Trends in hospitalizations and cost associated with stroke by age, United States 2003-2012

Background The disease burden associated with stroke by age is not well known. Aim To assess the trends in stroke hospitalizations and associated cost among adults aged ≥18 years by age groups in the United States. Methods The study population consisted of 2003-2012 adult hospitalizations from the National Inpatient Sample of the Healthcare Cost and Utilization Project. Subarachnoid hemorrhage, intracerebral hemorrhage, and acute ischemic stroke hospitalizations were identified by the principal diagnosis ICD-9-CM code. We estimated national hospitalization rates and inflation-adjusted hospital costs across five consecutive 2-year time intervals, stratified by seven age groups. Results Hospitalization rates for subarachnoid hemorrhage decreased significantly from 2003-2004 to 2011-2012 for ages 35-44 (relative percent change (RPC): -23%) and 45-54 (RPC: -22%), respectively. For intracerebral hemorrhage, the rates decreased significantly for ages ≥65 years. Acute ischemic stroke hospitalization rates increased significantly for ages 18-54 and decreased significantly for ages 65-84 years. The average per-hospitalization cost for subarachnoid hemorrhage increased 7-35% among all age groups, except those aged 65-74, and increased 10-29% for intracerabral hemorrhage except those aged 75-84, and increased 6-19% among all ages for acute ischemic stroke, respectively. Overall, the estimated total national cost increased 7% for subarachnoid hemorrhage, 10% for intracerebral hemorrhage, and 18% for acute ischemic stroke from 2003-2004 to 2011-2012. Conclusions From 2003 to 2012, subarachnoid hemorrhage and intracerabral hemorrhage stroke hospitalization rates declined across all age groups. While US acute ischemic stroke hospitalizations among ages 65-84 declined significantly, the hospitalization rates increased significantly among ages 18-54. The estimated hospital costs increased across all stroke subtypes during the study period.