Rationale, design, and cohort characteristics of the Action for Health in Diabetes Aging study

Introduction: Diabetes and overweight/obesity are described as accelerating aging processes, yet many individuals with these conditions maintain high levels of cognitive and physical function and independence late into life. The Look AHEAD Aging study is designed to identify 20-year trajectories of behaviors, risk factors, and medical history associated with resilience against geriatric syndromes and aging-related cognitive and physical functional deficits among individuals with these conditions.

Methods: Look AHEAD Aging extends follow-up of the cohort of the former 10-year Look AHEAD trial. The original cohort (N = 5145) was enrolled in 2001 to 2004 when participants were aged 45 to 76 years and randomly assigned to a multidomain intensive lifestyle intervention (ILI) or a diabetes support and education (DSE) condition. The trial interventions ceased in 2012. Clinic-based follow-up continued through 2020. In 2021, the cohort was invited to enroll in Look AHEAD Aging, an additional 4-year telephone-based follow-up (every 6 months) enhanced with Medicare linkage. Standardized protocols assess multimorbidity, physical and cognitive function, health care utilization, and health-related quality of life.

Results: Of the original N = 5145 Look AHEAD participants, N = 1552 active survivors agreed to participate in Look AHEAD Aging. At consent, the cohort's mean age was 76 (range 63 to 94) years and participants had been followed for a mean of 20 years. Of the original Look AHEAD enrollees, those who were younger, female, or with no history of cardiovascular disease were more likely to be represented in the Look AHEAD Aging cohort. Intervention groups were comparable with respect to age, diabetes duration, body mass index, insulin use, hypertension, cardiovascular disease, and cognitive function. ILI participants had significantly lower deficit accumulation index scores.

Discussion: By continuing the long-term follow-up of an extensively characterized cohort of older individuals with type 2 diabetes, Look AHEAD Aging is well positioned to identify factors associated with resilience against aging-related conditions.