ABSTRACT
BACKGROUND: Little is known how individual time-in-therapeutic-range (TTR) impacts the effectiveness and safety of warfarin therapy compared to direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF). OBJECTIVE: To compare the effectiveness and safety of standard dose DOACs to warfarin in patients with AF, while categorizing warfarin treated patients into quartiles based on their individual TTR. MATERIALS AND METHODS: We conducted a nationwide study including all patients with new-onset AF between 2011 and 2018 in Finland. Hazard ratios (HR) were calculated using Cox regression analysis with the inverse probability of treatment weighted method to assess the risks of ischaemic stroke (IS), intracranial haemorrhage (ICH) and mortality for users of apixaban (n = 12,426), dabigatran (n = 4545), rivaroxaban (n = 12,950) and warfarin (n = 43,548). RESULTS: The median TTR for warfarin users was 72%. Compared to the second best TTR quartile (reference), the risk of IS was higher in the two poorest TTR quartiles, and lower in the best TTR quartile and on rivaroxaban [2.35 (95% confidence interval, 1.85-2.85), 1.44 (1.18-1.75), 0.60 (0.47-0.77) and 0.72 (0.56-0.92)]. These differences were non-significant for apixaban and dabigatran. HR of ICH was 6.38 (4.88-8.35) and 1.87 (1.41-2.49) in the two poorest TTR groups, 1.44 (1.02-1.93) on rivaroxaban, and 0.58 (0.40-0.85) in the best TTR group compared to the reference group. Mortality was higher in the two poorest TTR groups and lowest in the best TTR group. CONCLUSIONS: The outcome was unsatisfactory in the two lowest TTR quartiles - in half of the patients treated with warfarin. The differences between the high TTR groups and standard dose DOACs were absent or modest.
Subject(s)
Anticoagulants , Atrial Fibrillation , Dabigatran , Pyrazoles , Pyridones , Rivaroxaban , Warfarin , Humans , Warfarin/adverse effects , Warfarin/administration & dosage , Atrial Fibrillation/drug therapy , Atrial Fibrillation/complications , Male , Female , Aged , Anticoagulants/adverse effects , Anticoagulants/administration & dosage , Finland/epidemiology , Rivaroxaban/adverse effects , Rivaroxaban/administration & dosage , Pyridones/administration & dosage , Pyridones/adverse effects , Pyridones/therapeutic use , Middle Aged , Pyrazoles/administration & dosage , Pyrazoles/adverse effects , Dabigatran/adverse effects , Dabigatran/administration & dosage , Administration, Oral , Aged, 80 and over , Cohort Studies , Intracranial Hemorrhages/chemically induced , Intracranial Hemorrhages/epidemiology , Stroke/prevention & control , Stroke/epidemiology , Stroke/etiology , Ischemic Stroke/prevention & control , Ischemic Stroke/epidemiology , Ischemic Stroke/etiology , International Normalized Ratio , Treatment OutcomeABSTRACT
INTRODUCTION: Chronic kidney disease (CKD) is associated with an increased incidence of atrial fibrillation (AF). Also, patients with AF are prone to adverse kidney outcomes. We examined comorbidities and medication use in patients with CKD and incident AF. METHODS: The Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a nationwide retrospective register-linkage study including data from 168,233 patients with incident AF from 2007 to 2018, with laboratory data from 2010 onwards. Estimated glomerular filtration rate (eGFR) was available for 124,936 patients. The cohort was divided into 5 CKD stages with separate groups for dialysis and kidney transplantation. RESULTS: At AF diagnosis eGFR <60 mL/min/1.73 m2 was found in 27%, while 318 (0.3%) patients were on dialysis, and 188 (0.2%) had a functioning kidney transplant. Lowering eGFR yielded more comorbidities and medications. During 2010-2018 in patients with eGFR <60 mL/min/1.73 m2 prevalence of hypertension, dyslipidaemia, and diabetes increased from 82 to 88%, from 50 to 66% and from 25 to 33%, respectively (<0.001). Throughout the observation period, lipid-lowering medication was underused. CONCLUSION: More than one-fourth of patients with incident AF also had CKD stage 3-5 (eGFR <60 mL/min/1.73 m2). Both comorbidities and medication use increased with worsening kidney function. Prevalence of major cardiovascular (CV) risk factors increased during 2010-2018, but the use of survival-affecting medications, such as lipid-lowering medication, was suboptimal at all stages of CKD. More attention should be given to the optimal treatment of risk factors in this high CV risk population.