EBM based approach to angiotensin II receptor evaluation and management.

Background: National drugs reports demonstrate increasing consumption of Angiotensin II Receptor antagonist (+ 17%); Trend of cost: +8,3% for Losartan; +42% for Valsartan; +11,3% for Irbesartan. Methods: We evaluated almost 200 studies, by searching Pub-Med, OVID, Embase. First, 103 studies were excluded because of lack of randomization and control; then 28 studies were excluded because of combination therapy. We included 25 studies in a systematic review. Results: We identify as clinical effectiveness outcome the decrease in mean systolic and diastolic pressure after 8 weeks of therapy. We found 4 comparable studies to this outcome; lack of standard error of mean or CI in two studies made impossible to generate pooled estimates of outcome. After funding review, we retrieved 4 studies with no explicit Drug’s Companies support: one of them favours valsartan versus olmesartan in 115 randomized patients; one other favours valsartan versus amlodipine in elderly patients,one other reports equivalence between irbesartan and valsartan, the last one favours olmesartan versus losartan and valsartan, without SE of means. Either in all studies, either in the independent ones outcome was substantial equivalence in the antihypertensive effects of the Angiotensin II Receptor antagonist. Conclusions: Angiotensin II Receptor antagonist are emerging therapeutic alternatives; however to generate consistent evidence is crucial to implement best practice and effective therapeutic choices. To design an independent big trial is a difficult challenge in the actual research environment, a smart observational study could constitute an effective alternative.