Prevalence of Vitamin D Insufficiency/Deficiency in Rheumatoid Arthritis and Associations with Disease Severity and Activity

Objective. 25-hydroxy-vitamin D (25-OH-D) insufficiency/deficiency is increasingly prevalent and has been associated with many chronic diseases, including rheumatoid arthritis (RA). Our purpose was to define the prevalence and associations of 25-OH-D insufficiency/deficiency in a cohort of US veterans with RA. Methods. Vitamin D status (25-OH-D) was assessed in patients with RA using radioimmunoassay on banked plasma collected at enrollment. Insufficiency was defined as concentrations < 30 ng/ml and deficiency as < 20 ng/ml. Associations of 25-OH-D insufficiency/deficiency with patient characteristics obtained at enrollment were examined using multivariate logistic regression, adjusting for age, sex, season of enrollment, and race. Results. Patients (850 men, 76% Caucasian) had a mean (SD) age of 64 (SD 11.3) years. The prevalences of 25-OH-D insufficiency and deficiency were 84% and 43%, respectively. After multivariate adjustment, both insufficiency and deficiency were more common with anti-cyclic citrullinated peptide antibody positivity and non-Caucasian race, and in the absence of vitamin D supplementation. 25-OH-D deficiency, but not insufficiency, was independently associated with higher tender joint counts and highly sensitive C-reactive protein levels. Conclusion. In a predominantly elderly, male RA population, 25-OH-D insufficiency was highly prevalent. With the increasing adverse health outcomes associated with hypovitaminosis D, screening and supplementation, particularly among minority, seropositive patients with RA, should be performed routinely. (First Release Oct 15 2010; J Rheumatol 2011;38:53-9; doi:10.3899/jrheum.100516)