Background   Drug-induced liver injury (DILI) is a potential adverse drug event, and its annual incidence is increasing yearly. Meanwhile, the presentation of DILI with autoimmunity highlights the critical role of the autoimmune response in the progression of DILI, but there are relatively few studies in this area.

  Objective   To retrospectively analyze the clinical characteristics of DILI in the elderly and explore the factors associated with autoimmunity.

  Methods   This study was performed on 380 elderly patients (≥60 years old) with biopsy-proven DILI admitted to our hospital from January 2012 to September 2022, and their clinical data at the time of liver biopsy were retrieved through electronic medical records. Hepatic inflammation and fibrosis were assessed by the Scheuer scoring system. According to different degrees of autoimmunity, patients were divided into without autoimmunity group, DILI combined with autoimmunity group, and DILI with drug-induced autoimmune hepatitis group, and influencing factors of DILI with autoimmunity were analyzed by the trend test and the multivariate ordinal polytomous logistic regression.

  Results   The median age of 380 elderly patients with DILI was 63.3 (IQR: 61.0-66.0) years, and 280 cases (73.7%) were female. Cholestasis (46.8%) liver injury was the main pattern. Cardiovascular drugs (18.4%) were the most common suspicious drugs of DILI. There were 219 cases (57.6%) in the autoimmunity group, 106 cases (27.9%) in the autoimmunity group, and 55 cases (14.5%) in the drug-induced autoimmune hepatitis group. Multivariate analysis showed that female (OR=2.666, 95% CI: 1.613-4.524, P=0.000), patients with hyperlipemia (OR=1.660, 95% CI: 1.066-2.582, P=0.025), with severe hepatic inflammation (taking mild as a reference, OR=1.959, 95% CI: 1.120-3.458, P=0.019), and with moderate hepatic fibrosis and cirrhosis (taking mild as a reference, OR=1.741, 95% CI:1.090-2.799, P=0.021; OR=3.125, 95% CI: 1.510-6.466, P=0.002) were more likely to have autoimmunity.

  Conclusion   Among elderly patients with DILI, female is more prone to have autoimmunity, and those with autoimmunity have severe liver inflammation and fibrosis, requiring more aggressive treatment.