Trajectory of cognitive decline before and after incident arrhythmias in older adults: A 16-year population-based longitudinal cohort study

INTRODUCTION: The temporal pattern of cognitive decline before and after incident arrhythmias remains largely unknown. METHODS: This population-based cohort study included 6,494 participants (mean age: 62.9 ± 9.4 years) from the English Longitudinal Study of Ageing. Participants underwent a cognitive assessments at baseline and at least one subsequent time point. RESULTS: During a median follow-up of 12 years, 628 individuals were diagnosed with incident arrhythmias. Overall, the annual rate of cognitive decline before arrhythmia diagnosis among individuals who experienced incident arrhythmias was similar to that of participants who were free of arrhythmias throughout follow-up. No short-term cognitive decline was observed in participants with arrhythmia diagnosis after the event. Individuals with incident arrhythmias demonstrated a faster decline in global cognition (−0.042 standard deviation/year; 95% confidence interval: −0.065 to −0.019) over the years after arrhythmia diagnosis than before the event. DISCUSSION: Incident arrhythmias are associated with accelerated cognitive decline after, but not before, the event. Highlights: The annual rate of cognitive decline before arrhythmia diagnosis among individuals who experienced incident arrhythmias was similar to that of participants who were free of arrhythmias throughout follow-up. Incident arrhythmias were not associated with an acute decrease in global cognition, memory, or executive function at the time of the event. The rate of decline in global cognition and memory significantly accelerated over the years after arrhythmia diagnosis. Preventing arrhythmias may be important in reducing long-term cognitive decline.