Incidence, comorbidity, case fatality and readmission of hospitalized stroke patients in Canada

BACKGROUND: Stroke is a leading Cause of death and disability, and poses a significant burden of care for those who Survive. OBJECTIVES: To estimate the incidence of hospitalization for stroke and describe the impact of age, sex and comorbidity on in-hospital mortality, length of stay and readmission rates. METHODS: Health insurance numbers were used to link acute care hospitalizations across Canada in 1999/2000 for stroke patients with no discharges for a stroke within the preceding five years. Patients were followed up for one year from the date of their initial admission. RESULTS: The numbers of men (15,367) and women (16,740) in the study were similar. The incidence of all types of stroke (International Classification of Diseases, ninth revision, codes 430, 431 and 434/436) for hospitalized men and women was 14.4 per 10,000, with a 15-fold rise from 8.7 for the age group of 45 to 64 years to 131.9 per 10,000 for the age group 80 years and older. For the index episode, stroke patients spent an average of 21.0 days in the hospital, and 18.2% died in the hospital within 28 days. Of those who survived the first episode, 10.3% were readmitted to the hospital within one year with a recurrent stroke, and overall 37.1% were readmitted for any cause (including stroke). Among these stroke patients, hypertension was codiagnosed in 35%; diabetes in 17%; arrhythrma in 15%; ischemic heart disease in 13.6%; and congestive heart failure in 5%. CONCLUSIONS: Hospital records linked by patient identification can produce more accurate national estimates of patients hospitalized with stroke than any current countrywide Surveillance system.