Correction: The role of cumulative physical work load in symptomatic knee osteoarthritis – a case–control study in Germany (Seidler et al. 2008)

ABSTRACT: In the original paper (Seidler et al. 2008), there is a mistake in the results of the occupational group analysis. This mistake occurred when the core data set was merged with the occupational group data. According to the modified occupational group analysis (see modified Table 1), OR for chemical processers and manufacturers of plastics products are no longer significantly elevated. Having worked more than 10 years as metal worker is associated with knee osteoarthritis (OR=2.2; 95% CI 1.1-4.4). The knee osteoarthritis risk of plasterers, insulators, glaziers, terrazzo workers, construction carpenters, roofers, and upholsters approaches statistical significance in the long-duration category (OR=3.7; 95% CI 0.9-15.2). For woodworkers, the knee osteoarthritis risk is no longer significantly elevated. Having worked more than 10 years as painter or varnisher is associated with knee osteoarthritis (OR=9.6; 95% CI 1.2-77.9). Finally, we find a significantly elevated OR of 3.2 (95% CI 1.1-9.1) among subjects having worked as physically exposed service workers (storemen, nurses, refuse collectors) for more than 10 years. When subjects with non-service work as main occupation ("blue-collar workers") are compared with "white-collar workers", the odds ratio for knee osteoarthritis is still significantly elevated (OR=2.0; 95% CI 1.3-2.9)

The role of cumulative physical work load in symptomatic knee osteoarthritis – a case-control study in Germany

<p>Abstract</p> <p>Objectives</p> <p>To examine the dose-response relationship between cumulative exposure to kneeling and squatting as well as to lifting and carrying of loads and symptomatic knee osteoarthritis (OA) in a population-based case-control study.</p> <p>Methods</p> <p>In five orthopedic clinics and five practices we recruited 295 male patients aged 25 to 70 with radiographically confirmed knee osteoarthritis associated with chronic complaints. A total of 327 male control subjects were recruited. Data were gathered in a structured personal interview. To calculate cumulative exposure, the self-reported duration of kneeling and squatting as well as the duration of lifting and carrying of loads were summed up over the entire working life.</p> <p>Results</p> <p>The results of our study support a dose-response relationship between kneeling/squatting and symptomatic knee osteoarthritis. For a cumulative exposure to kneeling and squatting > 10.800 hours, the risk of having radiographically confirmed knee osteoarthritis as measured by the odds ratio (adjusted for age, region, weight, jogging/athletics, and lifting or carrying of loads) is 2.4 (95% CI 1.1–5.0) compared to unexposed subjects. Lifting and carrying of loads is significantly associated with knee osteoarthritis independent of kneeling or similar activities.</p> <p>Conclusion</p> <p>As the knee osteoarthritis risk is strongly elevated in occupations that involve both kneeling/squatting and heavy lifting/carrying, preventive efforts should particularly focus on these "high-risk occupations".</p

Cumulative occupational lumbar load and lumbar disc disease – results of a German multi-center case-control study (EPILIFT)

Background The to date evidence for a dose-response relationship between physical workload and the development of lumbar disc diseases is limited. We therefore investigated the possible etiologic relevance of cumulative occupational lumbar load to lumbar disc diseases in a multi-center case-control study. Methods In four study regions in Germany (Frankfurt/Main, Freiburg, Halle/Saale, Regensburg), patients seeking medical care for pain associated with clinically and radiologically verified lumbar disc herniation (286 males, 278 females) or symptomatic lumbar disc narrowing (145 males, 206 females) were prospectively recruited. Population control subjects (453 males and 448 females) were drawn from the regional population registers. Cases and control subjects were between 25 and 70 years of age. In a structured personal interview, a complete occupational history was elicited to identify subjects with certain minimum workloads. On the basis of job task-specific supplementary surveys performed by technical experts, the situational lumbar load represented by the compressive force at the lumbosacral disc was determined via biomechanical model calculations for any working situation with object handling and load-intensive postures during the total working life. For this analysis, all manual handling of objects of about 5 kilograms or more and postures with trunk inclination of 20 degrees or more are included in the calculation of cumulative lumbar load. Confounder selection was based on biologic plausibility and on the change-in-estimate criterion. Odds ratios (OR) and 95% confidence intervals (CI) were calculated separately for men and women using unconditional logistic regression analysis, adjusted for age, region, and unemployment as major life event (in males) or psychosocial strain at work (in females), respectively. To further elucidate the contribution of past physical workload to the development of lumbar disc diseases, we performed lag-time analyses. Results We found a positive dose-response relationship between cumulative occupational lumbar load and lumbar disc herniation as well as lumbar disc narrowing among men and women. Even past lumbar load seems to contribute to the risk of lumbar disc disease. Conclusions According to our study, cumulative physical workload is related to lumbar disc diseases among men and women

