Declines in Mobility and Changes in Performance in the Instrumental Activities of Daily Living Among Mildly Disabled Community-Dwelling Older Adults

Background. Gait speed is as an important predictor of mortality, volume of medical care, hospitalization, onset of activities of daily living (ADL) disability, and nursing home placement. We examined associations between change in gait speed and change in observed performance in the instrumental ADL (IADL) in a sample of mild-to-moderately disabled older adults. Methods. Participants in the Sources of Independence in the Elderly project (n = 375) were approached to complete a 4-m gait assessment and a performance test of IADL competency at three points over 2 years. IADL competency was assessed by occupational therapists, who rated participants using the Assessment of Motor and Process Skills (AMPS) and who also made a global rating of need for help or supervision. Linear mixed models were developed to assess change in motor AMPS score relative to baseline status and change in gait speed and AMPS process scores. Results. Baseline gait and change in gait were significant correlates of change in the AMPS motor ability measures in models that adjusted for cognitive status and AMPS process ability. Even respondents with gait speeds of 1 m/s at baseline were at risk of declining AMPS motor ability and an occupational therapist rating of IADL disability if gait speed declined. Conclusions. Slowing in gait speed is an important risk factor for IADL disability in mild to moderately disabled older adults.