Should we use one-sided or two-sided P values in tests of significance?

Usability and Feasibility of the Antipsychotic Medication Decision Aid in a Community Program for First-Episode Psychosis

OBJECTIVE

Although antipsychotic medications are considered first-line treatment for psychosis, rates of discontinuation and nonadherence are high, and debate persists about their use. This pilot study aimed to explore the usability, feasibility, and potential impact of a shared decision making (SDM) intervention, the Antipsychotic Medication Decision Aid (APM-DA), for decisions about use of antipsychotic medications.

METHODS

A pilot randomized controlled trial was conducted with 17 participants in a first-episode psychosis program. Nine participants received the APM-DA, and eight received usual care.

RESULTS

After their appointments, intervention group participants had less decisional conflict and greater satisfaction with decisions than control group participants had. Use of the APM-DA did not increase appointment length. Comparison of the intervention outcomes with the control outcomes was limited because of the small sample.

CONCLUSIONS

The results support the feasibility and usability of an SDM process via the use of the APM-DA in routine community psychosis care.

Is it premature to formulate recommendations for policy and practice, based on culture and health research? A robust critique of the CultureForHealth (2022) report

Introduction

Arts and health practice and research has expanded rapidly since the turn of the millennium. A World Health Organization scoping review of a large body of evidence claims positive health benefits from arts participation and makes recommendations for policy and implementation of arts for health initiatives. A more recent scoping review (CultureForHealth) also claims that current evidence is sufficient to form recommendations for policy and practice. However, scoping reviews of arts and health research-without critical appraisal of included studies-do not provide a sound basis for recommendations on the wider implantation of healthcare interventions.

Methods

We performed a detailed assessment of 18 Randomised Controlled Trials (RCTs) on arts-based interventions included in Section 1 of the CultureForHealth report using the Joanna Briggs Institute Critical Appraisal Tool for RCTs (2023).

Results

The 18 RCTs included demonstrated considerable risks of bias regarding internal and statistical conclusion validity. Moreover, the trials are substantially heterogeneous with respect to settings, health-issues, interventions, and outcomes, which limits their external validity, reliability, and generalisability.

Conclusions

The absence of a critical appraisal of studies included in the CultureForHealth report leads to an overinterpretation and overstatement of the health outcomes of arts-based interventions. As such, the CultureForHealth review is not a suitable foundation for policy recommendations, nor for formulating guidance on implementation of arts-based interventions for health.

Psychometric Properties of Child Health Utility 9D (CHU9D) Proxy Version Administered to Parents and Caregivers of Children Aged 2-4 Years Compared with Pediatric Quality of Life Inventory™ (PedsQL)

OBJECTIVE

This study examines the psychometric properties of the Child Health Utility 9D (CHU9D) proxy version administered to parents/caregivers of 2-4-year-old Australian children compared with Pediatric Quality of Life Inventory™ version 4.0 (PedsQL).

METHODS

Data collected in 2021/2022 from parents/caregivers of 2-4-year-olds from the Australian pediatric multi-instrument comparison study were used. Feasibility, ceiling/floor effects, test-retest reliability, convergent validity, known-group validity, and responsiveness were assessed.

RESULTS

A total of 842 caregivers completed the survey at baseline, with 513 completing the follow-up survey. The CHU9D did not demonstrate ceiling effects in the sample with special health care needs, with only 6% of respondents reporting best levels for all nine dimensions. CHU9D correlated with PedsQL moderately-to-strongly between comparable items (correlation coefficients 0.34-0.70). CHU9D was able to differentiate between groups with known health differences with moderate-to-large effect sizes (Cohen's d 0.58-2.03). Moderate test-retest reliability was found for CHU9D in those reporting no health change at a 2-day follow-up (ICC 0.52). A standard response mean (SRM) of 0.25-0.44 was found for children with changes in general health and a SRM of 0.72-0.82 for children who reported worsened health when developing new illnesses, indicating small-to-large responsiveness according to different definitions of health changes. Compared with PedsQL, CHU9D had similar known-group validity and responsiveness and slightly poorer test-retest reliability.

CONCLUSION

The CHU9D was found to be valid and reliable to measure health-related quality-of-life in children aged 2-4 years, although with relatively low test-retest reliability in some dimensions. Further development and validation work is warranted.

Updated Surveillance Metrics and History of the COVID-19 Pandemic (2020-2023) in Latin America and the Caribbean: Longitudinal Trend Analysis

BACKGROUND

In May 2020, the World Health Organization (WHO) declared Latin America and the Caribbean (LAC) the epicenter of the COVID-19 pandemic, with over 40% of worldwide COVID-19-related deaths at the time. This high disease burden was a result of the unique circumstances in LAC.

OBJECTIVE

This study aimed to (1) measure whether the pandemic was expanding or contracting in LAC when the WHO declared the end of COVID-19 as a public health emergency of international concern on May 5, 2023; (2) use dynamic and genomic surveillance methods to describe the history of the pandemic in the region and situate the window of the WHO declaration within the broader history; and (3) provide, with a focus on prevention policies, a historical context for the course of the pandemic in the region.

METHODS

In addition to updates of traditional surveillance data and dynamic panel estimates from the original study, we used data on sequenced SARS-CoV-2 variants from the Global Initiative on Sharing All Influenza Data (GISAID) to identify the appearance and duration of variants of concern (VOCs). We used Nextclade nomenclature to collect clade designations from sequences and Pangolin nomenclature for lineage designations of SARS-CoV-2. Additionally, we conducted a 1-sided t test for whether the regional weekly speed (rate of novel COVID-19 transmission) was greater than an outbreak threshold of 10. We ran the test iteratively with 6 months of data across the period from August 2020 to May 2023.

RESULTS

The speed of pandemic spread for the region had remained below the outbreak threshold for 6 months by the time of the WHO declaration. Acceleration and jerk were also low and stable. Although the 1- and 7-day persistence coefficients remained statistically significant for the 120-day period ending on the week of May 5, 2023, the coefficients were relatively modest in magnitude (0.457 and 0.491, respectively). Furthermore, the shift parameters for either of the 2 most recent weeks around May 5, 2023, did not indicate any change in this clustering effect of cases on future cases. From December 2021 onward, Omicron was the predominant VOC in sequenced viral samples. The rolling t test of speed=10 became entirely insignificant from January 2023 onward.

