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Examination of the Moderating Effect of Race on the Relationship between Vitamin D Status and COVID-19 Test
Ian Crandell1, Michelle Rockwell2,3, Phyllis Whitehead4,5
1Center for Biostatistics and Health Data Sciences, Virginia Polytechnic Institute and State University, Roanoke, Virginia, USA.
Introduction:
With a well-established role in inflammation and immune function, vitamin D status has emerged as a potential factor for coronavirus disease-2019 (COVID-19).
Objective:
The purpose of this study was to evaluate the moderating effect of race on the relationship between vitamin D status and the risk of COVID-19 test positivity, and to compare propensity score (PS) model results to those obtained from classical bivariate and multivariable models, which have primarily comprised the literature to date.
Methods:
Electronic health record (EHR) data from TriNetX (unmatched n = 21,629; matched n = 16,602) were used to investigate the effect of vitamin D status, as measured by 25-hydroxyvitamin D [25(OH)D], on the odds of experiencing a positive COVID-19 test using multivariable logistic regression models with and without PS methodology.
Results:
Having normal (≥ 30 ng/mL) versus inadequate 25(OH)D (< 30 ng/mL) was not associated with COVID-19 positivity overall (OR = 0.913, p = 0.18), in White individuals (OR = 0.920, p = 0.31), or in Black individuals (OR = 1.006, p = 0.96). When 25(OH)D was analyzed on a continuum, a 10 ng/mL increase in 25(OH)D lowered the odds of having a positive COVID-19 test overall (OR = 0.949, p = 0.003) and among White (OR = 0.935, p = 0.003), but not Black individuals (OR = 0.994, p = 0.75).
Conclusions:
Models which use weighting and matching methods resulted in smaller estimated effect sizes than models which do not use weighting or matching. These findings suggest a minimal protective effect of vitamin D status on COVID-19 test positivity in White individuals and no protective effect in Black individuals.
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