Significance of Vitamin D Deficiency in Rheumatoid Arthritis; Relation to Disease Severity and Activity, MERVAT M. ABO GABAL, SAMAH A. EL BAKRY, SAMEH A. HASSAN, NOHA H. AHMED, FATMA M. ABOUD and HOSSAM M. SAKR
Abstract
Objective: To estimate serum level of active vitamin D in patients with rheumatoid arthritis and to assess the impact of vitamin D deficiency on disease severity and activity.
Methods: Pilot study included 35 rheumatoid arthritis patients in the first 2 years of disease onset compared with 30 healthy age and sex matched controls. Assessment of serum vitamin D level was done at baseline for both patients and controls, accordingly patients were classified as group I (with vitamin D deficiency) and group II (with vitamin D insuffi-ciency). At baseline, patients were subjected to full history taking, clinical examination with assessment of disease activity and functional ability, complete blood picture, liver enzymes, kidney functions and rheumatoid factor (IgM). Follow-up every three months for one year was done for rheumatoid patients. Each time reassessment using DAS28 score, Eryth-rocyte sedimentation rate (ESR) and quantitative C-reactive protein (CRP) titer for activity and Health Assessment Ques-tionnaire (HAQ) score for functional ability. Assessment of disease severity was done at baseline and after one year using the Larsen score.
Results: There was statistically significant higher frequen-cy of vitamin D deficiency in RA patients (62.86%) compared to controls (13.34%), non of RA patients had normal vitamin D level versus 13 (43.33%) in controls. The mean serum vitamin D level was significantly lower in RA patients than controls. At baseline, vitamin D deficiency was associated with higher HAQ score, number of tender and swollen joints, DAS28 score, and frequency of severe activity, ESR and CRP titer, Larsen score and frequency of erosions. Serum vitamin D level was negatively correlated with these parameters. At the end of one year follow-up there was significant higher frequency of patients with moderate disease activity, lower frequency of remission, more radiographic damage and ero-sions in the deficient patients.
Conclusion: Vitamin D deficiency is common in the RA patients. Patients with vitamin D deficiency have more disease activity, functional disability, more joint damage and less response to therapy. Baseline vitamin D level may have a prognostic value in patients with RA.