Research Plus: February/March 2009

Participatory ergonomics

A two-year randomised controlled trial in Finland studied the impact of participatory ergonomics on the development of musculoskeletal disorders. The study involved 504 workers in 119 municipal kitchens (randomised into 60 control and 59 intervention groups). Workers in the intervention kitchens were taught basic principles of ergonomics and the functioning of the musculoskeletal system, then trained in task and risk analysis and on seeking solutions to decrease their physical and mental workload.

Workers were followed every three months during the nine-to-12 month intervention and one year after. Although participation was good, the intervention neither reduced perceived physical workload, nor the prevalence of musculoskeletal pain, nor related sick leave.

Occupational and Environmental Medicine 2008; 65(12): 849–856.

Arthritis and return to work

A prospective cohort study carried out in the Netherlands on workers with early inflammatory joint conditions – such as rheumatoid arthritis – found that high levels of pain, poor physical functioning and frequent manual handling were significant predictors of sick leave. Poor physical functioning, intermediate pain, poor mental health, and low support from colleagues predicted reduced work productivity. Supervisors were less likely than other workers to take sick leave. A total of 210 patients, aged 18–65 and in paid employment, were included in the study, with data on 186 available after 12 months. Medical interventions should target pain and physical functioning as well as disease activity, while workplace interventions should aim to reduce physical workload and improve social support.

Scandinavian Journal of Work, Environment and Health 2008; 34(6): 420–429.

Health promotion, absence and wellbeing

A systematic review and meta-analysis finds that while workplace health promotion may provide some benefit in terms of job wellbeing, work ability and sickness absence, education and psychological interventions applied alone are ineffective. Forty-six studies from an initial trawl of 1,312 abstracts published between 1970 and 2005 were included in the analysis, though the quality of the results was considered ‘good’ in only three of them; ‘moderate’ in 21 and ‘poor’ in 22. There was only weak evidence that health promotion improves job wellbeing, mental wellbeing and work ability, and moderate evidence that it can decrease sickness absence. Reported relative risks were rarely significant. There is some evidence that exercise improves overall wellbeing, mental wellbeing, work ability and decreases sickness absence.

Journal of Occupational and Environmental Medicine 2008; 50(11): 1216–1227.

Radiation workers

Analysis of over 52,600 cases and matched controls concludes that there is no evidence of an increased risk of childhood cancer (overall or by diagnostic group) associated with maternal preconception radiation work. An earlier study, published in 1997 by the same research group, had found an association but this was not supported by analysis of an expanded data pool, which included 16,964 new cases. Childhood cancer cases (diagnosed before 15th birthday) were identified from the National Registry of Childhood Tumours and linked to data from the National Registry for Radiation Workers. The analysis covered British-born children diagnosed between 1952 and 1999.

British Journal of Cancer (2009) 100, 213–218.

Exercise prescription

A primary care based study in New Zealand finds that ‘exercise prescriptions’ can produce sustained increases in physical activity among less active middle-aged and older women. The randomised controlled trial followed 1,089 women aged 40–74, all of whom did relatively little exercise. The intervention group were given a ‘green prescription’ by a nurse, which detailed the exercise advice, followed by telephone support. Both groups increased their physical activity, but the numbers achieving the weekly target of 150 minutes of at least moderate intensity physical activity was significantly higher in the intervention group, after 12 and 24 months. However, while physical functioning and mental health scores improved, there were no significant differences in clinical outcomes (eg weight, blood pressure, waist circumference and fasting serum lipids).

British Medical Journal 2008; 337: a2509 (doi:10.1136/ bmj.a2509).

Work-related upper limb disorders

Over-attribution of upper limb disorders (ULDs) to work can be detrimental to recovery, a review of evidence finds. Over-medicalisation and negative diagnostic labels are also unhelpful. The review of literature published from 1996 presents ‘evidence statements’ covering classification and diagnosis, epidemiology, associations and risks, interventions and return to work. Self-management should be encouraged, with interventions based on biopsychosocial principles. Early return to work is important, with transitional arrangements and temporary work modifications where appropriate.

Occupational Medicine 2009; 59: 44–52.

Pesticide production workers

A systematic review and meta-analysis (21 papers met inclusion criteria) finds that workers involved in pesticide manufacturing have lower all-cause mortality than the general population, and a significant reduction in cardiovascular disease. Nevertheless, the review found a ‘lack of a healthy worker effect’ for some non-malignant diseases with significant (though small) raised standardised mortality ratios for some cancers, including cancers of the buccal cavity, pharynx, oesophagus, larynx and lung. Similar results were seen for the subgroup of workers exposed to phenoxy herbicides.

Occupational and Environmental Medicine 2009; 66(1); 7–15.

Fibromyalgia treatment meta-analysis

Fibromyalgia is a chronic pain disorder associated with multiple debilitating symptoms and, it has been suggested, may share a common pathophysiology with chronic fatigue syndrome. A meta-analysis on the treatment of fibromyalgia syndrome with anti-depressants identified 18 randomised controlled trials, covering 1,427 participants; three studies included information on working status. There is strong evidence for an association of antidepressants with a reduction in pain, fatigue, depressed mood, sleep disturbances and with improved health-related quality of life.

Journal of the American Medical Association 2009; 301(2): 198–209.

Injury perceptions and return to work

There is no conclusive evidence from published research on whether or not individuals’ perceptions about their injuries affect their return to work (RTW); though pain catastrophising may influence RTW outcome and is a promising area for research. A systematic review of literature to March 2007 found 30 studies and six review articles, with 17 excluded owing to design flaws. There was too little evidence to conclude that expectations of recovery have a significant effect on RTW outcome. Pain catastrophising score, but not perceived disability, explains some of the outcome variance in studies.

Journal of Occupational Rehabilitation 2008; 18(4): 362–374.