Of those on treatment for high blood pressure, the most common agents used were diuretics in 63.5%, followed by blockers of the renin-angiotensin system (RAS) in 61.3% (either angiotensin converting enzyme inhibitors or angiotensin receptor blockers), calcium antagonists (31.6%), β-blockers (19%), and centrally acting sympatholytics (4.5%). This evidence concerns the gene REN and hypertensive disorder.