Impact of an 8-Year Intensive Lifestyle Intervention on an Index of Multimorbidity

BACKGROUND/OBJECTIVES: Type 2 diabetes mellitus and obesity are sometimes described as conditions that accelerate aging. Multidomain lifestyle interventions have shown promise to slow the accumulation of age-related diseases, a hallmark of aging. However, they have not been assessed among at-risk individuals with these two conditions. We examined the relative impact of 8 years of a multidomain lifestyle intervention on an index of multimorbidity. DESIGN: Randomized controlled clinical trial comparing an intensive lifestyle intervention (ILI) that targeted weight loss through caloric restriction and increased physical activity with a control condition of diabetes support and education (DSE). SETTING: Sixteen U.S. academic centers. PARTICIPANTS: A total of 5,145 volunteers, aged 45 to 76, with established type 2 diabetes mellitus and overweight or obesity who met eligibility criteria for a randomized controlled clinical trial. MEASUREMENTS: A multimorbidity index that included nine age-related chronic diseases and death was tracked over 8 years of intervention delivery. RESULTS: Among individuals assigned to DSE, the multimorbidity index scores increased by an average of.98 (95% confidence interval [CI] =.94–1.02) over 8 years, compared with.89 (95% CI =.85–.93) among those in the multidomain ILI, which was a 9% difference (P =.003). Relative intervention effects were similar among individuals grouped by baseline body mass index, age, and sex, and they were greater for those with lower levels of multimorbidity index scores at baseline. CONCLUSIONS: Increases in multimorbidity over time among adults with overweight or obesity and type 2 diabetes mellitus may be slowed by multidomain ILI. J Am Geriatr Soc 68:2249–2256, 2020.