Abstract Body (Do not enter title and authors here): Background: Current clinical practice guidelines for atrial fibrillation (AF) recommend stroke risk stratification and the use of oral anticoagulants (OACs) for patients at risk. However, physicians’ recognition of patients’ stroke risk may differ from the calculated risk, and the effect of this discrepancy on subsequent care remains unknown.
Aims: We aimed to document treating physicians’ estimations of individual patients' stroke risk and assess its association with OAC utilization.
Methods: A multicenter, prospective cohort study was conducted in two outpatient practices in Tokyo, Japan, between 2018 to 2020. Participants included patients with newly diagnosed AF or those referred for initial treatment for AF. Treating physicians were asked to document the patient's estimated risk of stroke in numbers. The estimations were categorized as low risk (<1.0%/year), intermediate risk (1.0%≤ to <2.0%/ year), and high risk (2.0%≤/year). We then calculated patients’ baseline CHA₂DS₂-VASc scores and divided them into three risk groups: 0 or 1 point as low risk, 2 points as intermediate risk, and 3 or more points as high risk. Higher risk categorization by physicians was defined as "overestimation," while lower risk categorization was defined as "underestimation." The independent association of physician-patient risk concordance with OAC use was explored by multivariable Logistic regression models.
Results: Among the 285 patients enrolled in this study (mean age 68±12 years, male 72.6%), the mean CHA₂DS₂-VASc score was 2.3±1.6. Physicians correctly estimated stroke risk in 147 patients (51.6%), underestimated it in 25 patients (8.8%) and overestimated it in 113 patients (39.6%). OACs were used in 89.8% of patients whose stroke risk was correctly estimated, 72.0% of those whose stroke risk was underestimated, and 84.1% of patients whose health status was overestimated. After multivariable adjustment, the underestimation of stroke risk was independently associated with less use of OACs (adjusted odds ratio 0.23, 95% CI 0.061-0.85, P=0.028).
Conclusions: In this cohort study, physician underestimation of stroke risk was not rare and associated with less use of OACs.