Six-year follow-up of glycemic control and cardiovascular risk factors after a one-year intensive lifestyle intervention in type 2 diabetes: An extension of the randomized U-TURN trial

PURPOSE: This study aimed to describe the effects of a 1-year lifestyle intervention on hemoglobin A1c (HbA1c) and cardiovascular risk factors 5 years after cessation of the lifestyle intervention in persons with type 2 diabetes (T2D). METHODS: From April 2015 to August 2016, 98 persons with T2D (duration < 10 years) were randomly allocated (2:1, stratified by sex) to a 1-year lifestyle intervention group (INT) (n = 64) or a standard care group (StC) (n = 34). All participants received standard care with blinded, target-driven medical therapy. INT included up to 5-6 weekly supervised aerobic and strength training sessions and dietary plans targeting a body mass index ≤ 25 kg/m². No intervention was given during the follow-up period. Forty-nine (77%) and 19 (56%) participants in INT and StC attended the 6-year follow-up. Based on the original intention-to-treat population, the primary outcome was the change in HbA1c from baseline to 6-year follow-up. Secondary outcomes included weight, Low density lipoprotein (LDL) cholesterol, blood pressure (BP), and cardiorespiratory fitness. RESULTS: Ninety-eight participants (mean age = 54.6 years; 46% women; mean baseline Hemoglobin A1c (HbA1c) = 49.8 mmol/mol) were analyzed. HbA1c changed 6% and 13% in the INT and StC from baseline to 6-year follow-up (between group difference = -6% (95% confidence interval(95%CI): -14% to 3%); p = 0.18). While no differences were observed for most secondary outcomes, the diastolic BP decreased 6.0 (95%CI: 2.1 to 9.8) mmHg more in the StC compared to INT. CONCLUSION: The sustained effect of the lifestyle intervention on glycemic control and cardiovascular risk factors was marginal, and it was surprisingly associated with inferior diastolic BP regulation.