Short and long-term renal function changes with direct oral anticoagulants in elderly patients with atrial fibrillation

Abstract Background Atrial Fibrillation (AF) and chronic kidney disease (CKD) frequently coexist in elderly patient. Previous evidence showed that vitamin K antagonists (VKAs) may be associated with an accelerated decrease of estimated glomerular filtration rate (eGFR) compared to direct oral anticoagulants (DOACs). However, there is little evidence on DOACs in the elderly population and in real life settings; the evidence available to us comes from randomized clinical trials with younger populations. Purpose The main objective of this study was to investigate the medium to long term renal function changes in older AF patients treated with DOACs and VKAs. Methods Enrolled patients underwent 3 eGFR measurements during follow-up, and the between arms difference in eGFR lost over time was investigated by 1) the Linear Mixed Models (LMM) and 2) group-based trajectory model (GBTM) analyses. Analysis was done according to short-term (3.2 years) and long-term follow-up (6.7 years). During the study period 420 enrolled AF patients (77.0±6.0 years, 136 on VKAs and 284 on DOACs) underwent 1260 eGFR assessments. Results After a median follow-up of 4.9 years, in the whole sample eGFR decreased from 67.4±18.2 ml/min/1.73 m2 to 47.1±14.3 ml/min/1.73 m2, p<0.001. Patients on DOACs experienced a significantly lower eGFR decrease that those treated with VKAs (-21.3% vs -45.1%, p<0.001). The benefit of DOACs compared with VKAs was evident both in the short term (eGFR decline -6.6 (95% CI: -9.1 to -4.0) ml/min/1.73 m2 vs -19.9 (95% CI: -23.6 to -16.2) ml/min/1.73 m2 respectively) and in the long-term, (eGFR -13.5 (95% CI: -16.1 to -11.0) ml/min/1.73 m2 in DOACs group vs -34.2 (95% CI: -37.9 to -30.5) ml/min/1.73 m2), respectively). After stratifying our study population into 5 groups according to trajectories of renal function decline, from the first (lowest decline in eGFR) to the fifth (greatest decline in eGFR), the first trajectory consisted of 80% patients on DOACs therapy. Logistic regression showed that the group on DOACs therapy was 3.03- to 4.24-fold more likely to belong to the trajectory with less eGFR decline than the VKAs group. Conclusions In conclusion, DOACs were associated with less long term decline in renal function in elderly patients with AF compared with VKAs.