Sex-Related Differences in Clinical Features, Neuroimaging, and Long-Term Prognosis After Transient Ischemic Attack

Background and purpose: Differences in sex in the incidence, presentation, and outcome of events after ischemic stroke have been studied in depth. In contrast, only limited data are available after transient ischemic attack (TIA). We aim to assess sex-related differences in the presentation, cause, neuroimaging features, and predictors of long-term prognosis in patients with TIA.

Methods: We carried out a prospective cohort study of consecutive patients with TIA from January 2006 to June 2010. Nondefinitive TIA events were defined by the presence of isolated atypical symptoms. The risk of stroke recurrence (SR) and composite of major vascular events were stratified by sex after a median follow-up time of 6.5 (interquartile range, 5.0-9.6) years.

Results: Among the 723 patients studied, 302 (41.8%) were female and 79 (10.9%) suffered a nondefinitive TIA event. Vascular territory diffusion-weighted imaging patterns (odds ratio, 1.61 [95% CI, 0.94-2.77]), and nondefinitive TIA events (odds ratio, 2.66 [95% CI, 1.55-4.59]) were associated with women, whereas active smoking (odds ratio, 0.30 [95% CI, 0.15-0.58]) and large artery atherosclerosis causes (odds ratio, 0.50 [95% CI, 0.29-0.83]) were related to men. The risk of SR was similar in both sexes (12.6% [95% CI, 8.9-16.3] for women versus 14.3% [95% CI, 11.0-17.6] for men). In contrast, the risk of major vascular events was significantly lower in women than in men (17.5% [95% CI, 13.2-21.8] versus 23.8% [95% CI, 19.7-27.9]). In both sexes, after adjusting for age, large artery atherosclerosis was associated with SR (hazard ratio, 3.22 [95% CI, 1.42-7.24] and hazard ratio, 2.00 [95% CI, 1.14-3.51]). In a Kaplan-Meier analysis, females with positive diffusion-weighted imaging (P=0.014) and definitive TIA (log-rank test P=0.022) had a significantly higher risk of SR.

Conclusions: Despite similar risks of SR, there were sex-related differences in baseline characteristics, presenting symptoms, patterns of acute ischemic lesions, cause, and outcomes. These findings encourage further research into optimal preventive strategies that take into account these differences.