ABSTRACT
BACKGROUND: Osteoporotic fractures pose a major public problem, not only in Western populations but also of increasing significance in Asian populations. However, most previous studies for the prevalence of osteoporosis in Korea were carried out from the data of hospitalized or out-patient based subjects, hospital staff, healthy volunteers and so forth. The purpose of present study was to evaluate the normative data of bone mineral density (BMD) in Korean young and perimenopausal women and to determine the prevalence and risk factors of low bone mass, including osteoporosis and osteopenia in a community-based population. METHODS: In 1999, a baseline survey was carried out in the Dong-gu of Ulsan city, a urban area but located in seashore of southeastern Korea. The selected community sample of 3,822 inhabitants (all were women aged 49~54 years) were chosen. We studied 1,629 women among them and 127 healthy women aged 20~35 years. BMD of lumbar spine and femur was measured using dual-energy X-ray absorptiometry. For analysis of risk factors, those were excluded who was the current or recent user of estrogen and who had osteoporosis related disease or unknown menopause due to previous hysterectomy. Thus, 1,020 subjects were analysed for the association of low BMD and risk factors. Significant determinants of BMD were investigated using univariate and multiple regression analysis. RESULTS: When our young normal data were used, 9.8% for the lumbar spine and 1.4% for the femoral neck of our study population (n=1,629) were classified as osteoporosis. Among them, the menopausal status of above 1,020 subjects had independent association with low BMD (T-score<-1.0) of both lumbar spine (odds ratio=4.71 in postmenopause, p<0.001) and femoral neck (odds ratio=2.86 in postmenopause, p<0.001). In premenopausal women (n=507), weight and age of menarche were associated independently with low bone mass, including osteoporosis and osteopenia of both lumbar spine and femoral neck. In postmenopausal women (n=513), weight and duration since menopause were associated independently with low bone mass of both lumbar spine and femoral neck. Also, daily amount of calcium intake had significant association (regression coefficient=0.047; p<0.05) independently with BMD of femoral neck. CONCLUSION: The results of this population-based study suggest that it is important to prevent bone loss and screen the BMD in women aged 49~54 years with menopause, low body weight, late menarche, prolonged duration since menopause, low calcium intake.