ASSESSMENT OF BONE DENSITY IN WOMEN WITH SYSTEMIC SCLERODERMA AND ITS RELATIONSHIPS WITH DISEASE PARAMETERS AND VITAMIN D STATUS

Y. Ibn Yacoub, B. Amine, A. Laatiris, F. Wafki, F. Znat, N. Hajjaj-HassouniEl Ayachi Hospital, Sale, Morocco Rheumatology, El Ayachi Hospital, Sale, MoroccoObjectives: Our first objective was to evaluate the bone mineral density (BMD) in Moroccan women with SSc, in the absence of confounding variables that interfere with bone metabolism, in a case-control study. Our second objective was to assess the 25-hydroxyvitamin D3 status and its relationships with disease activity, severity and with BMD. Methods: Sixty patients with SSc and 60 age and gender matched healthy controls were included. Following data were collected in patients and controls: Body mass index, menopausal status, familial history of osteoporosis and/or fractures; personal fracture history; exercise activity and laboratory parameters of bone metabolism. A dual energy X-ray absorptiometry was used to measure BMD in lumbar spine (L1-L4) and femoral neck. The 25-hydroxyvitamin D3 was measured in a subgroup of 30 patients and in a subgroup of 30 matched controls. In the patients' group, we assessed systemic manifestations, biological inflammatory parameters, functional disability (scleroderma health assessment questionnaire (S-HAQ)) and immunological status of disease. Differences between patients and controls were assessed by using a T test for continuous variables. In patients' group, correlations were performed with Pearson correlation coefficient completed with regression models for significant variables. Results: The mean age of patients was 49.34±13.07 years vs. 49.76±12.11 in controls. SSc patients had a significantly earlier age and longer duration of menopause than controls (p=0.003). Phosphocalcic metabolism parameters were within normal ranges in both groups. BMD was significantly lower in SSc patients than in controls both in lumbar spine [-2.97±0.25 in patients vs. 0.46±0.11 in controls] and femoral neck [-1.93±0.32 in patients vs. -0.81±0.69 in controls] (p<0.01). Thirty-six (60%) patients vs. 15 (25%) controls had osteoporosis and 19 (31.7%) patients vs. 13 (21.7%) controls had osteopenia (p<0.01). In correlations and in multiple regression models, decreased BMD (in lumbar spine and femoral neck) were correlated with prolonged disease duration, severe joint involvement (severe joint pain and erosive arthropathy), malabsorption syndrome and the positivity of anti DNA topoisomerase I antibodies (for all p≤0.01). On the other hand, patients had lower levels of vitamin D (10.88±2.68 ng/ml) comparing to controls (57.41±4.18 ng/ml) (p=0.001). Low levels of vitamin D were associated with severe joint pain (β=-0.769; p=0.006), immunological status (anti DNA topoisomerase I antibodies) (β =-0.299; p=0.027) and with BMD in lumbar spine (β=0.436; p=0.002) and femoral neck (β=0.436; p=0.032). Conclusions: In our study, we state the importance of bone loss in Moroccan women with SSc comparing to healthy controls. Decreased BMD seems to be associated with prolonged disease duration, severe joint involvement, malabsorption syndrome and immunological status. Also, SSc patients had very low levels of 25-hydroxyvitamin D3 than controls. Larger studies are needed to assess interactions between vitamin D systems; disease activity and bone loss in SSc. Disclosure of Interest: None DeclaredCitation: Annals of the Rheumatic Diseases, volume 70, supplement 3, year 2011, page 669Session: Scleroderma, Myositis and related syndromes (Poster Presentations )