Lifestyle Intervention Strategy to Treat Diabetes in Older Adults: A Randomized Controlled Trial.

OBJECTIVE: Lifestyle intervention is recommended as first-line treatment of diabetes at all ages; however, little is known about the efficacy of lifestyle intervention in older adults with diabetes. We aimed to determine whether lifestyle intervention would improve glycemic control and age-relevant outcomes in older adults with diabetes and comorbidities. RESEARCH DESIGN AND METHODS: A total of 100 older adults with diabetes were randomly assigned to 1-year intensive lifestyle intervention (ILI) (diet and exercise at a facility transitioned into community-fitness centers and homes) or healthy lifestyle (HL) group. The primary outcome was change in HbA1c. Secondary outcomes included glucoregulation, body composition, physical function, and quality of life. Changes between groups were analyzed with mixed-model repeated-measures ANCOVA following the intention-to-treat principle. RESULTS: HbA1c improved more in the ILI than the HL group (mean ± SE -0.8 ± 0.1 vs. 0.1 ± 0.1%), associated with improved insulin sensitivity (1.2 ± 0.2 vs. -0.4 ± 0.2) and disposition (26.0 ± 8.9 vs. -13.0 ± 8.4 109 min-1) indices (between-group P < 0.001 to 0.04). Body weight and visceral fat decreased more in the ILI than HL group (-8.4 ± 0.6 vs. -0.3 ± 0.6 kg, P < 0.001, and -261 ± 29 vs. -30 ± 27 cm3, P < 0.001, respectively). Physical Performance Test score increased more in the ILI than HL group (2.9 ± 0.6 vs. -0.1 ± 0.4, P < 0.001) as did VO2peak (2.2 ± 0.3 vs. -1.2 ± 0.2 mL/kg/min, P < 0.001). Strength, gait, and 36-Item Short Form Survey (SF-36) Physical Component Summary score also improved more in the ILI group (all P < 0.001). Total insulin dose decreased in the ILI group by 19.8 ± 4.4 units/day. Adverse events included increased episodes of mild hypoglycemia in the ILI group. CONCLUSIONS: A lifestyle intervention strategy is highly successful in improving metabolic and functional health of older adults with diabetes.