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.