RCT versus real-world cohorts: Differences in patient characteristics drive associations with outcome after EVT

Factors and outcomes associated with National Institutes of Health stroke scale scores in acute ischemic stroke patients undergoing thrombectomy in United States

BACKGROUND AND PURPOSE

The National Institutes of Health Stroke Scale (NIHSS) is the standard for assessing neurological deficits in acute ischemic stroke patients undergoing thrombectomy. However, data on NIHSS scores in patients undergoing thrombectomy at national-level studies in the United States are lacking.

METHODS

Acute ischemic stroke patients admitted between 2018 and 2021 were identified using ICD-10-CM codes from the Nationwide In-patient Sample, with NIHSS scores categorized into specific strata (0-9, 10-19, 20-29, 30-42). We analyzed the effect of NIHSS scores on in-hospital mortality, routine discharge without palliative care (based on discharge disposition), and length and costs of hospitalization after adjusting for potential confounders.

RESULTS

The NIHSS score strata among 108,990 acute ischemic stroke patients undergoing thrombectomy were: NIHSS score 0-9 (29.6 %), 10-19 (40.6 %), 20-29 (26.4 %), and 30-42 (3.4 %). Patients in the Midwest and West regions (adjusted odds ratio [adjusted OR] = 1.51, p = 0.002 and adjusted OR = 1.63, p < 0.001, respectively), those treated in rural hospitals (adjusted OR = 1.35, p = 0.009) and those who were self-pay (adjusted OR = 1.51, p = 0.048) had higher odds of being in higher NIHSS score strata. Patients in higher NIHSS score strata (NIHSS score 10-19, 20-29, and 30-42 had significantly lower odds of discharge home without palliative care (adjusted OR= 0.50, 0.32, and 0.22 respectively, all p < 0.001) and higher odds of in-hospital mortality (adjusted OR = 1.51, 2.30, and 3.80 respectively, all p < 0.001) compared to those in NIHSS score strata of 0-9. Patients in higher NIHSS score strata had significantly higher hospital stays and higher hospitalization costs.

CONCLUSIONS

We provide a comprehensive national-level analysis of NIHSS scores in acute ischemic stroke patients undergoing thrombectomy which may assist in understanding variations in outcomes and resource utilizations in United States.

Integrating a randomized controlled trial with a parallel observational cohort study in cervical spine surgery insights from the foraminotomy ACDF cost-effectiveness trial (FACET)

BACKGROUND CONTEXT

In most randomized controlled trials (RCT), data is primarily and often only available for individuals who have agreed to be randomized, with little, if any, consideration for those who elected not to participate.

PURPOSE

This study evaluated the value of including a concurrent observational cohort of patients who declined randomization in the Foraminotomy ACDF Cost-Effectiveness Trial (FACET-RCT) but still underwent anterior or posterior cervical surgery. The goal was to determine if the FACET-RCT results could be generalized by comparing baseline characteristics and clinical outcomes between the randomized trial and observational cohort.

STUDY DESIGN/SETTING

A nationwide RCT with a parallel observational cohort recruiting patients from routine care.

PATIENT SAMPLE

Between January 2016 and May 2020, 389 patients with cervical radiculopathy were screened, and 358 were eligible. Of these, 265 (74%) were randomized in the FACET-RCT for either posterior or anterior cervical surgery, while 80 (22%) opted out of randomization and were followed in an observational cohort. Only 13 (4%) patients declined participation in both FACET-RCT and cohort.

OUTCOME MEASURES

Demographic data was collected, and primary outcomes included treatment success, evaluated using the Odom criteria as well as reduction in arm pain, assessed with a Visual Analogue Scale (VAS) at 6 weeks, and every 6 months up to 2 years postsurgery. Secondary outcomes included VAS for neck pain, neck disability, work ability, quality of life, treatment satisfaction, and need for revision surgeries.

METHODS

Baseline characteristics were compared between the FACET-RCT and cohort using logistic regression. Primary and secondary outcomes were analyzed for differences between study designs using mixed-model analyses adjusted for confounders. The primary noninferiority endpoint of the FACET-RCT was evaluated in both the cohort and combined data from both cohort and FACET-RCT at 2 years of follow-up.

