Linear Mixed-effects Analysis Research Articles

Individualised monitoring programme for pulmonary rehabilitation of patients with chronic obstructive pulmonary disease-study protocol for a randomised controlled trial.

Chronic obstructive pulmonary disease (COPD) is characterised mainly by exertional dyspnoea, which may lead to activity reduction. Pulmonary rehabilitation (PR) is considered capable of mitigating these impairments. However, access to PR is limited to specialised centres, especially during the coronavirus disease 2019 pandemic. Moreover, low-cost home rehabilitation programmes have non-individualised prescriptions, which might lead to inconsistent clinical effects in patients with COPD. Therefore, it is important to develop new, low-cost protocols involving individualised prescriptions and staff supervision. This is a descriptive protocol for a randomised controlled study at the Grade III A Hospital in Tianjin. The sample size was calculated according to a described formula. Fifty-six participants will be selected and randomly allocated into two groups: (I) control (traditional PR training, medication, and nursing interventions); and (II) intervention [PR training in the hospital and at home by the Cardiopulmonary Rehabilitation System Management Platform (CSM)]. The protocol will be performed twice a week for 8 consecutive weeks in the outpatient clinic, and the training will be performed by the application of the CSM system in the final 6 months of the trial. The study will assess lung function and physical fitness and analyse the scores of the modified Medical Research Council Dyspnoea Scale, the COPD assessment test, the International Classification of Functioning, Disability, and Health, and the 6-minute walk test before and after the training protocol. Comparison of differences will be performed using repeated measures analysis of variance, a linear mixed effects analysis, or a non-parametric test, which will include only participants who completed all outcome measures and followed the intervention protocol. The study results will be disseminated through presentations at scientific conferences and publications in peer-reviewed journals. The new, low-cost supervised rehabilitation programmes are expected to present positive results, making PR programmes more accessible and effective for patients with COPD. The study was registered in the Chinese Clinical Trial Registry: ChiCTR2000040723.

Apathy, cognition and beta amyloid in African Americans in the AA‐FAIM cohort

AbstractBackgroundThe prodrome of cognitive declines and/or dementia may include late‐life neuropsychiatric symptoms such as apathy. In primarily non‐Hispanic White samples, apathy associates with both cognition and amyloid deposition in cognitively intact patients and those with Alzheimer’s disease (AD). However, little is known about these relationships in African Americans, who are both disproportionately affected by AD and under‐represented in AD research. Apathy could reflect higher levels of proteinopathy or occur co‐morbidly, exacerbating its deleterious effects. We examined associations between apathy and cognition and their potential moderation by plasma beta amyloid in cognitively healthy African American participants.MethodStudy participants enrolled in African Americans Fighting Alzheimer’s In Mid‐Life(AA‐FAIM, a linked study to the WRAP and Wisconsin ADRC) were included in the analytic sample (N = 166; Table 1) if they had ≥1 cognitive visits, plasma amyloid biomarker data, and apathy ratings by study partners using the Neuropsychiatric Inventory Questionnaire (NPI‐Q) or the Apathy Evaluation Scale (AES). Cognitive outcomes included performance on measures of processing speed, mental flexibility and immediate and delayed memory. We used linear mixed models to examine association of baseline apathy with cognitive performance measures at multiple time points, and the moderation of apathy‐cognition relationships by plasma Aβ42/40 ratio (C2N, USA). Apathy‐cognitive outcome pairings were selected based on significant findings from a proof‐of‐concept linear mixed effects analysis of the full Wisconsin ADRC sample.ResultResults are shown in Table 2. Among AA‐FAIM participants, NPI‐Q apathy was associated with RAVLT immediate (estimate = ‐7.7, p = .001) and delayed recall (estimate = ‐3.2, p = .001). However, AES was unrelated to Trails A or B performance. There were no associations between plasma amyloid or the Aβ42/40*apathy interaction term with any cognitive outcomes.ConclusionPartner‐rated apathy, but not plasma Aβ42/40, was related to cognition in our African American participants, an important finding given limited data available on this population. It will be critical to address apathy and its antecedents to improve the cognitive and affective health of African American older adults. Future research needs to expand cohorts to African American and other diverse populations to investigate disease mechanisms in Alzheimer’s disease and related dementias more inclusively.

