Clinical Phenotypes, Comorbidities, and Exacerbations according to Serum 25-OH Vitamin D and Plasma Fibrinogen Levels in Chronic Obstructive Pulmonary Disease
This retrospective study analyzed patients with COPD whose inflammatory marker levels, especially plasmafibrinogen and 25-OH vitamin D levels, had been examined. A correlation analysis was conducted for inflammatory markers and 25-OH vitamin D. Clinical characteristics, comorbidities and exacerbation rates were compared among four groups based on plasmafibrinogen concentrations (threshold, 350 mg/dL) and 25-OH vitamin D levels (threshold, 20 ng/mL).
RESULTS:
Among 611 patients with COPD, 236 were included in the study. The levels of inflammatory markers had no statistical correlation with the serum 25-OH vitamin D levels. The four groups showed no statistically significant differences in age, sex, smokinghistory, inhaler use, and severity of comorbidities. Patients with high plasmafibrinogen concentrations and low 25-OH vitamin D levels had lower lung function, higher severity index, and higher annual rate of severe exacerbations 12 months before (0.23/year) and after (0.41/year) the measurement of 25-OH vitamin D levels than did the other patients.