Kidney Week

Abstract: TH-PO1046

Impact of Kidney Function on Quality of Anticoagulation in Adults with Atrial Fibrillation: The CVRN WAVE Study

Session Information

• CKD: Epidemiology, Risk Factors, Prevention - I
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 1901 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention

Authors

• Go, Alan S., Kaiser Permanente Northern California, Oakland, California, United States

Alan S. Go,

• Fan, Dongjie, Kaiser permanente, Oakland, California, United States

Dongjie Fan,

• Sung, Sue hee, Kaiser Permanente Northern California, Oakland, California, United States

Sue hee Sung,

• Williams, Marc S., Geisinger, Danville, Pennsylvania, United States

Marc S. Williams,

• Tan, Thida C., Kaiser Permanente Northern California, Oakland, California, United States

Thida C. Tan,

• Gurwitz, Jerry H., Meyers Primary Care Institute , Worcester, Massachusetts, United States

Jerry H. Gurwitz,

Background

Despite the development of direct oral anticoagulants, warfarin remains an important anticoagulation option for stroke prevention in adults with CKD. However, the impact of kidney function on the quality of anticoagulation for atrial fibrillation (AF) has not been well-defined.

Methods

Across 5 participating healthcare systems in the Cardiovascular Research Network (CVRN), we identified all adults with diagnosed AF who initiated warfarin and had ≥1 follow up international normalized ratio (INR) measurement. We used multivariable logistic regression, Cox regression and Kaplan-Meier curves to assess the relationship between estimated glomerular filtration rate (eGFR) by CKD-EPI with three metrics of quality of anticoagulation: patient-level %TTR, time to achieve a stable INR [between 2.0-3.0], and early warfarin termination. Stroke and bleeding risk factors were ascertained from health system electronic health records.

Results

Among 24,634 eligible patients, mean age was 73 years and 44% were women. Baseline eGFR (ml/min/1.73 m²) was 64% for eGFR ≥60, 22% for eGFR 45-59, 11% for eGFR 30-44, 2.5% for eGFR 15-29 and 2% for eGFR <15 or receiving dialysis. Patient-level %TTR ranged from 43% for eGFR <15 or dialysis to 66% for eGFR ≥60, with a graded increased adjusted odds of poorer anticoagulation control with lower eGFR. Overall, 77% reached a stable INR within the first 90 days of therapy, with only eGFR <15 or dialysis significantly associated with a longer time to reach stable INR. There was no significant association of kidney function with early warfarin termination.

Conclusion

In adults with AF starting warfarin, we found graded increased odds of suboptimal %TTR with lower eGFR. While only eGFR <15 or dialysis was associated with a lower chance of reaching a stable INR within 90 days, eGFR did not appear to influence the likelihood of stopping warfarin within the first 12 months of treatment.

Funding

• Other NIH Support