A critical update on the role of mild and serious vitamin D deficiency prevalence and the COVID-19 epidemic in Europe

Abstract

Objectives: Coronavirus disease 2019 (COVID-19) has emerged as a pandemic, affecting nearly 180 million people worldwide as of June 22, 2021. Previous studies have examined the association between the mean vitamin D (Vit D) concentration of each country and COVID-19 infection and mortality rate in European countries. The aim of the present study was to critically evaluate the relationship between prevalence of mild and severe Vit D deficiency in each country and COVID-19 infection, recovery, and mortality using updated data and a different methodological approach.

Methods: Information on Vit D concentration or deficiency for each country was retrieved through a literature search. COVID-19 infections and mortalities per million people and total recoveries, as of June 22, 2021, were obtained. The associations between Vit D deficiency and COVID-19 infection, recovery, and mortality were explored using correlation coefficients and scatterplots.

Results: Non-significant correlations were observed between both number of COVID-19 infections (r = 0.363, P = 0.116) and number of recoveries (r = 0.388, P = 0.091) and the prevalence of mild Vit D deficiency (<50 nmol/L). Similarly, non-significant correlations were observed between both infections (r = 0.215, P = 0.392) and recoveries (r = 0.242, P = 0.332) and the prevalence of severe Vit D deficiency (<30 nmol/L). Significant correlations were found between COVID-19 mortality and prevalence of both mild Vit D deficiency (r = 0.634, P = 0.003) and severe Vit D deficiency (r = 0.538, P = 0.021).

Conclusions: The prevalence of neither mild nor severe Vit D deficiency was associated with the number of COVID-19 infections in European countries. Thus, it is an important parameter to consider when implementing preventive measures to face COVID-19.

Keywords: COVID-19; Deficiency; Europe; Infections; Mortalities; Vitamin D.

Fig. 1

Scatter diagram of the prevalence of vitamin D deficiency (<50 nmol/L) versus COVID-19 infections per million people, as of June 22, 2021 (r = 0.363, P = 0.166). AUT, Austria; BEL, Belgium; BGR, Bulgaria; BIH, Bosnia and Herzegovina; CHE, Switzerland; DEU, Germany; ESP, Spain; FIN, Finland; FRA, France; GBR, United Kingdom; GRC, Greece; HRV, Croatia; IRL, Ireland; ITA, Italy; NOR, Norway; PRT, Portugal; ROU, Romania; RUS, Russia; SVN, Slovenia; UKR, Ukraine.

Fig. 2

Scatter diagram of the prevalence of severe vitamin D deficiency (<30 nmol/L) versus COVID-19 infections per million people, as of June 22, 2021 (r = 0.215, P = 0.392). AUT, Austria; BEL, Belgium; BGR, Bulgaria; BIH, Bosnia and Herzegovina; CHE, Switzerland; DEU, Germany; GBR, United Kingdom; GRC, Greece; HRV, Croatia; FIN, Finland; FRA, France; IRL, Ireland; ITA, Italy; NOR, Norway; PRT, Portugal; ROU, Romania; SVN, Slovenia; UKR, Ukraine.

Fig. 3

Scatter diagram of the prevalence of vitamin D deficiency (<50 nmol/L) versus COVID-19 deaths per million people, as of June 22, 2021 (r = 0.634, P = 0.003). AUT, Austria; BEL, Belgium; BGR, Bulgaria; BIH, Bosnia and Herzegovina; CHE, Switzerland; DEU, Germany; ESP, Spain; FIN, Finland; FRA, France; GBR, United Kingdom; GRC, Greece; HRV, Croatia; IRL, Ireland; ITA, Italy; NOR, Norway; PRT, Portugal; ROU, Romania; RUS, Russia; SVN, Slovenia; UKR, Ukraine.

Fig. 4

Scatter diagram of the prevalence of severe vitamin D deficiency (<30 nmol/L) versus COVID-19 deaths per million people, as of June 22, 2021 (r = 0.538, P = 0.021). AUT, Austria; BEL, Belgium; BGR, Bulgaria; BIH, Bosnia and Herzegovina; CHE, Switzerland; DEU, Germany; FIN, Finland; FRA, France; GBR, United Kingdom; GRC, Greece; HRV, Croatia; IRL, Ireland; ITA, Italy; NOR, Norway; PRT, Portugal; ROU, Romania; SVN, Slovenia; UKR, Ukraine.