Abstract The relationship between 25-OH Vitamin D3 and hospital death continues to be a topic of controversy. At present, the available evidence regarding the relationship between 25-OH Vitamin D and hospital death is inadequate. Therefore, we conducted a cross-sectional study involving 197 sepsis-3 participants from MIMIC-IV. Basic information, laboratory indicators, underlying Disease, therapeutic medications and tools, disease score were obtained from all participants. Serum 25-OH Vitamin D was collected on Intensive Care Unit (ICU) admission, and inpatient mortality were analyzed. The logistic regression, fitting curve and interaction effects were utilized to substantiate the correlation of serum 25-OH Vitamin D with inpatient mortality. Furthermore, interaction and subgroup analyses were evaluated for the consistency of these correlations. A total of 197 patients were included in the analysis, with an average age of 59.8 years and 43.1% male. The mean 25-OH vitamin D level in the cohort was 21 ng/mL. We observed no significant association between higher 25-OH vitamin D levels and increased inpatient mortality rates. The in-hospital mortality did not differ among patients vitamin D deficiency, insufficiency and sufficiency group (15.7% vs 17.4% vs 24.5%, p=0.417). A multivariable adjusted logistic regression model showed that vitamin D levels could not predict in-hospital mortality (OR 1.02 95% CI: 0.98~1.05, p=0.342, Model 3). In conclusion, 25-OH vitamin D detected upon ICU admission was not associated with in-hospital mortality in patients with sepsis. Keywoeds:25-OH vitamin D,sepsis,mortality

The authors have declared no competing interest.

This study did not receive any funding

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