Sex Differences in Outcome After Thrombectomy for Acute Ischemic Stroke are Explained by Confounding Factors

Abstract

Purpose The aim of this study was to analyze sex differences in outcome after thrombectomy for acute ischemic stroke in clinical practice in a large prospective multicenter registry. Methods Data of consecutive stroke patients treated with thrombectomy (June 2015–April 2018) derived from an industry-independent registry (German Stroke Registry–Endovascular Treatment) were prospectively analyzed. Multivariable binary logistic regression analyses were applied to determine whether sex is a predictor of functional independence outcome (defined as a modified Rankin scale [mRS] 0–2) 90 days after stroke. Results In total, 2316 patients were included in the analysis, 1170 (50.5%) were female and 1146 (49.5%) were male. Women were older (median age 78 vs. 72 years; p < 0.001) and more frequently had a prestroke functional impairment defined by mRS >1 (24.8% vs. 14.1%; p < 0.001). In unadjusted analyses, independent outcome at 90 days was less frequent in women (33.2%) than men (40.6%; p < 0.001). Likewise, mortality was higher in women than in men (30.7% vs. 26.4%; p = 0.024). In adjusted regression analyses, however, sex was not associated with outcome. Lower age, a lower baseline National Institutes of Health Stroke Scale score, a higher Alberta Stroke Program Early CT score, prestroke functional independence, successful reperfusion, and concomitant intravenous thrombolysis therapy predicted independent outcome. Conclusion Women showed a worse functional outcome after thrombectomy for acute ischemic stroke in clinical practice; however, after adjustment for crucial confounders sex was not a predictor of outcome. The difference in outcome thus appears to result from differences in confounding factors such as age and prestroke functional status.

The efficacy and risk factors of mechanical thrombectomy for the treatment of vertebrobasilar artery occlusion: a single center study

“…This current study further confirmed the important role of age in the unsatisfactory outcomes and in-hospital mortality. In practice, the age of patients in our study was relatively young compared with some other studies (23,24). Sojka et al reported that the mortality after 90 days was as high as 47.4 % in acute ischemic stroke patients aged more than 90 years old (25).…”

“…Our study also identified some other variables as risk factors of unsatisfactory outcomes in acute ischemic stroke patients caused by VBAO, however, these results were not statistically significant. Indeed, other reports have suggested that onsetto-recanalization time and being female may be risk factors of unsatisfactory outcomes in stroke patients (5,24). Further studies are needed to determine all the risk factors in the prognosis of acute ischemic stroke patients.…”

Sex differences in outcomes after mechanical thrombectomy for acute ischemic stroke in the ‘real world’: protocol for a systematic review and meta-analysis study

“…While, in the ‘real-world’ populations, studies exploring sex differences in functional outcomes after MT for large vessel occlusion strokes have controversial results. Some studies showed consistent results with the study of HERMES,4–6 but others demonstrated females are less likely to benefit from MT than males 7 8. A previous meta-analysis suggests that females have inferior 90-day clinical outcomes compared with males when undergoing endovascular thrombectomy for large-vessel occlusions, but both RCTs and observational studies were included 9.…”

Evaluating Outcome Prediction Models in Endovascular Stroke Treatment Using Baseline, Treatment, and Posttreatment Variables

“…The second set contained additional variables with a known association with outcome that are not always routinely captured in the clinical setting (“comprehensive models,” b models [1b–4b]). Variables included in the models were chosen a priori on the basis of known associations with clinical outcome from the literature; that is, no variable selection such as forward or backward selection was applied (see Table S2 and Figure 1 for model structure and detailed listing of variables included in each model 9,13–72 ). A multiplicative interaction term between nerinetide and alteplase was included in all models with treatment‐related variables (ie, models 2–4) because of the observed treatment effect modification of nerinetide by alteplase in the ESCAPE‐NA1 trial 9 .…”