CONCLUSIONS

Although COVID-19 continues to circulate in LAC, surveillance data suggest COVID-19 is endemic in the region and no longer reaches the threshold of the pandemic definition. However, the region experienced a high COVID-19 burden in the early stages of the pandemic, and prevention policies should be an immediate focus in future pandemics. Ahead of vaccination development, these policies can include widespread testing of individuals and an epidemiological task force with a contact-tracing system.

Nurses quality of life, sleep disturbance, and intention to leave critical care units: A cross-sectional moderated mediation analysis

OBJECTIVES

This study aims to explore the complex relationships between personal and demographic factors, intermediary factors such as quality of life (depression, anxiety, stress, burnout), and the mediating impact of sleep disturbance on nurses' intention to leave critical care units.

DESIGN

Cross-sectional quantitative survey.

SETTING

Data were collected from registered nurses at a major university hospital in southern Italy. Seven inpatient critical care units were sampled.

MAIN OUTCOME MEASURES

Intention to leave critical care units.

RESULTS

We included 160 participants recruited over five weeks in May and June 2023. The data showed that most were female, married, and possessed a bachelor's degree in nursing. The mean quality of life score was moderate, while stress, anxiety, and burnout were mild. A significant percentage of nurses reported poor sleep quality. Logistic regression indicates that service length did not significantly impact the intention to leave. The structural equation model showed that stress positively correlated with emotional exhaustion, whereas job quality was negatively associated with emotional exhaustion and the intention to leave. Sleep disturbance did not explain the relationship between stress and emotional fatigue; however, the results revealed that male gender moderated sleep mediation.

CONCLUSIONS

This study investigated factors influencing intention to leave among critical care unit nurses. The results suggest that the role of sleep disturbance should always be considered when assessing the issue. In this chain of causes, sleep disturbance explains the relationship between stress and emotional exhaustion. Furthermore, the strength of this mediation was influenced by gender, particularly by the male gender.

IMPLICATIONS FOR CLINICAL PRACTICE

Stress and emotional exhaustion significantly impact nurses' working quality of life, particularly when sleep quality is taken into account. This leads to a higher intention to leave critical care units. To reduce this tendency, healthcare managers could implement specific evidence-based interventions to promote a good climate of work, which would positively affect stress, emotional exhaustion and sleep disturbance. The likelihood of intention to leave decreased with achieving personal self-fulfilment among nurses.

The impact of a pharmacist-led cultural competence training on provider perceived preparedness and clinical care in patients with diabetes of Asian descent

BACKGROUND

Patients of Asian descent are under-represented in the U.S. health care system and provider cultural competence is inadequate in addressing Asian health disparities.

OBJECTIVES

The purpose of this study was to evaluate the impact of the pharmacist-led cultural competence training on provider self-perceived preparedness and diabetes-related health outcomes in patients of Asian descent.

METHODS

This study is a cross-sectional followed by a quasi-experimental design conducted in 2 phases in a primary care clinic. Phase one evaluated the association of providers' cross-cultural care survey (CCCS) scores with patients' diabetic health indices: hemoglobin A1c (HbA1C), systolic blood pressure (SBP), diastolic blood pressure, and body mass index. Phase 2 examined the impact of pharmacist-led cultural competence training on providers' cross-cultural competency using survey analysis as well as pre- and post-training diabetic health indices in patients of Asian descent.

RESULTS

Phase 1 CCCS results showed baseline cross-cultural competence of the providers is inadequate (N = 9 providers). Furthermore, a significant negative correlation was found between providers' CCCS score and patients' HbA1C (N = 49, P = 0.04). Phase 2 showed that cultural competence training significantly reduced providers' self-perceived "un-preparedness" to care for patients of alternative cultures (N = 30 providers). Average diabetic health indices for all patients (N = 95) before and after the training were not significantly different. In the subset of patients with uncontrolled diabetes (HbA1C ≥ 7), SBP and HbA1C were significantly reduced after the training (P = 0.032 and P = 0.039, respectively).

CONCLUSIONS

Pharmacist-led cultural competence training had a positive impact on provider self-assessment and diabetic clinical outcomes in uncontrolled patients.

Experience and Impact of COVID-19 on a Newly Formed Rural University Medical Office: Survey Study

BACKGROUND

The COVID-19 pandemic had large social effects, particularly in the fields of medicine and medical education. Medical organizations in the United States operate in overlapping contexts with interrelated goals inside multiple organizations, and the context of work strongly influenced how organizations were able to respond to COVID-19 restrictions.

OBJECTIVE

This research examines the experience and impact of COVID-19 on the implementation of a Health Resources and Services Administration grant in a newly formed university medical office with the interrelated goals of health policy, health outreach, and medical education. The goal is to understand how COVID-19 created different experiences and challenges for leaders and their collaborators working in medical education compared to those working in public health outreach or health policy.

METHODS

A survey about COVID-19 opportunities and challenges was administered to work unit leaders and their project collaborators. The most common experiences and challenges are shown, direct educational and other respondents' experiences and challenges are compared, and open-ended comment segments are analyzed.

RESULTS

Helping others adjust to digital work, remoteness, and coordination were common experiences during COVID-19. Common challenges include coordination and an inability to make comparisons to previous program years. On average, respondents had 11.3 (SD 7.8) experiences and 8.3 (SD 6.9) challenges considered in the survey. While all units were influenced by COVID-19 restrictions, medical education units had more experiences and challenges. Those involved directly in medical education experienced 69% (18.6/27) of their possible experiences and 54% (14.7/27) of their possible challenges on average compared to 35% (7/20) and 21% (4.2/20) among other respondents (P<.001). COVID-19 restrictions increased the complexity of project work and presented challenges, especially in terms of coordinating responses and access to locations.

CONCLUSIONS

The findings suggest that COVID-19 made the overall administration of programs more complex and drew attention from other medical and public health programs. While remoteness is appropriate for some medical education tasks, it is less appropriate for clinical learning. Remoteness presents an especially large challenge to clinical education. Employees now have expectations for remoteness to be built into programs and workplaces. Program administrators will have to integrate remoteness' benefits and drawbacks into their organization for the foreseeable future.

Sample size estimation in clinical trials using ventilator-free days as the primary outcome: a systematic review

BACKGROUND

Ventilator-free days (VFDs) are a composite endpoint increasingly used as the primary outcome in critical care trials. However, because of the skewed distribution and competitive risk between components, sample size estimation remains challenging. This systematic review was conducted to systematically assess whether the sample size was congruent, as calculated to evaluate VFDs in trials, with VFDs' distribution and the impact of alternative methods on sample size estimation.