Quantifying refractive error in companion dogs with and without nuclear sclerosis: 229 eyes from 118 dogs.

To evaluate the relationship between nuclear sclerosis (NS) and refractive error in companion dogs. One hundred and eighteen companion dogs. Dogs were examined and found to be free of significant ocular abnormalities aside from NS. NS was graded from 0 (absent) to 3 (severe) using a scale developed by the investigators. Manual refraction was performed. The effect of NS grade on refractive error was measured using a linear mixed effects analysis adjusted for age. The proportion of eyes with >1.5 D myopia in each NS grade was evaluated using a chi-square test. Visual impairment score (VIS) was obtained for a subset of dogs and compared against age, refractive error, and NS grade. Age was strongly correlated with NS grade (p < .0001). Age-adjusted analysis of NS grade relative to refraction showed a mild but not statistically significant increase in myopia with increasing NS grade, with eyes with grade 3 NS averaging 0.58-0.88 D greater myopia than eyes without NS. However, the myopia of >1.5 D was documented in 4/58 (6.9%) eyes with grade 0 NS, 12/91 (13.2%) eyes with grade 1 NS, 13/57 (22.8%) eyes with grade 2 NS, and 7/23 (30.4%) eyes with grade 3 NS. Risk of myopia >1.5 D was significantly associated with increasing NS grade (p = .02). VIS was associated weakly with refractive error, moderately with age, and significantly with NS grade. NS is associated with visual deficits in some dogs but is only weakly associated with myopia. More work is needed to characterize vision in aging dogs.

Effects of Age, Sex, and Postconcussive Symptoms on Domain-Specific Quality of Life a Year After Mild Traumatic Brain Injury.

To identify the factors influencing longitudinal changes in patients' scores across 6 domains of the Quality of Life after Brain Injury (QOLIBRI) instrument 1 year after mild traumatic brain injury (mTBI). This was a longitudinal cohort study. Eligible patients with a new diagnosis of mTBI were recruited from the outpatient clinics of the neurosurgery departments of 3 teaching hospitals in Taipei City, Taiwan. In total, 672 patients participated in the baseline assessment. Postinjury follow-up was conducted at 6 and 12 months. Six domains of the 37-item QOLIBRI: Cognition, Self, Daily Life and Autonomy, Social Relationships, Emotions, and Physical Problems. Linear mixed-effects analyses revealed that, among patients younger than 60 years, the scores of the Cognition, Self, Daily Life and Autonomy, and Social Relationships domains significantly increased 6 months after injury; furthermore, their scores of the Cognition, Self, and Daily Life and Autonomy significantly increased 12 months after injury. By contrast, among patients 60 years and older, the scores of these domains reduced from baseline to 6 and 12 months. No significant sex-based difference was observed in the changes in scores of any QOLIBRI domain. At 6 and 12 months post-injury, the scores of the Cognition, Emotions, and Physical Problems domains were significantly higher for patients with postconcussive symptoms than for those without these symptoms. Although multiple characteristics of patients significantly affected their baseline scores on the 6 domains of the QOLIBRI, only age and postconcussive symptoms were significantly associated with longitudinal changes in their scores 6 and 12 months after mTBI.

Some Evidence That Truth-Tellers Are More Attractive Than Liars.

Despite the prevalence of deception, people rarely doubt others' sincerity. However, indirect evaluations of liars and truth-tellers may differ even in the absence of suspicion about veracity. Across three studies, we provide evidence for the truth attraction effect in two samples of target stimuli and three samples of participant judges. Target people are perceived as more attractive when telling the truth versus when they lie, an effect mediated by target warmth and openness. The truth attraction effect is stronger for female targets (vs. males); however, it is unaffected by the gender of the judge. Findings suggest people may be more likely to approach truth-tellers versus liars, even when not actively judging veracity. We discuss the challenges and benefits of treating both targets and participants as random factors in linear mixed-effect analyses and join the chorus of calls to increase the number of target stimuli in deception research.

