Trends in the rates of hospitalizations for acute stroke among patients over 90 years of age with atrial fibrillation in the United States: from 2005 to 2014

Background Acute stroke (AS) rates in patients over 90 years of age (very elderly) with atrial fibrillation (AF) in the United States (US) are not known. We assessed trends in hospitalizations for AS among very elderly with AF in the US from 2005 to 2014. Methods We used the nationwide inpatient sample (NIS) from the USA; 2005-2014. AF and AS diagnoses were abstracted using international classification of diseases, 9(th) Revision, clinical modification (ICD-9-CM) codes. Results From 2005 to 2014, 3,606,073 hospitalizations of very elderly with AF were reported. Of these, 188,948 hospitalizations (141,822 hospitalizations in women and 47,126 hospitalizations in men) had AS as the primary diagnosis. Age adjusted AS hospitalizations increased in the total cohort (3217/million in 2005 to 3871/million in 2014), in women (3540/million in 2005 to 4487/million in 2014) and in men (2490/million in 2005 to 3173/million in 2014) (P< 0.001). Anticoagulation rates increased in women (8% in 2005 to 19.9% in 2014) and in men (8.9% in 2005 to 21.6% in 2014). AS rates, though numerically lower than the total cohort, showed an increasing trend in anticoagulated patients as well (all anticoagulated patients: 212/million in 2005 to 513/million in 2014; anticoagulated women: 224/million in 2005 to 529/million in 2014, anticoagulated men: 184/million in 2005 to 518/million in 2014). Conclusions There is an increasing trend in AS hospitalizations among nonagenarians with AF in the US despite improving utilization of anticoagulants in this patient population. The etiologies driving this alarming trend are unclear and require further study.