Patients who received anticoagulants because they were diagnosed with atrial fibrillation (AF) while hospitalized for acute coronary syndrome (ACS), acute pulmonary disease, or sepsis did not see benefit from anticoagulants, according to a recent study.
The retrospective cohort study include 2,304 Canadian patients ages 65 years or older who were hospitalized with a primary diagnosis of ACS, acute pulmonary disease (defined as chronic obstructive pulmonary disease, pneumonia/influenza, pulmonary embolism, or pleural effusion), or sepsis from 1999 to 2015. All were diagnosed with new-onset AF as a secondary complication. Results were published online Sept. 27 by JACC: Clinical Electrophysiology.
A third of the patients were discharged on anticoagulation. Over a three-year follow-up period, receiving anticoagulation was not associated with a significant reduction in ischemic stroke in any of the primary diagnosis groups (adjusted odds ratio [OR], 1.22 [95% CI, 0.65 to 2.27] for ACS, 0.97 [95% CI, 0.53 to 1.77] for pulmonary disease, and 1.98 [95% CI, 0.29 to 13.47] for sepsis). Anticoagulation was associated with a significantly increased risk of bleeding in patients with acute pulmonary disease (OR, 1.72; 95% CI, 1.23 to 2.39). There was a trend toward higher bleeding risk in ACS patients (OR, 1.42; 95% CI, 0.94 to 2.14) and no effect in sepsis patients (OR, 0.96; 95% CI, 0.29 to 3.21).
The results show that clinicians were less likely to use anticoagulation in patients with secondary AF, compared to those with primary AF, among whom other studies have shown anticoagulation rates of 46% to 60%, the authors observed. This study's patient population had high rates of comorbidity and thus high risk for both bleeding and stroke (approximately 45% to 60% with a HAS-BLED score ≥3 and approximately 60% to 65% with a CHADS2 score ≥2). They had a higher risk for bleeding (3.6 to 6.2 per 100 person-years) than for stroke (1.1 to 1.6 per 100 person-years). “One possibility for the lack of observed benefit in anticoagulation is that risk of stroke and bleeding may be different in secondary AF compared to primary AF,” the authors suggested.
The study was limited by inability to determine whether AF was transient, the overall low incidence of stroke, and infrequent use of direct-acting oral anticoagulants, among other factors. Still, the results show that it is unclear whether anticoagulation benefits patients who develop AF secondary to ACS, acute pulmonary disease, or sepsis and support individual assessment rather than routine use of anticoagulants in this patient population, according to the authors.