Vitamin D Threshold below which COVID-19 Morbidity, Mortality, and Lethality May Increase
Ernest Emilion*1, Richard Emilion2
1Community Clinic, 3 rue du Pressoir, Paris 75020, France
2Denis Poisson Institute, University of Orléans
*Corresponding Author: Dr. Ernest Emilion, 3 rue du Pressoir, Paris 75020, France. Tel:+33 7 52 17 40 14, Email: firstname.lastname@example.org
Received date: 10 April, 2022 Accepted date: 13 May,, 2021 Published Date: 16 May,, 2021
Citation: Emilion E, Emilion R(2022) Vitamin D Threshold below which COVID-19 Morbidity, Mortality, and Lethality May Increase. Sci J Health Sci Res Vol: 1, Issu: 2 (65-73).
Copyright: © 2022 Emilion E, et al.
Vitamin D is a well-known natural immune modulator and its status is defined by the levels of serum 25-hydroxyvitamin D (25(OH)D) in the serum. Negative correlations were recently observed between mean levels of 25(OH)D per one million inhabitants of a country, and COVID-19 morbidity and mortality rates. The aim of this study was to estimate the threshold of 25(OH)D below which COVID-19 morbidity, mortality, and lethality rates, may significantly increase. A data table found in the literature, containing a list of twenty European countries and their corresponding mean 25(OH)D was updated with COVID-19 rates computed in 2020, 2021, and 2022. We first found that these rates were the highest in the range (50 ± 10) nmol/L, that is, mainly in the range of vitamin D deficiency. Then, using a kernel regression we found significant increases below 25(OH)D levels of (60 ± 10) nmol/L, that is, mainly in the range of vitamin D insufficiency. It should be emphasized that the results in 2020, 2021 and 2022 were quite similar. To our knowledge, there is no similar study estimating such thresholds. Our estimations suggested that 25(OH)D levels should attain at least (60 ± 10) nmol/L and COVID-19 prevention strategies for European countries should include, in part, vitamin D supplementation in order to maintain 25(OH)D levels above the range of vitamin D insufficiency. Similar studies are needed in other latitudes and other population groups.
Keywords: COVID-19, Vitamin D, 25(OH)D, PTH, Thresholds, Regression.