Relationship between hormone replacement therapy and spinal osteoarthritis: a nationwide health survey analysis of the elderly Korean population

OBJECTIVES To identify the effects of hormone replacement therapy (HRT) on spinal osteoarthritis (OA). METHODS AND DESIGN A cross-sectional study of a nationwide survey was performed. SETTING This study collected data from the fifth Korean National Health and Nutrition Examination Survey (2010-2012). PARTICIPANTS After excluding ineligible respondents, the total number of participants in this study was 4265 females. Participants were asked to report symptoms and disabilities related to spinal OA. In addition, plain radiographs of the spine were taken of all patients. PRIMARY AND SECONDARY OUTCOME MEASURES Demographic and lifestyle variables were compared between the HRT and non-HRT groups. In addition, radiographic examination and symptom assessment were performed to determine the existence of spinal OA. RESULTS Marital status, education, income and HRT were correlated with spinal OA. A risk analysis of related factors showed that HRT and age had effects on spinal OA (ORs 0.717 and 1.257). Nevertheless, in the HRT group, smokers had a increased risk of spinal OA. In addition, the HRT group demonstrated a lower prevalence of spinal OA. The calculated risk for compromised morbidity with HRT compared with the prevalence of spinal OA was 0.717 (OR). The duration of HRT was also related to the risk for spinal OA. The group that had been taking HRT for more than 1 year showed decreased risk (OR 0.686) compared with patients with <1 year of HRT (OR 0.744; P<0.05). CONCLUSION Women receiving HRT showed a lower prevalence of spinal OA. HRT also correlated with a decrease in spinal OA morbidity.