Vitamin D in COPD with CKD

Abstract

Introduction: Vitamin D deficiency is common in both patients with chronic obstructive pulmonary disease (COPD), as well as in those with chronic kidney disease (CKD). Aim: To investigate the role of vitamin D in patients with COPD and CKD. Materials and methods: A prospective study of 90 patients with COPD follow-up during the June 2023 – January 2025 period. They were divided into two groups – patients with COPD and patients with COPD and CKD, according to the estimated glomerular filtration rate (eGFR) indicator. A correlation was sought between vitamin D levels and chronic kidney disease (CKD) in patients with COPD. The data were processed using the statistical software SPSS, version 20.0. A p < 0.05 was considered statistically significant. Results: At the first visit, 70% of patients had low vitamin D levels and 42.2% had both COPD and CKD. At the second visit, 97.4% were vitamin D deficient and 52.6% had CKD. A statistically significant difference was found regarding vitamin D deficiency between the two groups. In the group with eGFR < 60 mL/min/1.73 m², 54% of cases had low vitamin D levels (p = 0.0007). We established a cutoff value of 16.98 ng/mL and agreement between vitamin D and eGFR (AUC) of 41%, Gini index -0.173, sensitivity 79%, and specificity 25%. During dynamic follow-up of vitamin D levels, we found a statistically significant difference between the values at the two visits (p < 0.01) and between the two groups (p = 0.012). Conclusion: Patients with COPD frequently suffer from vitamin D deficiency, which is more pronounced in those with both COPD and CKD.