Association between the concurrence of pre-existing chronic liver disease and worse prognosis in patients with an herb- Polygonum multiflorum thunb. induced liver injury: a case-control study from a specialised liver disease center in China

ObjectivesThe present study aimed to evaluate the association between the concurrence of pre-existing chronic liver diseases (CLD) and worse prognosis in patients with HILI.DesignA case–control study.SettingTertiary hospital specialising in liver diseases in China.Participants145 hospitalised HILI patients were assessed with respect to prognosis by comparing HILI with or without pre-existing CLD from February 2007 to January 2017. Twenty-five HILI cases with pre-existing alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD) and 200 ALD or NAFLD controls matched 1:8 for sex, age (±4 years old), body mass index (±2 kg/m2), the type of CLD, alcohol intake (±5 g/d) and the presence or absence of cirrhosis.Primary outcome measuresMortality and chronicity in HILI patients with or without pre-existing CLD, and matched CLD patients.ResultsOf the 193 714 hospitalised patients with liver diseases, 5703 patients met the diagnostic criteria for drug-induced liver injury (DILI), which was attributed to Polygonum multiflorum Thunb. (PMT) in 145 patients. Among these HILI patients, 22.8% (33 of 145) had pre-existing CLD, including 17 (51.5%) with ALD, 8 (24.2%) with NAFLD, 5 (15.2%) with chronic viral hepatitis and 3 (9.1%) with autoimmune liver disease. Compared with HILI patients without CLD, HILI patients with pre-existing CLD showed higher mortality (0.9% vs 9.1%, p=0.037) and higher chronicity (12.5% vs 30.3%, p=0.016). Compared with matched ALD (136 patients) or NAFLD (64 patients) patients, HILI patients with pre-existing ALD showed higher chronicity (35.3% vs 11.8%, p=0.019). Multivariate logistic regression analysis found that concurrence of pre-existing CLD was an independent risk factor for both of chronicity and mortality (OR 3.966, 95% CI 1.501 to 10.477, p=0.005), especially the chronicity (OR 3.035, 95% CI 1.115 to 8.259, p=0.030).ConclusionsConcurrence of pre-existing CLD could be an independent risk factor for worse prognosis, especially chronicity, in PMT-related HILI.