Correction: Increased risk of ischemic heart disease, hypertension, and type 2 diabetes in women with previous gestational diabetes mellitus, a target group in general practice for preventive interventions: A population-based cohort study.

[This corrects the article DOI: 10.1371/journal.pmed.1002488.].

Serum testosterone, sex hormone-binding globulin and sex-specific risk of incident type 2 diabetes in a retrospective primary care cohort.

OBJECTIVE: Previous studies suggest that androgens have a sexually dimorphic impact on metabolic dysfunction. However, the sex-specific link between circulating androgens and risk of type 2 diabetes mellitus (T2DM) has not been examined in a large scale, longitudinal cohort, a task we undertook in this study. DESIGN: A retrospective cohort study in a UK primary care database. PATIENTS: We included men and women with available serum testosterone and sex hormone-binding globulin (SHBG) results. MEASUREMENTS: We categorized serum concentrations according to clinically relevant cut-off points and calculated crude and adjusted T2DM Incidence Rate Ratios (IRRs and aIRRs). RESULTS: Serum testosterone concentrations were available in 70 541 men and 81 889 women; serum SHBG was available in 15 907 men and 42 034 women. In comparison to a reference cohort with serum testosterone ≥20 nmol/L, men with lower serum testosterone had a significantly increased risk of T2DM, with the highest risk in those with serum testosterone <7 nmol/L (aIRR 2.71, 95% CI 2.34-3.14, P < 0.001). In women, the risk of T2DM started to increase significantly when serum testosterone concentrations exceeded 1.5 nmol/L, with the highest risk in women with serum testosterone ≥3.5 nmol/L (aIRR 1.98, 95% CI 1.55-2.52, P < 0.001). These observations were verified in a continuous rather than categorized analysis. The risk of T2DM increased in men and women with serum SHBG <40 and <50 nmol/L, respectively. CONCLUSIONS/INTERPRETATION: In this longitudinal study, we found sexually dimorphic associations between serum testosterone and risk of incident T2DM. Androgen deficiency and excess should be considered important risk factors for diabetes in men and women, respectively.

Increased risk of ischemic heart disease, hypertension, and type 2 diabetes in women with previous gestational diabetes mellitus, a target group in general practice for preventive interventions: A population-based cohort study.

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with developing type 2 diabetes, but very few studies have examined its effect on developing cardiovascular disease. METHODS AND FINDINGS: We conducted a retrospective cohort study utilizing a large primary care database in the United Kingdom. From 1 February 1990 to 15 May 2016, 9,118 women diagnosed with GDM were identified and randomly matched with 37,281 control women by age and timing of pregnancy (up to 3 months). Adjusted incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated for cardiovascular risk factors and cardiovascular disease. Women with GDM were more likely to develop type 2 diabetes (IRR = 21.96; 95% CI 18.31-26.34) and hypertension (IRR = 1.85; 95% CI 1.59-2.16) after adjusting for age, Townsend (deprivation) quintile, body mass index, and smoking. For ischemic heart disease (IHD), the IRR was 2.78 (95% CI 1.37-5.66), and for cerebrovascular disease 0.95 (95% CI 0.51-1.77; p-value = 0.87), after adjusting for the above covariates and lipid-lowering medication and hypertension at baseline. Follow-up screening for type 2 diabetes and cardiovascular risk factors was poor. Limitations include potential selective documentation of severe GDM for women in primary care, higher surveillance for outcomes in women diagnosed with GDM than control women, and a short median follow-up postpartum period, with a small number of outcomes for IHD and cerebrovascular disease. CONCLUSIONS: Women diagnosed with GDM were at very high risk of developing type 2 diabetes and had a significantly increased incidence of hypertension and IHD. Identifying this group of women in general practice and targeting cardiovascular risk factors could improve long-term outcomes.