Clinical Features and Follow-up Outcomes of Individualized Low-dose DOAC Therapy in Chinese Patients Aged 60 Years and Older: A Single-center Study

Abstract

Abstract Introduction: It is common to adjust direct oral anticoagulant (DOAC) dosage individually according to the clinical characteristics and coagulation indexes of patients in clinical practice, but its effectiveness and safety are still controversial. The purpose of this study was to analyze the clinical characteristics and follow-up outcomes of elderly patients who adjusted anticoagulant therapy according to coagulation index. Method: Included were patients who were admitted to the geriatric Department of Peking University First Hospital from January 1, 2016 to December 31, 2021, with indications of anticoagulation therapy, receiving DOAC (Dabigatran, Rivaroxaban) therapy, individualized dose adjustment according to APTT (peak value of 46-60s) or AXA (peak value of 0.5-1.0IU/ml), aged ≥60 years, and complete clinical data. Outpatient or telephone follow-up every three months after discharge until termination or death or end of study (December 31, 2022). The clinical features and follow-up results of Dabigatran 110mg BID group and Dabigatran 110mg QD group, Rivaroxaban 5mg BID group and Rivaroxaban 2.5mg BID group were compared. Result: A total of 388 patients were enrolled, including 145 (35.1%) in the Dabigatrangroup and 243 (58.8%) in the rivaroxaban group. The Dabigatrangroup was divided into the 110mg BID group (85 cases) and the 110mg QD group (60 cases), and patients in the 110mg QD group were older, lighter, and had lower glomerular filtration rate (eGFR). The Rivaroxaban group was divided into the 5mg BID group (134 cases) and the 2.5mg BID group (109 cases), and patients in the 2.5mg BID group were older, weighed less, had lower activity of daily living (ADL) scores, and had lower eGFR. The mean follow-up time was 49.5±23.4 months in the Dabigatrangroup and 32.1±20.1 months in the Rivaroxaban group. Survival analysis of bleeding events, thrombotic events, and death was not significantly different between Dabigatran 110mgBID and 110mgQD and Rivaroxaban 5mgBID and 2.5mgBID groups. Conclusion: The clinical characteristics of patients with individualized low-dose DOAC regimen were as follows: age ≥80 years old, weight ≤60kg, ADL score ≤60 points, HAS-BLED score ≥3 points, eGFR < 60ml/min/1.73m², baseline hemoglobin < 120g/L. There was no significant difference in the incidence of bleeding and thrombotic events between individualized low-dose therapy based on patient clotting indicators and standard therapy.