Weight, mortality, years of healthy life, and active life expectancy in older adults

Abstract

Objectives: To determine whether weight categories predict subsequent mortality and morbidity in older adults.

Design: Multistate life tables, using data from the Cardiovascular Health Study, a longitudinal population-based cohort of older adults.

Setting: Data were provided by community-dwelling seniors in four U.S. counties: Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Allegheny County, Pennsylvania.

Participants: Five thousand eight hundred eighty-eight adults aged 65 and older at baseline.

Measurements: The age- and sex-specific probabilities of transition from one health state to another and from one weight category to another were estimated. From these probabilities, future life expectancy, years of healthy life, active life expectancy, and the number of years spent in each weight and health category after age 65 were estimated.

Results: Women who are healthy and of normal weight at age 65 have a life expectancy of 22.1 years. Of that, they spend, on average, 9.6 years as overweight or obese and 5.3 years in fair or poor health. For both men and women, being underweight at age 65 was associated with worse outcomes than being normal weight, whereas being overweight or obese was rarely associated with worse outcomes than being normal weight and was sometimes associated with significantly better outcomes.

Conclusion: Similar to middle-aged populations, older adults are likely to be or to become overweight or obese, but higher weight is not associated with worse health in this age group. Thus, the number of older adults at a "healthy" weight may be much higher than currently believed.

Figure 1

Projected Health Trajectory over Time . Number of people in hypothetical cohort of 100,000 65-year-old healthy normal-weight women, with future health status estimated from multi-state life tables.

Figure 2

Projected BMI Trajectory over Time . Number of people in hypothetical cohort of 100,000 65-year-old healthy normal-weight women, with future BMI states estimated from multi-state life tables.