Hypertension guidelines, meta-analyses and clinical trials: do we assume too much?

Given fundamental differences in the recommendations in guidelines from major national and international committees, we cannot rely on them unquestioningly. Different antihypertensive agents are known to have differing effects according to age and race. Exchanging (rather than following guideline recommendations of adding to) an ineffective first-line antihypertensive drug can result in control of hypertension with monotherapy. Conclusions about a preferable first-line antihypertensive agent are limited by trial protocols with varying drug doses and questionable drug combinations. Guidelines are often based on meta-analyses of drugs of a particular class, which could ignore important differences between drugs within a class. Trials of 3-5 years cannot determine the long-term effects of drugs which patients often take for decades.