A randomized, double-blind, placebo-controlled crossover candesartan trial «Tronvik E, Stovner LJ, Helde G et al. Prophylactic treatment of migraine with an angiotensin II receptor blocker: a randomized controlled trial. JAMA 2003;289(1):65-9. »1 included a total of 60 subjects with migraine. A placebo run-in period of 4 weeks was followed by two 12-week treatment periods separated by 4 weeks of placebo washout. Thirty patients received 16 mg candesartan daily in the first treatment period followed by placebo in the second period. The remaining 30 received placebo followed by candesartan. In a period of 12 weeks, the mean number of headache days (the primary end point) was 13.6 with candesartan vs. 18.5 with placebo (p=0.001). Secondary end points also favored candesartan, including hours with headache (139 vs 95; p<0.001), days with migraine (12.6 vs 9.0; p<0.001), hours with migraine (92.2 vs 59.4; p<0.001), headache severity index (293 vs 191; p<0.001), level of disability (20.6 vs 14.1; p<0.001) and days of sick leave (3.9 vs 1.4; p=0.01). The number of candesartan responders (reduction of ≥50% compared with placebo) was 18 (31.6%) of 57 for days with headache and 23 (40.4%) of 57 for days with migraine. Adverse events were similar in the 2 periods.
In another randomized, double-blind study «Diener HC, Gendolla A, Feuersenger A et al. Telmisartan in migraine prophylaxis: a randomized, placebo-controlled trial. Cephalalgia 2009;29(9):921-7. »2 a total of 95 migraine patients were randomized to telmisartan 80 mg or placebo. The primary end-point was the reduction in the number of migraine days between the 4-week baseline period and the last 4 weeks of the 12-week treatment period. A responder indicated a symptom reduction of ≥50% in these periods. The reduction in migraine days was 1.65 with telmisartan and 1.14 with placebo (p>0.05). Post hoc analyses adjusting for baseline and centre showed a 38% reduction in migraine days with telmisartan vs. 15% with placebo (p=0.03), and a borderline significant difference in responders (40% vs. 25%, p=0.07). The incidence of adverse events was similar between treatments.
Comment: The quality of evidence is downgraded by imprecise results (only few small trials reported).