Seasonal pattern and depression outcomes from repetitive transcranial magnetic stimulation

Individuals with major depressive disorder (MDD) may exhibit a seasonal pattern. The impact of a seasonal pattern in depressive symptoms on rTMS outcomes is unexplored. A retrospective analysis was performed on patients with MDD receiving open-label high frequency rTMS to the left dorsolateral prefrontal cortex. Having a seasonal pattern was defined as scoring ≥ 12 on the Personal Inventory for Depression and Seasonal Affective Disorder (PIDS). Primary outcomes included improvement in the Hamilton Depression Rating Scale (HAMD) and remission. Secondary analyses included the use of the self-rated Quick Inventory of Depressive Symptomatology (QIDS) to assess for changes in atypical neurovegetative symptoms. Multiple linear regression, multiple logistic regression, and linear mixed effects analyses were performed. 46 % (58/127) of the sample had a seasonal pattern. Seasonal pattern did not significantly influence improvement in HAMD (PIDS < 12, 7.8, SD 5.9; PIDS ≥ 12, 10.4, SD 4.9 or remission (PIDS < 12, 30 %; PIDS ≥ 12, 34 %). There were equivalent degrees of improvement in atypical neurovegetative symptoms over time as assessed using the QIDS. Depression with seasonal pattern was found to respond to rTMS treatment similarly to depression without seasonal pattern, suggesting that this may be a viable treatment for this group.

An quantitative analysis of Punjabi tones

Punjabi has three tones, the falling and the rising tones developed due to the historically lost voiced aspirated consonants and word-final glottal fricative /ɦ/, and the default tone occurred elsewhere. While there has been some experimental research on Punjabi tones, there have been limitations due few stimuli and speakers. The main aim of the current study was to provide a phonetic examination of the fundamental frequency (f0) patterns across a large number of Punjabi words produced by multiple speakers. The experiment was conducted online using 24 native speakers (9F, 15M) of Indian Punjabi. The list of stimuli contained 66 monosyllabic words (default = 18, falling = 15, rising = 33) with either /a/ or /ə/. The speakers were recorded producing the stimuli in carrier and natural sentence environments. Linear mixed effects analyses were conducted on six f0 measures: the onset, mid, and offset of the vowel, the f0 range (MaxF0-MinF0), and the f0 trajectory in the first (MidF0-BegF0) and final (EndF0-MidF0) halves of the vowel. The results confirmed three distinct pitch curves for the three tones. Each of the three tones were distinguished from one another for the onset f0 and the EndF0-MidF0 measures. Vowel quality influenced tone realization. Between-speaker and word variation was observed.

Neutrophil-to-lymphocyte ratio is an independent predictor for neurological disability in patients with idiopathic transverse myelitis

IntroductionThe neutrophil-to-lymphocyte ratio (NLR) has been found to be useful in the prognostication of immune-mediated neurological disorders because it roughly reflects the systemic innate immune response compared to the adaptive immune response. However, studies on the validity of NLR in demyelinating disorders of the central nervous system have shown conflicting results. Therefore, we aimed to investigate NLR in the idiopathic transverse myelitis (ITM) cohort.MethodsWe retrospectively analyzed the cohort data of patients with ITM between January 2006 and February 2020. The medical data of all patients with myelitis were reviewed to exclude patients with disease-associated myelopathy according to predefined exclusion criteria. The relationship between the natural log-transformed NLR (lnNLR) and the clinical, paraclinical, and imaging data was evaluated. Factors associated with neurological disability were analyzed using a linear mixed-effects model. Predictive factors for moderate-to-severe neurological disability (Expanded Disability Status Scale [EDSS] score ≥ 4) were investigated.ResultsA total of 124 participants were included in the analysis. The lnNLR correlated with EDSS and lesion length. Linear mixed-effects analysis showed that age, lesion length, and lnNLR were independently associated with neurological disabilities. Multivariable logistic regression revealed that lnNLR (odds ratio [OR] = 4.266, 95% confidence interval [CI] = 1.220–14.912, p = 0.023) and lesion length (OR = 1.848, 95% CI = 1.249–2.734, p = 0.002) were independent predictive factors of the worst neurological disability.ConclusionNLR may be used as an independent prognostic factor for predicting poor neurological outcomes in patients with ITM.

Compensatory health beliefs in women in the first, second and third trimester of pregnancy.

