Do Hypertensive Disorders Raise Diabetes Risk?

Key Points

• Data from the Cohort of Cardiovascular Diseases in Pregnancy (CONCEPTION), a French prospective national cohort study, indicate that hypertension before or during pregnancy increases the risk for diabetes in the years following pregnancy, even in women who did not experience gestational diabetes.
• Women with chronic hypertension before pregnancy and those who developed preeclampsia during pregnancy are at highest risk.
• These findings underscore the importance of screening for gestational diabetes in all women who experienced hypertensive disorders during pregnancy.

Type 2 diabetes and hypertensive disorders during pregnancy are closely linked, according to epidemiological data, although the exact nature of this association remains unclear. There is evidence to suggest a bidirectional relationship between the two conditions. Hypertensive disorders in pregnant women can vary in severity, from preexisting hypertension to the development of abnormal blood pressure levels during pregnancy, with the most severe cases seeing a progression toward preeclampsia. This analysis also aimed to formally establish how the duration of these conditions could influence the risk for diabetes, as the current evidence on this topic is insufficient.

11-Year Study of 3 Million Women

The study was based on CONCEPTION, which included all women aged 15-49 years who delivered a baby after 22 weeks of pregnancy between 2010 and 2018. All were affiliated with the general health insurance system and had no history of gestational diabetes. Preexisting hypertension was identified based on the prescription of at least one antihypertensive medication before pregnancy. A determination of gestational hypertension was made if a prescription was initiated for the first time between the 20th week of pregnancy and the sixth week postpartum or if the patient had been hospitalized for hypertension during pregnancy. Preeclampsia, eclampsia, and HELLP syndrome were defined using hospital coding. The onset of diabetes during follow-up was established based on the dispensation of antidiabetic medications on three occasions within a 12-month period.

The study included data from 2,815,057 women (mean age, 28.8 years; 4.1% obesity; 8.9% smokers), of whom 1.2% had preexisting hypertension, 4.6% had gestational hypertension, and 2.6% had preeclampsia.

Hypertension and Preeclampsia: Highest Risk

After excluding women who had experienced gestational diabetes (8.4% of the initial cohort), the cumulative incidence of diabetes after 11 years of follow-up was 0.8% in women without hypertension, 1.7% in those with gestational hypertension, 2.1% in those with preeclampsia, 3.5% in those with preexisting hypertension, and 6.1% in those who had both preexisting hypertension and preeclampsia.

Compared with women without a history of hypertension and who did not develop diabetes, those with hypertensive disorders during pregnancy had a 2.36-fold increased risk for diabetes (adjusted hazard ratio [aHR], 2.36; 95% CI, 2.22-2.51). The highest risk was observed in women with preexisting hypertension before pregnancy (aHR, 3.35; 95% CI, 3.03-3.70).

An analysis of the risk based on the nature and severity of preeclampsia revealed that women at the greatest risk for diabetes were those who had early-onset preeclampsia (aHR, 2.73; 95% CI, 2.31-3.23), while those with the lowest risk had mild preeclampsia (aHR, 2.30; 95% CI, 2.04-2.60). However, among women who developed preeclampsia, those with preexisting hypertension were at a much higher risk for subsequent diabetes (aHR, 2.00; 95% CI, 1.78-2.24 and aHR, 3.95; 95% CI, 3.27-4.78, respectively).

Researchers also found that diabetes screening rates within the first year after pregnancy were insufficient among women who had experienced preeclampsia (38.9%) and even among those who had also had gestational diabetes (58.3%).

This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.