Impact of gender-age interaction on the outcome of ischemic stroke in an Italian cohort of patients treated according to a standardized clinical pathway

BACKGROUND: Stroke outcome has been reported as worse in women, especially in terms of disability. As for mortality, the data are conflicting, with some reports suggesting a female advantage. Our objective was to explore such issues in an Italian cohort of patients managed by a standardized clinical pathway (CPW) and, as such, homogeneous in terms of clinical management. METHODS: Data from a cohort of 1993 patients (987 women and 1006 men) with first-ever ischemic stroke, consecutively referred to an in-hospital Clinical Pathway Program from January 1, 2001 to December 31, 2009, were retrospectively analyzed. The relationship between female gender and one-month outcome was assessed with adjustment for age, stroke severity and premorbid disability. RESULTS: The outcome was worse in women in terms of disability (age-adjusted odds ratio 2.03, 95% CI 1.69-2.46), while no difference was found for mortality. In multivariate models, female gender turned out to be associated with a lower case-fatality rate (adjusted hazard ratio 0.65, 95% CI 0.48-0.89, P=0.007), whereas the odds ratio for disability decreased but remained significant (OR 1.30; 95% CI 1.01-1.69). We found a significant interaction between gender and age in the case-fatality rate, and a female survival advantage was apparent only below 50 years. CONCLUSIONS: Our study confirms the excess risk of disability after stroke in women, although it is mostly explained by the occurrence of the most severe clinical syndromes. As for mortality, female gender seems to play a protective role, at least in the short-term and in younger patients.