Relationship of Serum Vitamin D Concentrations with Inflammatory Biomarkers in Adults

Open Access

Abstract

Background: Vitamin D deficiency is prevalent in Bangladesh, and vitamin D is hypothesized to influence immune and inflammatory pathways in addition to its established role in bone health. This study aimed to examine the association between serum 25-hydroxyvitamin D and commonly measured inflammatory markers among adults. Methods & Materials: This analytical cross-sectional study (2023 to 2024) at NITOR and NIKDU, Dhaka, Bangladesh consecutively enrolled adults aged at least 18 years (n=184), excluding pregnancy, recent infection, major inflammatory or autoimmune disease, malignancy, advanced liver or kidney disease, high-dose vitamin D therapy, or immunosuppressant use. Serum 25(OH)D and routine inflammatory markers (hsCRP, ESR, albumin, uric acid, and CBC-derived NLR, PLR) were measured, with lifestyle and seasonality data recorded, and associations analyzed using correlation and adjusted linear regression in SPSS v26. Results: Among 184 adults (mean age 41.6 years; mean BMI 25.1 kg/m²), mean serum 25(OH)D was 19.4 ± 7.6 ng/mL, with 62% deficient, 25% insufficient, and 13% sufficient. Inflammatory burden was higher in vitamin D deficiency compared with sufficiency, including hsCRP, ESR, NLR, and PLR, while albumin was lower (all p≤0.041). Serum 25(OH)D correlated inversely with hsCRP, ESR, NLR, PLR, and positively with albumin (all p≤0.030). In adjusted models, each 10 ng/mL increase in 25(OH)D was associated with lower ln(hsCRP) (β = -0.18), lower ESR (β = -2.6 mm/hr), lower ln (NLR) (β = -0.12), and higher albumin (β = +0.07 g/dL). Conclusion: Vitamin D deficiency was common in this adult cohort, and lower serum 25(OH)D was independently associated with higher hsCRP, ESR, and NLR, and lower albumin.