Can slight glucose intolerance during pregnancy predict future maternal atherosclerotic morbidity?

Aim: o examine the association between glucose level during pregnancy and the subsequent development of long-term maternal atherosclerotic morbidity. Methods: A retrospective case–control study was conducted. The study included all women who had at least one glucose measurement during their pregnancies. Cases were all women who delivered between the years 2000–2012 and subsequently developed atherosclerotic morbidity (n = 815). Controls were randomly matched by age and year of delivery (n = 6065). The atherosclerotic morbidity group was further divided by severity: major events (cardiovascular, cerebrovascular disease, chronic renal failure), minor events (hypertension, diabetes mellitus and hyperlipidaemia without target organ damage or complications) and cardiac evaluation tests (such as coronary angiography without records of atherosclerosis, cardiac scan and stress test). The mean follow-up duration for the study group was 74 months. Cox proportional hazards model was used to control for confounders. Results: A significant linear association was found between glucose levels during pregnancy and long-term maternal atherosclerotic morbidity. Among the cases with severe atherosclerotic morbidity, the proportion of women with a high glucose level (> 5.5 mmol/l) was the highest, whereas in controls it was the lowest (P < 0.001). In a Cox proportional hazard model, adjusted for atherosclerotic confounders such as gestational diabetes, pre-eclampsia and obesity, a glucose level of > 5.5 mmol/l was noted as an independent risk factor for hospitalizations later in non-pregnant life (hazard ratio = 1.3, 95% confidence interval 1.1–1.5, P < 0.003). Conclusion: A high glucose level during pregnancy, even if within the range of slight glucose intolerance, may serve as a marker for future maternal atherosclerotic morbidity. Further long-term studies are needed to confirm our findings.