{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T16:20:08Z","timestamp":1789662008411,"version":"4.0.1"},"reference-count":66,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,9,25]],"date-time":"2024-09-25T00:00:00Z","timestamp":1727222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Nutr."],"abstract":"<jats:sec><jats:title>Objective<\/jats:title><jats:p>To analyze the impact of different methods of Vitamin D administration on the prognosis of COVID-19 patients.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>A comprehensive literature search was conducted across four databases: PubMed, Embase, Web of Science, and Cochrane, up to January 5, 2024. Eligible studies included randomized controlled trials and cohort studies that compared Vitamin D supplementation with control groups in COVID-19 patients. Outcomes of interest were mortality rate, ICU (Intensive Care Unit) admission rate, length of hospital stay, and endotracheal intubation rate. Subgroup analyses were performed based on the dosing regimen (single-dose vs. continuous-dose), total Vitamin D intake within 14\u2009days (\u2265100,000\u2009IU vs. &amp;lt;100,000\u2009IU), and baseline serum Vitamin D levels (deficient group: 25OHD\u2009&amp;lt;\u200930\u2009ng\/mL vs. non-restricted group). A random-effects model was employed for meta-analysis to account for heterogeneity among studies.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>A total of 21 studies involving 4,553 participants were included. In terms of mortality, Vitamin D supplementation significantly reduced the mortality rate (RR\u2009=\u20090.72, 95% CI: 0.54\u20130.94, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200954%, <jats:italic>p<\/jats:italic>\u2009=\u20090.02), with continuous dosing being more effective (RR\u2009=\u20090.53, 95% CI: 0.34\u20130.83, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200955%, <jats:italic>p<\/jats:italic>\u2009=\u20090.006) compared to single-dose (RR\u2009=\u20090.88, 95% CI: 0.69\u20131.12, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200921%, <jats:italic>p<\/jats:italic>\u2009=\u20090.3), and lower total doses (&amp;lt;100,000\u2009IU) showing greater benefit (RR\u2009=\u20090.30, 95% CI: 0.21\u20130.44, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u20090%, <jats:italic>p<\/jats:italic>\u2009&amp;lt;\u20090.0001). Mortality was significantly reduced in the Vitamin D-deficient group (25OHD\u2009&amp;lt;\u200930\u2009ng\/mL) (RR\u2009=\u20090.73, 95% CI: 0.59\u20130.89, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u20090%, <jats:italic>p<\/jats:italic>\u2009=\u20090.002) but not in the non-restricted group. Regarding ICU admission, supplementation reduced ICU admission rates (RR\u2009=\u20090.58, 95% CI: 0.38\u20130.88, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200974%, <jats:italic>p<\/jats:italic>\u2009=\u20090.01), with continuous dosing (RR\u2009=\u20090.44, 95% CI: 0.22\u20130.90, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200974%, <jats:italic>p<\/jats:italic>\u2009=\u20090.02) being more effective than single-dose (RR\u2009=\u20090.79, 95% CI: 0.61\u20131.03, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200922%, <jats:italic>p<\/jats:italic>\u2009=\u20090.08), and lower doses (&amp;lt;100,000\u2009IU) providing more significant reduction (RR\u2009=\u20090.31, 95% CI: 0.21\u20130.47, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u20090%, <jats:italic>p<\/jats:italic>\u2009=\u20090.001). ICU admission rates were significantly reduced in the Vitamin D-deficient group (RR\u2009=\u20090.63, 95% CI: 0.42\u20130.93, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u20090%, <jats:italic>p<\/jats:italic>\u2009=\u20090.02) but not in the non-restricted group (RR\u2009=\u20090.59, 95% CI: 0.32\u20131.11, <jats:italic>I<\/jats:italic><jats:sup>2<\/jats:sup> =\u200986%, <jats:italic>p<\/jats:italic>\u2009=\u20090.1). For length of hospital stay, no significant differences were observed between Vitamin D and control groups (MD\u2009=\u2009\u22121, 95% CI: \u22122.16 to 0.16, <jats:italic>p<\/jats:italic>\u2009=\u20090.13), and subgroup analyses by dosing regimen, total dose, and baseline Vitamin D levels also showed no significant differences. Similarly, for endotracheal intubation, there was no significant difference in intubation rates between groups (RR\u2009=\u20090.78, 95% CI: 0.56\u20131.08, <jats:italic>p<\/jats:italic>\u2009=\u20090.13), and subgroup analyses confirmed no significant effect of different dosing strategies or baseline Vitamin D status on intubation rates.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Vitamin D supplementation improves clinical outcomes in COVID-19 patients by reducing mortality and ICU admission rates, particularly when administered continuously with a total dose of less than 100,000\u2009IU over 14\u2009days, and among those with baseline Vitamin D deficiency (25OHD\u2009&amp;lt;\u200930\u2009ng\/mL). However, there were no significant effects on the length of hospital stay or endotracheal intubation rates, regardless of the dosing regimen or baseline Vitamin D levels. These findings emphasize the importance of considering both the total dose over 14\u2009days and baseline Vitamin D status to optimize therapeutic benefits.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fnut.2024.1441847","type":"journal-article","created":{"date-parts":[[2024,9,25]],"date-time":"2024-09-25T21:21:45Z","timestamp":1727299305000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":13,"title":["The impact of supplementing vitamin D through different methods on the prognosis of COVID-19 patients: a systematic review and 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