Compensatory health beliefs may serve as one of many self-regulatory strategies that individuals employ to maintain healthy lifestyles. Past research with samples from a general population has shown, however, that compensatory beliefs are ineffective in this regard and may even lead to inaction in future health-related behaviors such as eating healthily or being active. To better understand this phenomenon, in the present study, changes in compensatory health beliefs regarding various life domains were examined in a group of pregnant women. In a longitudinal study design, 166 women completed questionnaires in the first (t1), the second (t2), and the third (t3) trimester of their pregnancies. We assessed the level of their self-control as a trait (t1, t2, t3), compensatory health beliefs (t1, t2, t3), and unhealthy snacking (t3). As predicted, self-control as a trait decreased and the levels of compensatory beliefs increased over time. A linear mixed effects analysis showed that self-control was the best predictor of compensatory beliefs in the third trimester. Finally, compensatory health beliefs in the third trimester mediated the effect of self-control at the beginning of pregnancy on unhealthy snacking in the third trimester. It appears important to support pregnant women in opting for constructive self-regulatory strategies, especially in their final trimesters, when coping resources are exhausted by the challenges of this period.

Relationships between blood chromium exposure and liver injury: Exploring the mediating role of systemic inflammation in a chromate-exposed population

Hexavalent chromium and its compounds are prevalent pollutants, especially in the work environment, pose a significant risk for multisystem toxicity and cancers. While it is known that chromium accumulation in the liver can cause damage, the dose-response relationship between blood chromium (Cr) and liver injury, as well as the possible potential toxic mechanisms involved, remains poorly understood. To address this, we conducted a follow-up study of 590 visits from 305 participants to investigate the associations of blood Cr with biomarkers for liver injury, including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and direct bilirubin (DBIL), and to evaluate the mediating effects of systemic inflammation. Platelet (PLT) and the platelet-to-lymphocyte ratio (PLR) were utilized as biomarkers of systemic inflammation. In the linear mixed-effects analyses, each 1-unit increase in blood Cr level was associated with estimated effect percentage increases of 0.82% (0.11%, 1.53%) in TBIL, 1.67% (0.06%, 3.28%) in DBIL, 0.73% (0.04%, 1.43%) in ALT and 2.08% (0.29%, 3.87%) in AST, respectively. Furthermore, PLT mediated 10.04%, 11.35%, and 10.77% increases in TBIL, DBIL, and ALT levels induced by chromate, respectively. In addition, PLR mediated 8.26% and 15.58% of the association between blood Cr and TBIL or ALT. These findings shed light on the mechanisms underlying blood Cr-induced liver injury, which is partly due to worsening systemic inflammation.

Effectiveness of Internet-delivered self-help acceptance and commitment therapy (iACT) on nurses' obsessive-compulsive symptoms and sleep quality: A randomized controlled trial with 3-month follow-up

BackgroundFrontline nurses suffered unprecedented mental distress during the COVID-19 pandemic. It's essential to explore new and more accessible alternatives to improve the availability of psychological treatments. This study aimed to investigate the influence of online self-help iACT linear intervention and iACT loop intervention on sleep quality (SQ), obsessive-compulsive symptoms (OCS), and psychological flexibility (PF) in nurses. MethodsA randomized controlled trial was conducted at a hospital in China. 602 participants were randomly assigned to the iACT linear intervention, iACT loop intervention, or wait list control group, and required to complete the questionnaires of OCS, PF and SQ. The linear mixed effects analysis (LMM) was used to analyze the impact of the intervention on outcome variables. ResultsLMM analyses demonstrated that both two intervention had significant improvement on OCS (t = −38.235, p < 0.001), PF (t = 28.156, p < 0.001), as well as SQ (t = −16.336, p < 0.001). There were significant differences between the linear group and loop group on the PF in T2 (t = −8.271, p < 0.001), T3 (t = −8.366, p < 0.001), T4 (t = −8.302, p < 0.001), with the iACT loop model (Cohen's d = 1.652) showing a slight advantage over the iACT linear model (Cohen's d = 1.134). ConclusionsThe findings indicate that two interventions positively impact OCS, PF, and SQ. Compared to the iACT linear psychotherapy model, the iACT loop model shows greater effectiveness in enhancing PF, making it helpful to promote significant improvements in psychotherapy planning.

