How baseline severity affects efficacy and safety outcomes in acute ischemic stroke intervention trials

Bringing door-to-needle times within the European benchmarks results in better stroke patients outcomes in a spoke hospital from the Apulian Region

INTRODUCTION

Door-to-needle time (DNT) is a key factor in acute stroke treatment success. We retrospectively analysed the effects of a new protocol aimed at reducing treatment delays in our single-centre observational series over a 1-year period (from October 1st 2021 to September 30th 2022).

METHODS

The time frame was divided into two semesters as a new protocol was started at the beginning of the second semester to ensure a rapid evaluation, imaging, and intravenous thrombolysis in all stroke patients attending our spoke-hospital serving 200,000 inhabitants. Logistics and outcome measures were obtained for each patient and compared before and after implementation of the new protocol.

RESULTS

A total of 215 patients with ischemic stroke attended our hospital within a 1-year period (109 in the first semester, 96 in the second semester). Seventeen percent and 21% of all patients underwent acute stroke thrombolysis in the first and second semesters, respectively. DNTs were strongly reduced in the second semester (from 90 to 55 min), bringing this value below the Italian and European benchmarks. This resulted in better short-term outcomes (an average of 20%) as measured by both Δ NIHSS scores at 24 h and at discharge with respect to baseline.

Predictors of Neurological and Functional Recovery in Patients with Moderate to Severe Ischemic Stroke: The EPICA Study

BACKGROUND

Improving our knowledge about the impact of restorative therapies employed in the rehabilitation of a stroke patient may help guide practitioners in prescribing treatment regimen that may lead to better post-stroke recovery and quality of life.

AIMS

To evaluate the neurological and functional recovery for 3 months after an acute ischemic stroke occurred within previous 3 months. To determine predictors of recovery.

DESIGN

Prospective observational registry. Population. Patients having suffered acute moderate to severe ischemic stroke of moderate to severe intensity within the previous 3 months with National Institutes of Health Stroke Scale (NIHSS) score from 10 to 20, 24 hours after arrival at emergency room (ER).

METHODS

All prespecified variables (sociodemographic and clinical data, lifestyle recommendations, rehabilitation prescription, and neurological assessments) were assessed at three visits, i.e., baseline (D0), one month (M1), and three months (M3).

RESULTS

Out of 143 recruited patients, 131 could be analysed at study entry within 3 months after stroke onset with a mean acute NIHSS score of 14.05, decreased to 10.8 at study baseline. Study sample was aged 64.9 ± 13.8 years, with 49.2% of women. Neurorehabilitation treatment was applied to 9 of 10 patients from the acute phase and for three months with different intensities depending on the centre. A large proportion of patients recovered from severe dependency on activities of daily living (ADL) at D0 to a mild or moderate disability requiring some help at M3: mean NIHSS = 10.8 to 5.7; median modified Rankin Scale (mRS) = 4 to 3; Barthel index (BI) = 40 to 70; all p values < 0.001. Multivariate analyses integrating other regression variables showed a trend in favour of rehabilitation and revascularization therapies on recovery although did not reach statistical significance and that the positive predictors of recovery improvement were baseline BI score, time to treatment, and dietary supplement MLC901 (NurAiD™II). A larger percentage of patients with more severe stroke (NIHSS > 14) who received MLC901 showed above median improvements on mRS compared to control group at M1 (71.4% vs. 29.4%; p = 0.032) and M3 (85.7% vs. 50%; p = 0.058). Older subjects and women tend to have less improvement by M3.

CONCLUSIONS

Our study in patients with moderate to severe stroke shows overall recovery on neurological and functional assessments during the 3 months of study observation. Apart from demonstrating traditional "non-modifiable" predictors of outcome after stroke, like age, sex, and stroke severity, we also detected association between the use of dietary supplement MLC901 and recovery.

Prognostic Factors and Pattern of Long-Term Recovery with MLC601 (NeuroAiD™) in the Chinese Medicine NeuroAiD Efficacy on Stroke Recovery - Extension Study

BACKGROUND

The Chinese Medicine NeuroAiD Efficacy on Stroke recovery - Extension (CHIMES-E) study is among the few acute stroke trials with long-term outcome data. We aimed to evaluate the recovery pattern and the influence of prognostic factors on treatment effect of MLC601 over 2 years.

METHODS

The CHIMES-E study evaluated the 2 years outcome of subjects aged ≥18 years with acute ischemic stroke, National Institutes of Health Stroke Scale (NIHSS) score 6-14, pre-stroke modified Rankin Scale (mRS) score ≤1 included in a multicenter, randomized, double-blind, placebo-controlled trial of MLC601 for 3 months. Standard stroke care and rehabilitation were allowed during follow-up with mRS score being assessed in-person at month (M) 3 and by telephone at M1, M6, M12, M18 and M24.

RESULTS

Data from 880 subjects were analyzed. There was no difference in baseline characteristics between treatment groups. The proportion of subjects with mRS score 0-1 increased over time in favor of MLC601 most notably from M3 to M6, thereafter remaining stable up to M24, while the proportion deteriorating to mRS score ≥2 remained low at all time points. Older age (p < 0.01), female sex (p = 0.06), higher baseline NIHSS score (p < 0.01) and longer onset to treatment time (OTT; p < 0.01) were found to be predictors of poorer outcome at M3. Greater treatment effect, with more subjects improving on MLC601 than placebo, was seen among subjects with 2 or more prognostic factors (OR 1.65 at M3, 1.78 at M6, 1.90 at M12, 1.65 at M18, 1.39 at M24), especially in subjects with more severe stroke or longer OTT.

