We examined job control, job demands, social support at work, and job strain (ratio of demands to control) in relation to risk of any dementia, Alzheimer’s disease (AD), and vascular dementia (VaD).
A cohort study.
The population-based Study of Dementia in Swedish Twins.
A total of 257 dementia cases (167 AD, 46 VaD) and 9,849 non-demented individuals.
Dementia diagnoses were based on telephone screening for cognitive impairment followed by in-person clinical work-up. An established job exposure matrix was matched to main occupation categories to measure work characteristics.
In generalized estimating equations (adjusted for the inclusion of complete twin pairs), lower job control was associated with greater risk of any dementia (odds ratio [OR]=1.17, 95% confidence interval [95%CI] 1.04-1.31) and VaD specifically (OR=1.39, 95% CI 1.07-1.81). Lower social support at work was associated with increased risk of dementia (OR=1.15, 95% CI 1.03-1.28), AD (OR=1.14, 95% CI 1.00-1.31), and VaD (OR=1.28, 95% CI=1.02-1.60). Greater job strain was associated with increased risk of VaD only (OR=1.28, 95% CI 1.02-1.60), especially in combination with low social support (OR=1.35, 95% CI 1.11-1.64). Age, gender, education, and cardiovascular disease were controlled. Results were not explained by work complexity or manual work. No differences in work-related stress scores were observed in the 54 twin pairs discordant for dementia, although only two pairs included a twin with VaD.
Work-related stress including low job control and low social support at work may increase the risk of dementia, particularly VaD. Modification to work environment that includes attention to social context and provision of meaningful roles for the workers may contribute to the efforts to promote cognitive health.