Cholecalciferol level and its impact on COVID-19 patients.

Area of Science:

• Immunology and Infectious Diseases
• Nutritional Science
• Critical Care Medicine

Background:

• Vitamin D (cholecalciferol) is vital for immune function, bone health, and overall well-being.
• Vitamin D deficiency is common and associated with increased risk of severe COVID-19.
• The role of vitamin D in modulating the inflammatory response in COVID-19 requires further investigation.

Purpose of the Study:

• To investigate the association between serum 25-hydroxy vitamin D (25 OHD) levels and COVID-19 severity.
• To determine if vitamin D levels predict mortality in patients with severe COVID-19.
• To explore the correlation between vitamin D levels and inflammatory markers in COVID-19 patients.

Main Methods:

• Prospective study of 414 severely symptomatic COVID-19 patients (June 2020 - October 2021).
• Measurement of serum vitamin D3 (cholecalciferol) levels on admission.
• Correlation analysis of vitamin D3 levels with inflammatory markers (ferritin, D-dimer, CRP, LDH, neutrophil-to-lymphocyte ratio), disease severity, mechanical ventilation duration, and mortality.

Main Results:

• Lower vitamin D3 levels were significantly associated with severe COVID-19 and mortality (58.25 nmol/L in non-survivors vs. 103.97 nmol/L in survivors, P < 0.001).
• A strong inverse correlation was observed between initial vitamin D3 levels and inflammatory markers (ferritin, D-dimer, CRP, LDH) on days 5 and 10.
• Vitamin D3 levels showed a strong inverse correlation with disease severity on chest CT scans, length of hospital stay, and mechanical ventilation days. A cutoff of <60 nmol/L predicted mortality.

Conclusions:

• Low serum cholecalciferol levels are strongly inversely correlated with COVID-19 cytokine storm markers.
• Vitamin D deficiency is an independent predictor of severity and mortality in COVID-19 patients.
• Maintaining adequate vitamin D levels may be a critical factor in managing severe COVID-19.