METHODS

A systematic literature search was conducted within the PubMed and Embase databases for randomized clinical trials in adults with VFDs as the primary outcome until December 2021. We focused on peer-reviewed journals with 2021 impact factors greater than five. After reviewing definitions of VFDs, we extracted the sample size and methods used for its estimation. The data were collected by two independent investigators and recorded in a standardized, pilot-tested forms tool. Sample sizes were calculated using alternative statistical approaches, and risks of bias were assessed with the Cochrane risk-of-bias tool.

RESULTS

Of the 26 clinical trials included, 19 (73%) raised "some concerns" when assessing risks of bias. Twenty-four (92%) trials were two-arm superiority trials, and 23 (89%) were conducted at multiple sites. Almost all the trials (96%) were unable to consider the unique distribution of VFDs and death as a competitive risk. Moreover, significant heterogeneity was found in the definitions of VFDs, especially regarding varying start time and type of respiratory support. Methods for sample size estimation were also heterogeneous, and simple models, such as the Mann-Whitney-Wilcoxon rank-sum test, were used in 14 (54%) trials. Finally, the sample sizes calculated varied by a factor of 1.6 to 17.4.

CONCLUSIONS

A standardized definition and methodology for VFDs, including the use of a core outcome set, seems to be required. Indeed, this could facilitate the interpretation of findings in clinical trials, as well as their construction, especially the sample size estimation which is a trade-off between cost, ethics, and statistical power. Systematic review registration PROSPERO ID: CRD42021282304. Registered 15 December 2021 ( https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021282304 ).

Improving immunoassay detection accuracy of anti-SARS-CoV-2 antibodies through dual modality validation

A novel test strategy is proposed with dual-modality detection techniques for COVID-19 antibody detection. The full-length S protein of SARS-CoV-2 was chemically immobilized on a glass surface to capture anti-SARS-CoV-2 IgG in patient serum and was detected through either Electrochemical Impedance Spectroscopy (EIS) or fluorescence imaging with labeled secondary antibodies. Gold nanoparticles conjugated with protein G were used as the probe and the bound GNP-G was detected through EIS measurements. Anti-human-IgG conjugated with the fluorescent tag Alexa Fluor 488 was used as the probe for fluorescence imaging. Clinical SARS-CoV-2 IgG positive serum and negative controls were used to validate both modalities. For fluorescence-based detection, a high sensitivity was noticed with a quantification range of 0.01-0.1 A.U.C. and a LOD of 0.004 A.U.C. This study demonstrates the possibility of utilizing different measurement techniques in conjunction for improved COVID-19 serology testing.

Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) R47H Variant Causes Distinct Age- and Sex-Dependent Musculoskeletal Alterations in Mice

Previous studies proposed the Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), a receptor expressed in myeloid cells including microglia in brain and osteoclasts in bone, as a link between brain and bone disease. The TREM2 R47H variant is a known risk factor for Alzheimer's disease (AD), the most common form of dementia. To investigate whether altered TREM2 signaling could contribute to bone and skeletal muscle loss, independently of central nervous system defects, we used mice globally hemizygous for the TREM2 R47H variant (TREM2R47H/+ ), which do not exhibit AD pathology, and wild-type (WT) littermate control mice. Dxa/Piximus showed bone loss in female TREM2R47H/+ animals between 4 and 13 months of age and reduced cancellous and cortical bone (measured by micro-computed tomography [μCT]) at 13 months, which stalled out by 20 months of age. In addition, they exhibited decreased femoral biomechanical properties measured by three-point bending at 13 months of age, but not at 4 or 20 months. Male TREM2R47H/+ animals had decreased trabecular bone geometry but increased ultimate strain and failure force at 20 months of age versus WT. Only male TREM2R47H/+ osteoclasts differentiated more ex vivo after 7 days with receptor activator of nuclear factor κB ligand (RANKL)/macrophage colony-stimulating factor (M-CSF) compared to WT littermates. Yet, estrogen receptor alpha expression was higher in female and male TREM2R47H/+ osteoclasts compared to WT mice. However, female TREM2R47H/+ osteoclasts expressed less complement 3 (C3), an estrogen responsive element, and increased protein kinase B (Akt) activity, suggesting altered estrogen signaling in TREM2R47H/+ cells. Despite lower bone volume/strength in TREM2R47H/+ mice, skeletal muscle function measured by plantar flexion and muscle contractility was increased in 13-month-old female mutant mice. Overall, these data demonstrate that an AD-associated TREM2 variant can alter bone and skeletal muscle strength in a sex-dimorphic manner independent of central neuropathology, potentially mediated through changes in osteoclastic intracellular signaling. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The association between serum estradiol levels and sperm DNA integrity

In men from the general population, BMI has been associated with a lower sperm DNA fragmentation index (DFI). We wondered whether this could be due to estradiol, which is associated with BMI and reported important for sperm function. Our objective was to investigate the association between estradiol and DFI. In 2008-2010, we recruited 284 young men from the general population to deliver samples of semen and blood and answer questionnaires. Serum concentrations of reproductive hormones and DFI were analyzed, the latter using the Sperm Chromatin Structure Assay. Associations were studied using general linear models. The first model utilized metric values of estradiol, whereas the second model compared men with high and low levels, dichotomized by the median value. A possible interaction between estradiol and testosterone was also examined. When investigating metric estradiol levels and DFI, an inverse association was seen without adjustments (p = .02), but the statistical significance was lost at adjustments for potential confounders (p = .08). Men with lower estradiol levels (<88 pmol/L, mean 71 pmol/L) had a statistically significantly higher DFI than men with higher levels of estradiol (≥88 pmol/L, mean 110 pmol/L). Mean ratio difference was 1.21 (p = .002) without adjustments and 1.18 (p = .01) with adjustments. A statistically significant difference in DFI was observed in men with testosterone levels below median when comparing high and low estradiol (p < .001). This study supports the idea that serum estradiol levels are protective for sperm DNA integrity, at least at lower testosterone levels.

Impact of new-onset versus pre-existing atrial fibrillation on outcomes after transcatheter aortic valve replacement/implantation

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Atrial fibrillation increases the risk of all primary and secondary outcomes after TAVR/TAVI.

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NOAF is associated with a higher risk of 30-day mortality, stroke, and extended LOS after TAVR/TAVI.

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Pre-AF is associated with a higher risk of AKI and early bleeding episodes after TAVR/TAVI.

