AF patients with cognitive impairment or frailty less likely to receive OAC
Association of Frailty and Cognitive Impairment with benefits of Oral anticoagulation in patients with atrial fibrillation
Introduction and methods
Frailty is common in patients with atrial fibrillation (AF) [1,2]. AF is associated with an elevated risk of cognitive impairment, independent of stroke . If all three conditions are present, this can increase morbidity and mortality in the elderly and may affect the management of AF.
Oral anticoagulation (OAC) for stroke prevention is significantly underutilized in the elderly . Cognitive impairment and frailty may affect the understanding of bleeding risk and the decision to use anticoagulants. The impact of these co-morbid conditions on outcomes in AF is, however, unclear. However, for optimal management of this growing population of patients, it is important to understand the incidence of patients with cognitive impairment and frailty, and to identify factors associated with it and the outcomes.
This large multicenter cohort study therefore examined OAC treatment patterns, outcomes and benefits of OAC for stroke prevention as a function of cognitive impairment and frailty in 9.749 AF patients included in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) (June 2010 to August 2011). Eligible patients aged >18 years (median age: 75.0 [67.0-82.0]) had electrocardiographic documentation of AF and an anticipated life expectancy of >6 months. Cognitive impairment (3.0%) was documented by the treating physician. Frailty (5.9%) was assessed using the American Geriatric Society’s Geriatric Evaluation and Management Tool at inclusion. Median follow-up was 931 (IQR: 668-1.088) days.
Outcomes were all-cause mortality, CV mortality, stroke/TIA/non-central nervous system (CNS) systemic embolism, composite of major adverse CV and neurologic events (MACNE: CV death, myocardial infarction or stroke/TIA/non-CNS systemic embolism), major bleeding (defined per the ISTH criteria), and clinically significant bleeding (defined as bleeding event that led to a clinical intervention without meeting the major bleeding ISTH criteria).
Risk profile and OAC prescription in AF patients with cognitive impairment or frailty
- AF patients with cognitive impairment had higher CHA₂DS₂-VASc risk score (5.0 [4.0 - 6.0] vs. 4.0 [3.0 - 5.0], p<0.0001), and higher HAS-BLED and ORBIT bleeding risk scores (2.0 [2.0 - 3.0] vs. 2.0 [1.0 - 2.0], p<0.0001), compared with those without cognitive impairment.
- AF patients with frailty had higher CHA₂DS₂-VASc risk score (5.0 [4.0 - 6.0] vs. 4.0 [3.0 - 5.0], p<0.0001), and higher HAS-BLED and ORBIT bleeding risk scores (2.0 [2.0 - 3.0] vs. 2.0 [1.0 - 2.0], p<0.0001), compared with those with no frailty.
- Those with cognitive impairment were less likely to be prescribed an OAC (69.6% vs. 76.6%, p=0.0058), compared with those without cognitive impairment.
- Frail participants were less likely to be prescribed an OAC (67.5 vs 76.9%, p<0.0001), compared with those with no frailty.
Outcomes in AF patients with cognitive impairment and frailty
- Cognitive impairment and frailty were independently associated with all-cause death in AF patients (HRadj: 1.34, 95%CI: 1.05-1.72, P=0.0198 and HRadj: 1.29, 95%CI: 1.08-1.55, P=0.0060, respectively), but not with the endpoints stroke/TIA/non-CNS systemic embolism, major bleeding and clinically significant bleeding.
Impact of cognitive impairment or frailty on OAC treatment effect
- No significant interaction was observed between cognitive impairment and the effect of OAC use on all-cause death (P=0.5), major bleeding (P=0.9), and MACNE (P=0.9).
- There was no significant interaction between frailty and OAC use in examining all-cause death (P=0.8), major bleeding (P=0.3), and MACNE (P=0.4).
In this multicenter cohort study with AF patients, those with cognitive impairment or frailty had a higher predicted risk for stroke, yet were less likely to be treated with OAC therapy. Cognitive impairment or frailty were both associated with higher risk of mortality, but not stroke/TIA or major bleeding. Cognitive impairment and frailty did not appear to modify the association between OAC and outcomes. These data suggest that cognitive impairment or frailty is not a contraindication to anticoagulation in AF patients.