A principal component model of medical health: implications for cognitive deficits and decline among adults in a population-based sample.

Longitudinal blood- and cognitive data from 879 adults were analyzed to extract a multidimensional health structure for prediction of cognitive change. Six health components were identified and replicated at two waves. Following, cognitive outcomes were regressed on the health components. Large proportions of cognitive age related variations were accounted for by baseline health in both cross-sectional and prospective analyses. Less variation was accounted for when health change and cognitive change were contrasted. Cardiovascular health was particularly important for prediction of cognitive change. Our study underlines causal relations between health and cognitive functions, and suggests that some effects are long term.