Supplementary Material for: Characteristics and Healthcare Costs in the Aging Hepatitis B Population of Japan: A Nationwide Real-World Analysis

<b><i>Introduction:</i></b> Advancing age, comorbidity, and financial burden have been observed in chronic hepatitis B (CHB) patients globally. As Japan is leading the world in aging demographics, similar real-world data are urgently needed for its CHB population to inform all stakeholders. <b><i>Methods:</i></b> This cross-sectional study characterized the demographics, comorbidities, and healthcare costs of a large Japanese real-world adult (≥18 years) CHB patient (ICD-10: B18.1) population from the Medical Data Vision database from January 01, 2012, to December 31, 2016. Comorbidities were identified by ICD-10 codes, and the annual point prevalence and Charlson Comorbidity Index (CCI) score were calculated. Annual mean and median all-cause healthcare utilization and costs per patient were calculated. Comparison tests were conducted for CCI scores, prevalence of comorbidities, and healthcare resource utilization and costs. <b><i>Results:</i></b> We identified 11,125 CHB patients. Between 2012 and 2016, the mean age increased from 62.0 to 65.2 years, and the percentage of those aged ≥65 years increased from 45.6% to 60.7%. The prevalence of cirrhosis remained similar (5.8% in 2012 and 5.6% in 2016, <i>p</i> = 0.69) while hepatocellular carcinoma decreased from 6.3% to 4.5% (<i>p</i> &lt; 0.01). The prevalence of nonliver comorbidities increased (40.9–52.0% for cancer [<i>p</i> &lt; 0.01], 12.1–17.7% for osteoporosis [<i>p</i> &lt; 0.01], and 10.7–15.0% for renal impairment [<i>p</i> &lt; 0.01]). Healthcare resource utilization and costs also increased, with a 119.3% increase in median total healthcare costs from JPY 229,143 in 2012 to 502,467 in 2016 (<i>p</i> &lt; 0.01). <b><i>Conclusions:</i></b> The CHB population of Japan is predominantly elderly and carry a high nonliver comorbidity burden, while incurring increasing healthcare costs.