One-year case fatality rate following stroke in the Mashhad Stroke Incidence Study: a population-based study of stroke in Iran

Abstract

Background: In developing countries, there are few comprehensive studies of mortality following stroke.

Aims and/or hypothesis: We aimed to determine the one-year case fatality rate following stroke and to identify factors associated with death in a population-based stroke incidence study in Iran.

Methods: Six hundred eighty-four patients who had suffered a stroke between November 21, 2006, and November 20, 2007, and were recruited to the Mashhad Stroke Incidence Study were followed up at one-year. Most patients were seen in an outpatient visit. When patients had died, a verbal autopsy was conducted by telephone with the next of kin.

Results: A total of 226 (34·3%) patients died during the first year following stroke. The cumulative one-year case fatality rate was 30·6% following ischemic stroke and 53·0% following hemorrhagic stroke (55·8% after intracerebral hemorrhage and 35·7% after subarachnoid hemorrhage). The majority of these deaths occurred in the first 28 days after stroke (17·7% with ischemic and 43·0% with hemorrhagic stroke). Factors associated with greater mortality at one-year (excluding those who died during the first week) were hemorrhagic stroke [hazard ratio (HR) 3·99; 95% confidence interval 1·90-8·37], age (HR 1·05; 95% confidence interval 1·03-1·08), previous transient ischemic attack (HR 2·45; 95% confidence interval 1·00-5·99), and National Institutes of Health Stroke Scale on admission (HR 1·14; 95% confidence interval 1·10-1·17).

Conclusion: Despite the younger age of stroke occurrence in Iran, the one-year case fatality rate following stroke is similar to that reported in developed countries.

Keywords: Iran; Mashhad; case fatality; epidemiology; mortality; stroke.