Use of antihypertensive medications during delivery among women with preeclampsia increased significantly over the past decade, an administrative database study showed.
Almost half of patients with preeclampsia received antihypertensive medication in 2015 — a substantial increase versus 2006, when only 37.8% received such medication (P<0.01), reported Kristen Cleary, MD, of Columbia University in New York City, and colleagues.
Moreover, the rate of stroke in patients with preeclampsia declined from 6.6 per 10,000 deliveries in 2006-2008 to 3.5 per 10,000 deliveries in 2012-2014 (P=0.02), the authors wrote in Obstetrics and Gynecology.
They noted that the American College of Obstetricians and Gynecologists’ (ACOG) Task Force on Hypertension in Pregnancy supports administering antihypertensive agents for preeclampsia with severe features with sustained blood pressure of 160 mm Hg or 110 mm Hg systolic and diastolic, respectively. First-line agents for acute hypertension in this population include IV beta-blocker labetalol, IV vasodilator hydralazine, and oral calcium channel blocker nifedipine, they said.
But the authors added that there is “limited research on how practice patterns are changing” and to what degree antihypertensive agents are being used to treat hypertensive episodes, as well as little data on how they are associated with improved outcomes.
They looked at data from the Perspective database to determine use of antihypertensive drugs dispensed during delivery hospitalizations complicated by preeclampsia. The database includes patient demographics, hospital characteristics, discharge diagnosis codes, and medications and devices administered during acute care hospitalizations. Notably, the authors said discharges in the Perspective database account for “approximately 15% of all inpatient hospital stays annually in the United States.”
From January 2006 to March 2015, researchers examined data from 239,000 women admitted for a delivery hospitalization with an associated preeclampsia diagnosis. Based on ICD-9-CM codes, they were categorized as having mild (n=126,000), severe (n=81,000), or superimposed (n=32,000) preeclampsia.
The authors noted that over the course of the study, the portion of patients increased for both severe preeclampsia (36.9% of cases in 2015 versus 30.9% in 2006) and superimposed preeclampsia (15.7% versus 10.3%, respectively). Notably, superimposed preeclampsia was more common in the southern region of the U.S., among black women, and among women ages 35 and older.
Use of individual hypertensive agents increased over the course of the study from 2006 to 2014, as well:
- Oral labetalol (20.3% to 31.4%)
- IV labetalol (13.3% to 21.4%)
- Hydralazine (12.8% to 16.9%)
- Nifedipine (15.0% to 18.2%)
- More than one medication (16.5% to 25.8%)
Adjusted analyses found that the likelihood of antihypertensive use rose (adjusted RR 1.19, 95% CI 1.12-1.27 in 2015 versus 2006). Severe and superimposed preeclampsia were associated with the largest increase in likelihood of antihypertensive medication use (adjusted RR 2.19, 95% CI 2.12-2.26, and adjusted RR 2.32, 95% CI 2.23-2.41, respectively). The authors said that other significant factors included black race (adjusted RR 1.30 versus white race, 95% CI 1.27-1.33) and maternal age 35 years or older (adjusted RR 1.17 versus age 18-24, 95% CI 1.15-1.19).
Not surprisingly, the rate of stroke was highest among patients with severe preeclampsia, but that declined sharply from 13.5 per 10,000 deliveries in 2006-2008 to 6.0 per 10,000 deliveries in 2012-2014.
Limitations to the study included use of only administrative data and lack of information on how individual hospital factors may have impacted the results. In addition, though the data showed that a drug was ordered and administered, the authors could not determine if it occurred in a “timely, optimal fashion” and if treatment in a specific time interval improved outcomes. Nor could they not establish a causal relationship between antihypertensive medication and risk for stroke.
Cleary disclosed no conflicts of interest.
One co-author disclosed support from the Eunice Kennedy Shriver National Institute of Child Health and Human Development.
Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, BSN, RN, Nurse Planner