Propranolol for small abdominal aortic aneurysms: results of a randomized trial.

Abstract

Animal and human studies have suggested that beta-blockade may decrease the growth rate of aneurysms. We investigated whether propranolol decreases the growth rate of small abdominal aortic aneurysms (AAAs). We randomly assigned patients with an asymptomatic AAA between 3.0 and 5.0 cm to receive either a placebo (n = 272) or propranolol (n = 276) in a double-blind fashion. Patients were observed for a mean of 2.5 years. The primary end point was the mean annual growth rate as determined by means of ultrasound scanning performed every 6 months. Secondary outcomes were death, surgery, withdrawal from study medication, and quality of life measured by means of the Short-form Health Survey (SF-36). The main analyses were performed by means of intention to treat. The two groups were similar at baseline: 84% were men with a mean age of 69 years and a mean AAA size of 3.8 cm. Fewer patients in the placebo group stopped their study medication (26.8% vs 42.4%; P =.0002). The annual growth rate was similar in the two groups (placebo, 0.26 cm/y vs propranolol 0.22 cm/y; P =.11). There was a trend toward more elective surgery in the placebo group (26.5% vs 20.3%; P =.11), but there was no difference in death rate (placebo, 9% vs propranolol, 12%; P =.36). Patients in the propranolol group had significantly poorer quality of life scores in the physical functioning, physical role, and vitality dimensions of the SF-36. Patients with AAAs do not tolerate propranolol well, and the drug did not significantly affect the growth rate of small AAAs.