Higher 25(OH)D Levels at Admission Predict a Favorable Disease Evolution in Moderate-to-Severe COVID-19 Patients
et al., International Journal of Molecular Sciences, doi:10.3390/ijms27083541, Apr 2026
Vitamin D for COVID-19
8th treatment shown to reduce risk in
October 2020, now with p < 0.00000000001 from 137 studies, recognized in 18 countries.
No treatment is 100% effective. Protocols
combine treatments.
6,500+ studies for
210+ treatments. c19early.org
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Prospective observational cohort study of 139 hospitalized moderate-to-severe COVID-19 patients showing that higher baseline vitamin D levels predict favorable clinical outcomes.
This is the 231st COVID-19 sufficiency study for vitamin D, which collectively show higher levels reduce risk with p<0.0000000001.
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risk of no recovery, 59.2% lower, OR 0.41, p = 0.04, high D levels (≥11 ng/mL) 93, low D levels (<11 ng/mL) 46, adjusted per study, inverted to make OR<1 favor high D levels (≥11 ng/mL), risk of no discharge alive and/or NEWS2 ≤ 2 for at least 24 h within 14 days, multivariable, Table 6, RR approximated with OR.
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| Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates |
Rizzi et al., 16 Apr 2026, prospective, Italy, peer-reviewed, 21 authors, study period January 2021 - May 2021.
Contact: pierpaolo.sainaghi@med.uniupo.it (corresponding author), roberta.rolla@med.uniupo.it, donato.colangelo@med.uniupo.it, federica.vincenzi@uniupo.it, eleonora.rizzi@maggioreosp.novara.it, veronica.vassia@gmail.com.
Abstract:
Article
Higher 25(OH)D Levels at Admission Predict a Favorable Disease Evolution in Moderate-to-Severe COVID-19 Patients
Manuela Rizzi 1,† , Federica Vincenzi 2,† , Stelvio Tonello 2 , Eleonora Rizzi 3 , Giuseppe Francesco Casciaro 3 , Erica Matino 3 , Martina Costanzo 3 , Erika Zecca 3 , Alessandro Croce 3 , Anita Pedrinelli 3 , Veronica Vassia 3 , Raffaella Landi 3 , Iris Zeqaj 3 , Francesca Boccafoschi 1 , Paolo Amedeo Tillio 4 , Roberta Rolla 1,4 , Umberto Dianzani 1,4,5,6 , Luigi Mario Castello 2,7 , Mario Pirisi 2,3,5,6 , Donato Colangelo 1 and Pier Paolo Sainaghi 2,3,5,6, *
- 1 Dipartimento di Scienze della Salute (DiSS), Universit à del Piemonte Orientale (UPO), 28100 Novara, Italy; roberta.rolla@med.uniupo.it (R.R.); donato.colangelo@med.uniupo.it (D.C.)
- 2 Dipartimento di Medicina Traslazionale (DiMeT), Universit à del Piemonte Orientale (UPO), 28100 Novara, Italy; federica.vincenzi@uniupo.it (F.V.)
- 3 Internal Medicine and Rheumatology Department, Azienda Ospedaliero-Universitaria 'Maggiore della Carit à ' di Novara, 28100 Novara, Italy; eleonora.rizzi@maggioreosp.novara.it (E.R.); veronica.vassia@gmail.com (V.V.)
- 4 Clinical Biochemistry Laboratory, Azienda Ospedaliero-Universitaria 'Maggiore della Carit à ' di Novara, 28100 Novara, Italy
- 5 IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), Universit à del Piemonte Orientale (UPO), 28100 Novara, Italy
- 6 CAAD(Center for Translational Research on Allergic and Autoimmune Diseases), Universit à del Piemonte Orientale (UPO), 28100 Novara, Italy
- 7 Internal Medicine Unit, Azienda Ospedaliero-Universitaria 'SS. Antonio e Biagio e Cesare Arrigo', 15100 Alessandria, Italy
* Correspondence: pierpaolo.sainaghi@med.uniupo.it
- † These authors contributed equally to this work.
Abstract
Research into effective predictive markers and therapeutic interventions for COVID-19 remains of considerable interest. Vitamin D may be relevant, especially in frail populations in whom deficiency is more prevalent. In this prospective observational cohort study, 139 patients with moderate-to-severe COVID-19 who were hospitalized during the third wave of the pandemic in Italy were enrolled. Plasma vitamin D concentrations (both 25-hydroxyvitamin D-25(OH)D and 1,25-dihydroxyvitamin D-1,25(OH)2D) together with parathyroid hormone levels were measured using a chemiluminescent assay validated for clinical use on automated laboratory platforms. Plasma vitamin D levels were below the sufficiency threshold. Notably, 25(OH)D concentrations were significantly lower in patients who experienced a negative outcome (11.10 [8.80-16.20] vs. 15.25 [9.90-24.80] ng/mL, p = 0.0450) and significantly higher in patients with rapid clinical recovery (15.25 [10.70-24.80] vs. 13.30 [7.47-19.60] ng/mL, p = 0.0446) compared with all other patients. Through multivariable logistic regression analysis, higher 25(OH)D levels at the time of hospitalization were confirmed as an independent predictor of favorable outcome. A plasma 25(OH)D concentration above 11.10 ng/mL predicted favorable disease resolution, with a positive likelihood ratio of 1.40 (IQR: 1.05-1.87). In conclusion, our findings support plasma vitamin D levels as an independent predictor of clinical outcomes in patients hospitalized with COVID-19 pneumonia.
Keywords: COVID-19; vitamin D; biomarker; clinical outcomes
Academic Editor: Monica Gelzo Received: 24 February 2026 Revised: 11 April 2026 Accepted: 13 April 2026 Published: 16 April..
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"abstract": "<jats:p>Research into effective predictive markers and therapeutic interventions for COVID-19 remains of considerable interest. Vitamin D may be relevant, especially in frail populations in whom deficiency is more prevalent. In this prospective observational cohort study, 139 patients with moderate-to-severe COVID-19 who were hospitalized during the third wave of the pandemic in Italy were enrolled. Plasma vitamin D concentrations (both 25-hydroxyvitamin D-25(OH)D and 1,25-dihydroxyvitamin D-1,25(OH)2D) together with parathyroid hormone levels were measured using a chemiluminescent assay validated for clinical use on automated laboratory platforms. Plasma vitamin D levels were below the sufficiency threshold. Notably, 25(OH)D concentrations were significantly lower in patients who experienced a negative outcome (11.10 [8.80–16.20] vs. 15.25 [9.90–24.80] ng/mL, p = 0.0450) and significantly higher in patients with rapid clinical recovery (15.25 [10.70–24.80] vs. 13.30 [7.47–19.60] ng/mL, p = 0.0446) compared with all other patients. Through multivariable logistic regression analysis, higher 25(OH)D levels at the time of hospitalization were confirmed as an independent predictor of favorable outcome. A plasma 25(OH)D concentration above 11.10 ng/mL predicted favorable disease resolution, with a positive likelihood ratio of 1.40 (IQR: 1.05–1.87). In conclusion, our findings support plasma vitamin D levels as an independent predictor of clinical outcomes in patients hospitalized with COVID-19 pneumonia.</jats:p>",
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