Background: A patent foramen ovale (PFO) discovered in patients with cryptogenic stroke (CS) may be incidental or pathogenic. Recently, a Risk of Paradoxical Embolism (RoPE) score has been proposed to stratify patients by their PFO pathogenicity. Based on this score, the probability that a PFO is incidental (rather than pathogenic) increases with advancing age, deep stroke location, or the presence of cardiovascular risk factors (RF). Given that RF accumulate at a later age in women than in men, we hypothesize that there are gender differences in the variables used for RoPE score calculation.
Methods: The distribution of RF (history of hypertension, diabetes or stroke/TIA, current smoking, and age categories as defined in the original RoPE score publication) was compared by sex in the entire cohort of 1044 CS patients as well as within the groups with low (0-5) and high (7-10) RoPE scores (due to lacking information on cortical versus deep stroke location, we excluded all patients with a RoPE score of 6, since they could be either classified with low or high RoPE score depending on stroke location). Furthermore, for each patient we calculated the age impact ratio (AIR): the points assigned for the corresponding age category divided by the RoPE score. Gender comparisons of AIR were drawn in the entire cohort and within the RoPE score strata.
Results: Average age was 55.5 years and 635 patients (61%) were male. In the entire cohort, the distribution of age categories and RF as well as AIR did not differ between men and women. In the higher RoPE stratum (PFO likely pathogenic), women were younger than men (median, 38 years vs 45 years, P=0.036). The distribution of RF and the AIR did not differ between sexes. In the lower PFO stratum (PFO likely incidental), men were younger than women (median, 62 years vs 66 years, P=0.011). The AIR was lower in women than in men (mean, 0.24 vs 0.29, P=0.013). There were no gender differences in the distribution of RF.
Conclusions: There are significant gender differences in age among patients with CS and PFO, with women being younger than men in the higher RoPE stratum and vice versa in the lower RoPE stratum. More women than men are classified as having an incidental PFO because of their advancing age rather than the accumulation of RF.