As-Needed Blood Pressure Medication and Adverse Outcomes in VA Hospitals.

Abstract

Importance: Asymptomatic blood pressure (BP) elevations in the hospital are commonly treated with as-needed BP medications, including recurring as-needed and 1-time administration. Veterans represent a population at risk of ischemic events from rapid lowering of BP, but the impact of as-needed BP medication use in this population is unknown.

Objective: To assess the risks of acute kidney injury (AKI) and other outcomes from as-needed BP medication administration in a hospitalized veteran cohort.

Design, setting, and participants: This retrospective cohort study using target trial emulation and propensity score matching included adult veterans, who were hospitalized 3 or more days in Veterans Administration hospitals between October 1, 2015, and September 30, 2020. Participants must have been hospitalized on a non-intensive care unit medical or surgical floor, must not have undergone surgery, and must have received at least 1 scheduled BP medication in the first 24 hours of admission. Participants also must have had at least 1 systolic BP more than 140 mm Hg during hospitalization. Data in this study were analyzed from April 2023 to August 2024.

Main outcomes and measures: The primary outcome was time to first AKI occurrence during hospitalization. Secondary outcomes included greater than 25% reduction in systolic BP within 3 hours of as-needed BP medication administration and the composite outcome of myocardial infarction, stroke, or death during hospitalization.

Results: Of the 133 760 veterans eligible for analysis (mean [SD] age, 71.2 [11.6] years), 96% were male. The mean (SD) baseline estimated glomerular filtration rate was 75.7 (22.7) mL/min/1.73m2. A total of 28 526 patients (21%) received as-needed BP medication. As-needed BP medication use was associated with an increased AKI risk (adjusted hazard ratio, 1.23 [95% CI, 1.18-1.29]) compared to nonusers. Subgroup analyses showed higher AKI risk with intravenous as-needed BP medication use (compared to oral or combined oral and intravenous routes). Secondary analyses indicated as-needed BP medication users had a 1.5-fold greater risk of rapid BP reduction (95% CI, 1.39-1.62) and 1.69-fold higher rate of the composite outcome (95% CI, 1.49-1.92) compared to nonusers.

Conclusions and relevance: The results of this retrospective cohort study showed that as-needed BP medication use among veterans is associated with increased AKI risk. The risks and benefits of this type of BP medication use would best be determined through a prospective trial, and these data suggest that there is the necessary equipoise to conduct such a trial.