Objectives: to measure the effects of childhood mental ability on health in old age.
Design: longitudinal cohort study.
Setting: community-based.
Participants: survivors of the 1932 Scottish Mental Survey cohort randomly selected from the Community Health Index in North East Scotland.
Measurements: (i) presence of disease by diagnostic category; (ii) cardiovascular, respiratory, anthropomorphic, sensory and locomotor physiological variables; (iii) Barthel index of functional independence; (iv) socio-demographic and socio-economic variables as health status predictors; and (v) score on the Moray House Test in 1932.
Results: There was no significant difference in Moray House Test score in 1932 between those with (mean 39.7, S.D. 13.8) and without (mean 40.1, S.D. 12.1) current disease (F = 0.04, P = 0.84). Physiological health status was predicted by demi-span (F = 6.87, P< 0.001), sex (F = 3.69, P = 0.001), deprivation category (F = 1.45, P = 0.05) and the interaction between sex and deprivation category (F = 2.01, P = 0.002). Moray House Test score in 1932 correlated significantly and positively with Barthel score (r = 0.24, P < 0.001). No additional general linear models added any other significant socio-economic variable once Moray House Test Score in 1932 was entered. Moray House Test score in 1932 remained significant (beta = 0.16, P = 0.024) after Mini Mental State Examination score was entered and found to be significant (beta = 0.21, P = 0.003).
Conclusion: socio-economic and socio-environmental factors are important determinants of some aspects of inequalities in health in old age in this cohort. Pre-morbid mental ability was an important independent predictor of late-life functional independence.