Pharmacogenetic approaches to hypertension therapy: Design and rationale for the Genetics of Hypertension Associated Treatment (GenHAT) study

The Genetics of Hypertension Associated Treatment (GenHAT) study will determine whether variants in hypertension susceptibility genes interact with antihypertensive medication to modify coronary heart disease (CHD) risk in hypertensives. GenHAT is an ancillary study of the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial, ALLHAT, a double-blind, randomized trial of 42 418 hypertensives, 55 years of age or older, with systolic or diastolic hypertension and one or more risk factors for cardiovascular disease. About 50% are non-white, and about half are female. ALLHAT completes follow-up in March 2002. GenHAT is typing variants in hypertension genes; completion of genotyping is scheduled for 2003. Analysis of gene-treatment interactions in relation to outcomes include CHD, stroke, heart failure, and blood pressure lowering. To our knowledge, GenHAT is the largest pharmacogenetic study ever conducted. An added strength is its ability to link gene-treatment interactions with important clinical outcomes across diverse ethnic and gender groups.