Transmenopausal change of trabecular bone density and structural pattern assessed by peripheral quantitative computed...

Trabecular bone pattern, related to connectivity, was analyzed along with a separate measurement of cortical and trabecular bone mineral density (BMD) at the distal radius by peripheral quantitative computed tomography (pQCT) in 48 perimenopausal women, consisting of 25 premenopausal women aged 41 to 52 (mean 46.6 +/- 2.9 years) and 23 early postmenopausal women aged 46 to 59 (mean 53.2 +/- 3.2 years) within 5 years of the menopause (mean 2.7 +/- 1.5 years). No significant difference was found in either cortical or trabecular bone density between premenopausal and postmenopausal women despite a significant difference in age (premenopause vs postmenopausal: 46.7 +/- 2.9 years vs 53.2 +/- 3.1 years, p < 0.00001), including a slow change of BMD, if any, before and within 5 years of the menopause. However, analysis of trabecular fragments and perforation revealed a significant increase of the number of perforations in postmenopausal compared with premenopausal women (premenopausal vs postmenopausal: 0.9 +/- 1.6 vs 2.9 +/- 2.3, p < 0.002), indicating that disconnectivity has already increased before a significant reduction of BMD. Furthermore, chi-square analysis showed that even postmenopausal women with trabecular BMD more than 160 mg/cm3 were about 11 times more likely to have three or more perforations than premenopausal ones (odds ratio: 11.42, F = 0.030). These data suggest that trabecular bone connectivity is more sensitive that BMD in the detection of the early changes of postmenopausal osteoporosis.