Background: Patients with mild-to-moderate essential hypertension in the HOMED-BP trial were randomly allocated to first-line treatment with a calcium channel blocker (CCB), angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB).
Methods: We recruited 265 (93 for CCB, 71 for ACEI and 101 for ARB) patients who completed the genomic study. Home blood pressure was measured for 5 days off-treatment before randomization and for 5 days after 2-4 weeks of randomized drug treatment. Genotyping was performed by 500K DNA microarray chips. The blood pressure responses to the three drugs were analyzed separately as a quantitative trait. For replication of SNPs with p < 10(-4), we used the multicenter GEANE study, in which patients were randomized to valsartan or amlodipine.
Results: SNPs in PICALM, TANC2, NUMA1 and APCDD1 were found to be associated with CCB responses and those in ABCC9 and YIPF1 were found to be associated with ARB response with replication.
Conclusion: Our approach, the first based on high-fidelity phenotyping by home blood pressure measurement, might be a step in moving towards the personalized treatment of hypertension.