ArticleThe Journal of clinical endocrinology and metabolism2023
Low Vitamin D Levels Are Associated With Long COVID Syndrome in COVID-19 Survivors.
Article in The Journal of clinical endocrinology and metabolism, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 57 papers, 3 of them syntheses that pooled it.
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Who cites it
57 citing papers in PubMed, 3 syntheses or guidelines pooled it, 104 citations in OpenAlex.
- Musculoskeletal manifestations in post-acute sequelae of SARS-CoV-2 infection: a systematic review and meta-analysis.Frontiers in public health · 2025Pooled it
- Bone Mineral Density, Bone Biomarkers, and Joints in Acute, Post, and Long COVID-19: A Systematic Review.Viruses · 2024Pooled it
- Pharmacological evaluation of vitamin D in COVID-19 and long COVID-19: recent studies confirm clinical validation and highlight metformin to improve VDR sensitivity and efficacy.Inflammopharmacology · 2024Pooled it
- Vitamin D in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After COVID-19 or Vaccination: A Randomized Controlled Trial.Nutrients · 2026Trial
- Integrative multimodal treatment approach for patients suffering from Post-COVID syndrome: a study based on qualitative interviews with individuals participating in an 11-week day clinic program.Frontiers in public health · 2025Trial
- Chronic cholecalciferol supplementation and adequate vitamin D status are associated with reduced risk of Long COVID.Journal of endocrinological investigation · 2026Article
- Impact of chronic cholecalciferol supplementation and vitamin D status on risk of post-vaccination SARS-CoV-2 breakthrough infection.Endocrine · 2026Observational
- A three-stage family medicine approach to unmasking vitamin D deficiency in a post-COVID-19 prediabetes patient.Journal of family medicine and primary care · 2026Article
- Vitamin D in Gut and Systemic Immune Tolerance and in Infections' Risk: An International Evidence-Based Consensus Statement.Reviews in endocrine & metabolic disorders · 2026Review
- Vitamin D and Health Outcomes: State-of-the-Art Review of Triangulated Evidence and Ongoing Controversies.Current nutrition reports · 2026Review
- Impact of nutrition on long COVID.Sports medicine and health science · 2026Review
- Vitamin D in Infectious Diseases: A Narrative Review Focusing on COVID-19, Long COVID, and Influenza.Nutrients · 2026Review
- Acute SARS-CoV-2 viral load and systemic inflammation are associated with neuropsychiatric and musculoskeletal symptoms in long COVID.PloS one · 2026Article
- Lingering echoes of SARS-CoV-2: mechanistic insights and management of long COVID syndrome.Inflammopharmacology · 2026Review
- Vitamin D in the elderly: the phil-rouge in preventing bone, muscle and adipose deterioration?Archives of endocrinology and metabolism · 2025Review
- A Predictive Model for the Development of Long COVID in Children.International journal of environmental research and public health · 2025Article
- Assessment of Health-Related Quality of Life and Biomarkers in Long COVID: A 12-Month Longitudinal Feasibility Cohort.Journal of clinical medicine · 2025Article
- Association Between Vitamin D Levels and Long COVID Signs and Symptoms.Medical sciences (Basel, Switzerland) · 2025Article
- Prevalence and risk factors for post-COVID-19 syndrome on medical students in Tabuk, Saudi Arabia-2023-2024.Journal of family medicine and primary care · 2025Article
- Morphometric vertebral fractures at hospitalization associate with Long COVID occurrence.Journal of endocrinological investigation · 2025Article
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Authors and funding
7 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
contextLong COVID is an emerging syndrome affecting 50% to 70% of COVID-19 survivors that still lacks predicting factors.
objectiveDue to the extraskeletal effects of vitamin D, we retrospectively assessed the association between 25(OH) vitamin D levels and long COVID in COVID-19 survivors 6 months after hospitalization.
methodsLong COVID was defined according to NICE guidelines. Fifty long COVID and 50 non-long-COVID subjects matched on a 1:1 basis were enrolled from an outpatient clinic post-COVID cohort seen from August to November 2020. Therapies/comorbidities affecting calcium/vitamin D/bone metabolism, and/or admission to the intensive care unit during hospitalization were exclusion criteria. 25(OH) Vitamin D was measured at hospital admission and 6 months after discharge.
resultsWe observed lower 25(OH) vitamin D levels, evaluated at follow-up, in subjects with long COVID than those without (20.1 vs 23.2 ng/mL, P = .03). Regarding the affected health areas evaluated in the entire cohort, we observed lower 25(OH) vitamin D levels in those with neurocognitive symptoms at follow-up (n = 7) than those without (n = 93) (14.6 vs 20.6 ng/mL, P = .042). In patients presenting vitamin D deficiency (<20 ng/mL), both at admission and at follow-up (n = 42), those affected by long COVID (n = 22) presented lower 25(OH) vitamin D levels at follow-up than those not affected (n = 20) (12.7 vs 15.2 ng/mL, P = .041). In multiple regression analyses, lower 25(OH) vitamin D levels at follow-up were the only variable significantly associated with long COVID in our cohort (P = .008, OR 1.09, CI 1.01-1.16).
conclusionCOVID-19 survivors with long COVID have lower 25(OH) vitamin D levels than matched patients without long COVID. Our data suggest that vitamin D levels should be evaluated in COVID-19 patients after hospital discharge. The role of vitamin D supplementation as a preventive strategy of COVID-19 sequelae should be tested in randomized controlled trials.
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