Patients with aortic stenosis who undergo transcatheter aortic valve replacement/transcatheter aortic valve implantation (TAVR/TAVI) experience a high incidence of pre-existing atrial fibrillation (pre-AF) and new-onset atrial fibrillation (NOAF) post-operatively. This systematic review and meta-analysis aimed to update current evidence concerning the incidence of 30-day mortality, stroke, acute kidney injury (AKI), length of stay (LOS), and early/late bleeding in patients with NOAF or pre-AF who undergo TAVR/TAVI. PubMed, Google Scholar, JSTOR, Cochrane Library, and Web of Science were searched for studies published between January 2012 and December 2020 reporting the association between NOAF/pre-AF and clinical complications after TAVR/TAVI. A total of 15 studies including 158,220 adult patients with TAVI/TAVR and NOAF or pre-AF were identified. Compared to patients in sinus rhythm, patients who developed NOAF had a higher risk of 30-day mortality, AKI, early bleeding events, extended LOS, and stroke after TAVR/TAVI (odds ratio [OR]: 3.18 [95% confidence interval [CI] 1.58, 6.40]) (OR: 3.83 [95% CI 1.18, 12.42]) (OR: 1.70 [95% CI 1.05, 2.74]) (OR: 13.96 [95% CI, 6.41, 30.40]) (OR: 2.51 [95% CI 1.59, 3.97], respectively). Compared to patients in sinus rhythm, patients with pre-AF had a higher risk of AKI and early bleeding episodes after TAVR/TAVI (OR: 2.43 [95% CI 1.10, 5.35]) (OR: 17.41 [95% CI 6.49, 46.68], respectively). Atrial fibrillation is associated with a higher risk of all primary and secondary outcomes. Specifically, NOAF but not pre-AF is associated with a higher risk of 30-day mortality, stroke, and extended LOS after TAVR/TAVI.

High-throughput mediation analysis of human proteome and metabolome identifies mediators of post-bariatric surgical diabetes control

To improve the power of mediation in high-throughput studies, here we introduce High-throughput mediation analysis (Hitman), which accounts for direction of mediation and applies empirical Bayesian linear modeling. We apply Hitman in a retrospective, exploratory analysis of the SLIMM-T2D clinical trial in which participants with type 2 diabetes were randomized to Roux-en-Y gastric bypass (RYGB) or nonsurgical diabetes/weight management, and fasting plasma proteome and metabolome were assayed up to 3 years. RYGB caused greater improvement in HbA1c, which was mediated by growth hormone receptor (GHR). GHR’s mediation is more significant than clinical mediators, including BMI. GHR decreases at 3 months postoperatively alongside increased insulin-like growth factor binding proteins IGFBP1/BP2; plasma GH increased at 1 year. Experimental validation indicates (1) hepatic GHR expression decreases in post-bariatric rats; (2) GHR knockdown in primary hepatocytes decreases gluconeogenic gene expression and glucose production. Thus, RYGB may induce resistance to diabetogenic effects of GH signaling.

Trial Registration: Clinicaltrials.gov NCT01073020.

Factors underlying the effects of gastric bypass surgery on glucose homeostasis are incompletely understood. Here the authors developed and applied high-throughput mediation analysis to identify proteome/metabolome mediators of improved glucose homeostasis after to gastric bypass surgery, and report that improved glycemia was mediated by the growth hormone receptor.

Sarcopenia in the elderly versus microcirculation, inflammation status, and oxidative stress: A cross-sectional study

BACKGROUND

Age-related mechanisms of sarcopenia associated with vascular function have been recently suggested. This study compared and tested associations between muscle mass and strength, microcirculation, inflammatory biomarkers, and oxidative stress in older adults classified as sarcopenic and non-sarcopenic.

METHODS

Thirty-three physically inactive individuals (72±7 yrs) were assigned to age-matched sarcopenic (SG) and non-sarcopenic (NSG) groups. Between-group comparisons were performed for appendicular skeletal mass (ASM), handgrip and isokinetic strength, microvascular function and morphology, C-reactive protein, insulin-like growth factor-1, tumor necrosis factor-alpha, interleukin-6 (IL-6), soluble vascular cell adhesion molecule-1, soluble intercellular adhesion molecule-1, endothelin-1, and oxidized low-density lipoprotein.

RESULTS

ASM and knee isokinetic strength were lower in SG than NSG (P <  0.05). No difference between groups was found for outcomes of microvascular function and morphology, but log-transformed IL-6 concentration was twice greater in SG vs. NSG (P = 0.02). Correlations between ASM index, handgrip and knee isokinetic strength vs. markers of microcirculatory function, capillary diameters, vascular reactivity, and endothelial injury were found only in SG.

CONCLUSION

Decreased ASM index and strength have been associated with microcirculatory profile, indicating that microcirculation impairment may be involved somehow in Sarcopenia development. The inflammation status, particularly elevated IL-6, seems to play an important role in this process.

Cultural differences in food detection

The ability to detect food plays an indispensable role in our survival and wellbeing. Previous psychological studies have revealed that food is detected more rapidly than non-food items. However, whether the detection of food could be modulated by cultural factors remains unknown. We investigated this issue in the present study using a visual search paradigm with Polish and Japanese participants. Photographs of international fast food, domestic Japanese food, or kitchen tools were presented alongside images of non-food distractors (cars). Participants were asked to judge whether the stimuli were all identical or not. The reaction time data showed that participants from both cultures detected food more rapidly than kitchen tools. Japanese participants detected fast food more rapidly than Japanese food, whereas Polish participants did not display such differences between food types. These results suggest that rapid detection of food is universal, but is modulated by cultural experiences.

Inducing Unconscious Stress

Abstract. Stress-related stimuli may be presented outside of awareness and may ultimately influence health by causing repetitive increases in physiological parameters, such as blood pressure (BP). In this study, we aimed to corroborate previous studies that demonstrated BP effects of subliminally presented stress-related stimuli. This would add evidence to the hypothesis that unconscious manifestations of stress can affect somatic health. Additionally, we suggest that these findings may be extended by measuring affective changes relating to these physiological changes, using measures for self-reported and implicit positive and negative affectivity. Using a repeated measures between-subject design, we presented either the prime word “angry” ( n = 26) or “relax” ( n = 28) subliminally (17 ms) for 100 trials to a student sample and measured systolic and diastolic BP, heart rate (HR), and affect. The “angry” prime, compared to the “relax” prime, did not affect any of the outcome variables. During the priming task, a higher level of implicit negative affect (INA) was associated with a lower systolic BP and diastolic BP. No association was found with HR. Self-reported affect and implicit positive affect were not related to the cardiovascular (CV) activity. In sum, anger and relax primes elicited similar CV activity patterns, but implicit measures of affect may provide a new method to examine the relationship between (unconscious) stress and health.