Correspondence of mean apparent propagator MRI metrics with phosphorylated tau and astrogliosis in chronic traumatic encephalopathy.

Chronic traumatic encephalopathy is a neurodegenerative disease that is diagnosed and staged based on the localization and extent of phosphorylated tau pathology. Although its identification remains the primary diagnostic criteria to distinguish chronic traumatic encephalopathy from other tauopathies, the hyperphosphorylated tau that accumulates in neurofibrillary tangles in cortical grey matter and perivascular regions is often accompanied by concomitant pathology such as astrogliosis. Mean apparent propagator MRI is a clinically feasible diffusion MRI method that is suitable to characterize microstructure of complex biological media efficiently and comprehensively. We performed quantitative correlations between propagator metrics and underlying phosphorylated tau and astroglial pathology in a cross-sectional study of 10 ex vivo human tissue specimens with 'high chronic traumatic encephalopathy' at 0.25 mm isotropic voxels. Linear mixed effects analysis of regions of interest showed significant relationships of phosphorylated tau with propagator-estimated non-Gaussianity in cortical grey matter (P = 0.002) and of astrogliosis with propagator anisotropy in superficial cortical white matter (P = 0.0009). The positive correlation between phosphorylated tau and non-Gaussianity was found to be modest but significant (R2 = 0.44, P = 6.0 × 10-5) using linear regression. We developed an unsupervised clustering algorithm with non-Gaussianity and propagator anisotropy as inputs, which was able to identify voxels in superficial cortical white matter that corresponded to astrocytes that were accumulated at the grey-white matter interface. Our results suggest that mean apparent propagator MRI at high spatial resolution provides a means to not only identify phosphorylated tau pathology but also detect regions with astrocytic pathology and may therefore prove diagnostically valuable in the evaluation of concomitant pathology in cortical tissue with complex microstructure.

Configurations of mother-child and father-child attachment relationships as predictors of child language competence: An individual participant data meta-analysis.

An individual participant data meta-analysis was conducted to test pre-registered hypotheses about how the configuration of attachment relationships to mothers and fathers predicts children's language competence. Data from seven studies (published between 1985 and 2014) including 719 children (Mage : 19.84 months; 51% female; 87% White) were included in the linear mixed effects analyses. Mean language competence scores exceeded the population average across children with different attachment configurations. Children with two secure attachment relationships had higher language competence scores compared to those with one or no secure attachment relationships (d = .26). Children with two organized attachment relationships had higher language competence scores compared to those with one organized attachment relationship (d = .23), and this difference was observed in older versus younger children in exploratory analyses. Mother-child and father-child attachment quality did not differentially predict language competence, supporting the comparable importance of attachment to both parents in predicting developmental outcomes.

Quantifying Muscle Size Asymmetry in Adolescent Idiopathic Scoliosis Using Three-dimensional Magnetic Resonance Imaging.

This is a case-control study of prospectively collected data. To quantify paraspinal muscle size asymmetry in adolescent idiopathic scoliosis (AIS) and determine if this asymmetry is (i) greater than observed in adolescent controls with symmetrical spines; and (ii) positively associated with skeletal maturity using Risser grade, scoliosis severity using the Cobb angle, and chronological age in years. AIS is a three-dimensional deformity of the spine which occurs in 2.5% to 3.7% of the Australian population. There is some evidence of asymmetry in paraspinal muscle activation and morphology in AIS. Asymmetric paraspinal muscle forces may facilitate asymmetric vertebral growth during adolescence. An asymmetry index [Ln(concave/convex volume)] of deep and superficial paraspinal muscle volumes, at the level of the major curve apex (Thoracic 8-9 th vertebral level) and lower-end vertebrae ( LEV , Thoracic 10-12 th vertebral level), was determined from three-dimensional Magnetic Resonance Imaging of 25 adolescents with AIS (all right thoracic curves), and 22 healthy controls (convex=left); all female, 10 to 16 years. Asymmetry index of deep paraspinal muscle volumes was greater in AIS (0.16±0.20) than healthy spine controls (-0.06±0.13) at the level of the apex ( P <0.01, linear mixed-effects analysis) but not LEV ( P >0.05). Asymmetry index was positively correlated with Risser grade ( r =0.50, P <0.05) and scoliosis Cobb angle ( r =0.45, P <0.05), but not age ( r =0.34, P >0.05). There was no difference in the asymmetry index of superficial paraspinal muscle volumes between AIS and controls ( P >0.05). The asymmetry of deep apical paraspinal muscle volume in AIS at the scoliosis apex is greater than that observed at equivalent vertebral levels in controls and may play a role in the pathogenesis of AIS.

