Renal Dysfunction Affects Anticoagulation Control With Warfarin and Outcomes in Japanese Elderly Patients With Non-Valvular Atrial Fibrillation

Safety and Effectiveness of Apixaban Versus Warfarin in Japanese Patients with Nonvalvular Atrial Fibrillation Stratified by Renal Function: A Retrospective Cohort Study

BACKGROUND

We previously conducted a retrospective cohort study using chart review of oral anticoagulant-naïve Japanese patients with nonvalvular atrial fibrillation (NVAF) that assessed the risk of major bleeding and stroke/systemic embolism (SE) events of apixaban versus warfarin.

METHODS

In this subgroup analysis, we compared the risk of major bleeding and stroke/SE events by stratifying patients into four subgroups matched 1:1 using propensity score matching (PSM) according to baseline creatinine clearance (CrCl; mL/min): ≥ 15 to < 30, ≥ 30 to < 50, ≥ 50 to < 80, and ≥ 80.

RESULTS

Of the 7074 patients in the apixaban group and 4998 in the warfarin group eligible for inclusion in the analysis, 4385 were included in each group after PSM. Incidence rates of major bleeding and stroke/SE events were generally lower with apixaban versus warfarin across the CrCl subgroups. When all patients with a CrCl change of < 0 mL/min per year during the study period (apixaban, n = 3871; warfarin, n = 2635) were stratified into four subgroups based on the magnitude of CrCl decline (median CrCl change [mL/min] per year: - 1.09, - 3.48, - 7.54, and - 36.92 for apixaban, and - 1.10, - 3.65, - 7.85, and - 40.40 for warfarin), the incidence rates of major bleeding and stroke/SE events generally increased with an increasing CrCl decline per year in both groups.

CONCLUSIONS

In Japanese patients with NVAF, the safety and effectiveness of apixaban and warfarin were consistent across different renal subgroups, including those with severe renal impairment. Our results highlight the importance of monitoring renal function variations over time in patients with NVAF.

CLINICALTRIALS

GOV IDENTIFIER

NCT03765242.

Ischemic stroke, hemorrhage, and mortality in patients with non-valvular atrial fibrillation and renal dysfunction treated with rivaroxaban: sub-analysis of the EXPAND study

The EXPAND Study demonstrated the effectiveness and safety of rivaroxaban in patients with non-valvular atrial fibrillation (NVAF) in routine clinical practice in Japan. This sub-analysis was conducted to reveal the effectiveness and safety of rivaroxaban in Japanese NVAF patients according to baseline creatinine clearance (CrCl) levels and rivaroxaban doses in the EXPAND Study. We examined 6806 patients whose baseline CrCl data were available and classified them into 2 groups: normal renal function group with CrCl ≥ 50 mL/min (n = 5326, 78%) and renal dysfunction group with CrCl < 50 mL/min (n = 1480, 22%). In the normal renal function group, 1609 (30%) received 10 mg/day (under-dose), while in the renal dysfunction group, 108 (7%) received 15 mg/day (over-dose). In the normal renal function group, under-dose of rivaroxaban was associated with higher all-cause mortality, while in the renal dysfunction group, over-dose was associated with higher incidence of major bleeding. In contrast, the incidence of stroke or systemic embolism was not different between the 2 groups regardless of the dose of rivaroxaban. In the propensity score matched analysis to adjust the difference in characteristics according to doses of rivaroxaban, the incidences of clinical outcomes were comparable between the 2 dose groups in both renal function groups. These results indicate that the dose of rivaroxaban should be reduced depending on the renal function, considering the balance between risks of bleeding and ischemia.

Predictive ability of creatinine clearance versus estimated glomerular filtration rate for outcomes in patients with non-valvular atrial fibrillation: Subanalysis of the J-RHYTHM Registry

BACKGROUND

Renal impairment is a risk factor for various adverse events, especially for death. In general, creatinine clearance (CrCl) is used for dose-adjustments of many drugs including oral anticoagulants, and estimated glomerular filtration rate (eGFR) is adopted for the diagnosis of chronic kidney disease. Predictive ability of CrCl versus eGFR for outcomes in patients with non-valvular atrial fibrillation (NVAF) remains controversial; therefore, this was compared using data from the J-RHYTHM Registry.

METHODS

Out of 7406 outpatients with NVAF from 158 institutions, 6004 (age, 69.7 ± 9.9 years; men, 71.2%) having data of CrCl (mL/min, by the Cockcroft-Gault formula), eGFR (mL/min/1.73 m2, by the equations of the Japanese Society of Nephrology), and body surface area (BSA) were analyzed. C-statistics (area under the receiver-operating characteristic curve) of CrCl and eGFR for events were compared by DeLong's test.

RESULTS

Thromboembolism, major hemorrhage, and all-cause death occurred in 107 (1.8%), 117 (1.9%), and 154 (2.6%) patients during the 2-year follow-up period. C-statistics of CrCl for each event were 0.609 (95% confidence interval, 0.559-0.658), 0.599 (0.548-0.657), and 0.746 (0.706-0.786); and those of eGFR were 0.542 (0.487-0.597), 0.573 (0.519-0.626), and 0.677 (0.631-0.723), respectively. C-statistics of CrCl for thromboembolism and all-cause death were significantly higher than those of eGFR (P < 0.001 for both). These results were consistent when BSA-unadjusted eGFR was used instead of eGFR (P = 0.002 for thromboembolism and P < 0.001 for all-cause death).

CONCLUSIONS

CrCl was superior to eGFR in the prediction of adverse outcomes, i.e., thromboembolism and all-cause death in Japanese patients with NVAF.

Moderate chronic kidney disease and left atrial enlargement independently predict thromboembolic events and mortality in elderly patients with atrial fibrillation: a retrospective single-center study

Objective

This study aimed to evaluate the effects of moderate chronic kidney disease (CKD) and left atrial enlargement on the risks of thromboembolic events, and all-cause and cardiovascular mortalities in elderly patients with atrial fibrillation (AF).

Methods

We retrospectively studied 751 patients (82.16% men, mean age: 79.0±9.1 years) with AF who were followed up for an average of 34.5 months at a single center. Adjusted hazard ratios (HRs) of risk factors for adverse clinical events were calculated using the Cox proportional hazards model.

Results

The risks of thromboembolic events, and all-cause and cardiovascular deaths were higher in patients with moderate CKD compared with patients with normal renal function after adjusting for other traditional risk factors (HR: 1.63, 95% confidence interval (CI): 1.03–2.58; HR: 1.55, 95% CI: 1.08–2.23; HR: 3.49, 95% CI: 1.57–7.74; respectively). Left atrial volume index >28.0 mL/m² was an independent risk factor associated with thromboembolic events and all-cause and cardiovascular deaths (HR: 1.62, 95% CI: 1.21–2.33; HR: 1.56, 95% CI: 1.16–2.10; HR: 1.87, 95% CI: 1.07–3.28; respectively).

Conclusions

Moderate CKD and left atrial enlargement may predict thromboembolic events, and all-cause and cardiovascular mortalities in elderly patients with AF without anticoagulation therapy.