Exploring Shared Effects of Multisensory Impairment, Physical Dysfunction, and Cognitive Impairment on Physical Activity: An Observational Study in a National Sample.

Multisensory, physical, and cognitive dysfunction share age-related physiologic disturbances and may have common health effects. We determined whether the effect of multisensory impairment on physical activity (PA) is explained by physical (timed up and go) or cognitive (Short Portable Mental Status Questionnaire) dysfunction. A National Social Life, Health, and Aging Project participant subset (n = 507) underwent objective sensory testing in 2005-2006 and wrist accelerometry in 2010-2011. We related multisensory impairment to PA using multivariate mixed-effects linear regression and compared the effect magnitude after adjusting for physical then cognitive dysfunction. Worse multisensory impairment predicted lower PA across three scales (Global Sensory Impairment: β = -0.04, 95% confidence interval [-0.07, -0.02]; Total Sensory Burden: β = -0.01, 95% confidence interval [-0.03, -0.003]; and Number of Impaired Senses: β = -0.02, 95% confidence interval [-0.04, -0.004]). Effects were similar after accounting for physical and cognitive dysfunction. Findings suggest that sensory, physical, and cognitive dysfunction have unique mechanisms underlying their PA effects.