Vitamin D Status and Immune-inflammatory Status in Different UK Populations With COVID-19 Infection

Study Overview
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Brief Summary
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Hypothesis: Serum Vitamin D (25(OH)D) is significantly lower in severe versus non-severe COVID-19 infections and that this is a function of ethnicity. There is an association between vitamin D status and various cytokines (pro-inflammatory molecules). The primary objective of this research is to provide a snap shot of vitamin D status in patients from the South-East London area by age, sex, ethnicity and BMI and demonstrate ethnic differences in vitamin D status as well as its associations with severe vs non-severe COVID-19 infections. The secondary objective is to determine if there is an association between vitamin D status and various cytokines (pro-inflammatory molecules) and severity of disease.

Detailed Description
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Worldwide there has been over 6 million cases and 380,810 deaths from Coronavirus 2019 (COVID-19) (ECDC June 2020). According to the European Centre for Disease Prevention and Control (ECDC) risk factors for critical illness include elderly people above 70 years of age, and people with underlying conditions such as hypertension, diabetes, cardiovascular disease, chronic respiratory disease, immune compromised status and obesity (73.4% of critically ill patients with BMI 30-40). In addition, in the UK 32% of critically ill COVID-19 patients are of Black or Asian ethnic-minority background (ICNARC April 10th, 2020). There is therefore an urgent need to fully understand the risk factors for severe COVID-19 infection and find an effective treatment. In COVID-19 infection those patients that required intensive care treatment have high circulating cytokines and chemokines TNF-α, IL-2, IL-6, IL-7, IL-9, IL-17, IFN-γ, MCP-1 and MIP-1α. Severe COVID-19 infection appears therefore to be associated with a damaging hyperinflammation state. In addition to a dysregulated cytokine response there is also dysregulation of immune cell populations in COVID-19 infection. For example, there is low T regs, NK cell and CD8+ and CD4+ T cells in severe COVID-19 infection. Moreover, CD8+ T cells appear to be an independent predictor for COVID-19 severity and treatment efficacy. Other than genetic factors, e.g. HLA, which may predispose to severe COVID-19, vitamin D (25(OH)D) may be important for several reasons. Firstly because 25(OH)D inadequacy is prevalent in European and US older adults (>60 years), Black and Asian minority ethnic population groups and in those with a high BMI. Secondly because 25(OH)D is known to have important immunoregulatory roles e.g. in downregulating pro-inflammatory cytokines TNF-α, IL-1, IL-2, IL-6, IL-8, IL-17, IFN-γ and upregulating anti-inflammatory TGFβ and IL-10. 25(OH)D also promotes Treg and effector CD8+ T cell differentiation and expansion. Furthermore, 25(OH)D has a role in preventing and reducing human respiratory infections e.g. influenza and in experimental animals is positively associated with virus specific CD8+ T cells. Vitamin D may also be an important modulator of hyperinflammatory response in patients with Covid-19 infection through cytokine storm suppression. As part of the Government's response to Covid-19, Public Health England has re-issued existing advice on vitamin D: https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/ This study will provide important information on vitamin D status as a possible risk factor in relation to COVID-19 infection in UK elderly and ethnic minority populations. Furthermore, the data generated could also have important implications for future supplementation and or vaccination strategies for COVID-19.

Official Title
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Retrospective Pilot Study of Vitamin D Status and Immune-inflammatory Status in Different UK Populations With COVID-19 Infection

Conditions
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Covid19

Intervention / Treatment
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* Other: no intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients tested for vitamin D and Covid-19 Exclusion Criteria: not applicable

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Audit 1<br>All vitamin D results performed since January 2020 (N=  15000) together with age, weight and height if available, ethnicity and other relevant laboratory markers (Ca, adjusted calcium, PTH, Mg, phosphate, liver and renal profile, Covid-19 screening, CRP, Haematinics, FBC) | Other: no intervention<br>* There will be no intervention<br>|
| Audit 2<br>All Covid-19 screening results together with vitamin D, ethnicity, age, weight, height, length of stay in hospital including ICU (if applicable), type of illness, recovered or not, associated health conditions, CRP, Ferritin, Haematinics, vitamin A and E, procalcitonin, LDH, INR, fibrinogen, FBC, D-dimers, CK, Troponin-T, cytokines, renal function and electrolytes from patients tested at GSTT NHS Trust. | Other: no intervention<br>* There will be no intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Collecting vitamin D results in patients from the South-East London area together with age, sex, ethnicity and BMI and other relevant laboratory results. | All vitamin D results performed by the Nutristasis Unit at St. Thomas' since January 2020 (N=  15000) together with age, weight and height if available, ethnicity and other relevant laboratory markers (Ca, adjusted calcium, PTH, Mg, phosphate, liver and renal profile, Covid-19 screening, CRP, Haematinics, FBC) if they were tested within two weeks of the sample being measured for vitamin D will be acquired. The results of this audit will provide a snap shot of vitamin D status in patients from the South-East London area by age, sex, ethnicity and BMI (weight in kg/height2). Correlation analysis will also be undertaken with other laboratory parameters. | January-June 2020 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Collecting Covid-19 screening results together with age, sex, ethnicity and BMI and other relevant laboratory results. | All Covid-19 screening results together with vitamin D (nmol/L), ethnicity, age (yrs), weight (m) and height to obtain BMI, length of stay in hospital including ICU in days (if applicable), type of illness, recovered or not (y or no), associated health conditions, CRP, Ferritin, Haematinics, vitamin A and E, procalcitonin, LDH, INR, fibrinogen, FBC, D-dimers, CK, Troponin-T, cytokines, renal function and electrolytes will be collected from patients tested at GSTT NHS Trust. We expect that only a small number of patients who had Covid-19 screening performed would have had vitamin D, cytokines and other markers measured. However, we estimate that we will be able to identify a sufficient number of Covid-19 patients for regression and correlation analysis from this data. | March-June 2020 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin D, cytokines, ethnicity, pro-inflammatory molecules