Pharmacogenetics of antihypertensive treatment

Hypertension is a common disorder associated with increased cardiovascular morbidity and mortality. Unfortunately, in the United States, only about one third of those who are aware of their hypertensive status successfully control their blood pressure. One reason for this is the variable and unpredictable response individuals have to pharmacologic treatment. Clinicians often resort to a trial-and-error approach to match patients with effective drug treatment. It is the goal of hypertension pharmacogenetics to apply knowledge of genetic predictors of treatment response to drugs that lower blood pressure and to translate this knowledge into clinical practice. To date, more than 30 studies have investigated associations between specific genetic polymorphisms and response to particular antihypertensive drugs. Angiotensin-converting enzyme inhibitors have been most frequently studied, followed by diuretics, beta-blockers, angiotensin II blockers, adrenergic alpha-agonists, and calcium channel blockers. Renin-angiotensin-aldosterone system genes have been the most widely studied, with the angiotensin-converting enzyme I/D variant being typed in about one third of all hypertension pharmacogenetic studies to date. In a number of cases, significant and potentially promising associations between genes and drug treatments have been reported. However, taken in sum, the literature suggests that the path from gene drug-outcome association studies to clinically useful knowledge may be neither short nor direct. In the future, carefully designed studies must acknowledge that hypertension is caused by multiple genes and environmental factors that act in concert. These considerations, along with a better understanding of the complexities of the biology of hypertension, open the next set of opportunities for hypertension pharmacogenetics research.