Objectives To investigate whether an imaging measure of corticospinal tract (CST) injury in the acute phase can predict motor outcome at 3 month in comparison to clinical assessment of initial motor impairment. Methods A two-site prospective cohort study followed up a group of first-ever ischemic stroke patients using the Upper-Extremity Fugl-Meyer (UE-FM) Scale to measure the motor impairment in the acute phase and at 3 months. A weighted CST lesion load (wCST-LL) was calculated by overlaying the patient’s lesion map on MRI with a probabilistic CST constructed from healthy control subjects. Regression models were fit to assess the predictive value of wCST-LL and compared with initial motor impairment. Results 76 patients (37 from cohort 1 and 39 from cohort 2) completed the study. wCST-LL correlated motor impairment at 3 months measured by UE-FM scale, similar to the clinical assessment of initial motor impairment in both cohort 1 (R2=0.69 vs. R2=0.67, p=0.43) and cohort 2 (R2=0.69 vs. R2=0.62, p=0.25). In the severely impaired subgroup (defined as UE-FM ≤10 at baseline), wCST-LL correlated outcomes significantly better than clinical assessment (R2=0.47 vs. R2=0.11, p=0.03). In the non-severely impaired subgroup, stroke patients recovered approximately 70% of their maximal recovery potential. All stroke patients in both cohorts had poor motor outcomes at 3 months (defined as UE-FM≤25) when wCST-LL was ≥7.0 cc (positive predictive value is 100%). Interpretation wCST-LL, a potential imaging biomarker from the acute phase, can predict post-stroke motor outcomes at 3 months, especially in patients with severe impairment at baseline.

IntroductionPatients with stroke-like symptoms may be underutilising emergency medical services and avoiding hospitalisation during the COVID-19 pandemic. We investigated a decline in admissions for stroke and transient ischaemic attack (TIA) and emergency department (ED) stroke alert activations.MethodsWe retrospectively compiled total weekly hospital admissions for stroke and TIA between 31 December 2018 and 21 April 2019 versus 30 December 2019 and 19 April 2020 at five US tertiary academic comprehensive stroke centres in cities with early COVID-19 outbreaks in Boston, New York City, Providence and Seattle. We collected available data on ED stroke alerts, stroke severity using the National Institutes of Health Stroke Scale (NIHSS) and time from symptom onset to hospital arrival.ResultsCompared with 31 December 2018 to 21 April 2019, a decline in stroke/TIA admissions and ED stroke alerts occurred during 30 December 2019 to 19 April 2020 (p trend <0.001 for each). The declines coincided with state stay-at-home recommendations in late March. The greatest decline in hospital admissions was observed between 23 March and 19 April 2020, with a 31% decline compared with the corresponding weeks in 2019. Three of the five centres with 2019 and 2020 stroke alert data had a 46% decline in ED stroke alerts in late March and April 2020, compared with 2019. Median baseline NIHSS during these 4 weeks was 10 in 2020 and 7 in 2019. There was no difference in time from symptom onset to hospital arrival.ConclusionAt these five large academic US hospitals, admissions for stroke and TIA declined during the COVID-19 pandemic. There was a trend for fewer ED stroke alerts at three of the five centres with available 2019 and 2020 data. Acute stroke therapies are time-sensitive, so decreased healthcare access or utilisation may lead to more disabling or fatal strokes, or more severe non-neurological complications related to stroke. Our findings underscore the indirect effects of this pandemic. Public health officials, hospital systems and healthcare providers must continue to encourage patients with stroke to seek acute care during this crisis.

Metabolic syndrome is a cluster of cardiovascular risk factors defined by the presence of abdominal obesity, glucose intolerance, hypertension and/or dyslipidemia. It is a major public health epidemic worldwide, and a known risk factor for the development of cognitive dysfunction and dementia. Several studies have demonstrated a positive association between the presence of metabolic syndrome and worse cognitive outcomes, however, evidence of brain structure pathology is limited. Diffusion tensor imaging has offered new opportunities to detect microstructural white matter changes in metabolic syndrome, and a possibility to detect associations between functional and structural abnormalities. This review analyzes the impact of metabolic syndrome on white matter microstructural integrity, brain structure abnormalities and their relationship to cognitive function. Each of the metabolic syndrome components exerts a specific signature of white matter microstructural abnormalities. Metabolic syndrome and its components exert both additive/synergistic, as well as, independent effects on brain microstructure thus accelerating brain aging and cognitive decline.