Effect of Doxycycline on Aneurysm Growth Among Patients With Small Infrarenal Abdominal Aortic Aneurysms: A Randomized Clinical Trial

IMPORTANCE

Abdominal aortic aneurysms affect more than 3% of US older adults.

OBJECTIVE

To test whether doxycycline reduces the growth of abdominal aortic aneurysm over 2 years as measured by maximum transverse diameter.

DESIGN, SETTING, AND PARTICIPANTS

Parallel, 2-group, randomized clinical trial that was conducted at 22 US clinical centers between May 2013 and January 2017, and enrolled patients 50 years or older with small (3.5-5.0 cm for men, 3.5-4.5 cm for women) infrarenal aneurysms. The final date of follow-up was July 31, 2018.

INTERVENTIONS

Patients were randomized to receive twice daily for 2 years doxycycline 100 mg orally (as capsules) (n = 133) or placebo (n = 128).

MAIN OUTCOMES AND MEASURES

The primary outcome was change in abdominal aortic aneurysm maximum transverse diameter measured from CT images at baseline and follow-up at 2 years. Patients were assigned ranks based on the maximum transverse diameter (measured or imputed) of the aorta and also if they underwent aneurysm repair or died. The ranks were converted to scores having a normal distribution to facilitate the primary analysis ("normal scores").

RESULTS

Of 261 patients randomized, no follow-up CT scans were obtained on 7 (3%), leaving a final analysis set of 129 patients assigned to doxycycline and 125 to placebo (mean [SD] age, 71.0 years [7.4 years], 35 women [14%]). The outcome normal scores used in the primary analysis were based on maximum transverse diameter (measured or imputed) in 113 patients (88%) in the doxycycline group and 112 patients (90%) in the placebo group; aneurysm repair in 13 (10%) and 9 (7%), and death in 3 (2%) and 4 (3%), respectively. The primary outcome, normal scores reflecting change in aortic diameter, did not differ significantly between the 2 groups, mean change in normal scores, 0.0262 vs -0.0258 (1-sided P = .71). Mean (SD) baseline maximum transverse diameter was 4.3 cm (0.4 cm) for doxycycline and 4.3 cm (0.4 cm) for placebo. At the 2-year follow-up, the change in measured maximum transverse diameter was 0.36 cm (95% CI, 0.31 to 0.40 cm) for 96 patients in the doxycycline group vs 0.36 cm (95% CI, 0.30 to 0.41 cm) for 101 patients in the placebo group (difference, 0.0; 95% CI, -0.07 to 0.07 cm; 2-sided P = .93). No patients were withdrawn from the study because of adverse effects. Joint pain occurred in 84 of 129 patients (65%) with doxycycline and 79 of 125 (63%) with placebo.

CONCLUSIONS AND RELEVANCE

Among patients with small infrarenal abdominal aortic aneurysms, doxycycline compared with placebo did not significantly reduce aneurysm growth at 2 years. These findings do not support the use of doxycycline for reducing the growth of small abdominal aortic aneurysms.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01756833.

Increased extracellular free-water in adult male rats following in utero exposure to maternal immune activation

BACKGROUND

In previous work, we applied novel in vivo imaging methods to reveal that white matter pathology in patients with first-episode psychosis (FEP) is mainly characterized by excessive extracellular free-water, and to a lesser extent by cellular processes, such as demyelination. Here, we apply a back-translational approach to evaluate whether or not a rodent model of maternal immune activation (MIA) induces patterns of white matter pathology that we observed in patients with FEP. To this end, we examined free-water and tissue-specific white matter alterations in rats born to mothers exposed to the viral mimic polyriboinosinic-polyribocytidylic acid (Poly-I:C) in pregnancy, which is widely used to produce alterations relevant to schizophrenia and is characterized by a robust neuroinflammatory response.

METHOD

Pregnant dams were injected on gestational day 15 with the viral mimic Poly-I:C (4 mg/kg) or saline. Diffusion-weighted magnetic resonance images were acquired from 17 male offspring (9 Poly-I:C and 8 saline) on postnatal day 90, after the emergence of brain structural and behavioral abnormalities. The free-water fraction (FW) and tissue-specific fractional anisotropy (FA_T), as well as conventional fractional anisotropy (FA) were computed across voxels traversing a white matter skeleton. Voxel-wise and whole-brain averaged white matter were tested for significant microstructural alterations in immune-challenged, relative to saline-exposed offspring.

RESULTS

Compared to saline-exposed offspring, those exposed to maternal Poly-I:C displayed increased extracellular FW averaged across voxels comprising a white matter skeleton (t(15) = 2.74; p = 0.01). Voxel-wise analysis ascribed these changes to white matter within the corpus callosum, external capsule and the striatum. In contrast, no significant between-group differences emerged for FA_T or for conventional FA, measured across average and voxel-wise white matter.

CONCLUSION

We identified excess FW across frontal white matter fibers of rats exposed to prenatal immune activation, analogous to our "bedside" observation in FEP patients. Findings from this initial experiment promote use of the MIA model to examine pathological pathways underlying FW alterations observed in patients with schizophrenia. Establishing these mechanisms has important implications for clinical studies, as free-water imaging reflects a feasible biomarker that has so far yielded consistent findings in the early stages of schizophrenia.

Interruptions, Unreasonable Tasks, and Quality-Threatening Time Pressure in Home Care: Linked to Attention Deficits and Slips, Trips, and Falls

BACKGROUND

In industrial countries, home care of community dwelling elderly people is rapidly growing. Frequent injuries in home caregivers result from slips, trips, and falls (STFs). The current study tests attentional cognitive failure to mediate the association between work stressors and STFs.

METHODS

A sample of 125 home caregivers participated in a questionnaire study and reported work interruptions, unreasonable tasks, quality-threatening time pressure, conscientiousness, attentional cognitive failures, and STFs.

RESULTS

In structural equation modeling, the mediation model was shown to fit empirical data. Indirect paths with attentional cognitive failures as the link between work stressors and STF were all significant in bootstrapping tests. An alternative accident-prone person model, that suggests individual differences in conscientiousness to predict attentional cognitive failures that predict more frequent work stressors and STFs, showed no significant paths between work conditions and STFs.

CONCLUSION

To prevent occupational injury, work should be redesigned to reduce work interruptions, unreasonable tasks, and quality-threatening time pressure in home care.

