Association between Vitamin D Deficiency and Carotid Intima-media Thickness in Patients with Rheumatoid Arthritis

Abstract

Objective. The present study determined if vitamin D deficiency is a potential risk factor for increased carotid intima-media thickness (CIMT) in patients with rheumatoid arthritis (RA). Methods. This cross-sectional study analyzed 50 consecutive female RA patients without cardiovascular disease history at the Pusan National University Hospital between September and December of 2013. CIMT was measured using a high-resolution ultrasonography. Serum 25-hydroxy vitamin D (25-OHD) levels were assessed by radioimmunoassay, and vitamin D deficiency was defined as serum 25-OHD levels <20 ng/mL. Stepwise multivariable linear regression analyses were performed to evaluate the association between vitamin D deficiency and increased CIMT. Results. The median 25-OHD level (inter-quartile range) was 14.0 (11.0∼20.7) ng/mL, and 74% of patients had vitamin D deficiency. The mean±standard deviation of CIMT was 0.58±0.08 mm. RA patients with vitamin D deficiency had significantly higher CIMT than those without this feature (0.59±0.07 vs 0.54±0.05, p=0.028). In univariable linear regression models, vitamin D deficiency (β(SE)=0.047 (0.021), p=0.028), older age (β(SE)=0.003 (7.2), p<0.001) and higher disease activity score 28-erythrocyte sedimentation rate (β(SE)=0.021 (0.010), p=0.034) and Korean version of health assessment questionnaire score (β(SE)=0.051 (0.015), p=0.002) were significantly associated with increased CIMT. Vitamin D deficiency remained statistically significant in multivariable regression models after adjusting for confounders. Conclusion. Vitamin D deficiency was associated with increased CIMT in female RA patients. Our finding suggests that hypovitaminosis D can be a risk factor for atherosclerosis in RA patients.