Perinatal & Pediatric
Comparative effectiveness and safety of labetalol and nifedipine for the treatment of chronic hypertension during pregnancy Stephanie A. Leonard* Stephanie Leonard Sara Siadat Krista F. Huybrechts Elliott K. Main Mark A. Hlatky Brian T. Bateman
Clinical guidelines for treatment of chronic hypertension in pregnancy recommend labetalol and nifedipine as first-line agents. We used a target trial framework to evaluate the comparative effectiveness and safety of labetalol (an alpha/beta blocker) versus nifedipine (a calcium-channel blocker) in treatment of chronic hypertension in pregnancy. Study data for individuals with live- and stillbirths were sourced from the U.S. MerativeTM Marketscan® Database of commercial insurance claims for 2007 to 2022. The primary effectiveness outcome was a composite of preeclampsia with severe features or eclampsia, medically indicated preterm birth, placental abruption, or stillbirth. The primary safety outcome was infant born small-for-gestational age. We used log-binomial regression models to estimate associations between the treatment and outcomes, using stabilized inverse probability of treatment weights to adjust for confounding by year, gestational age at treatment initiation, maternal age, region, comorbidities, and other medications. The study included 6,784 pregnant individuals with chronic hypertension who initiated labetalol or nifedipine treatment during the first 20 weeks of pregnancy. Of these, 5,553 (82%) used labetalol and 1,231 (18%) used nifedipine. The composite effectiveness outcome occurred in 42% of births exposed to labetalol and 43% of births exposed to nifedipine. The safety outcome occurred in 13% of births exposed to labetalol and 12% of births exposed to nifedipine. Comparing nifedipine with labetalol, the adjusted risk ratio (RR) was 1.03 (95% confidence interval (CI): 0.96, 1.11) for the composite effectiveness outcome and 0.98 (95% CI: 0.82, 1.16) for the safety outcome. These results, using a cohort nested in nationwide healthcare utilization data, suggest that labetalol and nifedipine have comparable effectiveness and safety when used for the treatment of chronic hypertension during pregnancy.