Epidemiological Evidence for Work Load as a Risk Factor for Osteoarthritis of the Hip: A Systematic Review

Osteoarthritis of the hip (OA) is a common degenerative disorder of the joint cartilage that presents a major public health problem worldwide. While intrinsic risk factors (e.g, body mass and morphology) have been identified, external risk factors are not well understood. In this systematic review, the evidence for workload as a risk factor for hip OA is summarized and used to derive recommendations for prevention and further research.Epidemiological studies on workload or occupation and osteoarthritis of the hip were identified through database and bibliography searches. Using pre-defined quality criteria, 30 studies were selected for critical evaluation; six of these provided quantitative exposure data.Study results were too heterogeneous to develop pooled risk estimates by specific work activities. The weight of evidence favors a graded association between long-term exposure to heavy lifting and risk of hip OA. Long-term exposure to standing at work might also increase the risk of hip OA.It is not possible to estimate a quantitative dose-response relationship between workload and hip OA using existing data, but there is enough evidence available to identify job-related heavy lifting and standing as hazards, and thus to begin developing recommendations for preventing hip OA by limiting the amount and duration of these activities. Future research to identify specific risk factors for work-related hip OA should focus on implementing rigorous study methods with quantitative exposure measures and objective diagnostic criteria

Reply to Seafarers’ Occupational Noise Exposure and Cardiovascular Risk. Comments to Bolm-Audorff, U.; et al. Occupational Noise and Hypertension Risk: A Systematic Review and Meta-Analysis. Int. J. Environ. Res. Public Health 2020, 17, 6281

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Dose–Response Relationship between Physical Workload and Specific Shoulder Diseases—A Systematic Review with Meta-Analysis

Several epidemiological studies have found an association between shoulder-loaded work activities and specific shoulder diseases. No study has derived the dose-response relationship and resulting doubling dose, important for the recognition of occupational diseases. This systematic review is an update of the van der Molen et al. (2017) review. Based on its methodologies, we identified new studies published up to November 2018. The dose-response relationship between physical occupational demands (hands at/above shoulder level, repetitive movements, forceful work, hand-arm vibrations) and specific shoulder diseases (defined as ICD-10 M 75.1-5: rotator cuff syndrome, bicipital tendinitis, calcific tendinitis, impingement, and bursitis) was derived. No evidence for sex-specific differences in the dose-response relationship was found. If there were at least two studies with comparable exposures, a meta-analysis was carried out. The pooled analysis resulted in a 21% risk increase (95% CI 4&ndash;41%) per 1000 h of work with hands above shoulder level. A meta-analysis was not possible for other occupational burdens due to the low number of studies and differing exposure measurements; an estimate of the doubling dose was made based on the cohort study of Dalb&oslash;ge et al. (2014). To conclude, the present systematic review with meta-analysis contributes to knowledge of the level of exposure at which specific shoulder diseases&mdash;particularly rotator cuff lesions&mdash;should be recognized as an occupational disease

Lifestyle factors and lumbar disc disease : results of a German multi-center case-control study (EPILIFT).

INTRODUCTION: In the large-scale case-control study EPILIFT, we investigated the dose-response relationship between lifestyle factors (weight, smoking amount, cumulative duration of different sports activities) and lumbar disc disease. METHODS: In four German study regions (Frankfurt am Main, Freiburg, Halle/Saale, Regensburg), 564 male and female patients with lumbar disc herniation and 351 patients with lumbar disc narrowing (chondrosis) aged 25 to 70 years were prospectively recruited. From the regional population registers, 901 population control subjects were randomly selected. In a structured personal interview, we enquired as to body weight at different ages, body height, cumulative smoking amount and cumulative duration of different sports activities. Confounders were selected according to biological plausibility and to the change-in-estimate criterion. Adjusted, gender-stratified odds ratios with 95% confidence intervals were calculated using unconditional logistic regression analysis. RESULTS: The results of this case-control study reveal a positive association between weight and lumbar disc herniation as well as lumbar disc narrowing among men and women. A medium amount of pack-years was associated with lumbar disc herniation and narrowing in men and women. A non-significantly lowered risk of lumbar disc disease was found in men with high levels of cumulative body building and strength training. CONCLUSIONS: According to our multi-center case-control study, body weight might be related to lumbar disc herniation as well as to lumbar disc narrowing. Further research should clarify the potential protective role of body building or strength training on lumbar disc disease