Changes in Physical and Cognitive Function Predict Sedentary Behavior in Older Adults With Mild Cognitive Impairment.

The current longitudinal study examined the influence of cognitive and lower extremity function on sedentary behavior continuously over 6 months in community-dwelling older adults with mild cognitive impairment (MCI). Multilevel models examined Montreal Cognitive Assessment (MoCA) change scores and the Short Physical Performance Battery (SPPB) on percent time in sedentary behavior among 17 older adults with MCI (50 to 74 observations for analysis). Sedentary behavior was measured daily and averaged monthly using wrist-worn actigraphy. Each 1-unit decrease in MoCA score was associated with an increase of 2 percentage points in sedentary behavior ( ≤ 0.01). In addition, each 1-unit decrease in chair stand score (lower extremity strength) was associated with an increase of 5 percentage points in sedentary behavior ( ≤ 0.01). Older adults experiencing cognitive decline and concurrent changes in lower extremity strength had the sharpest increase in sedentary behavior. Findings suggest lower body strengthening interventions may reduce sedentary behavior time and subsequently preserve physical functioning in this vulnerable population. [(6), 285-291.].