AGE-ASSOCIATED ENDOCRINE DEFICIENCIES AS POTENTIAL DETERMINANTS OF FEMORAL-NECK (TYPE-II) OSTEOPOROTIC FRACTURE OCCURRENCE IN ELDERLY MEN

Osteoporotic fractures, and especially hip fractures, are a leading ca use of morbidity and mortality among elderly men. Among other factors, a decline in bone mass has been identified as the major determinant o f the age-related reduction in bone strength and therefore of osteopor otic fracture risk. Recent evidence suggests that age-associated endoc rine deficiencies may contribute to femoral bone loss and hip fracture occurrence in elderly men. The decline in circulating androgen levels and the decreased activity of the growth hormone-insulin-like growth factor-I axis may result in a reduction in bone formation that contrib utes to the age-related increase in bone fragility in men. Vitamin D d eficiency-induced secondary hyperparathyroidism, on the other hand, ma y further enhance bone loss by activating bone turnover and so increas ing the number of bone remodelling units with impaired bone formation. On the basis of these pathophysiological models, guidelines can be de veloped for the prevention of age-related bone loss in men, but these approaches lack validation. The results of controlled intervention tri als will have to be awaited to answer the question of whether hormone replacement therapy attenuates bone loss and reduces fracture incidenc e in elderly men.