Vitamin D supplementation and clinical outcomes in COVID-19: a systematic review and meta-analysis

Abstract

Purpose To provide a precise summary and collate the hitherto available clinical evidence on the effect of vitamin D supplementation on clinical outcomes in COVID-19 patients. Methods PubMed/MEDLINE, Scopus, and Web of Science databases were systematically searched using appropriate keywords till June 8, 2021, to identify observational studies and randomized controlled trials (RCTs) reporting adverse clinical outcomes (ICU admission and/or mortality) in COVID-19 patients receiving vitamin D supplementation vs. those not receiving the same. Both prior use and use of vitamin D after COVID-19 diagnosis were considered. Unadjusted/adjusted pooled odds ratio (OR) with 95% confidence intervals (CI) were calculated (PROSPERO registration number CRD42021248488). Results We identified 13 studies (10 observational, 3 RCTs) pooling data retrieved from 2933 COVID-19 patients. Pooled analysis of unadjusted data showed that vitamin D use in COVID-19 was significantly associated with reduced ICU admission/mortality (OR 0.41, 95% CI: 0.20, 0.81, p = 0.01, I 2 = 66%, random-effects model). Similarly, on pooling adjusted risk estimates, vitamin D was also found to reduce the risk of adverse outcomes (pooled OR 0.27, 95% CI: 0.08, 0.91, p = 0.03, I 2 = 80%, random-effects model). Subgroup analysis showed that vitamin D supplementation was associated with improved clinical outcomes only in patients receiving the drug post-COVID-19 diagnosis and not in those who had received vitamin D before diagnosis. Conclusions Vitamin D supplementation might be associated with improved clinical outcomes, especially when administered after the diagnosis of COVID-19. However, issues regarding the appropriate dose, duration, and mode of administration of vitamin D remain unanswered and need further research.

The Perception of Vitamins and Their Prevalence in Fortified Food and Supplements in Japan

“…Among vitamins, the role of vitamin D in COVID-19 is well researched, because vitamin D plays a role in the maintenance of the immune system and upper respiratory infections [27]. Lower plasma vitamin D levels are associated with the risk of COVID-19 infection and aggravation [28,29] and supplementation with vitamin D in COVID-19 patients was significantly associated with reduced ICU admission/mortality [30].…”

Vitamins and other immune-supportive elements as cofactors for passing the COVID-19 pandemic

“…The action of vitamin D on innate immunity is related to increased expression of defensins, human cathelicidin, and LL-37 that are antimicrobial peptides acting against the invasion of microorganisms [74,75]. These natural internal peptides cause an upsetting of the infecting microbes membranes, and also, they could act differently through reducing microorganism endotoxins activity [76].…”

El rol de la suplementación con vitamina D en la infección por COVID-19

“…Utilizamos el filtro de revisión sistemática, lo que redujo los registros obtenidos a 27 resultados, de los cuales 15 constituyeron revisiones sistemáticas que sintetizan evidencia sobre la relación entre los niveles séricos de vitamina D y la incidencia y/o la severidad de COVID-19 o sobre la eficacia de la suplementación con esta vitamina para el tratamiento de esta enfermedad. Entre estas últimas, seleccionamos cuatro por considerarlas la evidencia más pertinente para responder a la pregunta de la paciente y ayudar a la toma de decisiones en el consultorio de atención primaria [1][2][3][4][5] .…”

“…En esta investigación se analizaron los resultados de cuatro revisiones sistemáticas, una de ellas sobre la suplementación con vitamina D y el riesgo de infecciones respiratorias 1,2 , y tres dirigidas a evaluar específicamente el riesgo de las infecciones por SARS-CoV-2 [3][4][5] . Para la realización de esta revisión sistemática 2 (posteriormente publicada 1 ), se llevó a cabo una búsqueda de artículos hasta el mes de mayo de 2020 en las plataformas MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science y el sitio ClinicalTrials.gov.…”

“…No obstante, se desconoce la aplicabilidad de estos hallazgos para la prevención de COVID-19. Esta revisión sistemática y meta-análisis 3 , cuyo protocolo estuvo registrado en PROSPERO, realizó una búsqueda sistemática en PubMed/MEDLINE, Scopus y Web of Science hasta junio de 2021, para identificar estudios observacionales y ECA que reporten desenlaces clínicos adversos (admisión en unidades de cuidados intensivos [UCI] y/o mortalidad) en pacientes con COVID-19 que recibieron suplementación con vitamina D vs. quienes no la recibieron. Se consideró tanto el uso de vitamina D previo como posterior al diagnóstico de COVID-19.…”