Unraveling the roles of vitamin D status and melanin during Covid‑19 (Review).
International journal of molecular medicine. 2021;(1):92-100
As the coronavirus disease 2019 (COVID‑19) continues to spread worldwide, it has become evident that the morbidity and mortality rates clearly vary across nations. Although several factors may account for this disparity, striking differences within and between populations indicate that ethnicity might impact COVID‑19 clinical outcomes, reflecting the 'color of disease'. Therefore, the role of key biological variables that could interplay with viral spreading and severity indices has attracted increasing attention, particularly among non‑Caucasian populations. Although the links between vitamin D status and the incidence and severity of COVID-19 remain elusive, several lines of emerging evidence suggest that vitamin D signaling, targeting several immune‑mediated pathways, may offer potential benefits at different stages of SARS-CoV-2 infection. Given that the vitamin D status is modulated by several intrinsic and extrinsic factors, including skin type (pigmentation), melanin polymers may also play a role in variable COVID‑19 outcomes among diverse population settings. Moreover, apart from the well‑known limiting effects of melanin on the endogenous production of vitamin D, the potential crosstalk between the pigmentary and immune system may also require special attention concerning the current pandemic. The present review article aimed to shed light on a range of mostly overlooked host factors, such as vitamin D status and melanin pigments, that may influence the course and outcome of COVID‑19.
Potential immunomodulatory effects of vitamin D in the prevention of severe coronavirus disease 2019: An ally for Latin America (Review).
International journal of molecular medicine. 2021;(4)
Currently, the world is under a pandemic of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), responsible for coronavirus disease 2019 (COVID‑19). This disease is characterized by a respiratory syndrome that can progress to an acute respiratory distress syndrome. To date, limited effective therapies are available for the prevention or treatment of COVID‑19; therefore, it is necessary to propose novel treatment options with immunomodulatory effects. Vitamin D serves functions in bone health and has been recently reported to exert protective effects against respiratory infections. Observational studies have demonstrated an association between vitamin D deficiency and a poor prognosis of COVID‑19; this is alarming as vitamin D deficiency is a global health problem. In Latin America, the prevalence of vitamin D deficiency is unknown, and currently, this region is in the top 10 according to the number of confirmed COVID‑19 cases. Supplementation with vitamin D may be a useful adjunctive treatment for the prevention of COVID‑19 complications. The present review provides an overview of the current knowledge of the potential immunomodulatory effects of vitamin D in the prevention of COVID‑19 and sets out vitamin D recommendations for the Latin American population.
Low vitamin D status is associated with coronavirus disease 2019 outcomes: a systematic review and meta-analysis.
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases. 2021;:58-64
BACKGROUND Observational studies suggest that the risk and clinical prognosis of coronavirus disease 2019 (COVID-19) are related to low vitamin D status; however, the data are inconsistent. OBJECTIVES We conducted a systematic review and meta-analysis to assess the association between low vitamin D status and COVID-19. METHODS A systematic search was conducted with PubMed, Embase, and the Cochrane Library from database inception to September 25, 2020. The standardized mean difference (SMD) or odds ratio (OR) and corresponding 95% confidence interval (CI) was applied to estimate pooled results. Random - or fixed-effect models based on heterogeneity were used for the meta-analysis. Funnel plots and Egger regression tests were used to assess publication bias. RESULTS A total of ten articles with 361,934 participants were selected for meta-analysis. Overall, the pooled OR in the fixed-effect model showed that vitamin D deficiency or insufficiency was associated with an increased risk of COVID-19 (OR = 1.43, 95% CI 1.00-2.05). In addition, COVID-19-positive individuals had lower vitamin D levels than COVID-19-negative individuals (SMD = -0.37, 95% CI = -0.52 to -0.21). Significant heterogeneity existed in both endpoints. Funnel plots and Egger regression tests revealed significant publication bias. CONCLUSIONS This systematic review and meta-analysis indicated that low vitamin D status might be associated with an increased risk of COVID-19 infection. Further studies are needed to evaluate the impact of vitamin D supplementation on the clinical severity and prognosis in patients with COVID-19. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration no: CRD42020216740.
Evidence Regarding Vitamin D and Risk of COVID-19 and Its Severity.
