[Cortical bone mass and risk factors for osteoporosis among postmenopausal women in our environment]

To evaluate the relevance of the so called risk factors for osteoporosis among women.

A total of 150 consecutive postmenopausal women who had been enrolled in the gynecology outpatient clinics of the Health Areas affiliated to the Alcalá de Henares University Hospital. Bone mass of these women was calculated as index of metacarpal cortical area/total area (CA/TA) (mm2), measured by radiogrammetry.

With the ANOVA test, a late menarchial age and a shorter reproductive life induced a lower bone mass (p < 0.0005 and < 0.05, respectively); also, a history of bone fractures without previous relevant trauma (p < 0.05) was obtained. By correlational studies, there was a negative significance between CA/TA index and chronological age, menarchial age, menopausal age and number of fractures (r = -0.20 to -0.30; p < 0.05 to < 0.0001) and a positive significance with years of reproductive life (r = 0.17; p < 0.05). These values virtually remain unchanged when with partial correlation are weight adjusted, but with the multiple regression model, the CA/TA index is negatively significant only with menopause years (p < 0.005). Taking the average of the metacarpal CA/TA index as value, a sensitivity of 50% and an specificity of 78% were obtained to indicate fractures and a negative predictive value of 92%.

These results indicate the greater importance of menarchial age, of reproductive life years and therefore of menopausal years, as determinants of postmenopausal bone mass and show a very acceptable specificity of the CA/TA index as predictive for bone fracture.