Osteoporosis in men: prevalence and investigation

In the past, osteoporosis was thought to affect only women; however, in the last decade it has become apparent that osteoporosis is common in men, particularly elderly men. Osteoporosis affects as many as 2 million men in the United States. Osteoporosis most commonly affects the hip and the lumbar vertebrae, but other bones, such as the radius, tibia, and ribs, may also fracture. The main feature of the etiology of the disease is that low bone mineral density results in increased susceptibility to bone fracture. The World Health Organization has defined osteoporosis as a bone mineral density T-score value >2.5 SDs below the mean observed in young adult women. Although the validity of this score for evaluating men has been questioned and it is not clear whether a male or female reference database should be used, it is nonetheless often used in this way. The disease affects men differently than women in a number of respects. It manifests itself later in life in men than in women, probably because men initially have greater bone mass. Mortality and morbidity associated with hip fractures are high in all elderly individuals, but they are substantially higher in men than in women. Unlike in women, there is an underlying cause for the osteoporosis in almost half of affected men. Thus, for elderly men, a complete history and physical examination may reveal some remediable conditions; treating these may stop further progression of the disease and prevent further morbidity or mortality. Corticosteroid therapy for arthritis or asthma is a common cause of osteoporosis in elderly men. Hypogonadism is a recognized cause of osteoporosis in men treated for carcinoma of the prostate with androgen withdrawal therapy; treatments to modify the effects of these agents on bone are available. Consumption of large amounts of alcohol will eventually result in osteoporosis in some elderly men. Moreover, alcohol can predispose confused elderly patients to falls and to fracture bones that are already osteoporotic. Hyperthyroidism is associated with a reduction in bone mineral density and an increased likelihood of bony fracture. A careful search for undiagnosed hyperthyroidism in elderly osteoporotic men may prove worthwhile. Vitamin D deficiency is common among older men and could contribute to an increase in fractures. Routine analyses of blood and biochemistry should be carried out in any older male patient with newly diagnosed osteoporosis. Dual x-ray energy absorptiometry should be performed on every new patient with newly diagnosed osteoporosis.