Clinical determinants of bone mass and bone ultrasonometry in patients with systemic sclerosis

OBJECTIVE: The aim of this study was to evaluate bone mass and bone ultrasonometry in patients affected with systemic sclerosis (SSc). METHODS: Fifty-five patients (mean age 54.1 +/- 14.1 years; 25 premenopausal, and 30 postmenopausal women) affected with SSc (in a limited, intermediate or diffused form) and 60 age-matched healthy controls (30 premenopausal, and 30 postmenopausal women) were studied for Bone Mineral Density (BMD) measured by fan-beam x-ray densitometry, Stiffness Index (SI) measured by ultrasonometry of the heel, inflammation indices (erithrocyte sedimentation rate, C-reactive protein), and autoantibodies (ANA, ENA). Examinations were also carried out in order to determine any internal organ involvement. None of the patients had previously received steroid treatment. RESULTS: BMD was significantly lower in the SSc group than in the control group, whether it was expressed in g/cm2 (lumbar spine: 0.980 vs 1.241, p < 0.01; femoral neck: 0.832 vs 0.955, p < 0.05; total body 1.050 vs 1.168, p < 0.01) or by T- and Z-score (lumbar spine: T = -2.48; Z = -1.10; femoral neck: T = -1.69; Z = -0.55; total body: T = -1.11; Z = -0.48). SI was also altered (75.8 vs 96.2, p < 0.01; T = -2.10, Z = -1.12). BMD and SI were lower in women with the diffuse form of skin involvement. BMD and SI were lower in women in whom one or more internal organs were involved. CONCLUSION: SSc patients had reduced BMD and SI that was more marked in the diffuse form and in those with internal organ involvement and that became more marked with age and estrogen deficiency. This demineralisation was not related to the inflammation indices, disease duration, or to the immunological pattern.