Background: Chronic kidney disease is associated with an increased risk of atrial fibrillation and cerebrovascular disease. Acceptable levels of time in the therapeutic range (TTR) are associated with better treatment outcomes.

Objective: To correlate between time in therapeutic range and glomerular filtration rate in Thai chronic kidney disease patients with atrial fibrillation.

Materials and Methods: The present study was retrospectively collected from 312 medical records of patients with atrial fibrillation aged 18 years or over at Pranangklao Hospital between January 2018 and December 2020.

Results: The average age of patients was 67.8±12.6 years and 44.9% were male. The average CHA₂DS₂-VASc scores were 3.6±1.5 and the average follow-up duration was 883.5 ± 398.4 days. Most patients had hypertension and dyslipidemia, and have been prescribed statins, proton pump inhibitors, and aspirin. Most patients had TTR of less than 65%. The present study showed patients with low estimate glomerular filtration rate (eGFR) were significantly correlated with having low TTR. A reduction of eGFR by 1 correlated with a decrease in TTR by 0.33. An equation that predicted the relationship between the eGFR and the TTR could be expressed as TTR=26.95+0.33 multiply eGFR.

Conclusion: Decreased glomerular filtration was associated with poorer anticoagulation control.

Keywords: Time in therapeutic range; Atrial fibrillation; Chronic kidney disease

DOI: 10.35755/jmedassocthai.2022.06.13325

Received 13 December 2021 | Revised 22 April 2022 | Accepted 30 April 2022