GPT and Wilson disease: Considering the occurrence of neurological symptoms as the dependent variable, elevated ALT and AST levels, 24-h urinary copper level, adherence to a low-copper diet rate, ZG dose > 210 mg/day, and PCA dose > 500 mg/day as independent variables, the multivariate logistic regression analysis showed that the low average daily therapeutic doses of PCA and ZG were independent risk factors for the development of neurological symptoms in H-WD patients (Table 2).