Temporal Trends in Population Rates of Incident Atrial Fibrillation and Atrial Flutter Hospitalizations, Stroke Risk, and Mortality Show Decline in Hospitalizations

Background: Hospitalization for nonvalvular atrial fibrillation (NVAF) is common and results in substantial cost burden. Current national data trends for the incidence, stroke risk profiles, and mortality of hospitalization for NVAF and atrial flutter (AFL) are sparse. Methods: The Canadian Institute of Health Information Discharge Abstract Database was used to identify patients >= 20 years with incident NVAF/AFL (NVAF, ICD-9 code 427.3 or ICD-10 I48) in any diagnosis field from 2006 to 2015 in Canada, except Quebec. National and provincial trends in rate over time (rate ratio, 95% confidence interval [CI]) were calculated for age-sex standardized hospitalizations. Trends in stroke risk profiles and in-hospital mortality rates adjusted for stroke risk factors were also calculated. Results: A total of 578,947 patients were hospitalized with incident NVAF/AFL. The median age was 77 years (interquartile range: 68-84), 82% were >= 65 years, 54% were men, 54% had a CHADS2 >= 2, and 69% had a CHA2DS2-Vasc >= 3. The overall age- and sex-standardized rate of NVAF/AFL hospitalization was 315 per 100,000 population and declined by 2% per year (P < 0.001). There was an annual rate decline in NVAF/AFL hospitalizations in every province. The majority of hospitalized patients are at high risk of stroke, and this risk remained unchanged. The average adjusted in-hospital mortality was 8.80 per 100 patients 95% CI, 8.80-8.81 with a 2% annual decline in rate (P < 0.001). Conclusion: Between 2006 and 2015, we found national and provincial hospitalization rates for incident NVAF/AFL are declining. The majority of patients are at high risk for stroke. In-hospital mortality has declined but remains substantial.