Systemic sclerosis and bone loss: the role of the disease and body composition.

OBJECTIVES: Studies on body composition are not available in systemic sclerosis (SSc). As this variable may play an important role in bone loss we have analysed bone mineral density (BMD) and body composition in SSc patients and healthy controls. METHODS: Forty-three postmenopausal SSc patients and 47 healthy postmenopausal women were studied. Patients with intestinal malabsorption, renal failure, current or past history of smoking or using osteopenic drugs were excluded. BMD and body composition was evaluated by dual X-ray absorptiometry (DXA). RESULTS: A higher frequency of osteoporosis in the lumbar spine (32.5%) and femoral neck (51.1%) was observed in SSc patients when compared to controls (14.8% vs. 19.1%; p<0.01). Multiple linear regression analysis revealed an association between the presence of SSc and low BMD. Body composition showed a reduced lean mass (33.15 vs. 39.99 g; p<0.01) and fat mass (21.05 vs. 26.82 g; p<0.01) in SSc when compared to controls. Lean mass was an important factor related to BMD in the lumbar spine and femoral neck. CONCLUSION: SSc may be an independent factor for low BMD. The low lean mass in these patients emphasizes the need for appropriate additional therapeutic measures to reduce bone loss in SSc patients.