Patients with atrial fibrillation and common exclusion criteria from clinical trials are at high risk of clinical events: the Murcia AF Project II (MAFP-II) cohort study

Background: Some clinical characteristics and comorbidities in atrial fibrillation (AF) patients are exclusion criteria in randomized clinical trials (RCTs) investigating oral anticoagulants (OAC). However, these conditions are present also in everyday clinical practice patients. We compared the risk of adverse clinical outcomes between patients with and without RCT exclusion criteria.

Methods: The Murcia AF Project II was an observational cohort study including AF outpatients starting vitamin K antagonists (VKAs) from July 2016 to June 2018. For the selection of the exclusion criteria, the four pivotal RCTs of direct-acting OAC (DOACs) were used as reference. During 2 years, all ischemic strokes/transient ischemic attacks, major adverse cardiovascular events (MACEs), major bleeds, and all-cause deaths were recorded.

Results: 1050 patients (51.5% female, median age 77 years) were included, of whom 368 (35%) met at least one exclusion criterion for RCTs. During follow-up, the incidence rate ratios for major bleeding, MACE and all-cause mortality were higher among patients with exclusion criteria (all p < 0.001). Patients fulfilling at least one exclusion criterion had increased risks of major bleeding (aHR 1.48; 95% CI 1.22-1.81; p < 0.001), MACE (aHR 1.51, 95% CI 1.10-2.09, p = 0.012), and mortality (aHR 3.22, 95% CI 2.32-4.48, p < 0.001), as well as a lower event-free survival (all log-rank p < 0.001).

Conclusions: In this AF cohort taking VKAs, more than one-third had at least one RCT exclusion criteria, which translates into higher risk of major bleeding, MACE, and death. These observations should be considered when translating RCTs results to AF patients for a proper and a more patient-centered management.