DefinePK

Abstract

Background: Vitamin D is a fat-soluble secosteroid that plays an essential role in calcium homeostasis and skeletal health. Recent findings have also linked vitamin D to immune modulation and inflammatory regulation in endocrine dysfunctions. Chronic endocrine disorders such as Type 2 Diabetes Mellitus (T2DM), Polycystic Ovary Syndrome (PCOS), and hypothyroidism often exhibit persistent low-grade systemic inflammation, which may be exacerbated by vitamin D deficiency.
Objective: To assess the relationship between serum vitamin D levels and systemic inflammatory markers in patients diagnosed with T2DM, PCOS, and hypothyroidism.
Methods: A cross-sectional study was conducted at a tertiary healthcare center between January and June 2024, including 120 patients aged 25–50 years with a clinical diagnosis of T2DM, PCOS, or hypothyroidism. Participants were categorized into three groups based on serum 25-hydroxyvitamin D [25(OH)D] levels: deficient (<20 ng/mL), insufficient (20–30 ng/mL), and sufficient (>30 ng/mL). Inflammatory markers including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and neutrophil-to-lymphocyte ratio (NLR) were measured. Data were analyzed using one-way ANOVA for group comparisons and Pearson correlation to assess associations, with p-values <0.05 considered statistically significant.
Results: CRP (12.5 ± 5.4 vs. 5.6 ± 2.3 mg/L; p = 0.01), ESR (40.5 ± 17.6 vs. 27.6 ± 10.1 mm/h; p = 0.03), and NLR (4.1 ± 1.4 vs. 2.9 ± 1.0; p = 0.02) were significantly higher in vitamin D-deficient patients compared to those with sufficient levels. Strong negative correlations were noted between 25(OH)D and CRP (r = –0.46, p < 0.01), ESR (r = –0.40, p = 0.01), and NLR (r = –0.41, p = 0.01), particularly in PCOS patients where NLR had the strongest inverse correlation (r = –0.41, p < 0.01).
Conclusion: Vitamin D deficiency is significantly associated with elevated systemic inflammatory markers across T2DM, PCOS, and hypothyroidism. Routine screening and correction of vitamin D status may aid in mitigating inflammation in these endocrine disorders.