How timings of being physically active in adulthood relate to later‐life cognition: over 30 years of follow up in the 1946 British Birth Cohort

Abstract

AbstractBackgroundWe aim to assess how the timing of being physically active in adulthood is associated with later‐life cognitive function; and estimate to what extent these effects are explained by pathways including earlier life influences, cardiovascular and mental health.MethodData from participants (n = 1417, 53% female) in the British 1946 birth cohort were included. Physical activity was assessed across adulthood at ages 36, 43, 53, 60 and 69 by interviews and categorised into: 0)Not active; 1)Moderately active (participated in physical activity 1‐4 times per month); 2) Most active (participated 5+ times per month). Responses were additionally binarized and summed to create a cumulative exposure of adulthood physical activity. Cognition at age 69 was assessed by the Addenbrooke’s Cognitive Examination (ACE‐III)). Regression analyses examined associations between physical activity measures and later‐life cognition, adjusting for childhood cognition; childhood socioeconomic position (SEP); education; cardiovascular health (Framingham risk score at age 69); emotional symptoms (general health questionnaire at age 69); and APOE‐e4 status. A structural equation modelling analysis further tested the life course models of sensitive period and accumulation for describing how physical activity was best related to later‐life cognition.ResultCompared to those not active, those who were moderately and most physically active, at every age, had higher ACE‐III scores at age 69 (Figure 1). Being physically active across different periods was associated with better cognitive state, in a dose‐response manner (Figure 1). Adjusting for childhood cognition, childhood SEP and education largely attenuated these effects but results mainly remained significant at the 5% level; adjustment for cardiovascular risk, mental health and APOE‐e4 status did not attenuate associations (Figure 1). An accumulation model of physical activity was the best fit (Table 1).ConclusionWe provide evidence from two complementary analyses that maintaining physical activity across different periods of adulthood is related to better later‐life cognitive state in a dose response manner, even after adjustment for variables that predict physical activity and later‐life cognition, such as childhood cognition, education and SEP. These relationships were independent of cardiovascular and mental health and APOE‐E4 status.