Osteoporosis affects about 4.7 million people in Italy and leads to over 300,000 bone fractures per year. In view of this, and in order to implement preventive strategies to reduce the burden of fractures in Southern Apulia, the PROF (Prevention of Osteoporotic Fractures) project was launched, based on the synergistic efforts of academic/scientifìc and healthcare institutions.
Within PROF, a computerised registry was set up, gathering demographic and anamnestic data on patients, such as body mass index (BMI), information about dietary habits, menopause, physical activity, previous fractures, familial fragility fractures, and other clinical/instrumental parameters deemed able to identify, early on, patients at higher risk of fractures. The aim of the present analysis was to investigate the correlation between low BMI (<20) and osteopenic/osteoporotic status in postmenopausal women tested by bone quantitative ultrasound (QUS) examination.
5665 postmenopausal women (mean age 55, range from 39 to 84) were screened non-invasively by QUS examination at the heel and/or phalanx. Three mineralisation categories were identified: a) Demineralisation, when any T-score <−1.0 SD was observed; b) Severe demineralisation, whenever a T-score <−2.0 was observed, corresponding to a higher risk of fracture; c) Osteoporosis, in the presence of a QUS T-score <−2.5±0.2 (for the heel) or a T-score <− 3.2±0.2 (for the phalanx).
Demineralisation of various degrees was observed in 4487 cases (79%), with 1178 (21%) of all the examined subjects found to have normal parameters. Of the 4487 cases with demineralisation, 144 were postmenopausal women with a BMI <20. On QUS testing, only 20 of these (14%) showed a status around normal, while 84 had either an osteopenic or severe demineralisation status (58%) and 32 women were found to be frankly osteoporotic.
These data confirm that a low BMI (<20) is a clear indicator of demineralisation status in postmenopausal women, and almost doubles the risk of a frank and dangerous osteoporotic status. As a matter of fact, only 10% of postmenopausal women with low BMI had normal QUS examinations, at either heel or phalanx level. Therefore, in clinical terms, a low BMI in menopausal women signals the need to undertake pro-active measures and clinical monitoring in order to implement strategies to increase bone mineral density.