RESUMO
OBJECTIVE To analyze influential factors for dabigatran exposure in elderly patients with non-valvular atrial fibrillation. METHODS The clinical information of 75 elderly patients diagnosed with non-valvular atrial fibrillation was collected from our hospital in Jan. 2019-Jun. 2020. One or two steady-state blood drug concentration samples were collected from each patient. NONMEM 7.2.0 software was used to establish a population pharmacokinetics model of dabigatran； the effects of different covariates on the apparent clearance of dabigatran were investigated， and the final model was verified by goodness of fit and Bootstrap method； NONMEM 7.2.0 software was used to analyze the drug exposure of ordinary elderly patients and elderly patients after taking dabigatran ester in different disease states. RESULTS Totally 122 blood concentration samples of dabigatran were collected. Advanced age， creatinine clearance and history of chronic heart failure were screened out as three significant covariates that influenced the clearance of dabigatran in elderly patients. The exposure of population with advanced age increased by about 50% compared with the general elderly， the exposure of population with history of chronic heart failure increased by nearly 30% compared with population without， and the exposure of population with moderate and severe renal injury increased by about 30% and 80% compared with mild. CONCLUSIONS Advanced age， renal injury and history of chronic heart failure are influential factors for elevated systemic exposure of dabigatran.