Changing chronic disease rates and long-term declines in functional limitation among older men.

Functional limitation (difficulty walking, difficulty bending, paralysis, blindness in at least one eye, or deafness in at least one ear) in the United States fell at an average annual rate of 0.6% among men aged 50 to 74 from the early twentieth century to the early 1990s. Twenty-four percent of this decline is attributable to reductions in the debilitating effects of chronic conditions, 37% is attributable to reduced rates of chronic diseases, and the remainder is unexplained. The findings have implications for theories of the impact of declining mortality rates on the health of elderly people.