Am J Clin Nutr. 2026 Mar 18:101282. doi: 10.1016/j.ajcnut.2026.101282. Online ahead of print.
ABSTRACT
BACKGROUND: Body weight is a critical determinant of cardiovascular risk among people with type 2 diabetes mellitus (T2DM), substantially contributing to the incidence of and outcomes from cardiovascular disease (CVD). However, the impact of body weight on the effectiveness of digital health interventions, an increasingly used innovation to improve care outcomes, remains uncertain.
OBJECTIVE: To examine the effectiveness of digital health interventions in improving cardiovascular risks and whether baseline body mass index (BMI) modified these effects in people with T2DM.
METHODS: SMARTDiabetes was an open-label, parallel, cluster randomized controlled trial examining the effects of digital health interventions versus usual care on T2DM management over 24 months. In this secondary analysis, we compared 10-year CVD risk scores between intervention and usual care groups and examined the heterogeneity of intervention effects across different BMI subgroups.
RESULTS: The study included 2,072 patients with T2DM of whom 714 were in the normal BMI range (<25 kg/m2), 996 overweight (25 to <30 kg/m2), and 362 obese (≥30 kg/m2) at baseline. There was no difference in mean 10-year CVD risk between intervention and usual care groups from baseline to 24 months (between-group difference: -0.201%, 95% CI -0.788,1.190; p=0.691). However, there was significant heterogeneity by BMI subgroup (p interaction=0.009). Among individuals with normal BMI, the intervention was associated with a significant reduction in mean 10-year CVD risk (-1.108% [95% CI -1.831, -0.386; p=0.003]), whereas no significant benefit was observed in overweight or obese individuals. A similar heterogeneity of intervention effects was observed for change in body weight and systolic blood pressure (p interaction <0.1 for all comparisons).
CONCLUSIONS: Digital health interventions had heterogeneous effects on reducing cardiovascular risk and were only effective among people with a normal baseline BMI. Digital health interventions should be tailored to better suit the needs for people with T2DM and elevated BMI.
REGISTRATION ID: NCT02726100, URL:https://ichgcp.net/clinical-trials-registry/NCT02726100.
PMID:41862002 | DOI:10.1016/j.ajcnut.2026.101282