Race/ethnicity in relation to skeletal health: An epidemiologic examination of bone mineral density, bone turnover, and trends in mortality following hip fracture.

摘要

A recent report by the U.S. Surgeon General highlights the importance of skeletal health for the population. This dissertation focuses on the impact of race/ethnicity on skeletal health, but also considers the influence of age and gender.; Two studies make use of data from a study of approximately 1,000 Hispanic, black, and white men aged 30--79 years from Boston.; The first study presents bone mineral density (BMD) data at the forearm, hip, and spine by race/ethnicity. Black men had higher BMD than Hispanic and white men. Differences between Hispanics and whites were less consistent. Age-related declines in BMD varied by skeletal site, were similar in black and white men, and were more pronounced at the lumbar spine among Hispanic men.; The second study describes levels of bone turnover using serum markers of bone formation (osteocalcin (OC)) and resorption (C-terminal telopeptides of Type-1 collagen (CTx)) by race/ethnicity. Race/ethnic groups had similar CTx levels and white men had higher OC than black men. OC and CTx changed little with age in black and Hispanic men. In white men, OC and CTx declined into mid-life and then increased thereafter.; The third study examines trends in mortality following hip fracture from 1992--1999 with U.S. Medicare data. Expected death rates were calculated from National Center for Health Statistics data. Between 1992--1999 standardized mortality ratios (SMRs) increased by 12.6%, 14.2%, and 13.9%, respectively, for 30-, 90-, 365-day mortality. The time trend in SMRs was more pronounced among younger (65--69 years) vs. older (85+ years) persons but showed no variation with gender or race/ethnicity.; These studies add to the literature on osteoporosis. There is a small age decline in bone density in black and white men; Hispanic men appear to have a more rapid decline. Bone turnover changes little with age in black and Hispanic men, but increases into late life in white men. Relative mortality rates following hip fracture increased more than 10% during the 1990s. These findings have important implications when considered in light of projected changes in the U.S. elderly population expected over the next few decades.