Abstract WP185: Cryptogenic Stroke and Patent Foramen Ovale: Posterior Circulation Strokes Are More Common In Men Than In Women

Abstract

Background Stroke databanks have consistently found a high ratio of anterior circulation (AC) to posterior circulation (PC) strokes without significant differences when compared for vascular risk factors, stroke etiology, treatments and outcome. One study suggested that there was a deviation from this consistent observation when comparing men and women with cryptogenic stroke (CS) and patent foramen ovale (PFO). We tested these associations using the RoPE database. Methods The Risk of Paradoxical Embolism (RoPE) Study is an international collaboration of 12 merged cohort studies of patients with CS and known PFO status (n=3674). This analysis was restricted to those subjects in the RoPE database with index strokes in the AC or PC (excluding both or unknown) from the 7 databases that had data for CS with, and without, PFO. We compared the effect of sex on infarct location among patients with versus without PFO. We used generalized linear mixed models to examine whether PFO status modified the gender effect on infarct location adjusting for study cohort as a random effect. Results Among cryptogenic stroke patients both with and without PFO, AC strokes were more common (61%) than PC overall (n=1535). Among patients with PFO, PC stroke was higher in men than in women (50% vs. 33%, OR 2.23, 95% CI: 1.58-3.13). This gender effect was attenuated in those without PFO (38% vs. 31%; OR 1.32, 95% CI: 0.98-1.77). The gender-by-PFO-status interaction was significant (p= 0.0224) and was highly consistent across study cohorts. Conclusions These data confirm that males with CS and PFO contravene the otherwise consistent pattern that AC strokes are more commonly observed than PC strokes in stroke populations. The potential mechanisms underlying this interaction between gender and PFO-status remain to be elucidated.