The determinants of fracture in men.

Osteoporosis represents an increasingly important clinical and public health problem among older men. Estimates indicated that 1-2 million (3-6%) men aged 50 years and over in the United States have osteoporosis and 8-13 million (28- 47%) have osteopenia. The lifetime risk of suffering a hip, spine or forearm fracture for a 50-year-old man is 13%, similar to the risk for prostate cancer. The number of osteoporotic fractures in men is expected to increase dramatically due to aging of the population and secular increases in fracture rates. Identification of men who are at greatest risk of osteoporosis and the risk factors, which predispose men to fracture, are essential so that preventive steps can be taken. Data on risk factors are emerging but many questions remain. Men may fracture at a higher bone mineral density (BMD) level than women. However, estimates of volumetric BMD, which correct in part for gender differences in bone size, and risk of fracture, may actually show similar relationships in men and women. Fracture rates are similar in older African American women and Caucasian men. Improved understanding of ethnic differences in fracture could identify potential reasons for gender differences. Family history and genetic factors are also important risk factors for fractures but the specific candidate genes are not known and whether gender modifies the effects of these genetic polymorphisms on BMD and the risk of fracture is also not known. In general, lifestyle factors and anthropometric measurements show similar relationships with fractures in men and women although few comprehensive prospective studies have been conducted. Current data will be reviewed on the relationships between markers of skeletal health, genetic polymorphisms, lifestyle and anthropometric factors and fracture.