Neurology

Plasma brain-derived tau tracks infarct growth and outcomes after ischemic stroke

In 502 acute ischemic stroke patients, higher admission plasma brain-derived tau (BD-tau) correlated with larger early injury and final infarct volumes. Rising BD-tau from admission to day 2 tracked infarct growth and remained higher to day 7 in patients with secondary ischemic events. After thrombectomy, patients with complete recanalization had a smaller BD-tau rise than those with incomplete recanalization, suggesting sensitivity to treatment success. Across a 519-patient multicenter cohort, BD-tau outperformed MRI-derived final infarct volume for predicting functional outcomes up to 36 months. In a phase 3 nerinetide trial substudy, BD-tau mediated the recanalization–outcome association and increased less with nerinetide than placebo. These findings position BD-tau as a candidate surrogate endpoint for ischemic brain injury and therapeutic response in stroke trials. 1

Five-year poststroke dementia risk estimated from routine clinical variables

The STROKOG collaboration pooled 2,663 stroke survivors from 12 international cohorts to develop a 5-year poststroke dementia risk model. Predictors were age, sex, education, prior stroke, diabetes, baseline stroke severity, two interactions, and national health expenditure level. The model showed strong discrimination in the development dataset (C-index 0.81) and acceptable performance across cohorts by internal-external cross-validation. Performance was higher in recent and European cohorts, with modest risk overestimation in Asian cohorts, indicating a need for regional recalibration. An Excel-based calculator allows bedside estimation of 5-year dementia risk using standard clinical and stroke-severity data. This tool can support poststroke counseling, follow-up intensity decisions, and enrichment of dementia-prevention trials. 2

U-shaped association between admission systolic BP and outcomes after EVT

This EVA-TRISP cohort included 10,963 patients undergoing endovascular thrombectomy with documented admission systolic blood pressure (SBP). Functional outcome, mortality, and 24-hour NIHSS showed a U-shaped association with SBP, with the best outcomes around 150 mm Hg. Below 150 mm Hg, each 10 mm Hg SBP decrease increased odds of poor outcome and mortality; above 150 mm Hg, each 10 mm Hg increase did the same. Higher admission SBP was linearly associated with symptomatic intracranial hemorrhage risk. In EVT-only patients without IV thrombolysis, the association between higher SBP and worse outcomes was less evident. These data support targeting admission SBP near 150 mm Hg for EVT candidates, with caution at both lower and higher levels, especially when IVT is used. 3

Hearing aid use associated with lower dementia risk in older adults

Using ASPREE data, investigators emulated a target trial in dementia-free older adults with self-reported moderate hearing impairment and no prior hearing aid use. Over 7 years, hearing aid prescription produced similar mean cognition trajectories but a lower dementia risk than no prescription (risk ratio 0.67). Hearing aid prescription also reduced the composite risk of cognitive impairment, with the estimate at the threshold of statistical significance. Higher frequency of hearing aid use was associated with lower risks of dementia and cognitive impairment. Residual confounding cannot be excluded, but findings support treating hearing loss as a potential dementia-prevention strategy. The results justify long-term randomized trials and proactive counseling about hearing evaluation and hearing aid uptake. 4