(160) Blood pressure levels in pregnancy and adverse maternal metabolic health 10-14 years postpartum

Guideline changes from the American College of Cardiology/American Heart Association (ACC/AHA) have shown that blood pressure (BP) < 140/90 increases the risk of adverse health in non-pregnant adults. We examined the associations between BP levels during pregnancy and long-term postpartum metabolic health.

Study Design: A secondary analysis from the prospective Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Follow-Up Study. The exposure was hypertension status in the early third trimester per ACC/AHA thresholds: normal BP < 120/80 mmHg (reference), elevated BP 120-129/< 80 mmHg, stage 1 hypertension 130-139/80-89 mmHg, and stage 2 hypertension ≥140/≥90 mmHg. Outcomes assessed 10-14 years after the index pregnancy were type 2 diabetes, prediabetes, metabolic syndrome, and measures of dyslipidemia. Modified Poisson models adjusted for baseline pregnancy covariates: field center, age, parity, BMI, height, family history of hypertension and diabetes, smoking and alcohol use, and OGTT summary z-score.

Results: Among 4,697 pregnant individuals in the early third trimester, 70.0% (n=3,290) had normal BP, 8.5% (n=399) had elevated BP, 14.9% (n=701) had stage 1 hypertension, and 6.4% (n=302) had stage 2 hypertension. At a median follow-up of 11.6 years, individuals with elevated BP (4.7%; aRR: 2.06; 95% CI: 1.51, 2.61), stage 1 hypertension (5.7%; aRR: 2.65; 95% CI: 2.20, 3.10), and stage 2 hypertension (9.2%; aRR: 2.87; 95% CI: 2.35, 3.39) were at greater risk of developing type 2 diabetes compared with those with normal BP (1.5%). Similarly, individuals with elevated BP, stage 1 hypertension, and stage 2 hypertension were at greater risk of developing prediabetes and metabolic syndrome. There was no increased risk between increasing BP category and LDL cholesterol, HDL cholesterol, and triglycerides.

Conclusion: Pregnant individuals with elevated BP ≥120/80 are at increased risk of adverse metabolic health 10-14 years postpartum. BP categories with lower thresholds (AHA/ACC) than those currently used for hypertension in pregnancy may identify individuals at risk for adverse long-term metabolic health.