RESULTS

Patients in the cohort were slightly younger than those in the FACET-RCT (mean age of 48.4 versus 51.2 years; mean difference [MD], -2.5; 95% confidence interval [CI], -4.8 to -0.2; p=.04). In sub-analyses stratified by surgical approach (anterior vs. posterior surgery), fewer patients in the observational cohort who underwent posterior surgery reported severe neck pain at baseline compared to their counterparts in the FACET-RCT (OR, 0.38; 95% CI: 0.14 to 0.92; p=.04). No other significant baseline differences were found. No significant differences in treatment success (OR, 1.3; 95% CI: 0.3 to 6.0; p=.75) and arm pain reduction (MD, -3.9; 95% CI: -9.2 to 1.5; p=.16) were observed between study designs. The primary noninferiority endpoint was achieved in the combined data from both the cohort and FACET-RCT, with a narrower CI compared to the FACET-RCT alone, indicating a more robust result. Secondary outcomes were comparable between groups.

CONCLUSIONS

Randomization did not influence clinical outcomes for cervical surgery patients. Combining RCT with the observational cohort increased statistical power, external validity and robustness. Our findings support the value of observational methods as a complement to RCTs, especially when a large number of patients refuse RCT participation and high dropout and crossover rates are expected.

Do scoring systems help us to estimate prognosis after mechanical thrombectomy? Data from the German Stroke Registry

BACKGROUND

Numerous scoring systems have been developed to individualize estimation of functional outcome after endovascular thrombectomy (EVT) of acute ischemic stroke. The aim of our study was to assess their utility for clinical practice based on a large cohort from real-world care of EVT.

METHODS

For 13 082 patients included in the German Stroke Registry Endovascular Treatment (GSR-ET) (July 2015 to December 2021), we calculated the following prognostic tools: pre-interventional PRE-, Totaled Health Risks in Vascular Events - Endovascular therapy (THRIVE-EVT)- and Computed Tomography for Late Endovascular Reperfusion (CLEAR) scores and post-interventional MR PREDICTS@24 hours and BET-score. Area under the receiver operating characteristic curve (AUC) analyses in the total cohort and pre-defined subgroups were performed to determine each tool's prognostic value for good functional outcome (modified Rankin Scale (mRS) 0-2) and mortality at 90-day follow-up.

RESULTS

All pre-interventional tools achieved a moderate prognostic value for predicting good functional outcome (PRE: AUC (95% confidence interval): 0.757 (0.747-0.768), THRIVE-EVT: 0.751 (0.740-0.761), CLEAR: 0.731 (0.72-0.742)), had a higher predictive value than the admission National Institute of Health Stroke Scale ((NIHSS); 0.705 (0.694-0.716), all P<0.001), but were inferior to the NIHSS 24 hours after EVT (0.864 (0.855-0.872), all P<0.001). Predictive capacity for mortality was less accurate (AUC range: 0.697-0.729). Subgroup analyses revealed that the PRE-score was most robust at predicting good functional outcome, whereas the THRIVE-EVT score was superior in predicting mortality. Post-interventionally, MR PREDICTS@24 hours yielded high predictive accuracy for good functional outcome and mortality (both AUC >0.85), superior to 24-hour NIHSS for all subgroups, except patients <50 years of age.

CONCLUSION

Pre-interventional scoring tools predict functional outcome after EVT better than stroke severity alone. Post-interventionally, the MR PREDICTS@24 hours tool adds predictive value to the 24-hour NIHSS as a single prognostic feature. Multivariate prognostic tools incorporating (post-)procedural information enable individualization of prognosis assessment after EVT under routine-care conditions.

Associations of diabetes status and glucose measures with outcomes after endovascular therapy in patients with acute ischemic stroke: an analysis of the nationwide TREAT-AIS registry

Background

Hyperglycemia affects the outcomes of endovascular therapy (EVT) for acute ischemic stroke (AIS). This study compares the predictive ability of diabetes status and glucose measures on EVT outcomes using nationwide registry data.

