Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of a Prospective, Multicenter, Controlled Trial of Mobile Stroke Units

OBJECTIVE

This study was undertaken to examine averted stroke in optimized stroke systems.

METHODS

This secondary analysis of a multicenter trial from 2014 to 2020 compared patients treated by mobile stroke unit (MSU) versus standard management. The analytical cohort consisted of participants with suspected stroke treated with intravenous thrombolysis. The main outcome was a tissue-defined averted stroke, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis and no acute infarction/hemorrhage on imaging. An additional outcome was stroke with early symptom resolution, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis.

RESULTS

Among 1,009 patients with a median last known well to thrombolysis time of 87 minutes, 159 (16%) had tissue-defined averted stroke and 276 (27%) had stroke with early symptom resolution. Compared with standard management, MSU care was associated with more tissue-defined averted stroke (18% vs 11%, adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.13-2.98) and stroke with early symptom resolution (31% vs 21%, aOR = 1.74, 95% CI = 1.12-2.61). The relationships between thrombolysis treatment time and averted/early recovered stroke appeared nonlinear. Most models indicated increased odds for stroke with early symptom resolution but not tissue-defined averted stroke with earlier treatment. Additionally, younger age, female gender, hyperlipidemia, lower National Institutes of Health Stroke Scale, lower blood pressure, and no large vessel occlusion were associated with both tissue-defined averted stroke and stroke with early symptom resolution.

INTERPRETATION

In optimized stroke systems, 1 in 4 patients treated with thrombolysis recovered within 24 hours and 1 in 6 had no demonstrable brain injury on imaging. ANN NEUROL 2024;95:347-361.

Outcomes of patients with pre-existing disability managed by mobile stroke units: A sub-analysis of the BEST-MSU study

BACKGROUND

Few data exist on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials. A recent trial of mobile stroke units (MSUs) demonstrated faster treatment and improved outcomes, and included PD patients.

AIM

To determine outcomes with tissue plasminogen activator (tPA), and benefit of MSU versus management by emergency medical services (EMS), for PD patients.

METHODS

Primary outcomes were utility-weighted modified Rankin Scale (uw-mRS). Linear and logistic regression models compared outcomes in patients with versus without PD, and PD patients treated by MSU versus standard management by EMS. Time metrics, safety, quality of life, and health-care utilization were compared.

RESULTS

Of the 1047 tPA-eligible ischemic stroke patients, 254 were with PD (baseline mRS 2-5) and 793 were without PD (baseline mRS 0-1). Although PD patients had worse 90-day uw-mRS, higher mortality, more health-care utilization, and worse quality of life than non-disabled patients, 53% returned to at least their baseline mRS, those treated faster had better outcome, and there was no increased bleeding risk. Comparing PD patients treated by MSU versus EMS, 90-day uw-mRS was 0.42 versus 0.36 (p = 0.07) and 57% versus 46% returned to at least their baseline mRS. There was no interaction between disability status and MSU versus EMS group assignment (p = 0.67) for 90-day uw-mRS.

CONCLUSION

PD did not prevent the benefit of faster treatment with tPA in the BEST-MSU study. Our data support inclusion of PD patients in the MSU management paradigm.

Long-term immune response to SARS-CoV-2 infection and vaccination in children and adolescents

BACKGROUND

This analysis examined the durability of antibodies present after SARS-CoV-2 infection and vaccination in children and adolescents.

METHODS

Data were collected over 4 time points between October 2020-November 2022 as part of a prospective population-based cohort aged 5-to-19 years (N = 810). Results of the (1) Roche Elecsys® Anti-SARS-CoV-2 Immunoassay for detection of antibodies to the SARS-CoV-2 nucleocapsid protein (Roche N-test); and (2) qualitative and semi-quantitative detection of antibodies to the SARS CoV-2 spike protein receptor binding domain (Roche S-test); and (3) self-reported antigen/PCR COVID-19 test results, vaccination and symptom status were analyzed.

RESULTS

N antibody levels reached a median of 84.10 U/ml (IQR: 20.2, 157.7) cutoff index (COI) ~ 6 months post-infection and increased slightly to a median of 85.25 (IQR: 28.0, 143.0) COI at 12 months post-infection. Peak S antibody levels were reached at a median of 2500 U/mL ~6 months post-vaccination and remained for ~12 months (mean 11.6 months, SD 1.20).

