Previous research on the association between socioeconomic position (SEP) and dementia has not sufficiently accounted for the complex relationship between education and occupation. We investigated the independent and joint effects of educational attainment and occupation-based SEP on dementia.
Methods
We used register-based information about educational attainment, occupation-based SEP, and dementia from 1,210,720 individuals. Information about cognitive ability at conscription was available for a subsample of men.
Results
When mutually adjusted, lower educational attainment and occupation-based SEP were associated with higher dementia risk in a dose–response manner. Higher occupation-based SEP partly mitigated the higher dementia risk associated with lower educational attainment. After adjusting for cognitive ability in a subgroup of men, only unskilled work was associated with higher dementia risk.
Discussion
Occupation-based SEP is independently associated with dementia and may mitigate the higher dementia risk associated with short education. Future research should elucidate the mechanisms underlying social inequality in dementia.
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