title: Relationship between disease activity and serum levels of vitamin D metabolites and PTH in rheumatoid arthritis.
abstract: In several studies on patients with rheumatoid arthritis, an association of bone loss with a persistently high disease activity has been found. The aim of our study was to investigate the relation between disease activity and serum levels of vitamin D metabolites, parathyroid hormone (PTH), and parameters of bone turnover in patients with rheumatoid arthritis. A total of 96 patients (83 women and 13 men) were divided into three groups according to disease activity measured by serum levels of C-reactive protein (CRP). In the whole group, serum levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (P < 0.001) and PTH (P < 0.05) were negatively correlated to disease activity. The urinary excretion of collagen crosslinks--pyridinoline (Pyd) (P < 0.001) and deoxypyridinoline (Dpd) (P < 0.05)--showed a positive correlation with disease activity. The inverse correlation between serum 1,25(OH)2D3 and disease activity was separately evident in patients with (P < 0.001) and without (P < 0.01) glucocorticoid treatment, in pre- (P < 0.01) and postmenopausal (P < 0.001) women, and in men (P < 0.01). 1,25(OH)2D3 and PTH serum levels were positively correlated to serum bone alkaline phosphatase (ALP) (P < 0.01). The results indicate that high disease activity in patients with rheumatoid arthritis is associated with an alteration in vitamin D metabolism and increased bone resorption. The decrease of 1,25(OH)2D3 levels in these patients may contribute to a negative calcium balance and inhibition of bone formation. Furthermore, low levels of 1,25(OH)2D3 as an endogenous immunomodulator suppressing activated T cells and the proliferation of cells may accelerate the arthritic process in rheumatoid arthritis.
authors.affiliation: Department of Internal Medicine IV, Friedrich Schiller University of Jena, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Oelzner
authors.forename: A
authors.initials: A
authors.lastname: Müller
authors.forename: F
authors.initials: F
authors.lastname: Deschner
authors.forename: M
authors.initials: M
authors.lastname: Hüller
authors.forename: K
authors.initials: K
authors.lastname: Abendroth
authors.forename: G
authors.initials: G
authors.lastname: Hein
authors.forename: G
authors.initials: G
authors.lastname: Stein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D015415:Biomarkers / Q000097:blood; D001851:Bone Diseases, Metabolic / Q000097:blood*; D016723:Bone Remodeling / Q000502:physiology; D002097:C-Reactive Protein / Q000378:metabolism; D002112:Calcifediol / Q000097:blood*; D002117:Calcitriol / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D011859:Radiography
chemical_list: D015415:Biomarkers; D010281:Parathyroid Hormone; D002097:C-Reactive Protein; D002117:Calcitriol; D002112:Calcifediol