OBJECTIVES : The progression of liver fibrosis (LF) is reported to be different among patients and associated with some factors. This study evaluated the speed of LF progression in individuals using FIB-4, an indicator of the degree of LF, and investigated factors associated with LF progression.

METHODS : We used Japanese administrative claims database from acute hospitals provided by Medical Data Vision Co., Ltd. (April 2008-May 2019). Patients diagnosed with either chronic liver disease or diabetes, those having ≥5-year observation period from first record of FIB-4 (index), and ≥5 records of FIB-4 within the observation period were extracted. FIB-4 was calculated using platelet, ALT, AST values and patient age. We estimated the following regression model in each patient: FIB-4 (months from index (MFI)) = α + β × MFI + ε. Based on the distribution of the estimate (Est) and standard error (SE) of β, patients were selected to two groups: those who were likely to have positive value of Est (case), and those who did not have positive value (control). Patient characteristics between these groups were compared.

RESULTS : The study included 55,450 patients. Mean ± standard deviation of Est was 0.0031 ± 0.0063. We selected patients with 0.0025<Est<0.0075 and Est – 2SE< 0 for case (N = 7,904), and those with -0.0075<Est<0 and SE<0.00375 for control (N = 5,670). Case group had higher percentage of male, 55%, and higher mean age at index, 66.2 ± 11.9, than those in control group, 51% and 60.3 ± 13.6. Among the top 10 comorbidities in both groups, hypertension, constipation, chronic gastritis, low back pain and gastric ulcer were more common in case group than in control group.

CONCLUSIONS : The speed of LF progression widely varied between patients. The higher speed was associated with male, older age, and some lifestyle-related diseases.