The correlation of shift work and CLOCK, BMAL1, and PER1 gene polymorphisms with hypertension in healthcare workers: A cross-sectional study

Abstract

This study aimed to investigate the polymorphisms of circadian clock genes and the association of shift work and gene polymorphisms with hypertension in healthcare workers. This study recruited 222 healthcare workers, of whom 76 had primary hypertension (Hyp group) and 146 served as controls (Control group). General information and working hours were collected through questionnaires. Next, the identification of specific single nucleotide polymorphism (SNP) loci related to the Circadian locomotor output cycles kaput (CLOCK), brain and muscle arnt-like 1 (BMAL1), and PER1 genes was conducted by literature and PDGene database search. Venous blood samples were then collected for DNA extraction, and polymerase chain reaction-restriction fragment length polymorphism techniques were used to analyze the genotyping and allele frequency of the SNP sites. Finally, multivariate logistic regression was employed to analyze the association between various risk factors and hypertension in healthcare workers. Compared to the control group, the Hyp group had significantly higher proportions of alcohol consumption and family history of hypertension, while the average sleep duration and average exercise time were significantly lower. Shift work analysis showed that the Hyp group had a significantly lower average number of evening shifts per month while a much higher average number of night shifts per month compared to the control group. The GG genotype at the CLOCK rs1801260 locus was associated with a lower risk of hypertension (OR = 0.446), and the TT genotype of the BMAL1 rs11022775 locus also showed a similar protective effect (OR = 0.426). However, the genotype distribution of the PER1 rs2735611 locus was not significantly associated with the risk of hypertension. Multivariate regression analysis revealed that a family history of hypertension and insufficient sleep were significantly associated with the risk of hypertension, and the average number of night shifts per month was positively correlated with the risk of hypertension. Specific polymorphisms in the CLOCK and BMAL1 genes may have a protective effect against hypertension in healthcare workers, while polymorphisms in the PER1 gene are not significantly associated with the risk of hypertension. Additionally, a family history of hypertension, insufficient sleep, and shift work patterns may be significant risk factors for hypertension.