THE RELATIONSHIP BETWEEN PHYSICAL PERFORMANCE-MEASURES AND INDEPENDENCE IN INSTRUMENTAL ACTIVITIES OF DAILY LIVING

OBJECTIVES: Understanding the relationship between physical capacity a nd functional status is required to design exercise interventions to m aintain independent living. This study assessed the importance of phys ical performance in maintaining independence in Instrumental Activitie s of Daily Living (IADL). DESIGN: A pre-planned meta-analysis of cross -sectional data from six sites of the Frailty and Injury: Cooperative Studies of Intervention Trials (FICSIT). Linear regression was used to estimate the relationship between physical performance and IADL. PART ICIPANTS: 2190 community-dwelling older subjects. MEASUREMENTS: IADL w as the dependent variable; gait velocity, balance function, grip stren gth and chair rise time were the predictor variables. Age, gender, edu cation, falls self-efficacy, and cognitive status were covariates. RES ULTS: Gait velocity, balance function, and grip strength were independ ently related to IADL deficits, after correcting for covariates. The l inear slopes were relatively steep. For gait, a decrease of 0.1 m s(-1 ) was associated with 0.10 (95% CI: 0.17, 0.04) increase in IADL defic its, which is equivalent to I ADL deficit in 10 subjects. The linear s lopes for hand grip and balance were similar or steeper. In the sites where chair stand time was measured, an increase of 1 second in the ti me to rise was associated with a 0.14 (0.04, 0.24) increase in IADL de ficits. The relationships found in the meta-analytic analysis were con sistent across sites which enrolled subjects with widely varying level s of physical performance. CONCLUSION: Simple measures of physical per formance were strongly associated with IADL independence after correct ing for many previously identified predictors of functional status. Th e data from this meta-analysis support testing interventions designed to improve physical performance to determine whether improved performa nce can maintain or improve independence in IADLs.