Supplementary results for stroke, timing of atrial fibrillation diagnosis, and risk of death

Objective:  To evaluate the prognosis of ischemic stroke
patients according to the timing of an atrial fibrillation (AF) diagnosis,
we created an inception cohort of incident stroke events and compared the
risk of death between stroke patients with a) sinus rhythm;
b) known atrial fibrillation (KAF); and c) AF diagnosed after
stroke (AFDAS).  Methods:  We utilized the Penn
AF Free study to create an inception cohort of patients with incident
stroke.  Mortality events were identified after linkage
with the National Death Index through June 30, 2017.  We
also evaluated initiation of anticoagulants and antiplatelets across the
study duration.  Cox proportional hazards models
evaluated associations between stroke subtypes and death.
Results:  We identified 1,489 individuals who developed
an incident ischemic stroke event:  985 did not develop
AF at any point during the study period, 215 had KAF before stroke, 160
had AF detected ≤6 months after stroke and 129 had AF
detected >6 months after stroke.  After a median
follow-up of 4.9 [IQR 1.9, 6.8] years, 686 deaths
occurred.  The annualized mortality rate was 8.8% in the
stroke, no AF group; 12.2% in the KAF group, 15.8% in the AFDAS ≤6 months;
and 12.7% in the AFDAS > 6 months. Patients in the AFDAS ≤6 months
had the highest independent risk of all-cause mortality even after
multivariable adjustment for demographics, clinical risk factors and the
use of antithrombotic therapies [HR 1.62 (1.22,
2.14)].  Compared to the stroke, no AF group, those with
KAF had a higher mortality risk that was rendered non-significant after
adjustment.   Conclusions: The AFDAS group had the
highest risk of death, which was not explained by comorbidities or use of
antithrombotic therapies.