Canan ŞEHİT KARA, Burcu Baran KETENCİOĞLU, Hümeyra ASLANER, Zeynep TÜRE, Cevat YAZICI, Özgür KARABIYIK, Fahri BAYRAM
Cyprus Journal of Medical Sciences - 2026;11(3):210-217
BACKGROUND/AIMS: Both coronavirus disease 2019 (COVID-19) and vitamin D deficiency (VDD) are widespread health problems today. This study was designed to compare serum 25-hydroxyvitamin D [25(OH)D] levels among three groups: patients with COVID-19 pneumonia, patients with non-COVID-19 pneumonia, and healthy volunteers, and to investigate whether vitamin D levels correlate with laboratory findings and infection severity. MATERIALS AND METHODS: This prospective case-control study was carried out at a single tertiary care centre over four consecutive months between May and August 2020. A total of 90 individuals were enrolled and assigned equally to three groups: 30 with COVID-19 pneumonia, 30 with non-COVID-19 pneumonia, and 30 healthy controls. Multiple linear regression modelling was applied to determine independent predictors of serum 25(OH)D levels. RESULTS: Both pneumonia groups exhibited markedly diminished 25(OH)D concentrations relative to healthy controls, with no statistically significant difference observed between the two pneumonia cohorts. In the multivariate regression model, membership in the healthy control group emerged as the sole independent determinant of elevated 25(OH)D levels. No meaningful correlations were identified among vitamin D concentrations, laboratory indices, and illness severity. CONCLUSION: VDD was common in both COVID-19 and non-COVID-19 related pneumonia groups but was not associated with disease severity. Our results indicate that VDD may influence susceptibility to lower respiratory tract infections rather than disease progression.