Vitamin D deficiency co-exists in patients with COVID-19. At this time, dark skin color, increased age, the presence of pre-existing illnesses and vitamin D deficiency are features of severe COVID disease. Of these, only vitamin D deficiency is modifiable. Through its interactions with a multitude of cells, vitamin D may have several ways to reduce the risk of acute respiratory tract infections and COVID-19: reducing the survival and replication of viruses, reducing risk of inflammatory cytokine production, increasing angiotensin-converting enzyme 2 concentrations, and maintaining endothelial integrity. Fourteen observational studies offer evidence that serum 25-hydroxyvitamin D concentrations are inversely correlated with the incidence or severity of COVID-19. The evidence to date generally satisfies Hill's criteria for causality in a biological system, namely, strength of association, consistency, temporality, biological gradient, plausibility (e.g., mechanisms), and coherence, although experimental verification is lacking. Thus, the evidence seems strong enough that people and physicians can use or recommend vitamin D supplements to prevent or treat COVID-19 in light of their safety and wide therapeutic window. In view of public health policy, however, results of large-scale vitamin D randomized controlled trials are required and are currently in progress.
Exploring links between vitamin D deficiency and COVID-19.
PLoS pathogens. 2020;(9):e1008874
Coronavirus Disease 2019 (COVID-19) pandemic remains a major public health threat in most countries. The causative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus can lead to acute respiratory distress syndrome and result in mortality in COVID-19 patients. Vitamin D is an immunomodulator hormone with established effectiveness against various upper respiratory infections. Vitamin D can stall hyper-inflammatory responses and expedite healing process of the affected areas, primarily in the lung tissue. Thus, there are ecological and mechanistic reasons to promote exploration of vitamin D action in COVID-19 patients. As no curative drugs are available currently for COVID-19, we feel that the potential of vitamin D to alter the course of disease severity needs to be investigated. Clinical studies may be undertaken to address the value of vitamin D supplementation in deficient, high-risk COVID-19 patients.
Covid-19 and vit-d: Disease mortality negatively correlates with sunlight exposure.
Spatial and spatio-temporal epidemiology. 2020;:100362
The novel COVID-19 disease is a contagious acute respiratory infectious disease whose causative agent has been demonstrated to be a new virus of the coronavirus family, SARS-CoV-2. Alike with other coronaviruses, some studies show a COVID-19 neurotropism, inducing de-myelination lesions as encountered in Guillain-Barré syndrome. In particular, an Italian report concluded that there is a significant vitamin D deficiency in COVID-19 infected patients. In the current study, we applied a Pearson correlation test to public health as well as weather data, in order to assess the linear relationship between COVID-19 mortality rate and the sunlight exposure. For instance in continental metropolitan France, average annual sunlight hours are significantly (for a p-value of 1.532 × 10-32) correlated to the COVID-19 mortality rate, with a Pearson coefficient of -0.636. This correlation hints at a protective effect of sunlight exposure against COVID-19 mortality. This paper is proposed to foster academic discussion and its hypotheses and conclusions need to be confirmed by further research.
Perspective: improving vitamin D status in the management of COVID-19.
European journal of clinical nutrition. 2020;(6):856-859
Evidences for a protective role of vitamin D in COVID-19.
RMD open. 2020;(3)
Vitamin D deficiency and the COVID-19 pandemic.
Journal of global antimicrobial resistance. 2020;:133-134
• Vitamin D deficiency is very common. • Randomised controlled trials showed that vitamin D decreases acute respiratory infections (ARIs). • Vitamin D deficiency is an easily modifiable factor of ARIs. • Daily vitamin D supplementation with moderate doses is safe and cheap. • Even a small decrease in COVID-19 infections would easily justify this intervention.
Vitamin D deficiency in patients with diabetes and COVID- 19 infection.
Diabetes & metabolic syndrome. 2020;(5):1033-1035
BACKGROUND AND AIMS Data show that vitamin D deficiency may play a role in patients with diabetes mellitus and COVID-19 infection. In this article, we review evidence of vitamin D deficiency and COVID-19 infection in context of diabetes mellitus. METHODS A literature search was carried out by using the key term 'COVID 19' combined with 'Diabetes', 'Vitamin D', 'Extra skeletal effects', 'immunity', 'infection', 'India' from Pub Med (National Library of Medicine, Bethesda, MD and Google Scholar from December 2019 to May 2020. A manual search of the references was also carried out. RESULTS Vitamin D deficiency has been linked to increased morbidity and mortality in COVID -19 infections but convincing data on diabetic subgroup of patients in particular is still awaited. CONCLUSION Robust studies are required to ascertain if Vitamin D supplementation could be beneficial in patients with diabetes and COVID-19.