NEW YORK (Reuters Health) – Giving beta-blockers to patients with cocaine-associated chest pain appears to be safe and may even save lives, according to research in the May 24 Archives of Internal Medicine.

In this retrospective study, beta-blockers given in the emergency department (ED) significantly reduced systolic blood pressure, while discharge on beta-blockers reduced cardiovascular mortality by 71%.

Professional guidelines advise against use of beta-blockers in this population, based on the belief that they may worsen the toxic cardiovascular effects of cocaine. But these recommendations are based on “animal studies, small human experiments, and anecdote,” say senior author Dr. Gregory M. Marcus, from the University of California, San Francisco, and his associates.

Their data are from 328 patients admitted to the San Francisco General Hospital between 2001 and 2006 with chest pain and urine toxicology positive for cocaine. Nearly half the patients (46%) received a beta-blocker in the emergency department (ED), while 65% received one at some point during their hospitalization.

After adjusting for other antihypertensive drugs given at the same time, patients treated with beta-blockers in the ED had a mean 8.6-mm Hg greater decrease in systolic BP than those who received one later in their hospital stay (p = 0.006).

“The important finding,” the authors say, “is that the addition of beta-blockers did not cause a rise in BP as might be expected in the event of true unopposed alpha-receptor stimulation.”

Other than that, the authors report no significant differences between those who did and did not receive a beta-blocker in the ED, in terms of electrocardiogram changes, peak troponin levels, or hospital length of stay. They also saw no significant differences in catastrophic events (i.e., need for intubation or vasopressors, development of ventricular arrhythmia, or death).

During a mean follow-up of slightly more than two and a half years, 45 patients (14%) died, including 14 (12%) of those who were discharged on a beta-blocker regimen and 29 (15%) who were not.

Discharge on a beta-blocker regimen was associated with a significant 71% reduction in the risk of cardiovascular death (HR 0.29, p = 0.047), and a trend toward lower risk of death (HR 0.53, p = 0.08), after adjusting for potential confounders.

The authors note that this was an observational study with the attendant limitations, and that they were unable to assess behaviors and treatments after hospital discharge.

Reference:
Arch Intern Med 2010;170:874-879.