Before ALLHAT, alpha-blockers were considered first-line drugs, so maybe prescribers are just “sticking with something they know and are familiar with,” he said.
To assess the risks of continued use, the investigators used propensity scoring to match 69,092 patients prescribed alpha-blockers to 69,092 who were prescribed other antihypertensives, based on age, comorbidities, date of treatment, and a slew of other potential confounders. Patients were considered to be on an alpha-blocker only when they were filling prescriptions for the drugs. If they were not filling prescriptions they flipped into the unexposed arm.
The incident rates of ED visits and hospitalizations for hypotension and related complications – syncope, falls, and fractures – were markedly higher among alpha-blocker users. After adjusting for the total number of antihypertensives patients were on, those on alpha-blockers were 34% more likely to go to the ED or be hospitalized for hypotension, 49% more likely for syncope, 27% more likely for falls, and 41% more likely for fractures. First-dose effects don’t explain the findings; patients were often on alpha-blockers for years beforehand.
Alpha-blocker patients were also 26% more likely to have a major cardiovascular event, including heart failure and MI. The risks were greatest in those older than age 85 years. The results were all statistically significant.