CONCLUSIONS

This analysis provides evidence of robust durability of nucleocapsid and spike antibodies in a large pediatric sample up to 12 months post-infection/vaccination. This information can inform pediatric SARS-CoV-2 vaccination schedules.

IMPACT

This study provided evidence of robust durability of both nucleocapsid and spike antibodies in a large pediatric sample up to 12 months after infection. Little is known about the long-term durability of natural and vaccine-induced SARS-CoV-2 antibodies in the pediatric population. Here, we determined the durability of anti-SARS-CoV-2 spike (S-test) and nucleocapsid protein (N-test) in children/adolescents after SARS-CoV-2 infection and/or vaccination lasts at least up to 12 months. This information can inform future SARS-CoV-2 vaccination schedules in this age group.

SARS-CoV-2 Serostatus and COVID-19 Illness Characteristics by Variant Time Period in Non-Hospitalized Children and Adolescents

OBJECTIVE

To describe COVID-19 illness characteristics, risk factors, and SARS-CoV-2 serostatus by variant time period in a large community-based pediatric sample.

DESIGN

Data were collected prospectively over four timepoints between October 2020 and November 2022 from a population-based cohort ages 5 to 19 years old.

SETTING

State of Texas, USA.

PARTICIPANTS

Participants ages 5 to 19 years were recruited from large pediatric healthcare systems, Federally Qualified Healthcare Centers, urban and rural clinical practices, health insurance providers, and a social media campaign.

EXPOSURE

SARS-CoV-2 infection.

MAIN OUTCOME(S) AND MEASURE(S)

SARS-CoV-2 antibody status was assessed by the Roche Elecsys^® Anti-SARS-CoV-2 Immunoassay for detection of antibodies to the SARS-CoV-2 nucleocapsid protein (Roche N-test). Self-reported antigen or PCR COVID-19 test results and symptom status were also collected.

RESULTS

Over half (57.2%) of the sample (N = 3911) was antibody positive. Symptomatic infection increased over time from 47.09% during the pre-Delta variant time period, to 76.95% during Delta, to 84.73% during Omicron, and to 94.79% during the Omicron BA.2. Those who were not vaccinated were more likely (OR 1.71, 95% CI 1.47, 2.00) to be infected versus those fully vaccinated.

CONCLUSIONS

Results show an increase in symptomatic COVID-19 infection among non-hospitalized children with each progressive variant over the past two years. Findings here support the public health guidance that eligible children should remain up to date with COVID-19 vaccinations.

Abstract WP6: Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of the BEST-MSU Trial

Introduction: While the goal of IV tissue plasminogen activator (TPA) is to prevent infarction, few data exist on averted stroke.

Methods: Secondary analysis of a multicenter trial from 2014-2020 comparing outcomes between patients treated for stroke by mobile stroke unit (MSU) vs standard care (SC). The analytical cohort were patients with suspected stroke treated with IV TPA. The primary outcome was a time-defined averted stroke diagnosis, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours. The secondary outcome was a tissue-defined averted stroke diagnosis, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours and no acute infarction/hemorrhage on imaging. We used multivariable logistic regression to evaluate associations between study exposures (demographics, comorbidities, stroke characteristics) and outcomes.

Results: Among 1009 patients with a median last known well-to-TPA time of 87 minutes, 276 patients (27%) had a time-defined averted stroke (31% MSU, 21% SC) and 159 patients (16%) had a tissue-defined averted stroke (18% MSU, 11% SC). Factors independently associated with time-defined averted stroke were younger age (OR, 0.98; 95% CI, 0.96-0.99), female sex (0R, 0.51; 95% CI, 0.36-0.74), hyperlipidemia (OR, 1.81, 95% CI, 1.24-2.64), normal premorbid function (0R, 2.22; 95% CI, 1.37-3.67), lower glucose (OR, 0.996; 95% CI, 0.993-0.999), lower MAP (OR, 0.991; 95% CI, 0.983-0.998), MSU care (OR, 1.77; 95% CI, 1.21-2.62), lower NIH stroke scale (OR, 0.89; 95% CI, 0.86-0.93), and no large vessel occlusion (LVO) (OR, 0.52; 95% CI, 0.32-0.83). For tissue-based averted stroke, younger age, female sex, hyperlipidemia, lower MAP, MSU treatment, lower NIH stroke scale, and no LVO were significantly associated.

