The innate immune system is activated by vitamin D, and a lack of it makes people more vulnerable to respiratory infections and sicker, including COVID-19. For a study, researchers sought to determine the relationship between vitamin D status and drugs and COVID-19 infection, as well as illness severity measured by hospitalization and dialysis patient death.

Between March 2020 and May 2021, they examined the blood vitamin D levels, cholecalciferol and alfacalcidol prescriptions, and accompanying medical records of adult dialysis patients from a tertiary center in the United Kingdom. The polymerase chain reaction (PCR) results were used to determine COVID-19 infection.

Of the 1,035 dialysis patients, 362 (35%) had COVID-19 PCR results that were positive. Despite higher cholecalciferol prescriptions (median 20,000 (20,000-20,000) versus 20,000 (0-20,000) IU/week, P< .001) and lower alfacalcidol prescriptions (0 (0-3.0) versus 2.0 (0.-5.0) ug/week, P< .001), COVID-19 positive patients had lower native median vitamin D levels (65 (39-95) versus 74 (40.5-101) n On multivariate logistic regression, COVID-19 infection was adversely correlated with alfacalcidol (P< .001), cholecalciferol dosage, and hemodialysis versus peritoneal dialysis (P< .001). Although those who passed away were given lower alfacalcidol dosages, blood vitamin D levels and alfacalcidol dosages were not substantially different between patients who needed hospitalization and those who were handled at home.

Patients on dialysis who developed COVID-19 had lower levels of natural vitamin D before COVID-19 and were given lower alfacalcidol prescriptions. However, there was no link between vitamin D level and the severity of the illness. The retrospective observational investigation supported the idea that vitamin D may have a role in dialysis patients’ vulnerability to COVID-19 infection.