Original article

Scand J Work Environ Health 2017;43(5):415-425    pdf full text


Cumulative occupational mechanical exposures during working life and risk of sickness absence and disability pension: prospective cohort study

by Sundstrup E, Hansen ÅM, Mortensen EL, Poulsen OM, Clausen T, Rugulies R, Møller A, Andersen LL

Objectives The aim of this study was to determine the prospective association of cumulative mechanical exposure during working life with health-related labor market outcomes.

Methods This prospective cohort study combines data from 5076 older workers (age 49–63 years) from the Copenhagen Aging and Midlife Biobank with a job exposure matrix and a national register containing information on social transfer payment. By coding individual job histories from the Danish version of ISCO-codes (International Standard Classification of Occupations), we calculated cumulative occupational mechanical exposures from a JEM for ton-years (lifting 1000 kg each day in one year), lifting-years (lifting loads weighing ≥20 kg >10 times each day in one year), kneeling-years (kneeling for one hour each day in one year) and vibration-years (whole-body vibration for one hour each day in one year). Cox-regression analyses estimated the relative risk of register-based long-term sickness absence (LTSA) and disability pension with cumulative occupational mechanical exposures throughout working life. Analyses were censored for competing events and adjusted for multiple confounders.

Results During the follow-up period, 970 persons (19.3%) had ≥1 episode of LTSA and 85 persons (1.7%) were granted a disability pension. Number of ton-, lifting- and kneeling-years showed an exposure–response association with increased risk of LTSA (P<0.0001). In addition, both long term [≥20 years; hazard ratio (HR) 1.76 95% CI 1.39–2.22] and short term (<10 years; HR 1.20 95% CI 1.02–1.41) exposure to kneeling work increased the risk of LTSA. Lifting-years, but not the other mechanical exposures, were associated with risk of disability pension (HR 1.75 95% CI 1.01–3.04).

Conclusions Cumulative occupational mechanical exposures during working life – such as lifting and kneeling work – increased the risk of LTSA. Importantly, being exposed to lifting increased the risk of disability pension.

This article refers to the following texts of the Journal: 1992;18(2):105-112  2012;38(6):516-526  2013;39(6):599-608  2016;42(6):481-489  1993;19(3):208-214