Little is known about the varying degrees of functional decline associated with certain conditions alone or in combination with other conditions. Kiely and colleagues conducted a longitudinal study to assess how functional decline varies among patients with heart disease, arthritis, diabetes, cancer and stroke, either alone or in combination.

Elderly persons living in the community and residents of a home care program participated in this study. The study subjects ranged in age from 69 to 101 years (median age: 86 years). A baseline assessment and two annual follow-up assessments were conducted. Almost all of the study subjects were interviewed by telephone. A functional dependency index was calculated from each person's scores on activities of daily living and on instrumental activities of daily living. An increase in the functional dependency index was considered a functional decline.

Of the 1,060 patients initially interviewed, 931 (87.8 percent) completed the first follow-up assessment and 822 (77.5 percent) completed the second assessment. During the first interview, 65 percent of the patients reported having arthritis; 37 percent, heart disease; 15 percent, diabetes mellitus; 11 percent, stroke; and 8 percent, cancer.

Functional decline occurred throughout the study period: 53.2 percent were independent at baseline, 47.1 percent were independent at the one-year assessment, and 40.6 percent remained independent at the two-year assessment. The rate of decline did not differ significantly among the patients with different medical conditions. However, a significant decline in functional status occurred with each additional diagnosis in an individual patient. Stroke, the condition most strongly associated with functional impairment, was comparable to a five-year maturational decline. Coexistent heart disease and diabetes mellitus compared with a two-year maturational decline, and the presence of arthritis and cancer was comparable to a one-year maturational decline.

The authors conclude that prevention of certain medical conditions, particularly stroke, is necessary to maintain a patient's functional level. They propose further research to determine whether aggressive rehabilitation programs initiated immediately after the diagnosis of one of the conditions studied can prevent the functional decline associated with the condition.