Abstract
BACKGROUND: The rise in the number and earlier age of onset of obese persons has raised critical concerns about consequences of obesity; however, recent evidence suggests that the impact of obesity on health outcomes may have changed. This study aims to assess the change of the impact of obesity on active life expectancy among Americans aged 70 years and older over almost two decades, 1993-1998 to 2010-2014. METHODS: For each period, we use three waves of data from the Health and Retirement Study to estimate age-specific transition probabilities between health states. The average number of years active and disabled is calculated with Interpolated Markov Chain software based on estimated transition probabilities. RESULTS: Overall obesity and severe obesity increased markedly over time yet active life expectancy expanded for all individuals and the increases are greater among the obese and women. Increases in total and active life expectancy occurred because of the changing association of obesity with disability and mortality. CONCLUSIONS: Individuals at age 70 years in the later period in each weight group could expect to live a smaller proportion of remaining life with activities of daily living disability than those in the earlier period. High levels of obesity continue to have significant adverse effects on the quality of life. The increasing prevalence of severe obesity and the growing number of older persons may result in substantial additional health care needs and costs. Continued effort to improve cardiovascular health is required to control the burden of obesity in later life in an era of rising obesity.