Lifestyle Intervention for the Prevention of Diabetes in Women With Previous Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

Background: Type 2 diabetes is increasing among the young, and gestational diabetes (GDM) offers a unique opportunity for diabetes prevention. We aimed to systematically review postpartum randomized trials to summarize the benefits of lifestyle interventions for women with previous GDM. Methods: We searched for RCTs involving women with previous GDM that compared lifestyle interventions-diet, physical activity or breastfeeding-at postpartum with usual care up to May 2018. Results: Of 1,895 abstracts identified, we selected 15 studies investigating incidence of diabetes or changes in glycemia. Most interventions focused on changes in diet and physical activity, only one also on incentive to breastfeeding. Meta-analysis of 8 studies investigating incidence of diabetes revealed a homogeneous (I-2 = 10%), reduction of 25% (RR = 0.75; 95% CI: 0.55-1.03) borderline statistically significant. Only trials offering intervention soon after delivery (< 6 months post-partum) were effective (RR = 0.61; 95% CI: 0.40-0.94; p for subgroup comparison = 0.11). Overall, no benefit was found regarding measures of glycemia. Although moderate reductions in weight (MD = -1.07 kg; -1.43-0.72 kg); BMI (MD = -0.94 kg/m(2); -1.79-0.09 kg/m(2)); and waist circumference (MD = -0.98 cm; -1.75-0.21 cm) were observed, effects were larger with longer follow-up. Conclusions: Summary results of the available evidence support benefits of lifestyle interventions at postpartum for women with previous GDM. Benefits, although smaller than those of major trials based in older subjects receiving intensive interventions, appear clinically relevant for this young subset of woman. Further studies are needed to improve the quality of the evidence and to further tailor interventions to this specific setting.