Working life job strain status and cognitive aging in Europe: A 12-year follow-up study.

Background: To examine the association of job strain with cognitive ability and the influence of life-course job strain on later life cognitive decline.

Methods: Data were derived from six waves of the Survey of Health, Aging, and Retirement in Europe. The study sample consists of 13349 participants aged 50 to 98 years at wave 2 and has been followed up for 12-years. Job strain status across working life was assessed using a short demand-control job strain model containing two core dimensions: job demands and job control collected in wave 3. Cognitive abilities concerning episodic memory was assessed by immediate recall and delayed recall tests, executive function was evaluated by verbal fluency test collected in all waves (waves 2-7) except wave 3. Mixed-effects model was used to estimate working life job strain and its cumulative effect on cognitive decline.

Results: Both passive and high strain jobs were associated with lower levels of cognitive ability (episodic memory and verbal fluency) in comparison with active job. Long exposure to active- or low strain-job was associated with higher cognitive ability whereas long exposure to passive job or moderate duration of high strain job was associated with lower cognitive ability. The rate of memory decline was positively related to moderate duration of passive job and negatively related to long-term exposure to low strain job.

Limitations: Information on working conditions was based on self-reported recollections.

Conclusions: Working life variation in job strain status and their duration may explain individual differences in cognitive ability in later life.