Door-to-Door Capture of Incident and Prevalent Stroke Cases in Durango, Mexico

Abstract

Background and Purpose—: Stroke incidence and prevalence estimates in developing countries should include stroke cases not presenting to hospital. We performed door-to-door stroke case ascertainment in Durango Municipality, Mexico, to estimate stroke incidence and prevalence and to determine the error made by only ascertaining hospital cases. Methods—: Between September 2008 and March 2009, 1996 housing units were randomly sampled to screen for stroke in Durango Municipality residents 35 years of age and older. Field workers utilized a validated screening tool. Those screening positive were referred to a neurologist for history and examination and a head CT scan. Prevalence and cumulative incidence from the door-to-door surveillance were calculated and compared with previously reported hospitalization rates during the same defined time. Results—: Respondents included 2437 subjects from 1419 homes. The refusal rate was 3.8%. Twenty subjects had verified or probable stroke. The prevalence of probable or verified stroke was 7.7 per 1000 (95% CI, 4.3 per 1000–11.2 per 1000). Five patients had a stroke during the time of the hospital surveillance, yielding a cumulative incidence of 232.3 per 100 000 (95% CI, 27.8–436.9). Two of the 5 cases were captured by door-to-door surveillance but not by hospital surveillance. Conclusions—: This study provides the first community-based stroke prevalence and incidence estimates in Mexico. The wide confidence intervals, despite the large number of surveyed housing units, suggest the need for more advanced sampling strategies for stroke surveillance in the developing world.