ObjectiveTo estimate and compare progression rates to type 2 diabetes mellitus (T2DM) in women with gestational diabetes mellitus (GDM) and healthy controls.DesignSystematic review and meta-analysis.Data sourcesMedline and Embase between January 2000 and December 2019, studies published in English and conducted on humans.Eligibility criteria for selecting studiesObservational studies investigating progression to T2DM. Inclusion criteria were postpartum follow-up for at least 12 months, incident physician based diagnosis of diabetes, T2DM reported as a separate outcome rather than combined with impaired fasting glucose or impaired glucose tolerance, and studies with both a group of patients with GDM and a control group.ResultsThis meta-analysis of 20 studies assessed a total of 1 332 373 individuals (67 956 women with GDM and 1 264 417 controls). Data were pooled by random effects meta-analysis models, and heterogeneity was assessed by use of the I2 statistic. The pooled relative risk for the incidence of T2DM between participants with GDM and controls was estimated. Reasons for heterogeneity between studies were investigated by prespecified subgroup and meta-regression analyses. Publication bias was assessed by funnel plots and, overall, studies were deemed to have a low risk of bias (P=0.58 and P=0.90). The overall relative risk for T2DM was almost 10 times higher in women with previous GDM than in healthy controls (9.51, 95% confidence interval 7.14 to 12.67, P<0.001). In populations of women with previous GDM, the cumulative incidence of T2DM was 16.46% (95% confidence interval 16.16% to 16.77%) in women of mixed ethnicity, 15.58% (13.30% to 17.86%) in a predominantly non-white population, and 9.91% (9.39% to 10.42%) in a white population. These differences were not statistically significant between subgroups (white v mixed populations, P=0.26; white v non-white populations, P=0.54). Meta-regression analyses showed that the study effect size was not significantly associated with mean study age, body mass index, publication year, and length of follow-up.ConclusionsWomen with a history of GDM appear to have a nearly 10-fold higher risk of developing T2DM than those with a normoglycaemic pregnancy. The magnitude of this risk highlights the importance of intervening to prevent the onset of T2DM, particularly in the early years after pregnancy.Systematic review registrationPROSPERO CRD42019123079.

Objective: To examine the association of comorbid occurrence of diabetes and depression with risk of cardiovascular endpoints including cardiovascular mortality, coronary heart disease and stroke. Research Design and Methods:A systematic review and metaanalysis. We searched PUBMED/MEDLINE, Medscape, Cochrane Library, CINAHL, EMBASE and Scopus databases assessing cardiac events and mortality associated with depression in diabetes up until 1 December 2018. Pooled hazard ratios were calculated using random-effects models.Results: Nine studies met the inclusion criteria. The combined pooled hazard ratios showed a significant association of cardiac events in people with depression and type 2 diabetes, compared to those with type 2 diabetes alone. For cardiovascular mortality the pooled hazard ratio was 1.48 (95% CI: 1.185, 1.845), p=0.001, for coronary heart disease 1.37 (1.165, 1.605), p<0.001 and for stroke 1.33 (1.291, 1.369), p<0.001. Heterogeneity was high in the meta-analysis for stroke events (I-squared = 84.7%) but was lower for coronary heart disease and cardiovascular mortality (15% and 43.4% respectively). Meta-regression analyses showed that depression was not significantly associated with the study level covariates mean age, duration of diabetes, length of follow-up, BMI, sex and ethnicity (p<0.05 for all models). Only three studies were found that examined the association of depression in type 1 diabetes, there was a high degree of heterogeneity and data synthesis was not conducted for these studies. Conclusions:We have demonstrated a 47.9% increase in cardiovascular mortality, 36.8% increase in coronary heart disease and 32.9% increase in stroke in people with diabetes and comorbid depression. The presence of depression in a person with diabetes should trigger the consideration of evidencebased therapies for cardiovascular disease prevention irrespective of the baseline risk of cardiovascular disease or duration of diabetes.