S-nitrosylation of NOS pathway mediators in the penis contributes to cavernous nerve injury-induced erectile dysfunction

cGMP-independent nitric oxide (NO) signaling occurs via S-nitrosylation. We evaluated whether aberrant S-nitrosylation operates in the penis under conditions of cavernous nerve injury and targets proteins involved in regulating erectile function. Adult male Sprague-Dawley rats underwent bilateral cavernous nerve crush injury (BCNI) or sham surgery. Rats were given a denitrosylation agent N-acetylcysteine (NAC, 300 mg/kg/day) or vehicle in drinking water starting 2 days before BCNI and continuing for 2 weeks following surgery. After assessment of erectile function (intracavernous pressure), penes were collected for measurements of S-nitrosylation by Saville-Griess and TMT-switch assays and PKG-I function by immunoblotting of phospho (P)-VASP-Ser-239. Erectile function was decreased (P<0.05) after BCNI, and it was preserved (P<0.05) by NAC treatment. Total S-nitrosothiols and total S-nitrosylated proteins were increased (P<0.05) after BCNI, and these were partially prevented by NAC treatment. S-nitrosylation of sGC was increased (P<0.05) after BCNI, and it was prevented (P<0.05) by NAC treatment. S-nitrosylation of eNOS was increased (P<0.05) after BCNI, and showed a trend towards decrease by NAC treatment. Protein expression of P-VASP-Ser-239 was decreased (P<0.05) after BCNI, and showed a trend towards increase by NAC treatment. In conclusion, erectile dysfunction following BCNI is mediated in part by S-nitrosylation of eNOS and its downstream signaling mediator GC, while denitrosylation protects erectile function by preserving the NO/cGMP signaling pathway.

Altered brain function in persistent postural perceptual dizziness: A study on resting state functional connectivity

This study used resting state functional magnetic resonance imaging (rsfMRI) to investigate whole brain networks in patients with persistent postural perceptual dizziness (PPPD). We compared rsfMRI data from 38 patients with PPPD and 38 healthy controls using whole brain and region of interest analyses. We examined correlations among connectivity and clinical variables and tested the ability of a machine learning algorithm to classify subjects using rsfMRI results. Patients with PPPD showed: (a) increased connectivity of subcallosal cortex with left superior lateral occipital cortex and left middle frontal gyrus, (b) decreased connectivity of left hippocampus with bilateral central opercular cortices, left posterior opercular cortex, right insular cortex and cerebellum, and (c) decreased connectivity between right nucleus accumbens and anterior left temporal fusiform cortex. After controlling for anxiety and depression as covariates, patients with PPPD still showed decreased connectivity between left hippocampus and right inferior frontal gyrus, bilateral temporal lobes, bilateral insular cortices, bilateral central opercular cortex, left parietal opercular cortex, bilateral occipital lobes and cerebellum (bilateral lobules VI and V, and left I-IV). Dizziness handicap, anxiety, and depression correlated with connectivity in clinically meaningful brain regions. The machine learning algorithm correctly classified patients and controls with a sensitivity of 78.4%, specificity of 76.9%, and area under the curve = 0.88 using 11 connectivity parameters. Patients with PPPD showed reduced connectivity among the areas involved in multisensory vestibular processing and spatial cognition, but increased connectivity in networks linking visual and emotional processing. Connectivity patterns may become an imaging biomarker of PPPD.

Behavioral and neuroanatomical outcomes in a rat model of preterm hypoxic-ischemic brain Injury: Effects of caffeine and hypothermia

The current study investigated behavioral and post mortem neuroanatomical outcomes in Wistar rats with a neonatal hypoxic-ischemic (HI) brain injury induced on postnatal day 6 (P6; Rice-Vannucci HI method; Rice et al., 1981). This preparation models brain injury seen in premature infants (gestational age (GA) 32-35 weeks) based on shared neurodevelopmental markers at time of insult, coupled with similar neuropathologic sequelae (Rice et al., 1981; Workman et al., 2013). Clinically, HI insult during this window is associated with poor outcomes that include attention deficit hyperactivity disorder (ADHD), motor coordination deficits, spatial memory deficits, and language/learning disabilities. To assess therapies that might offer translational potential for improved outcomes, we used a P6 HI rat model to measure the behavioral and neuroanatomical effects of two prospective preterm neuroprotective treatments - hypothermia and caffeine. Hypothermia (aka "cooling") is an approved and moderately efficacious intervention therapy for fullterm infants with perinatal hypoxic-ischemic (HI) injury, but is not currently approved for preterm use. Caffeine is a respiratory stimulant used during removal of infants from ventilation but has shown surprising long-term benefits, leading to consideration as a therapy for HI of prematurity. Current findings support caffeine as a preterm neuroprotectant; treatment significantly improved some behavioral outcomes in a P6 HI rat model and partially rescued neuropathology. Hypothermia treatment (involving core temperature reduction by 4 °C for 5 h), conversely, was found to be largely ineffective and even deleterious for some measures in both HI and sham rats. These results have important implications for therapeutic intervention in at-risk preterm populations, and promote caution in the application of hypothermia protocols to at-risk premature infants without further research.

Coronary artery calcium before and after hospitalization with pneumonia: The MESA study

Background

Epidemiological analyses demonstrate that pneumonia survivors have a higher risk of myocardial infarction than people with similar load of risk factors for atherosclerotic cardiovascular disease (ASCVD) but without pneumonia. This may be due to a higher baseline burden of ASCVD in patients with pneumonia that is not captured by the accounting of known ASCVD risk factors in epidemiological analyses or to unfavorable accelerating effects of pneumonia on atherosclerosis.

Methods

We analyzed data from the Multi-Ethnic Study of Atherosclerosis. We identified 54 participants that were hospitalized for pneumonia during study follow-up and that also had assessment of coronary artery calcium (CAC, an objective marker of coronary atherosclerotic burden) before and after this hospitalization. We matched them to 54 participants who were not hospitalized for pneumonia but that had CAC assessments at the same study visits as the pneumonia cases. We compared baseline CAC scores and their progression between groups.

Results

Baseline CAC scores were similar in both groups (median [IQR]; 6.3 [0–356.8] in pneumonia participants vs. 10.8 [0–178.3] in controls; p = 0.25). After a median of 4.8 years, the direction and magnitude of CAC score change, and the slope of CAC score progression between groups was also similar (median change [IQR], 21.8 [0 to 287.29] in participants with pneumonia versus 15.8 [0 to 140.94] in controls, p = 0.28; difference in slope, 7.7, 95% CI -9.0 to 24.6, p = 0.18). However, among participants with high baseline ASCVD risk (i.e. ACC/AHA 10-year risk estimate ≥7.5%), participants with pneumonia showed a larger increase in CAC scores (median change [IQR]; 159.10 [38.55–407.34] versus 48.72 [0.97–246.99] in controls; p = 0.02) and a trend towards a steeper slope of CAC score progression (difference in slope, 19.7, 95% CI -6.6 to 45.6, p = 0.07).

