Association of Vitamin D Serum Levels with Clinical Outcomes in Patients with Acute Decompensated Heart Failure

Background: Heart failure (HF) stands out as a major reason for hospital admissions. Vitamin D deficiency is also associated with a higher risk of cardiovascular diseases. Due to recent conflicting findings, this study aimed to investigate clinical outcomes based on serum vitamin D levels in hospitalized patients with HF. Methods: In this cross-sectional study, 258 hospitalized patients with acute decompensated heart failure (ADHF) were investigated during 2022–2023. Demographic, clinical and laboratory parameters of patients were recorded. They were divided into two groups based on 25-hydroxyvitamin D ([25-OH] D) levels: sufficient ≥30 ng/ml and insufficient <30 ng/ml. Finally, the studied variables were compared between the groups. All data analysis was performed by SPSS version 16.0. Results: In this study, the mean age of the patients in sufficient and insufficient vitamin D groups was 66.91±14.38 and 63.88±13.74 years, respectively. There was no significant difference in terms of age, underlying diseases, smoking status among the groups (P>0.05). The ejection fraction (EF) was lower in patients with insufficient vitamin D (20.66±10.91% vs. 23.98±11.82%). Moreover, vitamin D deficiency was associated with history of hospitalization (P<0.05). The incidence of edema and arrhythmia was higher in patients with insufficient vitamin D (P<0.05) and it was not related to mortality rate during hospitalization in the studied population (P>0.05). Conclusions: Our findings indicate that vitamin D deficiency in patients with ADHF is associated with lower EF, recurrent hospitalizations, edema, and arrhythmia. Consequently, regular monitoring and appropriate treatment of vitamin D levels in these individuals may help mitigate its associated complications to some extent, as much as possible.