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

B. Frediani, F. Baldi, P. Falsetti, C. Acciai, G. Filippou, A. Spreafico, C. Siagri, F. Chellini, C. Capperucci, P. Filipponi1, M. Galeazzi, R. Marcolongo

Institute of Rheumatology, University of Siena, Siena; 1Bone and Mineral Research Unit, University of Perugia, Perugia, Italy.

ABSTRACT
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.

Key words
Osteoporosis, systemic sclerosis, dual x-ray absorptiometry, quantitative ultrasound.


Please address correspondence to: Bruno Frediani, MD, Institute of Rheumatology, Policlinico "Le Scotte", Viale Bracci 1, 53100 Siena, Italy. 
E-mail: fredianibruno@tiscalinet.it

Clin Exp Rheumatol 2004; 22: 313-318.
© Copyright Clinical and Experimental Rheumatology 2004.