The aim was to study the association between 25-hydroxyvitamin D [ 25(OH)D ] levels and the clinical characteristics of patients with chronic inflammatory rheumatic diseases ( CIRD ).
Researchers studied a cross-section from the baseline visit of the CARMA project ( CARdiovascular in rheuMAtology ), a 10-year prospective study evaluating the risk of cardiovascular events in rheumatoid arthritis ( RA ), ankylosing spondylitis ( AS ) and psoriatic arthritis ( PsA ) patients, and non-CIRD patients who attended rheumatology outpatient clinics from 67 hospitals in Spain.
Non-CIRD group was frequency matched by age with the joint distribution of the three CIRD groups included in the study.
25(OH)D deficiency was defined if 25(OH)D vitamin levels were
2.234 patients ( 775 rheumatoid arthritis, 738 ankylosing spondylitis and 721 psoriatic arthritis ) and 677 non-CIRD subjects were assessed.
The median ( p25-p75 ) 25(OH)D levels were: 20.4 ( 14.4-29.2 ) ng/ml in rheumatoid arthritis, 20.9 ( 13.1-29.0 ) in ankylosing spondylitis, 20.0 ( 14.0-28.8 ) in psoriatic arthritis, and 24.8 ( 18.4-32.6 ) ng/ml in non-CIRD patients.
Researchers detected 25(OH)D deficiency in 40.5% rheumatoid arthritis, 39.7% ankylosing spondylitis, 40.9% psoriatic arthritis and 26.7% non-CIRD controls ( p less than 0.001 ).
A statistically significant positive association between rheumatoid arthritis and 25(OH)D deficiency was found ( adjusted OR = 1.46; 95 % CI = 1.09-1.96 ); p = 0.012.
This positive association did not reach statistical significance for ankylosing spondylitis ( adjusted OR 1.23; 95 % CI = 0.85-1.80 ) and psoriatic arthritis ( adjusted OR 1.32; 95 % CI = 0.94-1.84 ).
When the parameters of disease activity, severity or functional impairment were assessed, a marginally significant association between 25(OH)D deficiency and ACPA positivity in patients with rheumatoid arthritis ( adjusted OR = 1.45; 95 % CI = 0.99-2.12; p = 0.056 ), and between 25(OH)D deficiency and BASFI in patients with ankylosing spondylitis ( adjusted OR = 1.08; 95 % CI = 0.99-1.17; p = 0.07 ) was also found.
In conclusion, patients with rheumatoid arthritis show an increased risk of having 25(OH)D deficiency compared to non-CIRD controls. ( Xagena )
Urruticoechea-Arana A et al, Arthritis Res Ther 2015;17:211. doi: 10.1186/s13075-015-0704-4.