Conclusion

Pneumonia may accelerate the progression of atherosclerosis in people with high baseline ASCVD risk.

What are the odds of anxiety disorders running in families? A family study of anxiety disorders in mothers, fathers, and siblings of children with anxiety disorders

This family study investigated (1) the prevalence of anxiety disorders (ADs) in parents and siblings of children (n = 144) aged 8-18 years with ADs compared to control children (n = 49), and (2) the specificity of relationships between child-mother, child-father, and child-sibling ADs. Clinical interviews were used to assess current DSM-IV-TR ADs in children and siblings, and lifetime and current ADs in parents. Results showed that children with ADs were two to three times more likely to have at least one parent with current and lifetime ADs than the control children (odds ratio (OR) = 2.04 and 3.14). Children with ADs were more likely to have mothers with current ADs (OR = 2.51), fathers with lifetime ADs (OR = 2.84), but not siblings with ADs (OR = 0.75). Specific relationships between mother-child ADs were found for Social Anxiety Disorder (SAD, OR = 3.69) and Generalized Anxiety Disorder (OR = 3.47). Interestingly, all fathers and siblings with SAD came from families of children with SAD. Fathers of children with SAD were more likely to have lifetime ADs themselves (OR = 2.86). Findings indicate that children with ADs more often have parents with ADs, and specifically SAD is more prevalent in families of children with SAD. Influence of parent's (social) ADs should be considered when treating children with ADs.

On the use of one-sided statistical tests in biomedical research

There is a tendency to automatically use two-sided tests to assess the statistical significance of experimental results. Yet if a theory predicts the direction of an experimental outcome, or if for some practical (eg clinical) reason an outcome in that direction is the only one of interest, then it makes sense to use a one-sided test. The use of a two-sided test in these situations will lead to too many false negatives. Consequently treatment effects that corroborate a theory or that are of practical importance may be missed. This problem becomes particularly acute in the case of borderline results. Following a nonsignificant one-sided test, the possibility of an effect in the direction opposite to that predicted or required can be assessed in an exploratory fashion by computing the odds in favour of such an effect. Anyone is then at liberty to pursue this possibility as they see fit. The question of whether to use a one-sided or two-sided statistical test should always be decided on logical grounds not statistical ones, and suspicions regarding the motives of the investigator(s) should be disregarded. On the other hand, this choice can be avoided altogether by assuming that a treatment always has some effect (however small) and then computing the strength of the evidence in favour of the observed or predicted/required effect (ie 1-P, where P is the one-sided significance level of the test). With this approach one-sided and two-sided tests yield identical results, and so there is effectively only one type of test.

Does Digital Video Advertising Increase Population-Level Reach of Multimedia Campaigns? Evidence From the 2013 Tips From Former Smokers Campaign

Background

Federal and state public health agencies in the United States are increasingly using digital advertising and social media to promote messages from broader multimedia campaigns. However, little evidence exists on population-level campaign awareness and relative cost efficiencies of digital advertising in the context of a comprehensive public health education campaign.

Objective

Our objective was to compare the impact of increased doses of digital video and television advertising from the 2013 Tips From Former Smokers (Tips) campaign on overall campaign awareness at the population level. We also compared the relative cost efficiencies across these media platforms.

Methods

We used data from a large national online survey of approximately 15,000 US smokers conducted in 2013 immediately after the conclusion of the 2013 Tips campaign. These data were used to compare the effects of variation in media dose of digital video and television advertising on population-level awareness of the Tips campaign. We implemented higher doses of digital video among selected media markets and randomly selected other markets to receive similar higher doses of television ads. Multivariate logistic regressions estimated the odds of overall campaign awareness via digital or television format as a function of higher-dose media in each market area. All statistical tests used the .05 threshold for statistical significance and the .10 level for marginal nonsignificance. We used adjusted advertising costs for the additional doses of digital and television advertising to compare the cost efficiencies of digital and television advertising on the basis of costs per percentage point of population awareness generated.

Results

Higher-dose digital video advertising was associated with 94% increased odds of awareness of any ad online relative to standard-dose markets (P<.001). Higher-dose digital advertising was associated with a marginally nonsignificant increase (46%) in overall campaign awareness regardless of media format (P=.09). Higher-dose television advertising was associated with 81% increased odds of overall ad awareness regardless of media format (P<.001). Increased doses of television advertising were also associated with significantly higher odds of awareness of any ad on television (P<.001) and online (P=.04). The adjusted cost of each additional percentage point of population-level reach generated by higher doses of advertising was approximately US $440,000 for digital advertising and US $1 million for television advertising.

Conclusions

Television advertising generated relatively higher levels of overall campaign awareness. However, digital video was relatively more cost efficient for generating awareness. These results suggest that digital video may be used as a cost-efficient complement to traditional advertising modes (eg, television), but digital video should not replace television given the relatively smaller audience size of digital video viewers.

The Implicit Positive and Negative Affect Test: Validity and Relationship with Cardiovascular Stress-Responses

Self-report, i.e., explicit, measures of affect cannot fully explain the cardiovascular (CV) responses to stressors. Measuring affect beyond self-report, i.e., using implicit measures, could add to our understanding of stress-related CV activity. The Implicit Positive and Negative Affect Test (IPANAT) was administered in two studies to test its ecological validity and relation with CV responses and self-report measures of affect. In Study 1 students (N = 34) viewed four film clips inducing anger, happiness, fear, or no emotion, and completed the IPANAT and the Positive And Negative Affect Scale at baseline and after each clip. Implicit negative affect (INA) was higher and implicit positive affect (IPA) was lower after the anger inducing clip and vice versa after the happiness inducing clip. In Study 2 students performed a stressful math task with (n = 14) or without anger harassment (n = 15) and completed the IPANAT and a Visual Analog Scale as an explicit measure afterwards. Systolic (SBP), diastolic (DBP) blood pressure, heart rate (HR), heart rate variability (HRV), and total peripheral resistance (TPR) were recorded throughout. SBP and DBP were higher and TPR was lower in the harassment condition during the task with a prolonged effect on SBP and DBP during recovery. As expected, explicit negative affect (ENA) was higher and explicit positive affect (EPA) lower after harassment, but ENA and EPA were not related to CV activity. Although neither INA nor IPA differed between the tasks, during both tasks higher INA was related to higher SBP, lower HRV and lower TPR and to slower recovery of DBP after both tasks. Low IPA was related to slower recovery of SBP and DBP after the tasks. Implicit affect was not related to recovery of HR, HRV, and TPR. In conclusion, the IPANAT seems to respond to film clip-induced negative and positive affect and was related to CV activity during and after stressful tasks. These findings support the theory that implicitly measured affect can add to the explanation of prolonged stress-related CV responses that influence CV health.

