Cytochrome P450 2J2*7 Single-nucleotide Polymorphism and Nocturnal Hypertension in an Elderly Turkish Population

Objective: Blood pressure shows a physiological diurnal rhythm. Altered blood pressure circadian rhythm is more common in the elderly. Nocturnal hypertension (NH) and/or impaired nocturnal dipping profile are associated with increased mortality risk. The CYP2J2*7 polymorphism is associated with decreased arachidonic acid metabolite levels and increased cardiovascular mortality risk in different populations. The aim of this study was to investigate whether NH was associated with the CYP2J2*7 polymorphism in an elderly Turkish population. Methods: Ambulatory blood pressure data were obtained from 120 elderly (78 women and 42 men, aged 60-105 years) volunteers during 24 h. The CYP2J2*7 (G/T) polymorphism was evaluated using a Taqman® Drug Metabolism Genotyping Assay kit and a TAQMAN ABI7900 device. Results: The CYP2J2*7 T-allele frequency was 6.7% in our study population. The 24 h, day, and night systolic blood pressures were found to be 2-5 mmHg higher in CYP2J2*7T-carriers (n=15) than in individuals with the GG genotype (n=105), however, the differences between the genotype groups were not statistically significant. The systolic blood pressure morning increase slope values of the CYP2J2*7 carriers and GG genotype group were 8.6±2.0 (mean ± standard error of mean) and 5.7±0.5, respectively, i.e., 50.7% higher in T-carriers (p=0.039). There was no statistically significant difference in the frequency of NH with the CYP2J2*7 polymorphism. Conclusion: Considering the existing literature with our findings, the CYP2J2*7 carrier status may indicate an increased risk of cardiovascular events. However, further studies are required to verify the significance of this finding.