Population-based analysis of the impact of expanding the time window for acute stroke treatment

Currently, a major focus on expanding acute ischemic stroke treatment opportunities centers on the development of drugs and devices with longer time windows for use. We sought to determine the time intervals within which stroke patients present to establish whether time window expansion will translate into more treatment.

Data were derived from the Brain Attack Surveillance in Corpus Christi project, a population-based stroke surveillance study in an urban, southeast Texas county. This community does not contain an academic medical center, thus providing a "real-world" setting to capture patient arrival times. Onset time was recorded from the chart according to a prespecified methodology.

From January 2000 to June 2005, 2347 patients with acute ischemic stroke were validated. The mean age was 71 years, and 53% were female. Thirty-one percent presented within 3 hours of symptom onset; 13% between 3 and 6 hours; and 15% between 6 and 12 hours. Forty-one percent presented beyond 12 hours from symptom onset. Nearly half of patients with moderate and severe strokes presented in the 0- to 3-hour time window, whereas only 28% of mildly affected patients presented early.

This population-based study provides estimates of time to presentation in a representative community without tertiary referral bias. These data are useful for planning acute stroke therapy interventions and suggest that in addition to developing therapies with expanded time windows, research resources should also be devoted to reducing hospital presentation delays.