OBJECTIVES: This research aims to provide a theoretical estimate of the prevalence of osteoporosis in patients undergoing spine fusion surgery, by utilizing data from the past decade to estimate the prevalence of osteoporosis over the next 30 years.

METHODS: This theoretical model uses the Japanese Medical Data Vision (JMDV) – spine fusion patient dataset from April 1, 2008, through September 30, 2019. Osteoporotic patients were identified with diagnostic codes or by receipt of osteoporotic medication. We estimated the number of patients with osteoporosis undergoing spine fusion surgery up until December 2050 using ARIMA (Autoregressive integrated moving average), Exponential Smoothing and Poisson Regression. Root mean square error (RMSE) and Akaike information criterion (AIC) were used to evaluate the prediction accuracy of each of the three models.

RESULTS: In our theoretic model, the prevalence of osteoporosis in patients undergoing spine fusion surgery is estimated to increase by up to 232%. This model assumes the increase trends observed over the past 10 years will continue unchanged over the next 30 years, therefore the number of patients with osteoporosis undergoing spine fusion surgery will increase from 25 per 100 patients [95% CI 22-27] to up to 83 per 100 patients [95% CI 72-93] using the Exponential Smoothing model by December 2050. The female cohort and patients aged 70 to 79 years had the highest rate of increase in the prevalence of osteoporosis. The forecast using the exponential smoothing method produced models with AIC and RMSE of 387.76 and 1.85.

CONCLUSIONS: The exponential smoothing method was found to be the most reliable method for predicting the increase trend. Using this theoretical estimate the increase prevalence of osteoporosis amongst spine fusion patients over the next 30 years, could increase the demand on the healthcare system in Japan given the known increased burden of osteoporosis on spine fusion surgery.