vitamin d deficiency and receptor polymorphisms as risk factors for covid-19

Background: early immune responses to covid-19 can help eliminate the virus; therefore, strategies to improve the immune system have become important in disease prevention. vitamin d plays a crucial role in the immune response to sars-cov-2 by increasing the expression of the vitamin d receptor. objectives: this study investigated the impact of vitamin d deficiency, fok 1, and taq 1 vitamin d receptor (vdr) gene polymorphisms and comorbidities on the susceptibility to covid-19. methods: fok1 and taq1 polymorphisms were analyzed using the rt-pcr method, and vitamin d levels were measured using the chemiluminescence method. a total of 200 patients, 100 with covid-19 and 100 without, provided blood samples for analysis. results: the covid-19 positive group had a significantly lower mean vitamin d level of 16.2 ± 11.3 ng/ml compared to the covid-19 negative control group, 26.7 ± 15.9 ng/ml (p < 0.001). individuals with a vitamin d level below 18.4 ng/ml had a 2.448 times higher risk of covid-19 positivity (p < 0.001). there was no significant difference in the fok1 and taq1 gene polymorphisms between the two groups. (p = 0.548 and p = 0.098). the covid-19 positive group had a significantly higher number of comorbid diseases with 40 (40%) compared to the negative group with 10 (10%) participants (p < 0.001). conclusions: levels of vitamin d above the cut-off value of 18.4 ng/ml were found to protect against covid-19, while the presence of comorbid diseases was identified as a risk factor. however, no association was observed between the fok1 and taq1 polymorphisms and susceptibility to covid-19.