Objective: The aim of the study was to test the hypothesis that higher childhood cognitive ability is associated with reduced risk of decline in physical capability in late midlife.
Methods: Participants were 1954 men and women from the Medical Research Council National Survey of Health and Development with complete data on cognitive ability at age of 15 years and measures of grip strength and chair rise speed at ages of 53 and 60 to 64 years. Using multinomial logistic regression, associations of childhood cognitive ability with categories of change in grip strength and chair rise speed (i.e., decline, stable high, stable low, reference) were investigated. Adjustments were made for potential confounders from early life and adult mediators including health behaviors, educational level, and cognitive ability at age of 53 years.
Results: Higher childhood cognitive scores were associated with reduced risks of decline in grip strength and chair rise speed, for example, the sex-adjusted relative-risk ratio of decline (versus reference) in grip strength per 1SD increase in childhood cognitive score was 0.82 (95% confidence interval = 0.73-0.92). Higher childhood cognitive scores were also associated with reduced risk of stable low and increased likelihood of stable high chair rise speed.
Conclusions: These findings suggest that childhood cognitive ability may be related to decline in physical capability in late midlife. A number of life course pathways are implicated, including those linking childhood and adult cognitive ability. Future research aiming to identify new opportunities to prevent or minimize age-related declines in physical capability may benefit from considering the potential role of neurodevelopmental as well as neurodegenerative pathways.