key: cord-1043732-skwu025v
authors: Roy, Akangsha Sur; Matson, Montgomery; Herlekar, Rahul
title: Response to ‘Vitamin D concentrations and COVID-19 infection in UK Biobank’
date: 2020-06-04
journal: Diabetes Metab Syndr
DOI: 10.1016/j.dsx.2020.05.049
sha: 0329564bb80824eaaaa0a97aebe10ec1fe735363
doc_id: 1043732
cord_uid: skwu025v

nan

Dear Editor,

We read with great interest the study by Hastie and colleagues [1] , which found there was not an independent association between vitamin D concentration and COVID-19. They suggest that vitamin D deficiency is unlikely to be an underlying mechanism for the disproportional incidence in ethnic minorities. Their study used data from 348,598 participants recruited by UK Biobank, whose baseline 25(OH)D was recorded between 2006 and 2010. This was linked with the results of COVID-19 tests of 1474 participants.

Although the vitamin D was measured over a decade ago, the authors suggest that it remains representative of the current level as concentrations 'generally track over time'. However, they cited the findings of a study [2] that measured intraindividual variation in 25(OH)D over a 5-year period in post-menopausal women. This assumption may not be valid for this 14-year difference with both male and female participants. Furthermore, we note that only 1474 out the 348,598 were tested for COVID-19. It is possible that some COVID-19 positive participants were not tested due to having no or mild symptoms and reservation of tests for inpatients. This would result in an under-estimation of COVID-19 infection.

The authors conclude that vitamin D levels are unlikely to 'assess risk' of COVID-19 in clinical practice. Whilst deficiency may not be associated with risk of incidence, it may still be associated with risk of severity which this paper does not examine. For example, a study showed that vitamin D was an independent predictor of mortality in patients with pneumonia. [3] Additionally, the authors infer that vitamin D supplements are unlikely to be therapeutically effective. We wish to highlight that there have been many well-established studies supporting the anti-viral effects of vitamin D [4] , through mechanisms affecting physical barriers and the modulation of innate and adaptive immunity. [5] Indeed, a large meta-analysis has shown a therapeutic role of its supplementation in acute respiratory tract infection [6] , and we argue that similar interventional trials are required for COVID-19.

We thank the authors for sharing their findings, but for now, the association between vitamin D and COVID-19 remains unclear. Future observational studies should involve large cohorts with low selection bias, and short times between 25(OH)D measurement and COVID-19 testing. Similar to this study, the statistical analysis should also account for confounding factors. Additionally, well-designed randomised controlled trials may reveal the efficacy of vitamin D as an adjuvant therapy. Indeed, this is a low cost and readily available treatment, making it an appealing prospect.

Vitamin D concentrations and COVID-19 infection in UK Biobank

Intraindividual Variation in Plasma 25-Hydroxyvitamin D Measures 5 Years Apart among Postmenopausal Women

Addition of Vitamin D Status to Prognostic Scores Improves the Prediction of Outcome in Community-Acquired Pneumonia

Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths

Self-Care for Common Colds: The Pivotal Role of Vitamin D, Vitamin C, Zinc, and Echinacea in Three Main Immune Interactive Clusters (Physical Barriers, Innate and Adaptive Immunity) Involved during an Episode of Common Colds-Practical Advice on Dosages and on the Time to Take These Nutrients/Botanicals in order to Prevent or Treat Common Colds, Evid.-Based Complement

Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data

Declaration of Competing Interest -The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.The authors whose names are listed immediately below certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patentlicensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

The authors whose names are listed immediately below report the following details of affiliation or involvement in an organization or entity with a financial or non-financial interest in the subject matter or materials discussed in this manuscript. Please specify the nature of the conflict on a separate sheet of paper if the space below is inadequate.

Rahul Herlekar