Observational studyThe journal of nutrition, health & aging2021
Impact of Serum 25(OH) Vitamin D Level on Mortality in Patients with COVID-19 in Turkey.
Observational study in The journal of nutrition, health & aging, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 50 papers, 11 of them syntheses that pooled it.
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Who cites it
50 citing papers in PubMed, 11 syntheses or guidelines pooled it, 117 citations in OpenAlex.
- Is the vitamin D status of patients with COVID-19 associated with reduced mortality? A systematic review and meta-analysis.Archives of endocrinology and metabolism · 2023Pooled it
- Identification of Parameters Representative of Immune Dysfunction in Patients with Severe and Fatal COVID-19 Infection: a Systematic Review and Meta-analysis.Clinical reviews in allergy & immunology · 2023Pooled it
- Does vitamin D supplementation reduce COVID-19 severity?: a systematic review.QJM : monthly journal of the Association of Physicians · 2022Pooled it
- Physiological factors affecting the mechanical performance of peripheral muscles: A perspective for long COVID patients through a systematic literature review.Frontiers in physiology · 2022Pooled it
- The role of vitamin D in the age of COVID-19: A systematic review and meta-analysis.International journal of clinical practice · 2021Pooled it
- Pooled it
- Association of Vitamin D Status with SARS-CoV-2 Infection or COVID-19 Severity: A Systematic Review and Meta-analysis.Advances in nutrition (Bethesda, Md.) · 2021Pooled it
- The link between COVID-19 and VItamin D (VIVID): A systematic review and meta-analysis.Metabolism: clinical and experimental · 2021Pooled it
- Micronutrients Deficiency, Supplementation and Novel Coronavirus Infections-A Systematic Review and Meta-Analysis.Nutrients · 2021Pooled it
- The role of vitamin D deficiency on COVID-19: a systematic review and meta-analysis of observational studies.Epidemiology and health · 2021Pooled it
- Vitamin D Status and SARS-CoV-2 Infection and COVID-19 Clinical Outcomes.Frontiers in public health · 2021Pooled it
- Low 1,25-dihydroxyvitamin D levels are associated with severe COVID-19: an observational study in hospitalized patients.Frontiers in nutrition · 2026Article
- Comparison of the role of vitamin D in normal organs and those affected by COVID-19.International journal of medical sciences · 2025Review
- Vitamin D: A key player in COVID-19 immunity and lessons from the pandemic to combat immune-evasive variants.Inflammopharmacology · 2024Review
- Association between Average Vitamin D Levels and COVID-19 Mortality in 19 European Countries-A Population-Based Study.Nutrients · 2023Review
- A systematic review: The relationship of COVID-19 to iron, zinc, and vitamin D.Journal of family medicine and primary care · 2023Article
- Is Serum 25-Hydroxyvitamin D Level Associated with Severity of COVID-19? A Retrospective Study.Journal of clinical medicine · 2023Article
- Hypocalcemia is associated with adverse outcomes in patients hospitalized with COVID-19.Endocrine · 2023Article
- Shedding light on the next pandemic path, from outpatient to ICU, the effect of vitamin D deficiency in the SARS-CoV-2 pandemic.Frontiers in nutrition · 2023Article
- Vitamin D-A prominent immunomodulator to prevent COVID-19 infection.International journal of rheumatic diseases · 2023Review
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Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundBecause of the lack of sufficient data, we aimed to investigate the role of serum 25(OH) vitamin D level on COVID severity and related mortality.
methodsThis was a retrospective observational study. Data, including sociodemographic features, clinical characteristics, and laboratory data, and 25(OH) vitamin D levels were recorded for each study participant. Patients were stratified into different vitamin D groups; Normal (Serum 25(OH) vitamin D level >30 ng/mL), Vitamin D insufficiency (21-29 ng/mL), and deficiency (<20 ng/mL). The severity of COVID was classified according to the Chinese Clinical Guideline for classification of COVID-19 severity. Mortality data were determined for participants. Univariate and multivariate Logistic regression analysis was performed to determine independent predictors of in-hospital mortality.
resultsOverall, 149 COVID-19 patients (females 45.6%, mean age 63.5 ± 15.3 (range 24-90 years) years) were included. Forty-seven patients (31.5%) had moderate COVID-19, whereas 102 patients (68.5%) had severe-critical COVID-19. The mean 25(OH) vitamin D level was 15.2 ± 10.3 ng/mL. Thirty-four (22.8%) and 103 (69.1%) patients had vitamin D insufficiency and deficiency, respectively. Mean serum 25(OH) vitamin D level was significantly lower in patients with severe-critical COVID-19 compared with moderate COVID-19 (10.1 ± 6.2 vs. 26.3 ± 8.4 ng/mL, respectively, p<0.001). Vitamin D insufficiency was present in 93.1% of the patients with severe-critical COVID-19. Multivariate logistic regression analysis revealed that only lymphocyte count, white blood cell count, serum albumin and, 25(OH) vitamin D level were independent predictors of mortality.
conclusionSerum 25(OH) vitamin D was independently associated with mortality in COVID-19 patients.
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