Predictors of response to SARS-CoV-2 vaccines among maintenance dialysis patients

Background: Vaccines against SARS-CoV-2 are highly effective in the general population;however, their efficacy may be diminished in maintenance dialysis patients, a population particularly vulnerable to COVID-19. We assessed vaccine response in a national sample of maintenance dialysis patients. Methods: Using retrospective clinical data, we assessed seroresponse to vaccine among maintenance dialysis patients cared for at 130 Dialysis Clinic, Inc (DCI) facilities. Via a clinical protocol available to early vaccinating facilities, antibodies against SARSCoV-2 spike antigen were semi-quantitatively assessed beginning with the monthly blood draw at least two weeks after completion of a SARS-CoV-2 vaccine series. Vaccine response was defined as a titer ≥2 U/L, and logistic regression analysis was used to identify characteristics associated with response. Patients with history of COVID-19 prior to antibody assessment were excluded. Results: Among 1,352 patients, 996 (74%) had a serologic response. Serologic response differed significantly by vaccine type: 314/386 (81%) among BNT162b2/ Pfizer recipients, 615/655 (94%) among mRNA-1273/Moderna recipients, and 67/311 (22%) among Ad26.COV2.S/Janssen recipients. Age greater than 75, lack of hepatitis B immunity, immune-modulating medication, lower serum albumin, and COPD were associated with vaccine non-response (Figure). Conclusions: Serologic response to mRNA vaccines is robust among chronic dialysis patients, and the use of mRNA vaccines should be promoted aggressively in this vulnerable population. High rates of non-response to the Janssen vaccine warrant further study. Future research should evaluate the potential role for boosters and whether seroresponse corresponds with protection from COVID-19.