Increasing the dose of television advertising in a national antismoking media campaign: results from a randomised field trial

Background

While antismoking media campaigns have demonstrated effectiveness, less is known about the country-level effects of increased media dosing. The 2012 US Tips From Former Smokers (Tips) campaign generated approximately 1.6 million quit attempts overall; however, the specific dose–response from the campaign was only assessed by self-report.

Objective

Assess the impact of higher ad exposure during the 2013 Tips campaign on quit-related behaviours and intentions, campaign awareness, communication about campaign, and disease knowledge.

Methods

A 3-month national media buy was supplemented within 67 (of 190) randomly selected local media markets. Higher-dose markets received media buys 3 times that of standard-dose markets. We compared outcomes of interest using data collected via web-based surveys from nationally representative, address-based probability samples of 5733 cigarette smokers and 2843 non-smokers.

Results

In higher-dose markets, 87.2% of smokers and 83.9% of non-smokers recalled television campaign exposure versus 75.0% of smokers and 73.9% of non-smokers in standard-dose markets. Among smokers overall, the relative quit attempt rate was 11% higher in higher-dose markets (38.8% vs 34.9%; p<0.04). The higher-dose increase was larger in African-Americans (50.9% vs 31.8%; p<0.01). Smokers in higher-dose markets without a mental health condition, with a chronic health condition, or with only some college education made quit attempts at a higher rate than those in standard-dose markets. Non-smokers in higher-dose markets were more likely to talk with family or friends about smoking dangers (43.1% vs 35.7%; p<0.01) and had greater knowledge of smoking-related diseases.

Conclusions

The US 2013 Tips antismoking media campaign compared standard and higher doses by randomisation of local media markets. Results demonstrate the effectiveness of a higher dose for engaging non-smokers and further increasing quit attempts among smokers, especially African-Americans.

An RCT to Treat Learning Impairment in Traumatic Brain Injury

Objective. To examine the efficacy of the modified Story Memory Technique (mSMT) to improve learning (ie, acquisition) and memory in participants with TBI. The mSMT is a behavioral intervention that teaches context and imagery to facilitate learning within 10 sessions over 5 weeks. Methods. A total of 69 participants with moderate-severe Traumatic Brain Injury (TBI), 35 in the treatment group and 34 in the placebo control group, completed this double-blind, placebo-controlled randomized clinical trial. A baseline neuropsychological assessment was administered, including questionnaires assessing everyday memory. Repeat assessments were conducted immediately posttreatment and 6 months following treatment. Participants in the treatment group were randomly assigned to a booster session or a non–booster session group after completion of treatment with the mSMT to examine the efficacy of monthly booster sessions in facilitating the treatment effect over time. Results. The treatment group demonstrated significant improvement on a prose memory task relative to the placebo group posttreatment (η2 = 0.064 medium effect). Similar results were noted on objective measures of everyday memory, specifically prospective memory (Cohen’s w = 0.43, medium effect), and family report of disinhibition in daily life (η2 = 0.046, medium effect). Conclusion. The mSMT is effective for improving learning and memory in TBI. Classification of evidence. Based on widely accepted classification systems for treatment study design, this study provides class I evidence that the mSMT behavioral intervention improves both objective memory and everyday memory in persons with TBI over 5 weeks. Thus, this study extends the evidence for efficacy of the treatment protocol to a sample of persons with TBI.

Fisher, Neyman-Pearson or NHST? A tutorial for teaching data testing

Despite frequent calls for the overhaul of null hypothesis significance testing (NHST), this controversial procedure remains ubiquitous in behavioral, social and biomedical teaching and research. Little change seems possible once the procedure becomes well ingrained in the minds and current practice of researchers; thus, the optimal opportunity for such change is at the time the procedure is taught, be this at undergraduate or at postgraduate levels. This paper presents a tutorial for the teaching of data testing procedures, often referred to as hypothesis testing theories. The first procedure introduced is Fisher's approach to data testing—tests of significance; the second is Neyman-Pearson's approach—tests of acceptance; the final procedure is the incongruent combination of the previous two theories into the current approach—NSHT. For those researchers sticking with the latter, two compromise solutions on how to improve NHST conclude the tutorial.

Mechanisms of Unexplained Neurological Deterioration After Intravenous Thrombolysis

Background and Purpose—

Unstable clinical course characterizes the first 24 hours after thrombolysis for anterior circulation stroke, including early neurological deterioration (END), a secondary complication consistently predictive of poor outcome. Apart from straightforward causes, such as intracerebral hemorrhage and malignant edema, the mechanism of END remains unclear in the majority of cases (END unexplained ). Based on the core/penumbra model, we tested the hypothesis that END unexplained is caused by infarct growth beyond the initial penumbra and assessed the associated vascular patterns.

Methods—

From our database of consecutive thrombolyzed patients (n=309), we identified 10 END unexplained cases who had undergone both admission and 24-hour MRI. Diffusion-weighted imaging lesion growth both within and beyond the acute penumbra (T max >6 seconds) was mapped voxelwise. These 10 cases were compared with 30 no-END controls extracted from the database blinded to 24-hour diffusion-weighted imaging to individually match cases (3/case) according to 4 previously identified clinical and imaging variables.

Results—

As predicted, lesion growth beyond initial penumbra was present in 9 of 10 END unexplained patients (substantial in 8) and its volume was significantly larger in cases than controls (2 P =0.047). All END unexplained cases had proximal arterial occlusion initially, of which only 2 had recanalized at 24 hours.

Conclusions—

In this exploratory study, most instances of END unexplained were related to diffusion-weighted imaging growth beyond acute penumbra. Consistent presence of proximal occlusion at admission and lack of recanalization at 24 hours in most cases suggest that hemodynamic factors played a key role, via for instance systemic instability/collateral failure or secondary thromboembolic processes. Preventing END after tissue-type plasminogen activator using, eg, early antithrombotics may therefore be feasible.