Does native vitamin D, or active vitamin D modulate the neutralising antibody responses to COVID-19 vaccination in haemodialysis patients?

Introduction: Several studies have reported that patients with low levels of Vitamin D₃ have impaired responses to vaccination, including COVID-19 vaccines, so we reviewed the response to COVID-19 vaccination in haemodialysis patients, who typically have reduced Vitamin D₃ levels.

Methods: The inhibitory antibody (IC50) responses to several COVID-19 variants following vaccination in a cohort of United Kingdom haemodialysis patients receiving two vaccinations between March 2021 and May 2021 were reviewed.

Results: A total of 183 haemodialysis patients, 65.5% male, mean age 65.6 ± 14.1 years, 46.4% diabetic, 42.1% white ethnicity, body mass index 26.9 ± 6.5 kg/m² dialysis vintage 36.2 (18.3-69.3) months were studied. Following the first vaccination, the median IgG microneutralisation IC50 response was undetectable for all variants (wild-type, alpha, beta and delta). Follow-up after the second vaccination showed that the microneutralisation response to all variants increased and was greater for the wild-type variant compared to alpha, beta and delta, all p < 0.001, There were no differences comparing the IC50 responses according to 25-Vitamin D₃ levels, and the prescription of activated Vitamin D. Although patients who had previously tested positive for COVID-19 prescribed higher doses of alfacalcidol had higher seroprotection responses to the alpha (χ² = 15, p = 0.002) and beta variants. (χ² = 13, p = 0.005).

Conclusions: The response to COVID-19 vaccination was reduced in our elderly haemodialysis patients compared to younger less frail patients, however there was no overall demonstrable effect of either 25-Vitamin D₃ levels or the prescription of activated forms of Vitamin D on the immune response following vaccination against COVID-19, unless patients had previously tested positive for COVID-19.