Association of susceptibility to postoperative pulmonary infection and prognosis with polymorphisms of vitamin D receptor gene in severe valve heart disease patients

OBJECTIVE To explore the association of susceptibility to postoperative pulmonary infection and prognosis with polymorphisms of vitamin D receptor (VDR) gene in patients with severe valve heart disease patients. METHODS A total of 82 patients with severe valve heart disease who underwent valve replacement in the First Affiliated Hospital of Nanyang Medical College from May 2018 to May 2021 were assigned as the study group, meanwhile, 36 patients who underwent valve replacement but were not complicated with pulmonary infection were chosen as the control group. The patients of the study group were divided into the survival group with 69 cases and the death group with 13 cases according to the postoperative survival status during hospital stay. The clinical data were collected from all of the patients, the peripheral venous blood specimens were collected, and the gene polymorphisms at Fok1, TaqI and BsmI loci of the VDR gene were detected by polymerase chain reaction-restriction-fragment-length polymorphism (PCR-RFLP) assay. RESULTS Totally 89 strains of pathogens were isolated from the 82 patients complicated with pulmonary infection, among which gram-negative bacteria (75.28%, 67/89) were dominant. There were significant differences in the frequencies of Fokl genotypes(TT/TC/CC) and alleles (T, C) of VDR gene between the study group and the control group (P<0.05). There were no significant differences in the frequencies of TaqI genotypes(CC/CT/TT) , alleles(C, T), BsmI genotypes (GG/GA/AA) and alleles (G, A) between the study group and the control group. Among the 82 patients who were complicated with postoperative pulmonary infection, there were no significant differences in the frequencies of Fokl, TaqI, BsmI genotypes and alleles of VDR gene between the survival group and the death group. CONCLUSION The Fok1 gene polymorphism of VDR gene is closely associated with the susceptibility to the postoperative pulmonary infection in the patients with severe valve heart disease, and the C allele may increase the risk of postoperative pulmonary infection. The gene polymorphisms at Fok1, TaqI and BsmI loci of VDR gene did not show remarkable association with the clinical treatment outcomes.