Edaphic and epigeic macrofauna responses to land use change in Brazil

The expansion of sugarcane (Saccharum spp.) over extensive pasture areas has been one of the primary land-use change (LUC) scenarios in central-southern Brazil. However, LUC could negatively affect soil fauna along with the multiple functions and services associated with these organisms. Numerous groups of macroinvertebrates inhabiting the soil surface (i.e., epigeic) or the soil profile (i.e., edaphic) are fundamental for litter fragmentation, soil structuring and stabilization, water infiltration, biogeochemical cycling. In this study, both the edaphic and epigeic macrofauna communities were surveyed simultaneously to assess responses induced by the expansion of sugarcane cultivation over extensive pastures and to investigate whether the magnitude of such responses to LUC differs according to the community niche (i.e., soil profile versus surface). We hypothesized that LUC to a semi-perennial crop such as sugarcane would increase the density and diversity of the edaphic macrofauna, while the epigeic community would be negatively affected by LUC due to drastic changes in surface litter. The studied areas were two sites varying in soil texture (i.e., clay versus sandy soils) each including the following land uses: i) native vegetation, ii) extensive pasture, iii) newly planted sugarcane crop (sugarcane); and iv) established sugarcane (sugarcane ratoon). To evaluate edaphic macrofauna the TSBF methodology was adopted, while pitfall traps were installed at the same sampling points to collected epigeic macrofauna. The evaluated community attributes were density, Shannon diversity index, evenness index, richness of soil macrofauna taxa, as well as the chemical and physical attributes of the soil. Linear mixed effects analysis showed that LUC affected the relative abundance of edaphic (Land use p = 0.1191 r2marginal = 0.28, r2conditional = 0.33) and epigeic (Land use p = 0.0176; r2marginal = 0.22, r2conditional = 0.32) macroinvertebrates. Both groups showed the greatest density of organisms under native vegetation. Coleoptera and earthworms were associated with pasture areas, especially in clayey soil. Response ratios of LUC effects on macrofauna showed stronger responses of the epigeic compared to edaphic macrofauna, indicating a greater sensitivity of surface-dwelling organisms and their functions to disturbances such as those caused by LUC. In general, the density and diversity of macrofauna exhibited a positive correlation with soil organic matter, microbial carbon and nitrogen, macroporosity, and total porosity, and a negative correlation with soil density (p < 0.05). Also, the conversion of pasture to sugarcane cultivation (planting) causes significant macrofauna losses, particularly, in the clay soil. The cultivation of ratoon sugarcane led to a reduction of the density, taxonomic richness, diversity, and evenness of macrofauna. Given the importance of epigeic macroinvertebrates for litter fragmentation and decomposition, these results may indicate a rapid loss of key soil functions related to decomposition and carbon and nutrient cycling following LUC.

Impact of traffic-related air pollution on the blood pressure response to exercise in individuals with hypertension