Conclusion: In a modern acute stroke trial, one-in-four patients treated with TPA for stroke recovered within 24 hours and one-in-six had no demonstrable brain injury on imaging. Younger age, female sex, hyperlipidemia, lower MAP, MSU care, lower stroke severity, and no LVO may increase the odds of averting stroke.

Abstract WMP2: Acute Stroke Treatment In Patients With Pre-exiting Disability: A Secondary Analysis Of The BEST-MSU Trial

Background: Few data exists on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials.

Methods: A pre-specified subgroup analysis of tPA-eligible patients with PD enrolled in a prospective multicenter trial of Mobile Stroke Units (MSUs) vs standard management by emergency medical services (EMS). All patients had baseline mRS scores. Co-primary outcomes were mean utility-weighted modified Rankin Scale score (uw-mRS) and return to baseline mRS at 90 days. Linear and logistic regression models compared outcomes in patients with vs without PD, and patients with PD treated by MSU vs EMS. Time metrics, safety, quality of life, and health-care utilization were also compared.

Results: Of 1047 patients, 254 had baseline mRS >= 2 (159 MSU, 95 EMS; 31% mRS 2, 52% mRS 3, 17% mRS 4). Compared to patients without disability, patients with PD were older, had higher NIHSS, more comorbidities, less often lived at home, were treated slower, and had less thrombectomy. Patients with PD had worse 90-day uw-mRS (0.39 vs 0.80), higher mortality, more health-care utilization and worse quality of life than patients without PD. However, rates of symptomatic intracranial hemorrhage and final diagnoses of stroke mimics were similar between groups, and 52% of patients with PD returned to their baseline mRS. Patients with PD treated within the first hour had better 90-day uw-mRS than those treated later (0.48 vs 0.36, p=0.01). Comparing patients with PD treated by MSU vs EMS, time from last-known-well to tPA bolus was shorter (82 vs 111 min), and 24% vs 0% were treated in the first hour. Among patients with PD, MSU patients had non-significantly better 90-day uw-mRS (0.41 vs 0.35, p=0.09) and higher rate of returning to baseline mRS (56% vs 44%, p=0.09) than EMS patients. There was no interaction between either time to treatment (p=0.24) or MSU vs EMS group assignment (p= 0.42), 90-day uw-mRS, and PD vs no disability status.

Conclusion: Although outcomes after stroke are less favorable in patients with vs without PD, in a large, controlled trial, we found no interaction between baseline disability and the benefit of MSU treatment. Our data support the earliest treatment of acute stroke patients regardless of premorbid functional status.

Antibody Duration After Infection From SARS-CoV-2 in the Texas Coronavirus Antibody Response Survey

Understanding the duration of antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that causes COVID-19 is important to controlling the current pandemic. Participants from the Texas Coronavirus Antibody Response Survey (Texas CARES) with at least 1 nucleocapsid protein antibody test were selected for a longitudinal analysis of antibody duration. A linear mixed model was fit to data from participants (n = 4553) with 1 to 3 antibody tests over 11 months (1 October 2020 to 16 September 2021), and models fit showed that expected antibody response after COVID-19 infection robustly increases for 100 days postinfection, and predicts individuals may remain antibody positive from natural infection beyond 500 days depending on age, body mass index, smoking or vaping use, and disease severity (hospitalized or not; symptomatic or not).

Strategies to Estimate Prevalence of SARS-CoV-2 Antibodies in a Texas Vulnerable Population: Results From Phase I of the Texas Coronavirus Antibody Response Survey

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and immunity remains uncertain in populations. The state of Texas ranks 2nd in infection with over 2.71 million cases and has seen a disproportionate rate of death across the state. The Texas CARES project was funded by the state of Texas to estimate the prevalence of SARS-CoV-2 antibody status in children and adults. Identifying strategies to understand natural as well as vaccine induced antibody response to COVID-19 is critical.

