Beta-blockers and migraine. Efficacy of time-release propranolol versus placebo

The efficacy and safety of long-acting propranolol (LA.P) 160 mg once-daily in the prophylactic treatment of migraine were tested against placebo in a multicentric, double-blind, randomized study comparing the two groups in a parallel manner over a treatment period of 12 weeks, and following a 4 week-placebo run-in period. Fifty-five out of the 74 patients who entered the trial included at the end of the run-in period. Forty-one patients completed the study. Out of the 14 patients who withdrew from the study, none discontinued because of side-effects. The statistical analysis was done according to the "intention to treat" principle. LA.P was significantly more efficient than placebo in reducing the frequency of migraine attacks (p = 0.01 by variance analysis). LA.P reduced the average number of monthly crises by 48% on day 84. There was a slight but significant reduction of the systolic blood pressure and heart rate in the erect position. There was no significant difference between LA.P and placebo regarding either the number of complaints or the number of side-effects elicited out of an 17 item questionnaire. None of the observed side effects led to a withdrawal of treatment.