Incidence and risk factors of subsequent osteoporotic fracture: a nationwide cohort study in South Korea.

This study analyzed the incidence and risk factors of subsequent osteoporotic fractures in South Korea. The results showed that the incidence rate of subsequent fractures within 24 months was 10.23 per 100 person-years. Additionally, the index hip fracture site was a significant risk factor for a subsequent fracture. PURPOSE: To identify and analyze the incidence and risk factors of subsequent osteoporotic fractures in South Korea. METHODS: This retrospective cohort study analyzed data from the National Health Insurance Review and Assessment claims database from 2012 to 2017. Men and women with osteoporosis, aged ≥50 years, with index fractures between July 1, 2014, and July 1, 2015, were included. The incidence rate of subsequent fractures was calculated by determining the number of second event within 2 years from the index fracture. To identify the risk factors for subsequent fractures, we applied the Cox proportional hazard model to estimate the hazard ratios (HRs). RESULTS: Of the 73,717 patients with osteoporotic fractures, 13,203 (17.91%) had a subsequent fracture. The incidence rate of subsequent fractures within 24 months was 10.23/100 person-years. The index fracture site was a significant risk factor for a subsequent fracture, with the hip showing the highest risk (HR, 7.51; 95% confidence interval [CI], 6.77-8.34), followed by the vertebra (HR, 1.99; 95% CI, 1.91-2.06). The risk of subsequent fractures increased with a higher Charlson Comorbidity Index (CCI) score (CCI score ≥ 5: HR, 1.79; 95% CI, 1.67-1.92). CONCLUSION: The incidence rate of subsequent osteoporotic fractures in South Korea is similar or higher than that reported in the USA and Europe. A hip fracture within the prior 2 years, relative to other fracture sites, significantly increased the risk of subsequent fractures in osteoporosis patients. Patients who have these risk factors need closer disease management to prevent subsequent fractures.

Economic burden of subsequent fracture in osteoporosis patients in South Korea.

OBJECTIVES: This study aimed to assess the economic burden of subsequent fracture in osteoporosis patients with incident fracture. METHODS: The authors conducted a retrospective cohort analysis of the South Korean national health insurance claims data. Study subjects included osteoporosis patients aged ≥50 with incident fracture (July 1, 2014-June 30, 2015). Fracture-related 1-year healthcare cost was evaluated after incident fracture for patients with and without subsequent fracture, defined as a fracture occurring within 2 years from incident fracture at a different site or at the same site after 6-months washout period. Per-patient-per-month (PPPM) cost was calculated by dividing each patient's cumulative healthcare cost until subsequent fracture with time-to-subsequent-fracture. For the patients without subsequent fracture, PPPM cost equaled 1-year monthly cost. A generalized linear model (GLM) was used to estimate the ratio of increase in healthcare cost to assess the economic impact of subsequent fracture. RESULTS: A total of 73,717 osteoporosis patients with incident fracture were identified, consisting of 52.1% vertebral, 1.9% hip, and 46.0% non-vertebral-non-hip fractures. Subsequent fracture occurred in 17.9% of patients with average time-to-subsequent-fracture of 256 days. Patients with subsequent fracture had significantly higher 1-year healthcare cost after incident fracture than those without subsequent fracture ($4,307 vs $1,721) and the difference was greater in PPPM cost ($930 vs $141). GLM analysis showed that having subsequent fracture increased both 1-year healthcare cost and PPPM cost by 1.91-fold (95% CI = 1.87-1.95) and 6.14-fold (95% CI = 5.99-6.28), respectively. CONCLUSIONS: Subsequent fracture imposes a substantial burden on osteoporosis patients and, therefore, more efforts are needed for preventing subsequent fracture among osteoporosis patients.