INVESTIGADORES
COINTRY Gustavo Roberto
congresos y reuniones científicas
Título:
Gender-related differences and post-menopausal changes in the cross-sectional distribution of pQCT assessed vBMD of radial and tibial diaphyseal bone in healthy adults
Autor/es:
GUSTAVO ROBERTO COINTRY; RICARDO FRANCISCO CAPOZZA; SARA FELDMAN; NÉSTOR MATÍAS FRACALOSSI; SEBASTIÁN FERRETTI; PAOLA REINA; MARÍA VICTORIA FERRETTI; MARÍA CAROLINA FERULLO; GABRIELA MARCHETTI; JOSÉ LUIS FERRETTI
Lugar:
Ginebra (Suiza)
Reunión:
Congreso; II Joint Meeting, International Bone & Mineral Society (IBMS) - European Calcified Tissue Society (ECTS); 2005
Institución organizadora:
International Bone & Mineral Society
Resumen:
To describe the gender-related differences and the influence of menopause (MP) on the distribution of previously defined regions of interest (ROIs) with high, medium or low values of diaphyseal vBMD (pixels with attenuation coefficient values >1.0 cm-1, HD; 0.4-1.0 cm-1, MD; and <0.4 cm-1, LD, respectively) in healthy men and pre- and post-MP women (n = 40, 60, 100) in pQCT scans of the sites 66% proximal to the wrist and ankle joints in the left radii and tibiae.Results: Results were generally coherent for radii and tibiae. The percentage distribution of HD, MD and LD pixel areas was similar in men and pre-MP women. The HD area was lower and the MD area was higher in post-MP than pre-MP women. The LD area showed little inter-group and post-MP variation. The HD area decreased proportionally to the years elapsed since MP (YSMP). A single, negative-exponential relationship between the percentual HD (y) and MD (x) areas of all the studied bones, showed characteristic distribution zones, showing decaying values of the HD/MD relationship in the order: men > pre-MP women > post-MP women with up to 7 (forearm) or 9 (leg) YSMP > post-MP women with more YSMP. The post-MP loss of HD area determined also a loss of geometrical continuity of the HD ROI.Interpretation. pQCT allows for an interesting, qualitative and quantitative structural-biomechanical analysis of the volumetric density distribution of diaphyseal bone in men and women. Quantitatively, the proportion between the percentual HD and MD areas, similar in males and fertile females, decayed in the women with time since MP. Qualitatively, the post-MP loss of HD area (representing the relative amount of the stiffest and strongest cortical tissue) determined also a geometrical discontinuity of the respective ROI in the cross section, which may have severe mechanical consequences. Congruence of results in forearm and leg suggest little or no influence of gravity on this aspect of skeletal physiology. The interdependence between the percentual HD and MD areas was reflected by the negative relationships observed between those variables in both forearms and legs when all bones were studied together. These curves provide reference charts suitable for evaluating the relative deterioration of the structure and mechanical ability of cortical bone (shifts toward the lower-right region of the graphs) in men and women in clinical studies, beyond the DEXA scope.