Occupational class, physical workload, and musculoskeletal morbidity in the engineering industry

In 1973, 502 employees in three metal industry plants, stratified by age, sex, and occupational class, were examined for physical workload by interview and observation at the workplace and for musculoskeletal disorders by questionnaire, interview, and clinical examination. Five years later, 88% of the sample were re-examined for their musculoskeletal status. The work of the blue collar groups was heavier as measured by indices of physical work load based on the observation and interview (physical strain, physical load, static phases, and stereotypy). Rheumatic symptoms, clinical findings in the musculoskeletal system, and chronic musculoskeletal diseases were more frequent in both female and male blue collar workers than in the respective white collar groups on the first occasion and the increase in morbidity during follow up was higher in the blue collar groups. At an individual level within the blue collar class, however, associations between indices of physical workload and musculoskeletal morbidity were weak or non-existent. The associations were weakened by selective movement of people with musculoskeletal disorders from heavy jobs to premature retirement or to lighter jobs. Physical strain and physical load were negatively associated with the incidence of long term musculoskeletal disorders in the female blue collar group.     

The contribution of musculoskeletal disorders and physical workload to socioeconomic inequalities in health

OBJECTIVES: The objective of the study was to examine whether the association of physical workload with musculoskeletal disorders might explain occupational social class inequalities in self-rated health. METHODS: Participants of the study were 40-60 years old employees of the City of Helsinki. The data (n = 3740) were derived from several sources, including mail survey designed by the researchers and health check-ups carried out by occupational health care. Prevalence data and logistic regression were used in the analyses. RESULTS: An occupational class gradient was found for musculoskeletal disorders. The gradient in musculoskeletal disorders was largely explained by physical demands at work in both genders. The contribution of physical demands to occupational class gradient in self-rated health was considerable in women, but smaller in men. The contribution of musculoskeletal disorder to the occupational class gradient in self-rated health was weak for both genders. CONCLUSION: Physical workload is likely to considerably contribute to inequalities in health. Mediation of this effect through musculoskeletal disorder to generic health, however, could not be demonstrated. Different mechanisms are likely to cause inequalities in different health outcomes.     

Occupational class and physical activity among Japanese employees

We examined the distribution of physical activity among different occupations in Japan. A questionnaire was sent to full-time employees at nine companies in Japan between 1996 and 1998, with an average response rate of 85.2%. Data from 20,654 respondents (17,637 male and 3017 female) were analyzed. We classified the occupations into eight groups according to the International Standard Classification of Occupations (1988). Daily energy expenditure, weekly physical activity, and monthly leisure-time physical activity (LTPA) were measured using a physical activity questionnaire and some additional questions. In males, LTPA was significantly different among occupations, with clerks having greater physical activity than managers and blue-collar workers (P<0.001). The pattern was similar even after adjusting for education, age, and working hours. In females, the difference among occupations was not clear. The distribution of LTPA among occupations exhibits a "barrel-shape" in Japan. It was higher for intermediate class occupations such as clerks, which was in agreement with a lower coronary heart disease mortality observed in intermediate class occupations among Japanese male employees.     

Occupational morbidity of oil industry workers on the mainland and continental shelf]

Data of occupational morbidity in oil industry workers of Azerbaidjan are compared with the mean data in the country. Oil industry workers of mainland and shelf turned out to have different levels of occupational morbidity, depending also on the age and length of service.     

Differences in physical workload,psychosocial factors and musculoskeletal disorders between two groups of female hospital cleaners with two diverse organizational models