Materials and Methods: The Texas CARES (Texas Coronavirus Antibody Response Survey) is an ongoing prospective population-based convenience sample from the Texas general population that commenced in October 2020. Volunteer participants are recruited across the state to participate in a 3-time point data collection Texas CARES to assess antibody response over time. We use the Roche Elecsys® Anti-SARS-CoV-2 Immunoassay to determine SARS-CoV-2 antibody status.

Results: The crude antibody positivity prevalence in Phase I was 26.1% (80/307). The fully adjusted seroprevalence of the sample was 31.5%. Specifically, 41.1% of males and 21.9% of females were seropositive. For age categories, 33.5% of those 18–34; 24.4% of those 35–44; 33.2% of those 45–54; and 32.8% of those 55+ were seropositive. In this sample, 42.2% (89/211) of those negative for the antibody test reported having had a COVID-19 test.

Conclusions: In this survey we enrolled and analyzed data for 307 participants, demonstrating a high survey and antibody test completion rate, and ability to implement a questionnaire and SARS-CoV-2 antibody testing within clinical settings. We were also able to determine our capability to estimate the cross-sectional seroprevalence within Texas's federally qualified community centers (FQHCs). The crude positivity prevalence for SARS-CoV-2 antibodies in this sample was 26.1% indicating potentially high exposure to COVID-19 for clinic employees and patients. Data will also allow us to understand sex, age and chronic illness variation in seroprevalence by natural and vaccine induced. These methods are being used to guide the completion of a large longitudinal survey in the state of Texas with implications for practice and population health.

Benefits of stroke treatment delivered using a mobile stroke unit trial

Rationale

Mobile stroke units speed treatment for acute ischemic stroke, thereby possibly improving outcomes.

Aim

To compare mobile stroke unit and standard management clinical outcomes, healthcare utilization, and cost-effectiveness in tissue plasminogen activator-eligible acute ischemic stroke patients calling 911.

Sample size

693. Eighty percent power with 0.05 type I error rate to detect a difference of 0.09 in mean utility-weighted modified Rankin scale between groups.

Design

Phase III, multicenter, prospective cluster-randomized (mobile stroke unit versus standard management weeks) comparative effectiveness study in tissue plasminogen activator-eligible patients.

Outcomes

Primary: Ninety-day mean utility-weighted modified Rankin scale. Coprimary: cost-effectiveness based on EQ5D quality of life and one year poststroke costs.

Analysis

Two-sample t-test and linear regression adjusting for covariates; incremental cost-effectiveness ratio and net benefit regression.

Results

As of March 2017, 288 tissue plasminogen activator-eligible patients have been enrolled (173 in the mobile stroke unit arm and 115 in the standard management arm). Two new centers start in early 2017 with target end of recruitment September 2019.

Conclusion

This is the first randomized study to test for disability, healthcare utilization, and cost-effectiveness of a mobile stroke unit. The progress of the study suggests that it is feasible. Management of tissue plasminogen activator eligible acute ischemic stroke patients by a mobile stroke unit could potentially result in less disability and healthcare utilization, and be cost effective. Mobile stroke units are very costly. This trial may determine if the fixed cost can be justified by a reduction in disability and healthcare utilization.

Clinical Trial Registration

NCT02190500.

Carcinoma in diverticulum of female urethra

A case of carcinoma originating in a diverticulum of the urethra in a female patient is presented. A review of 143 cases of carcinoma of the female urethra treated from 1948 to 1984 at The University of Texas M. D. Anderson Hospital and Tumor Institute at Houston disclosed 6 additional patients with diverticular carcinoma. Analysis of their clinical features, treatments--various combinations of primary excision, radiotherapy, and chemotherapy--and survival results indicate that survival is primarily a function of grade. Only 40 cases of carcinoma in urethral diverticula are recorded in the world literature. The majority are adenocarcinomas, and the most frequent presenting symptoms are dysuria, frequency, and urgency. Radiotherapy successfully established long-term control of the disease with low morbidity in all of our patients who had low-grade tumors.