Objectives: Changes in the work ability of active employees were followed over a period of 11 years.
Methods: Men and women in the same occupation (N = 818) in 1981-1992 assessed their work ability according to an index on current work ability, physical and mental work demands, diagnosed diseases, work impairment from disease, sickness absence, work ability prognosis, and psychological resources. Their mean initial age was 46.9 (range 44-51) years. The means and standard deviations of the work ability index and the prevalence rates of 4 work ability categories were followed with respect to age, gender, and job content.
Results: The mean work ability index declined significantly in 11 years for both genders. Its association with age and work was strong. Age of > or = 51 years and physical work load were critical factors affecting the work ability of both genders. At the mean age of 58 years, at least 25% of the installation, auxiliary, or transport workers had a poor work ability rating, as did the women doing kitchen supervision, auxiliary, and home care work. The annual rate of decline in work ability was highest for women aged 51 years at the onset of the study. Female teachers showed a less dramatic decline in work ability than male teachers.
Conclusions: Work does not seem to prevent a decline in the work ability of men and women as they age. Therefore, measures to promote work ability should be started before the age of 51 years, especially for workers in physically demanding jobs.