readiness questionnaire (PAR-Q) and the Canadian Home Fitness Test (CHFT). It is argued that both a brief submaximal exercise test and a subsequent moderate increase of habitual activity are extremely safe tactics to recommend to a symptom-free adult. There are some useful minor modifications which could be made to the PAR-Q instrument, but its sensitivity and specificity relative to such criteria as medical examination, hypertension, CHFT completion and exercise-induced ECG abnormalities compare favourably with alternative self-administered procedures. The basic difficulty of screening an asymptomatic population (highlighted by Bayes theorem) is the high percentage of false positive and false negative test results. One remedy would be to stratify the population in terms of known cardiac risk factors and to restrict detailed pre-exercise screening to the high risk segment of the population.
Article
This study examines the anatomic factors that could explain the mechanical basis for transmission of abdominal pressure to the urethra. Dissection of 19 embalmed and 42 fresh cadavers and examination of 13 sets of serial pelvic sections were performed to study the structures involved in urethral support. The effect of simulated increases in abdominal pressure on the pelvic floor and urethra was observed in fresh specimens. The urethra lies on a supportive layer that is composed of the endopelvic fascia and the anterior vaginal wall. This layer gains structural stability through its lateral attachment to the arcus tendineus fascia pelvis and levator ani muscle. Pressure from above compresses the urethra against this hammock-like supportive layer, compressing its lumen closed. The stability of the suburethral layer depends on the intact connection of the vaginal wall and endopelvic fascia to the arcus tendineus fasciae pelvis and levator ani muscles. Increases in urethral closure pressure during a cough probably arise because the urethra is compressed against a hammock-like supportive layer, rather than the urethra being truly "intraabdominal."
Article
To determine the correlates of incontinence in middle-aged women and to test for an association between incontinence and depression. This was a population-based cross-sectional study of 5701 women who were residents of the United States, aged 50-69 years, and participated in the third interview of the Health and Retirement Study. The primary outcome measure was self-reported urinary incontinence. Depression was ascertained based on criteria set by the Diagnostic and Statistical Manual of Mental Disorders, using a short form of the Composite International Diagnostic Interview. In addition, depressive symptoms were assessed using the revised Center for Epidemiologic Studies Depression Scale. Multivariable logistic regression models were constructed to determine the independent association between incontinence and depression, after adjusting for confounders. Approximately 16% reported either mild-moderate or severe incontinence. Depression, race, age, body mass index, medical comorbidities, and limited activities of daily living were associated with incontinence. After adjusting for medical morbidity, functional status, and demographic variables, women with severe and mild-moderate incontinence were 80% (odds ratio [OR] 1.82; 95% confidence interval [CI] 1.26, 2.63) and 40% (OR 1.41; 95% CI 1.06, 1.87) more likely, respectively, to have depression than continent women. The association did not hold for depressive symptoms measured by the revised Center for Epidemiologic Studies Depression Scale after adjusting for covariates. Depression and incontinence are associated in middle-aged women. The strength of the association depends on the instrument used to classify depression. This reinforces the need to screen patients presenting for treatment of urinary incontinence for depression.
Article
The objective of the study was to determine the proportions of women with urinary incontinence who had discussed their condition with a health care provider or received treatment and to identify factors associated with seeking health care. The study was a population-based, age-stratified postal survey of 6000 women aged 30 to 90 years enrolled in a large health maintenance organization in Washington state. The response rate was 64% (n = 3536) after applying exclusion criteria. Eighty percent (n = 1160) of women with urinary incontinence completed a detailed set of questions on care seeking and treatments. Fifty percent had discussed their incontinence with a health care provider, 21% reported receiving surgery or prescription medication, 10% reported performing Kegel exercises, and 48% reported wearing a pad to absorb urine daily or weekly. The following factors were significantly associated with odds of discussing urinary incontinence with a health care provider: age (50 to 69 years, adjusted odds ratio 1.5 [1.1 to 2.0]; 70 to 89 years, adjusted odds ratio 1.9 [1.4, 2.7]); duration of urinary incontinence (2 to 5 years, adjusted odds ratio 1.9 [1.3 to 2.8]; more than 5 years, adjusted odds ratio 2.8 [2.0,4.1]); severe urinary incontinence (adjusted odds ratio 1.7 [1.2 to 2.6]); and greater effect on daily activities (adjusted odds ratio 2.7 [1.9,3.8]). Among women with urinary incontinence, one half have discussed their incontinence with a health care provider and one third have received any form of treatment.
Article
The development of novel, less invasive therapies for stress urinary incontinence in women requires a thorough knowledge of the relationship between the pathophysiology of incontinence and anatomy. This article provides a review of the anatomy of the pelvic floor and lower urinary tract. Also discussed is the hammock hypothesis, which describes urethral support within the pelvis and provides an explanation of the continence mechanism.
