No abstract

Although additional fracture data are needed to endorse the clinical care of osteoporosis in men, consensus views were reached on diagnostic criteria and intervention thresholds. Empirical data in men display similarities with data acquired in women, despite pathophysiological differences, which may not be clinically relevant. Men should receive treatment at a similar 10-year fracture probability as in women. The design of mixed studies may reduce the lag between comparable treatments for osteoporosis in women becoming available in men.

To address the issue whether deficient acquisition of bone during maturation or adult-onset bone loss is primarily to blame for idiopathic osteoporosis in men, we assessed indices of bone mineral density and size, as well as biochemical markers of bone turnover in 61 probands (ages 20 -65 years) with idiopathic osteoporosis (z-score < ؊2.0 at the spine or hip), their first-degree relatives (n ‫؍‬ 130), and age-matched controls. There was no indication of accelerated bone loss. Indeed, in probands, the observed bone deficit versus controls was unrelated to the age of probands, and indices of bone turnover were not significantly different from controls. On the other hand, a specific deficit in bone acquisition was suggested by findings of lower bone mineral density values in three generations of male and female relatives of the probands, including their offspring; bone turnover in relatives was not different from controls. The bone mineral density deficit was more pronounced in male compared with female relatives; approximately 60% of the sons had a spinal bone mineral density z-score of less than ؊2.0. There also was a skeletal site-specificity in probands and their male relatives with a larger areal bone mineral density deficit at the spine compared with the hip and the forearm. The deficit at the spine corresponded to a reduction of both volumetric bone mineral density and bone size; a similar less pronounced deficit in volumetric bone mineral density, but not in bone size, was observed at the femoral neck. These findings in probands and their first-degree relatives point toward a major contributory role of a genetically determined maturational defect in bone acquisition in the pathogenesis of idiopathic osteoporosis in men. (J Bone Miner Res 2003;18:303-311)

The FRAX® tool has been used to identify possible thresholds for therapeutic intervention in Belgium, based on equivalence of risk with current guidelines. The FRAX® model supports a shift from the current DXA-based intervention strategy, towards a strategy based on fracture probability of a major osteoporotic fracture that in turn may improve identification of patients at increased fracture risk. The approach will need to be supported by health economic analyses.

The aim of the present study was to determine the variations in the balance between total (free plus combined) circulating alpha and beta subunits of human chorionic gonadotrophin (hCG) throughout human pregnancy. The equivalence between the International Units (IU) of hCG (IRP 75/537) and those assigned to the alpha (IRP 75/569) and beta (IRP 75/551) free subunits was experimentally determined by using intact and thermally dissociated hCG. Heat exposure (2 min at 100 degrees C) of hCG preparations resulted in a complete dissociation of hCG into free, soluble and intact alpha and beta subunits. The hCG and alpha and beta subunit contents of unaltered and heated hCG preparations were assessed by specific immunoradiometric assays. The amount of immunoreactive subunits dissociated by heat from hCG could then be evaluated on a molar basis. Circulating hCG and its free alpha and beta subunits were immunoassayed in 836 blood samples collected from healthy pregnant women at different gestational ages. After conversion of hCG and its subunits into a common IU system, the gestational profiles of the total amounts (free plus combined) of alpha- and beta hCG subunits increased together and peaked at 9-10 weeks of gestation. Thereafter, total alpha and beta subunits decreased and subsequently remained stable until term. The decline in total alpha hCG subunit was less marked than that of total beta hCG subunit. The alpha- to beta hCG ratio was equimolar until 10 weeks of gestation when it increased almost fourfold until term (P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)