CONCLUSIONS

The sustained benefits of MLC601 over 2 years were due to more subjects improving to functional independence at M6 and beyond compared to placebo. Selection of subjects with poorer prognosis, particularly those with more severe NIHSS score and longer OTT delay, as well as a long follow-up period, may improve the power of future trials investigating the treatment effect of neuroprotective or neurorestorative therapies.

Non-Invasive Brain Stimulation to Enhance Post-Stroke Recovery

Brain plasticity after stroke remains poorly understood. Patients may improve spontaneously within the first 3 months and then more slowly in the coming year. The first day, decreased edema and reperfusion of the ischemic penumbra may possibly account for these phenomena, but the improvement during the next weeks suggests plasticity phenomena and cortical reorganization of the brain ischemic areas and of more remote areas. Indeed, the injured ischemic motor cortex has a reduced cortical excitability at the acute phase and a suspension of the topographic representation of affected muscles, whereas the contralateral motor cortex has an increased excitability and an enlarged somatomotor representation; furthermore, contralateral cortex exerts a transcallosal interhemispheric inhibition on the ischemic cortex. This results from the imbalance of the physiological reciprocal interhemispheric inhibition of each hemisphere on the other, contributing to worsening of neurological deficit. Cortical excitability is measurable through transcranial magnetic stimulation (TMS) and prognosis has been established according to the presence of motor evoked potentials (MEP) at the acute phase of stroke, which is predictive of better recovery. Conversely, the lack of response to early stimulation is associated with a poor functional outcome. Non-invasive stimulation techniques such as repetitive TMS (rTMS) or transcranial direct current stimulation (tDCS) have the potential to modulate brain cortical excitability with long lasting effects. In the setting of cerebrovascular disease, around 1000 stroke subjects have been included in placebo-controlled trials so far, most often with an objective of promoting motor recovery of the upper limb. High frequency repetitive stimulation (>3 Hz) rTMS, aiming to increase excitability of the ischemic cortex, or low frequency repetitive stimulation (≤1 Hz), aiming to reduce excitability of the contralateral homonymous cortex, or combined therapies, have shown various effects on the functional disability score and neurological scales of treated patients and on the duration of the treatment. We review here the patients’ characteristics and parameters of stimulation that could predict a good response, as well as safety issues. At last, we review what we have learnt from experimental studies and discuss potential directions to conduct future studies.

Prognostic factors and treatment effect in the CHIMES study

BACKGROUND

Stroke trials often analyze patients with heterogeneous prognoses using a single definition of outcome, which may not be applicable to all subgroups. We aimed to evaluate the treatment effects of MCL601 among patients stratified by prognosis in the Chinese Medicine Neuroaid Efficacy on Stroke Recovery (CHIMES) study.

METHODS

Analyses were performed using data from the CHIMES study, an international, randomized, placebo-controlled, double-blind trial comparing MLC601 with placebo in patients with ischemic stroke of intermediate severity in the preceding 72 hours. All subjects with baseline data and the modified Rankin Scale (mRS) score at 3 months were included.

RESULTS

Data from 1006 subjects were analyzed. The predictive variables for mRS score greater than 1 at month 3 were age older than 60 years (P < .001), baseline National Institutes of Health Stroke Scale score 10-14 (P < .001), stroke onset to initiation of study treatment of more than 48 hours (P < .001), and female sex (P = .026). A higher number of predictors was associated with poorer mRS score at month 3 for both placebo (P < .001) and treatment (P < .001) groups. The odds ratio (OR) for achieving a good outcome increased with the number of predictors and reached statistical significance in favor of MLC601 among patients with 2 to 4 predictors combined (unadjusted OR = 1.44, 95% confidence interval, 1.02-2.03; adjusted OR = 1.60, 95% confidence interval, 1.10-2.34).

CONCLUSIONS

Age, sex, baseline National Institutes of Health Stroke Scale score, and time to first dose are predictors of functional outcome in the CHIMES study. Stratification by prognosis showed that patients with 2 or more predictors of poorer outcome have better treatment effect with MLC601 than patients with single or no prognostic factor. These results have implications on designing future stroke trials.

Baseline characteristics and treatment response of patients from the Philippines in the CHIMES study

BACKGROUND

The CHIMES Study compared MLC601 with placebo in patients with ischemic stroke of intermediate severity in the preceding 72 h. Sites from the Philippines randomized 504 of 1099 (46%) patients in the study. We aimed to define the patient characteristics and treatment responses in this subgroup to better plan future trials.

METHODS

The CHIMES dataset was used to compare the baseline characteristics, time from stroke onset to study treatment initiation, and treatment responses to MLC601 between patients recruited from Philippines and the rest of the cohort. Treatment effect was analyzed using end-points at month 3 as described in the primary publication, that is, modified Rankin Score, National Institutes of Health Stroke Scale, and Barthel Index.

RESULTS

The Philippine cohort was younger, had more women, worse baseline National Institutes of Health Stroke Scale, and longer time delay from stroke onset to study treatment compared with the rest of the cohort. Age (P = 0·003), baseline National Institutes of Health Stroke Scale (P < 0·001), and stroke onset to study treatment initiation (P = 0·016) were predictors of modified Rankin Score at three-months. Primary analysis of modified Rankin Score shift was in favor of MLC601 (adjusted odds ratio 1·41, 95% confidence interval 1·01-1·96). Secondary analyses were likewise in favor of MLC601 for modified Rankin Score dichotomy 0-1, improvement in National Institutes of Health Stroke Scale (total and motor scores), and Barthel Index.

CONCLUSIONS

The treatment effects in the Philippine cohort were in favor of MLC601. This may be due to inclusion of more patients with predictors of poorer outcome.