Patients with type 2 diabetes (T2D) who undergo an intensive lifestyle intervention for weight loss may experience fewer cardiovascular events, but some may face greater cardiovascular risk, according to study results published in Diabetes Care.
Researchers conducted this post hoc analysis of the Action for Health in Diabetes (Look AHEAD; ClinicalTrials.gov Identifier: NCT00017953) trial to investigate a potential heterogeneous effect of an intensive lifestyle weight loss intervention on the occurrence of major cardiovascular events in patients with T2D and overweight or obesity.
A penalized Cox regression model was used to predict treatment effect of intensive lifestyle intervention for cardiovascular event risk for 4901 participants from the Look AHEAD trial. Patients were randomly assigned to intensive lifestyle intervention or a diabetes education program in Look AHEAD, and for this analysis, patients who received the lifestyle intervention were stratified to quartiles for predicted treatment effect. Based on baseline characteristics, patients in quartile 1 were expected to have the greatest reduction in cardiovascular risk from the treatment, while those in quartile 4 were predicted to experience a harmful effect.
On average, patients were 59 years old and had a mean body mass index of 36 kg/m2 and median diabetes duration of 5 years. Median follow-up time was 9.4 years, during which 799 major cardiovascular events occurred.
There was good agreement between the predicted and observed risk for major cardiovascular events across the quartiles: quartile 1 benefitted significantly from the lifestyle intervention (hazard ratio [HR], 0.64), whereas quartiles 2 and 3 experienced no significant treatment effects (HRs, 0.81 and 1.13, respectively) and quartile 4 experienced detrimental effects from the lifestyle intervention (HR, 1.37).
Several patient characteristics were associated with potential treatment benefits, including no history of cardiovascular disease, good control of T2D, no insulin use, higher socioeconomic status, and absence of macroalbuminuria.
In summarizing their findings, the authors said, “[f]uture research into intensive lifestyle weight loss interventions for [cardiovascular disease] risk reduction should be specifically aimed on the one hand at subgroups of patients with a higher likelihood of treatment benefit and on the other hand at finding safe lifestyle interventions for subgroups of patients with a potential treatment harm.”
de Vries TI, Dorresteijn JAN, van der Graaf Y, Visseren FLJ, Westerink J. Heterogeneity of treatment effects from an intensive lifestyle weight loss intervention on cardiovascular events in patients with type 2 diabetes: data from the Look AHEAD trial [published online August 15, 2019]. Diabetes Care. doi:10.2337/dc19-0776