Methods

The study included 1,097 AIS patients who underwent EVT from the Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke. The variables analyzed included diabetes status, admission glucose, glycated hemoglobin (HbA1c), admission glucose-to-HbA1c ratio (GAR), and outcomes such as 90-day poor functional outcome (modified Rankin Scale score ≥ 2) and symptomatic intracranial hemorrhage (SICH). Multivariable analyses investigated the independent effects of diabetes status and glucose measures on outcomes. A receiver operating characteristic (ROC) analysis was performed to compare their predictive abilities.

Results

The multivariable analysis showed that individuals with known diabetes had a higher likelihood of poor functional outcomes (odds ratios [ORs] 2.10 to 2.58) and SICH (ORs 3.28 to 4.30) compared to those without diabetes. Higher quartiles of admission glucose and GAR were associated with poor functional outcomes and SICH. Higher quartiles of HbA1c were significantly associated with poor functional outcomes. However, patients in the second HbA1c quartile (5.6-5.8%) showed a non-significant tendency toward good functional outcomes compared to those in the lowest quartile (<5.6%). The ROC analysis indicated that diabetes status and admission glucose had higher predictive abilities for poor functional outcomes, while admission glucose and GAR were better predictors for SICH.

Conclusion

In AIS patients undergoing EVT, diabetes status, admission glucose, and GAR were associated with 90-day poor functional outcomes and SICH. Admission glucose was likely the most suitable glucose measure for predicting outcomes after EVT.

Outcomes and risk factors for infection after endovascular treatment in patients with acute ischemic stroke

AIMS

Infection is a common complication following acute ischemic stroke (AIS) and significantly contributes to poor functional outcomes after stroke. This study aimed to investigate the effects of infection after endovascular treatment (post-EVT infection) on clinical outcomes and risk factors in patients with AIS.

METHODS

We retrospectively analyzed AIS patients treated with endovascular treatment (EVT) between January 2016 and December 2022. A post-EVT infection was defined as any infection diagnosed within 7 days after EVT. The primary outcome was functional independence, defined as a modified Rankin scale (mRS) score of 0-2 at 90 days. A multivariable logistic regression analysis was conducted to determine independent predictors of post-EVT infection and the associations between post-EVT infection and clinical outcomes.

RESULTS

A total of 675 patients were included in the analysis; 306 (45.3%) of them had post-EVT infections. Patients with post-EVT infection had a lower rate of functional independence than patients without infection (31% vs 65%, p = 0.006). In addition, patients with post-EVT infection achieved less early neurological improvement (ENI) after EVT (25.8% vs 47.4%, p < 0.001). For safety outcomes, the infection group had a higher incidence of any intracranial hemorrhage (23.9% vs 15.7%, p = 0.01) and symptomatic intracranial hemorrhage (10.1% vs 5.1%, p = 0.01). Unsuccessful recanalization (aOR 1.87, 95% CI 1.11-3.13; p = 0.02) and general anesthesia (aOR 2.22, 95% CI 1.25-3.95; p = 0.01) were identified as independent predictors for post-EVT infection in logistic regression analysis.

CONCLUSION

AIS patients who develop post-EVT infections are more likely to experience poor clinical outcomes. Unsuccessful recanalization and general anesthesia were independent risk factors for the development of post-EVT infection.

Patent Foramen Ovale Management for Secondary Stroke Prevention: State-of-the-Art Appraisal of Current Evidence

Patent foramen ovale (PFO) is frequently identified in young patients with ischemic stroke. Randomized controlled trials provide robust evidence supporting PFO closure in selected patients with cryptogenic ischemic stroke; however, several questions remain unanswered. This report summarizes current knowledge on the epidemiology of PFO-associated stroke, the role of PFO as a cause of stroke, and anatomic high-risk features. We also comment on breakthrough developments in patient selection algorithms for PFO closure in relation to the PFO-associated stroke causal likelihood risk stratification system. We further highlight areas for future research in PFO-associated stroke including the efficacy and safety of PFO closure in the elderly population, incidence, and long-term consequences of atrial fibrillation post-PFO closure, generalizability of the results of clinical trials in the real world, and the need for assessing the effect of neurocardiology teams on adherence to international recommendations. Other important knowledge gaps such as sex, race/ethnicity, and regional disparities in access to diagnostic technologies, PFO closure devices, and clinical outcomes in the real world are also discussed as priority research topics.