Objectives To clarify if differences in the physical workload, the psychosocial factors and in musculoskeletal disorders can be attributed to work organizational factors. Methods The physical workload (muscular activity of m. trapezius, positions and movements of the head, upper arms and wrists and heart rate) was assessed in 24 female hospital cleaners working in a traditional work organization (TO) and in 22 working in an extended one (i.e. with an enlarged work content and more responsibilities; EO). The psychosocial work environment was assessed as job demand, decision latitude and social support in 135 (TO) and 111 (EO) cleaners, and disorders of the neck and upper extremity by a physical examination. Results The EO group was associated with lower physical workload, in terms of heart rate ratio (23 vs 32; P < 0.001), head and upper arm positions and movements (right upper arm, 50th percentile, 35°/s vs 71°/s; P < 0.001) and wrist movements (20°/s vs 27°/s; P = 0.001), than the TO group. The EO group reported higher decision latitude and lower work demand than the TO one, while we found no difference in social support. The prevalence of complaints and diagnoses in neck/shoulders were lower in the EO group (diagnoses 35% vs 48%; P = 0.04). Moreover, the prevalence of subjects with at least ten physical finding in elbows/hands was lower in the EO group (10 vs 29; P < 0.001). Conclusion Hospital cleaners have a high prevalence of neck and upper limb disorders and a high physical workload. Comparing two groups of cleaners, with differences in the way of organizing the work, lower physical workload, more beneficial psychosocial factors and a better musculoskeletal health was found in the group with an extended organization. Hence, the differences found can be attributed to the organizational factors.     

Cancer morbidity among workers in the telecommunications industry.

A retrospective cohort study of 2918 workers in the telecommunications industry in Sweden recorded the cancer morbidity for the period 1958-79. Cases of cancer were collected from the Swedish Cancer Registry for this period and information on work characteristics was collected for the entire period of employment. The total cancer morbidity was as expected. There was no excess risk of lung cancer but an excess risk of malignant melanoma of the skin was detected (SMR = 2.6, 12 cases). This excess risk was particularly associated with work environments where soldering was practised. Estimates of the SMR became larger with the assumption of a longer induction/latency period.     

The influence of occupational class and physical workload on working life expectancy among older employees

Objective:This study investigates the impact of physical workload factors and occupational class on working life expectancy (WLE) and working years lost (WYL) in a sample of older Finnish workers.Methods:A 70% random sample of Finns in 2004 was linked to a job exposure matrix for physical workload factors and register information on occupational class and labor market status until 2014. Transitions between being at work, time-restricted work disability, unemployment, economic inactivity, disability retirement, retirement and death were estimated. A multistate Cox regression model with transition-specific covariates was used to estimate the WLE and WYL at age 50 up to 63 years for each occupational class and physical workload factor for men and women (N=415 105).Results:At age 50, male and female manual workers had a WLE of 10.13 and 10.14 years, respectively. Among both genders, manual workers had one year shorter WLE at age 50 than upper non-manual employees. This difference was largely attributable to unemployment (men: 0.60, women: 0.66 years) and disability retirement (men: 0.28, women: 0.29 years). Self-employed persons had the highest WLE (11.08 years). Men and women exposed to four or five physical workload factors had about one year lower WLE than non-exposed workers. The difference was primarily attributable to ill-health-related reasons, including disability retirement (men: 0.45 years, women: 0.53 years) and time-restricted work disability (men: 0.23, women: 0.33 years).Conclusions:Manual workers and those exposed to physical workload factors had the lowest WLE. The differences in WYL between exposure groups can primarily be explained by ill-health-based exit routes.     

Occupational physical activity and long-term risk of musculoskeletal symptoms: A national survey of post office pensioners

The objective of this work was to address the relationship between physical activity in the workplace and subsequent musculoskeletal pain syndromes. We performed a survey of 5,042 men and women aged 70–75 years, selected from the retirement population of a large national employer (the post office). Subjects were sent a short postal questionnaire enquiring about all occupations held for at least 1 year, the physical activities performed in those jobs, and about recent rheumatic symptoms. The 1-month period prevalence of rheumatic symptoms ranged from 19.9% for hip pain or stiffness in men to 50% for knee pain or stiffness in women. Symptoms were more common in women than men at all sites and there were significant (P < 0.001) associations between symptoms at different sites. Obesity was significantly (P < 0.001) associated with the risk of pain or stiffness at the knee and hip. Prolonged occupational exposure (20+ years) to heavy lifting was associated with hip pain (RR = 1.5; 95% CI = 1.2–1.8); and prolonged exposure to working with arms elevated was associated with an increased risk of shoulder pain (RR = 1.4; 95% CI = 1.2–1.6). Tall stature (P = 0.003) and heavy lifting (P < 0.001) were both associated with increased risks of low back pain among men. This survey confirms the high prevalence of musculoskeletal symptoms observed in previous population-based studies. Associations between occupational activities and musculoskeletal symptoms were specific for activity type and skeletal site involved. Our results imply that the adverse effects of these occupational activities can be found many years after cessation of exposure. Am. J. Ind. Med. 32:76-83, 1997. © 1997 Wiley-Liss, Inc.     