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Natural Sciences and Engineering Research Council of Canada and B.C. Sports &amp; Exercise Medicine Research Foundation. Background The epidemiologic evidence suggests that the health benefits of exercise in healthy adults outweigh the adverse effects of air pollution in all but the most extreme concentrations. However, no studies have examined the acute response to exercise in air pollution in individuals with hypertension, a subgroup particularly susceptible to the cardiovascular effects of air population. Purpose The purpose of this study was to determine the impact of traffic-related air pollution on the acute cardiovascular response to exercise in patients with hypertension. We hypothesized that exposure to higher levels of traffic-related air pollution during exercise would attenuate, but not eliminate, acute post-exercise reductions in blood pressure and arterial stiffness. Methods Fourteen patients with hypertension (62.4±6.8 years; 81% male) completed a real-world, randomized, crossover study. Two 30-minute exercise bouts at 40-59% heart rate reserve were performed: once along a commercial street (high traffic) and once in an urban plaza (low traffic). Blood pressure (BP) and arterial stiffness (i.e., carotid-femoral pulse wave velocity [cfPWV]) were examined prior to, 30 minutes after, and 2 hours following exercise. 24-hour ambulatory BP monitoring was immediately completed following each visit. Black carbon, noise, relative humidity, and temperature were measured during each exercise bout (Figure 1). Results No differences were found for baseline cardiovascular measures between high and low traffic visits. At 30 minutes and 2 hours post-exercise, systolic BP was significantly reduced relative to baseline in the low-traffic condition only; diastolic BP was not significantly reduced at any timepoint. Based on linear mixed-effects analyses, exercising at the low traffic site was associated, relative to the high traffic site, with a significant (p = 0.04) reduction in systolic BP (-4.30 mm Hg [95% CI -8.09 to -0.54]) up to 2 hours following exercise after adjusting for exercise intensity, temperature, and noise; no differences were found for diastolic BP (-1.56 mm Hg [95% CI -4.87 to 1.83], p = 0.39). Each interquartile increase in black carbon (1168 ng/m³) was significantly associated with a 2.33 mm Hg (95% CI 0.37 to 4.17) increase in systolic BP up to 2 hours following exercise. No associations were observed between traffic site and BP for any ambulatory periods (i.e., 24-hour average, daytime, nighttime, or evening). The acute cfPWV response to exercise was also similar between traffic sites (p &amp;gt; 0.05). Conclusion Our findings suggest that exposure to traffic-related air pollution during exercise may adversely impact the beneficial short-term BP response to exercise in patients with hypertension. While the long-term implications of these changes to the acute BP response to exercise must be further explored, patients with hypertension can employ the prudent strategy of maximizing their distance from major roadways when exercising.

CE-452779-3 RANDOMIZED PLACEBO-CONTROLLED TRIAL OF FLECAINIDE IN PATIENTS WITH ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited arrhythmia disorder with a high risk of ventricular tachycardia (VT) or ventricular fibrillation (VF), and implantable cardioverter defibrillators (ICD) remain the palliative therapy of choice. We conducted an NIH-funded pilot clinical trial hypothesizing flecainide administration is more effective than placebo in reducing the burden of ventricular premature beats (VPBs) in ARVC patients. The study was designed as a randomized double-blinded placebo-controlled crossover trial in ARVC patients with administration of 100 mg bid of flecainide or matching placebo for 4 weeks each with a washout period. The primary specific aim was to determine whether flecainide administration is associated with a significant reduction of number of VPBs in comparison to placebo, measured on 7-day Zio-Patch ECG monitoring. Inclusion criteria required ARVC diagnosis with the 2010 ARVC Task Force Criteria at the age of at least 18 years, implanted ICD, and over 500 VPBs on a diagnostic 24-hour Holter recording. Patients were required to be treated with beta-blockers. Patients on other antiarrhythmic treatment required washout with reconfirmation of over 500 VPBs per 24 hour off antiarrhythmic medication. The effect of flecainide on log2(VPB rate) was analyzed using a weighted linear mixed effects analysis of variance model with fixed effects for treatment and period and a random effect for subject, with wights proportional to teh Zio-Patch monitoring time. There were 22 patients with ARVC and an ICD enrolled with a mean age 45+/-13 years, including 12 females. There were 19 patients with at least one Zio-Patch recording and 17 with both recordings. The Table includes details of arrhythmias on placebo and on flecainide. The mean and median number of VPBs/day was significantly lower on flecainide than placebo. At least 50% reduction in VPBs/day was observed in 79% and at least 75% reduction in 53% of patients. The primary analysis showed that flecainide reduced the VPB rate by 72% (p < 0.0001, 95% CI: 56-82%), adjusted for the period effect. There were 2 subjects with pro-arrhythmic response, but flecainide was safe for most of study patients. This is the first randomized clinical trial testing antiarrhythmic management in ARVC patients. Flecainide signficantly reduced the VPB rate and NSVT/VT/VF rate supporting clinical use of this medication in ARVC patients.

