SynthesisClinical endocrinology2022
Association of vitamin D deficiency with COVID-19 infection severity: Systematic review and meta-analysis.
Synthesis in Clinical endocrinology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 63 papers, 7 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
A Randomized Open Label Study to Evaluate Efficacy of Calcitriol Supplementation in COVID-19 Patients With Vitamin D Deficiency
Inclusion of Calcifediol in the Hospital Therapeutic Protocol for Treatment of SARS-CoV-2 Disease (COVID-19). Mortality Analysis. Retrospective Study.
Who cites it
63 citing papers in PubMed, 7 syntheses or guidelines pooled it, 109 citations in OpenAlex.
- Effect of the vitamin D supplementation on clinical outcomes and inflammatory status in COVID-19 patients: an umbrella review.BMC nutrition · 2025Pooled it
- Association Between the Level of Vitamin D and COVID-19 Infection in Children and Adolescents: A Systematic Review.The American journal of tropical medicine and hygiene · 2024Pooled it
- Effect of Vitamin D3 Supplementation on Severe COVID-19: A Meta-Analysis of Randomized Clinical Trials.Nutrients · 2024Pooled it
- Therapeutic effects of vitamin D supplementation on COVID-19 aggravation: a systematic review and meta-analysis of randomized controlled trials.Frontiers in pharmacology · 2024Pooled it
- Prognostic Factors of COVID-19: An Umbrella Review Endorsed by the International Society for Pharmacoepidemiology.Clinical pharmacology and therapeutics · 2023Pooled it
- Association of vitamin D deficiency with COVID-19 infection severity: Systematic review and meta-analysis.Clinical endocrinology · 2022Pooled it
- Vitamin D insufficiency is high in Malaysia: A systematic review and meta-analysis of studies on vitamin D status in Malaysia.Frontiers in nutrition · 2022Pooled it
- Identifying the Most Important Influencing Factors Based on Demographic Information, Nutrition, Physical Activity, Leisure Time, and Underlying Diseases in the Severity of Disease in COVID-19 Patients Using Data Mining Techniques.Health science reports · 2026Article
- The link between nutrient intake and anthropometric indices with COVID-19 infection in pregnant women.BMC pregnancy and childbirth · 2026Article
- Vitamin D deficiency and disease conditions relevant to: Orthopaedic translation.Journal of orthopaedic translation · 2026Review
- Acute Hyperglycaemia, Insulin Resistance, and Cytokine Dysregulation as Predictors of Disease Severity in Non-Diabetic Hospitalised COVID-19 Patients.International journal of molecular sciences · 2026Article
- Vitamin D in Infectious Diseases: A Narrative Review Focusing on COVID-19, Long COVID, and Influenza.Nutrients · 2026Review
- Article
- Hospitalizations for respiratory syncytial virus (RSV) in Sicily from 2008 to 2021: clinical features and predictors of severity.Italian journal of pediatrics · 2025Article
- ALBACOVIDIOL Study: Effect of Calcifediol Treatment on Mortality in Patients Hospitalized for COVID-19: A Retrospective Analysis.Nutrients · 2025Observational
- Vitamin D and COVID-19: Clinical Evidence and Immunological Insights.Life (Basel, Switzerland) · 2025Review
- Evidence of rapid rise in population immunity from SARS-CoV-2 subclinical infections through pre-vaccination serial serosurveys in Pakistan.Journal of global health · 2025Article
- Association between vitamin D deficiency and clinical outcome in patients with COVID-19 in the post-Omicron phase.Frontiers in nutrition · 2025Article
- Association of vitamin A and D deficiency and the presence of sepsis in the geriatric population: a cross-sectional study.Frontiers in nutrition · 2025Article
- Evaluation of vitamin D status, vitamin D receptor expression, and innate immune mediators in COVID-19.Frontiers in endocrinology · 2025Observational
3 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundWe sought to evaluate the association between vitamin D deficiency and the severity of coronavirus disease 2019 (COVID-19) infection.
methodsMultiple databases from 1 January 2019 to 3 December 2020 were searched for observational studies evaluating the association between vitamin D deficiency and severity of COVID-19 infection. Independent reviewers selected studies and extracted data for the review. The main outcomes of interest were mortality, hospital admission, length of hospital stay and intensive care unit admission.
resultsSeventeen observational studies with 2756 patients were included in the analyses. Vitamin D deficiency was associated with significantly higher mortality (odds ratio [OR]: 2.47, 95% confidence interval [CI]: 1.50-4.05; 12 studies; hazard ratio [HR]: 4.11, 95% CI: 2.40-7.04; 3 studies), higher rates of hospital admissions (OR: 2.18, 95% CI: 1.48-3.21; 3 studies) and longer hospital stays (0.52 days; 95% CI: 0.25-0.80; 2 studies) as compared to nonvitamin D deficient status. Subgroup analyses based on different cut-offs for defining vitamin D deficiency, study geographic locations and latitude also showed similar trends.
conclusionsVitamin D deficiency is associated with greater severity of COVID-19 infection. Further studies are warranted to determine if vitamin D supplementation can decrease the severity of COVID-19.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.