Objective: To determine to what extent participants in randomized controlled hypertension trials (RCTs) could be compared to patients with hypertension in general practices.
Study design and setting: We analyzed RCTs that had been used in hypertension guidelines or were available for future hypertension guidelines. The characteristics of the participants of these RCTs were compared with those of the patients with hypertension in general practices. In addition, inclusion and exclusion criteria of the RCTs were applied to the hypertension patients in the general practices.
Results: Twenty-one trials were analyzed. Participants' characteristics often differed from those of the patients with hypertension in general practices, in particular in the older trials where the participants showed lower cardiovascular risk. More recent trials showed participants' profiles that better reflected those of the patients under treatment in a general practice. Less than half of the patients undergoing treatment in a general practice would have been included in the hypertension trials.
Conclusion: Participants taking part in trials differed from patients with hypertension in a general practice in a number of important aspects. This hampers their external validity. Inclusion of participants with comorbidity and other general practice characteristics would improve translation of study findings to daily practice recommendations.