Association between household size, residential area, and osteoporosis: analysis of 2008 to 2011 Korea National Health and Nutrition Examination Survey

BACKGROUND/AIMS The prevalence of single-person households has rapidly increased in Korea. Individuals living alone and in rural areas may have a higher risk of various metabolic diseases due to differences in lifestyle. However, few studies have investigated the association of household size and residential area with health-related problems. This study aimed to evaluate the association of household size and residential area with risk of osteoporosis in postmenopausal women. METHODS This cross-sectional study enrolled 3,058 postmenopausal women from the 2008 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). We examined the association between bone mineral density (BMD) and household size and residential area. RESULTS Individuals living in rural areas had significantly lower BMD of the lumbar spine than those living in an urban area. Subsequently, we divided the participants into four groups according to household size and residential areas. Lumbar spine BMD was significantly lower in individuals living in rural single-person households than those in urban households with two or more individuals, even after adjustment for multiple confounding factors. In addition, individuals in rural single-person households had significantly greater odds of osteoporosis in the lumbar spine than those in urban households with two or more residents. CONCLUSIONS Individuals in rural single-person households had significantly lower BMD and greater odds of osteoporosis in lumbar spine than urban households with two or more individuals. The results of this study suggest that individuals living in rural single-person households may benefit from more careful screening for osteoporosis.