Article
Previous studies of lower urinary tract symptoms (LUTS) have focused on men, with few studies including minority populations. The Boston Area Community Health (BACH) Survey is designed to study the prevalence and impact of LUTS among both men and women in a racially, ethnically, and socioeconomically diverse population. The BACH Survey used a stratified 2-stage cluster design to randomly sample 5506 adults aged 30 to 79 from the city of Boston, Mass (2301 men, 3205 women, 1770 blacks, 1877 Hispanics, and 1859 whites). Data were obtained using interviewer and self-administered questionnaires. The presence of LUTS was defined as an American Urological Association symptom index score of 8 or above. Quality of life was assessed using the Medical Outcomes Study 12-Item Short Form Survey (SF-12), and a measure of bother was based on the interference of urinary symptoms with various activities. Analyses were weighted to the Boston population using SUDAAN version 9.0 statistical software. The overall prevalence of LUTS was 18.7% and increased with age (10.5% at age 30-39 years to 25.5% at age 70-79 years) but did not differ by sex or race/ethnicity. Quality of life was significantly reduced among those with LUTS, as measured by the bother of symptoms and the SF-12 component scores. Prevalence of prescription medication use for urinary symptoms was low even among participants with LUTS, with more than 90% of participants reporting no medication use. In this population-based, racially and ethnically diverse random sample, LUTS were common among both men and women and increased substantially with age. Lower urinary tract symptoms had a negative impact on quality of life across age, sex, and race/ethnic groups.
Article
To estimate the US prevalence and psychological and health behavior correlates of low back pain and/or neck pain. No current US national prevalence estimates of low back and neck pain exist and few studies have investigated the associations between low back and neck pain, psychological factors, and health behaviors in a representative sample of US community dwellers. We analyzed data obtained from adults ages 18 years or older (n = 29,828) who participated in the 2002 National Health Interview Survey, a cross-sectional, population-based survey of US adults. The 3-month US prevalence of back and/or neck pain was 31% (low back pain: 34 million, neck pain: 9 million, both back and neck pain: 19 million). Generally, adults with low back and/or neck pain reported more comorbid conditions, exhibited more psychological distress (including serious mental illness), and engaged in more risky health behaviors than adults without either condition. Low back and neck pain are critical public health problems. Our study supports the idea of a multidimensional approach to examining low back and neck problems and suggests the need for further research to address potentially modifiable psychological factors and health behaviors in these populations.
Article
While strenuous, high impact activity may provoke urinary incontinence, little is known about relations with moderate physical activity. We examined recreational activity and incident urinary incontinence in middle-aged women. This is a prospective study of women 37 to 54 years old in the Nurses' Health Study II. Repeated physical activity reports from 1989 to 2001 were averaged to estimate long-term activity levels. From 2001 to 2003 we identified 4,081 incident cases with at least monthly urinary incontinence. Incontinence type was further determined among cases with at least weekly urinary incontinence. Multivariable logistic regression models were used to estimate adjusted relative risks of urinary incontinence across quantiles of physical activity. To determine whether relations were mediated by body mass index, separate models were constructed that excluded and included body mass index as a covariate. The risk of at least monthly urinary incontinence decreased with increasing quintiles of moderate physical activity (RR 0.80, 95% CI 0.72-0.89 comparing extreme quintiles). For stress and urge urinary incontinence, women with the most physical activity had lower rates of incontinence than those with less activity. RRs were 0.75 (95% CI 0.59-0.96 for top vs bottom quartile) for stress urinary incontinence and 0.53 (95% CI 0.31-0.90) for urge urinary incontinence. After adjustment for body mass index, the overall association with at least monthly incontinence attenuated, but remained significant (RR 0.89, 95% CI 0.80-0.99 comparing extreme quintiles). Long-term, moderate physical activity was inversely associated with urinary incontinence. The role of exercise in weight maintenance may partly explain this association.
Article
There is growing interest in causal factors for pelvic floor disorders. These conditions include pelvic organ prolapse and urinary and fecal incontinence and are affected by a myriad of factors that increase occurrence of symptomatic disease. Unraveling the complex causal network of genetic factors, birth-induced injury, connective tissue aging, lifestyle and comorbid factors is challenging. We describe a graphical tool to integrate the factors affecting pelvic floor disorders. It plots pelvic floor function in 3 major life phases: (1) development of functional reserve during an individual's growth, (2) variations in the amount of injury and potential recovery that occur during and after vaginal birth, and (3) deterioration that occurs with advancing age. This graphical tool accounts for changes in different phases to be integrated to form a disease model to help assess the overlap of different causal factors.
Epidemiology of surgically managed pelvic organ prolapse and urinary incontinence
  • Olsen
Olsen, A.L., Smith, V.J., Bergstrom, J.O., Colling, J.C., Clark, A.L., 1997. Epidemiology of surgically managed pelvic organ prolapse and urinary incontinence. Obstet. Gynecol. 89 (4), 501-506. Apr. https://doi.org/10.1016/S0029-7844(97)00058-6.
Prevalence of lower urinary tract symptoms and effect on quality of life in a racially and ethnically diverse random sample: the Boston Area Community Health (BACH) survey
  • Kupelian
Kupelian, V., et al., 2006. Prevalence of lower urinary tract symptoms and effect on quality of life in a racially and ethnically diverse random sample: the Boston Area Community Health (BACH) survey. Arch. Intern. Med. 166 (21), 2381-2387. Nov. https://doi.org/10.1001/archinte.166.21.2381.
Epidemiology of surgically managed pelvic organ prolapse and urinary incontinence.
  • Olsen A.L.
  • Smith V.J.
  • Bergstrom J.O.
  • Colling J.C.
  • Clark A.L.