Pressure pain thresholds and musculoskeletal morbidity in automobile manufacturing workers

Objectives: Reduced pressure pain thresholds (PPTs) have been reported in occupational groups with symptoms of upper extremity musculoskeletal disorders (UEMSDs). The purpose of this study was to determine whether automobile manufacturing workers (n=460) with signs and symptoms of UEMSDs had reduced PPTs (greater sensitivity to pain through pressure applied to the skin) when compared with unaffected members of the cohort, which served as the reference group. The association of PPTs with symptom severity and localization of PE findings was investigated, as was the hypothesis that reduced thresholds would be found on the affected side in those with unilateral physical examination (PE) findings. Methods: PPTs were measured during the workday at 12 upper extremity sites. A PE for signs of UEMSDs and symptom questionnaire was administered. After comparison of potential covariates using t tests, linear regression multivariable models were constructed with the average of 12 sites (avgPPT) as the outcome. Results: Subjects with PE findings and/or symptoms had a statistically significant lower avgPPT than non-cases. AvgPPT was reduced in those with more widespread PE findings and in those with greater symptom severity (test for trend, P≤0.05). No difference between side-specific avgPPT was found in those with unilateral PE findings. Reduced PPTs were associated with female gender, increasing age, and grip strength below the gender-adjusted mean. After adjusting for the above confounders, avgPPT was associated with muscle/tendon PE findings and symptom severity in multivariable models. Conclusions: PPTs were associated with signs and symptoms of UEMSDs, after adjusting for gender, age and grip strength. The utility of this noninvasive testing modality should be assessed on the basis of prospective large cohort studies to determine if low PPTs are predictive of UEMSDs in asymptomatic individuals or of progression and spread of UEMSDs from localized to more diffuse disorders.     

Occupational injury deaths in Alaska's fishing industry, 1980 through 1988.

OBJECTIVES. Studies from other countries have identified fishing as a hazardous industry, but little is known about occupational injury mortality related to fishing in the United States. Alaska was chosen for this study because approximately 45,000 people annually participate in Alaska's fishing industry and fishing is thought to be a major contributor to occupational injury mortality in the state. METHODS. Work-related injury deaths in Alaska's fishing industry were identified by means of death certificates and US Coast Guard mortality data. Fatality rates were calculated by using average annual fishing industry employment estimates. RESULTS. The 5-year average annual fishing-related fatality rate was 414.6 per 100,000 fishermen. The majority of the decedents were Caucasian men who drowned while fishing. CONCLUSIONS. This study emphasizes that fishing is a dangerous industry in Alaska and demonstrates the benefit of using multiple data sources to identify fishing-related deaths in the state.     

Occupational safety measures and morbidity among welders in Vellore,Southern India

Background: Welders in the unorganized occupational sector in the economically developing world are exposed to respiratory, skin, eye, ear, and neurological problems exacerbated by non-usage of personal protective equipment (PPE).

Objective: To study the frequency of health problems and the usage of PPE among welders in unorganized welding units in Vellore, India.

Methods: A cross-sectional survey was conducted among 150 welders to determine the frequency of skin, ear, eye, and respiratory morbidity and the usage of PPE. A group of 150 non-welders were chosen for comparison.

Results: Significant differences in the frequency of skin burns, redness, hyper pigmentation, itching, eye injuries, and sensorineural deafness were observed among the welders and non-welders (P < 0.001). Hypertension was noted in 12.6% of the welders as compared to 0.7% among the non-welders. None of the welders used appropriate PPE. For welders, low educational attainment was associated with an increased risk of eye injury (P < 0.05, OR = 0.29). There was also a significant difference between sensorineural deafness and a welder having less than 10 years of welding work experience (P < 0.001, OR = 18.18) which could probably be accounted for by the healthy worker effect.

Conclusion: Welders in this sample experienced a significant skin, eye, and ear morbidity accentuated by the non-usage of PPE. All worked without formal training and were unaware of the safe working guidelines that exist, but are not implemented for the welders in India.