Jelsness-Jorgensen LP, et al. - A cross-sectional study was performed to investigate relationships between fatigue and vitamin D status in patients with rheumatoid arthritis (RA). Researchers recruited a total of 169 individuals with established RA. Fatigue, evaluated by the Chalder fatigue questionnaire, and serum liquid chromatography-tandem mass spectrometry estimated concentrations of 25-hydroxyvitamin D (25(OH)D). Associations were investigated by relationship, and multivariate linear regression with adjustments for age, gender, BMI, RA disease activity as estimated by the Disease Activity Score 28-joint count C reactive protein, psychological distress, pain, and sleep. There was no association between vitamin D and fatigue in individuals with RA in this cross-sectional study.