Is the effect of sex on post-thrombectomy outcomes in acute ischemic stroke age-dependent? Results from an international prospective registry (EVA-TRISP)

We aimed to investigate the effect of sex on clinical outcomes after endovascular treatment (EVT) in ischemic stroke patients and whether this effect is age dependent. We used data from EVA-TRISP, a multicentre registry of consecutive EVT patients. Primary outcome was the 90-day modified Rankin Scale (mRS) score, analysed with unadjusted and adjusted mixed model ordinal regression. We compared women with men and assessed the interaction between age and sex. We assessed age both as a continuous variable and dichotomized at the population median. In total, 12,915 EVT patients were included for the current study (median age 74 [IQR 64–82] years, 6,251 [48.4%] women). Female patients were older (77 [IQR 67–84] vs 72 [IQR: 62–80], p < 0.001) and had a higher median baseline NIHSS (15 [IQR 9–19] vs 14 [IQR 8–19], p < 0.001). Female sex was associated with worse functional outcome in the unadjusted analysis (cOR 1.22, 95%CI:1.14–1.29) but not in the adjusted analysis (acOR 1.02, 95%CI:0.95–1.09). We found no significant interaction between age and sex when assessing age as a continuous variable ( p = 0.08), but observed a significant interaction when dichotomizing age ( p = 0.01). In patients aged 74 or younger, women had worse outcomes than men (acOR 1.10, 95%CI:1.003–1.20) while sex was not associated with functional outcome in older patients (acOR 0.93, 95%CI:0.85–1.02). We did not find clear evidence that the effect of sex on post-EVT outcomes is modified by age when using age as continuous variable, but observed a worse outcome in women in patients aged 74 or younger.