An exploratory analysis of the associations between accelerometer-derived measures and future health-related changes in older adults: preliminary results on prospective cohort study

Accelerometer-derived cognitive, mental, and physical health measures are predictors of multiple health-related changes. However, previous studies analyzed only a few health-related domains, whereas comprehensive associations with physical, cognitive, and mental health have not been fully studied. Here we collected accelerometer-derived measures for physical activity and sleep in free-living settings along with self-reported qualitative data on daily physical activities and investigated their associations with health-related changes and events (car accidents and dementia severity) in physical, cognitive, and mental health after 1 year of follow-up. Accelerometer-derived measures were associated with multiple health-related changes (P<0.05): (i) lower moderate/vigorous physical activity with worsening cognitive scores; (ii) lower vigorous physical activity with car accidents; (iii) lower moderate/vigorous physical activity with worsening dementia severity; and (iv) lower sleep efficiency with worsening cognitive scores. In contrast, lower metabolic equivalents (METs) calculated from qualitative data of daily physical activities were uniquely associated with worsening mental health and cognitive scores (P<0.05), although there was no association with accelerometer-derived mental health measures. Our findings suggest that accelerometer-derived measures could be useful for predicting future cognitive decline and the risk of car accidents. Moreover, enabling the quantification of METs from accelerometer data would be helpful for predicting changes in mental health.