Personalized antihypertensive treatment guided by pharmacogenomics in China

The implementation of genotyping for anti-hypertensive drugs in clinical practice remains a challenge. We conducted this study to analyze the distribution of polymorphisms of antihypertensive drug-related genes in Changsha County in China and compare the clinical effectiveness of genotype-guided and clinical experience-guided antihypertensive therapy in hypertensive individuals.

A total of 9,933 essential hypertensive participants from Changsha County were consecutively enrolled in our study, and 7 genetic polymorphic loci (CYP2D6*10, ADRB1, CYP2C9*3, AGTR1, ACE, CYP3A5*3 and NPPA) were detected by a polymerase chain reaction (PCR)-fluorescence probe. From an available sample of 660 hypertensive participants, 495 cases were randomly identified by genotype-guided therapy and 165 cases by clinical experience-guided therapy. We performed 24-hour ambulatory blood pressure (BP) monitoring on each of these cases, pre- and post-intervention.

In the enrolled 9,933 cases, the mutation frequencies of CYP2C9*3, ADRB1(1165G>C), AGTR1(1166A>C), CYP2D6*10, ACE(I/D), CYP3A5*3 and NPPA(2238T>C) were 4.41%, 74.60%, 5.55%, 57.08%, 30.94%, 69.03% and 1.19%, respectively. In both genotype-guided and clinical experience-guided groups, the comparisons of intra-group pre-and post-treatments showed significant decreases in diastolic blood pressure (DBP) (P<0.01) and significant increases in the control rate of BP (47.1% vs. 38.6% and 37.5% vs. 33.9%, P<0.05) in response to adjusted antihypertensive agents. Correspondingly, the extent of the reduction of systolic blood pressure (SBP; 3.52±11.72 vs. 0.92±9.14 mmHg), the extent of the increase in the rate of BP control (8.5% vs. 3.6%) and the percentage rate of decrease of grades 2 and 3 hypertensive individuals were more significant in the genotype-guided group than that in the clinical experience-guided group (P<0.01).

While prescribing anti-hypertensive drugs, appropriate dosage and type adjustments should be made according to the gene mutation frequency and individual circumstances. Pharmacogenomics-guided personalized treatment of hypertensive patients is likely to be a more effective strategy, especially in those with significantly elevated SBP.