Importance: There is no definitive evidence that changes in physical activity/sedentary behavior can be maintained long term in individuals with type 2 diabetes.
Objective: To investigate whether a behavioral intervention strategy can produce a sustained increase in physical activity and reduction in sedentary time among individuals with type 2 diabetes.
Design, setting, and participants: The Italian Diabetes and Exercise Study 2 was an open-label, assessor-blinded, randomized clinical superiority trial, with recruitment from October 2012 to February 2014 and follow-up until February 2017. In 3 outpatient diabetes clinics in Rome, 300 physically inactive and sedentary patients with type 2 diabetes were randomized 1:1 (stratified by center, age, and diabetes treatment) to receive a behavioral intervention or standard care for 3 years.
Interventions: All participants received usual care targeted to meet American Diabetes Association guideline recommendations. Participants in the behavioral intervention group (n = 150) received 1 individual theoretical counseling session and 8 individual biweekly theoretical and practical counseling sessions each year. Participants in the standard care group (n = 150) received only general physician recommendations.
Main outcomes and measures: Co-primary end points were sustained change in physical activity volume, time spent in light-intensity and moderate- to vigorous-intensity physical activity, and sedentary time, measured by an accelerometer.
Results: Of the 300 randomized participants (mean [SD] age, 61.6 [8.5] years; 116 women [38.7%]), 267 completed the study (133 in the behavioral intervention group and 134 in the standard care group). Median follow-up was 3.0 years. Participants in the behavioral intervention and standard care groups accumulated, respectively, 13.8 vs 10.5 metabolic equivalent-h/wk of physical activity volume (difference, 3.3 [95% CI, 2.2-4.4]; P < .001), 18.9 vs 12.5 min/dof moderate- to vigorous-intensity physical activity (difference, 6.4 [95% CI, 5.0-7.8]; P < .001), 4.6 vs 3.8 h/d of light-intensity physical activity (difference, 0.8 [95% CI, 0.5-1.1]; P < .001), and 10.9 vs 11.7 h/d of sedentary time (difference, -0.8 [95% CI, -1.0 to -0.5]; P < .001). Significant between-group differences were maintained throughout the study, but the between-group difference in moderate- to vigorous-intensity physical activity decreased during the third year from 6.5 to 3.6 min/d. There were 41 adverse events in the behavioral intervention group and 59 in the standard care group outside of the sessions; participants in the behavioral intervention group experienced 30 adverse events during the sessions (most commonly musculoskeletal injury/discomfort and mild hypoglycemia).
Conclusions and relevance: Among patients with type 2 diabetes at 3 diabetes clinics in Rome who were followed up for 3 years, a behavioral intervention strategy compared with standard care resulted in a sustained increase in physical activity and decrease in sedentary time. Further research is needed to assess the generalizability of these findings.
Trial registration: ClinicalTrials.gov Identifier: NCT01600937.