Sleeping problems as a risk factor for subsequent musculoskeletal pain and the role of job strain: results from a one-year follow-up of the Malmö Shoulder Neck Study Cohort.

BACKGROUND: The role of sleeping problems in the causal pathway between job strain and musculoskeletal pain is not clear. PURPOSE: To investigate the impact of sleeping problems and job strain on the one-year risk for neck, shoulder, and lumbar pain. METHOD: A prospective study, using self-administered questionnaires, of a healthy cohort of 4,140 vocationally active persons ages 45-64, residing in the city of Malmo. RESULTS: At follow-up, 11.8% of the men and 14.8% of the women had developed pain. The odds ratios (OR) for pain at follow-up and sleeping problems at baseline were 1.72 (95% CI: 1.13-2.61) in men and 1.91 (1.35-2.70) in women. Regarding exposure to job strain, ORs were 1.39 (0.94-2.05) for men and 1.63 (1.18-2.23) for women. These statistically significant risks remained so when controlled for possible confounding. A modest synergistic effect was noted in women with concurrent sleeping problems and job strain, but not in men. CONCLUSION: One in 15-20 of all new cases of chronic pain in the population could be attributed to sleeping problems. No evidence was found for a causal chain with job strain leading to musculoskeletal pain by the pathway of sleeping problems.

Self-rated health in relation to age and gender: influence on mortality risk in the Malmö Preventive Project.

AIMS: A study was undertaken to examine whether poor self-rated health (SRH) can independently predict all-cause mortality during 22-year follow-up in middle-aged men and women. SUBJECTS AND METHODS: Data are derived from a population-based study in Malmö, Sweden. This included baseline laboratory testing and a self-administered questionnaire. The question on global SRH was answered by 15,590 men (mean age 46.4 years) and 10,089 women (49.4 years). Social background characteristics (occupation, marital status) were based on data from national censuses. Mortality was retrieved from national registers. RESULTS: At screening 4,261 (27.3%) men and 3,085 (30.6%) women reported poor SRH. Among subjects rating their SRH as low, 1,022 (24.0%) men and 228 (7.4%) women died during follow-up. Corresponding figures for subjects rating their SRH as high were 1801 (15.9%) men and 376 (5.4%) women. An analysis of survival in subjects reporting poor SRH revealed an age-adjusted hazard risk ratio (HR, 95%CI) for men HR 1.5 (1.4-1.7), and for women HR 1.4 (1.2-1.6). The corresponding HR after adjusting for possible social confounders was for men HR 1.3 (1.1-1.4), and women HR 1.1 (0.9-1.4). When additional adjustment was made for biological risk factors the association for men was still significant, HR 1.2 (1.1-1.3). CONCLUSION: Poor SRH predicts increased long-term mortality in healthy, middle-aged subjects. For men the association is independent of both social background and selected biological variables. The adjustment for biological variables can be questioned as they might represent mediating mechanisms in a possible causal chain of events.