HealthDay News — The risk for having positive COVID-19 test results is 2.64-fold greater for Black individuals with a vitamin D level of 30 to 39.9 ng/mL versus a level of ≥40 ng/mL, according to a study published online March 19 in JAMA Network Open.
David O. Meltzer, M.D., Ph.D., from University of Chicago, and colleagues examined whether COVID-19 test results are associated with differences in vitamin D levels ≥30 ng/mL. The analysis included 4,638 individuals (mean age, 52.8 years; 69 percent women) who had data for a vitamin D level available within one year of COVID-19 testing.
The researchers found that lower vitamin D levels (<20 ng/mL) were more common in Black individuals than White individuals. Among White individuals, a positive COVID-19 test result was not significantly associated with vitamin D levels. However, there was such an association among Black individuals (for <20 ng/mL: incidence rate ratio [IRR], 2.55 [95 percent confidence interval (CI), 1.26 to 5.15; P = 0.009]; 20 to <30 ng/mL: IRR, 1.69 [95 percent CI, 0.75 to 3.84; P = 0.21]; 30 to <40 ng/mL: IRR, 2.64 [95 percent CI, 1.24 to 5.66; P = 0.01]). Estimated COVID-19 positivity rates in Black individuals were 9.72 percent for those with a vitamin D level <20 ng/mL, 6.47 percent for individuals with a vitamin D level of 20 to <30 ng/mL, 10.10 percent for individuals with a vitamin D level of 30 to <40 ng/mL, and 3.82 percent for individuals with a vitamin D level of ≥40 ng/mL.
“Because such levels exceed levels recommended for other reasons, individual and policy decisions about higher supplement dosing and vitamin D testing to achieve such levels should be even more carefully considered than dosing to avoid vitamin D deficiency as currently defined,” the authors write.