The effect of self-reported and performance-based functional impairment on future hospital costs of community-dwelling older persons

We determined the prognostic value of self-reported and performance-based measurement of function, including functional transitions and combining different measurement approaches, on utilization.

Our cohort study used the 6th, 7th, and 10th waves of three sites of the Established Populations for Epidemiologic Studies of the Elderly, linked to 1- and 4-year Medicare Part A hospital costs. We examined mean hospital expenditures based on (a) 1- and 4-year transitions in self-reported functional status; (b) 4-year transitions in performance-based functional status; (c) combined baseline self-reported and performance-based functional status; and (d) poorest self-reported and performance-based functional status during a 4-year period.

Even modest declines in self-reported or performance-based functional status were associated with increased expenditures. When baseline self-reported and performance-based assessments were combined, mean 1- and 4-year adjusted costs were higher with progressively worse performance-based scores, even among those who were independent in self-reported function. When the poorest 4-year self-reported and performance-based functions were examined, self-reported functioning was the most important determinant of hospital costs, but within each self-reported functional level, poorer performance-based function was associated with progressively higher costs.

The costs associated with even modest functional decline are high. Combining self-reported and performance-based measurements can provide more precise estimates of future hospital costs.