Comorbidities and healthcare costs and resource use of patients with nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) in the Japan medical data vision database

Background This study examined demographics, comorbidities and healthcare resource use (HCRU) and costs among Japanese patients with nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Methods We conducted a repeated cross-sectional analysis of the Medical Data Vision (MDV) claims database, from January 2011 to March 2018. Demographics were described at index date and by calendar year; a “NASH” subpopulation included patients with ≥ 1 claim for NASH at any time. Prevalence of pre-specified comorbidities of interest and data-emergent top comorbidities were estimated. All-cause HCRU and costs were quantified by calendar year. Outcomes were compared between 2011 and 2017 using partially overlapping t tests. Results 58,958 patients (mean age 61.6 years; 55.5% male) were included. 1139 patients (2%) were in the NASH subpopulation. At baseline, comorbid cardiovascular disease (69.4%), diabetes (62.1%) and hyperlipidaemia (54.4%) were most prevalent; comorbidity prevalence increased with age. Mean outpatient visits decreased from 9.36 per patient in 2011 to 7.80 in 2017; mean inpatient admissions increased (both p < 0.001 for 2011 vs 2017). Mean total all-cause healthcare costs ranged from ¥322,206 to ¥340,399 per patient per year between 2011 and 2017. Although total all-cause healthcare costs did not change significantly (p = 0.552), cost burden shifted from the outpatient to inpatient setting between 2011 and 2017. All-cause healthcare resource use/costs were generally higher for the NASH subgroup compared with the overall population. Conclusions There is a high burden of disease among Japanese NAFLD/NASH patients, including a high prevalence of comorbidities which generally increase with age. Accordingly, substantial all-cause HCRU and costs were incurred.