Disturbances in fear extinction learning after mild traumatic brain injury in mice are accompanied by alterations in dendritic plasticity in the medial prefrontal cortex and basolateral nucleus of the amygdala

Mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) have emerged as the signature injuries of the U.S. veterans who served in Iraq and Afghanistan, and frequently co-occur in both military and civilian populations. To better understand how fear learning and underlying neural systems might be altered after mTBI, we examined the acquisition of cued fear conditioning and its extinction along with brain morphology and dendritic plasticity in a mouse model of mTBI. To induce mTBI in adult male C57BL/6J mice, a lateral fluid percussive injury (LFP 1.7) was produced using a fluid pulse of 1.7 atmosphere force to the right parietal lobe. Behavior in LFP 1.7 mice was compared to behavior in mice from two separate control groups: mice subjected to craniotomy without LFP injury (Sham) and mice that did not undergo surgery (Unoperated). Following behavioral testing, neural endpoints (dendritic structural plasticity and neuronal volume) were assessed in the basolateral nucleus of the amygdala (BLA), which plays a critical sensory role in fear learning, and medial prefrontal cortex (mPFC), responsible for executive functions and inhibition of fear behaviors. No gross motor abnormalities or increased anxiety-like behaviors were observed in LFP or Sham mice after surgery compared to Unoperated mice. We found that all mice acquired fear behavior, assessed as conditioned freezing to auditory cue in a single session of 6 trials, and acquisition was similar across treatment groups. Using a linear mixed effects analysis, we showed that fear behavior decreased overall over 6 days of extinction training with no effect of treatment group across extinction days. However, a significant interaction was demonstrated between the treatment groups during within-session freezing behavior (5 trials per day) during extinction training. Specifically, freezing behavior increased across within-session extinction trials in LFP 1.7 mice, whereas freezing behavior in control groups did not change on extinction test days, reflecting a dissociation between within-trial and between-trial fear extinction. Additionally, LFP mice demonstrated bilateral increases in dendritic spine density in the BLA and decreases in dendritic complexity in the PFC. The translational implications are that individuals with TBI undergoing fear extinction therapy may demonstrate within-session aberrant learning that could be targeted for more effective treatment interventions.

Student perceptions of behavior and discipline: a PBIS survey for student voice

Student voice is essential for PBIS, but a tool for gathering students’ perspectives of PBIS is not available in the literature. The purpose of this study was to develop and validate a universal–level PBIS survey for students, the Student Perceptions of Behavior and Discipline (StPBD). This survey was designed to mobilize student engagement and guide implementation with cultural and contextual fit. Survey development was informed by literature review, feedback from users and researchers, pilot tests, and exploratory and confirmatory factor analysis. Analyses of items designed to measure aspects of school climate, student–staff relationships, and family connections confirmed these three distinct factors. Linear mixed–effect analyses revealed significant relationships between the survey, student perceptions of PBIS practices in the school, school level, discipline, and gender identity.

Under pressure: What individual characteristics lead to performance of high-quality chest compressions during CPR practice sessions?

AimDespite well-established protocols for cardiopulmonary resuscitation training, performance during real-life cardiac arrests can be suboptimal. Understanding personal characteristics which could influenceperformance of high-quality chest compressions could provide insight into the practice-performance gap. This study examined chest compressionperformance, while employing feedback and introducing code team sounds as an anxiety-inducing factor in registered nurses using a cardiopulmonary resuscitation training manikin. MethodsParticipants included 120 registered nurses with basic life support certification randomized to one of the following groups: no feedback and no code team sounds, feedback without code team sounds, or feedback with code team sounds. Chest compression sessions occurred at baseline, 30-days and 60-days. Demographic variables and anxiety level were also collected. The primary outcome was chest compression performance, defined as average percent of time with correct rate and percent with correct depth as captured by the defibrillator. Statistical analysis included linear mixed effects analysis. ResultsThe effect of feedback on chest compression performance depended on the value of other parameters. The benefit of feedback on the primary outcome depended on: age, with feedback less beneficial among older participants (p = 0.0413); and time, with feedback more beneficial with repetition (p = 0.011). These interactions also affected the outcome percent of time with correct compression depth. Increased anxiety was associated with decreased percent correct compression depth (p < 0.001). ConclusionFeedback emerged as important in determining chest compression performance. Chest compression quality was limited by the performer’s age and anxiety level. Future research should focus on identifying factors related to individual characteristics which may influence chest compression performance.