Intestinal injury in paracetamol overdose (ATOM-8)

BACKGROUND AND AIM

Paracetamol, a widely used medication, is known for its delayed hepatotoxicity in cases of overdose. However, the potential for intestinal toxicity resulting from very high paracetamol concentrations during absorption is not well explored. This study aims to investigate the presence of intestinal toxicity and its correlation with observations in early and late paracetamol toxicity.

METHODS

Serial samples of 30 patients with acute paracetamol overdose (> 10 g or 200 mg/kg) were prospectively tested. Markers of enterocyte damage, including plasma intestinal fatty acid binding protein (IFABP) and selected gut-related microRNAs (miR-21, miR-122, miR-194, and miR-215), were analyzed. Sub-analysis was performed on patients presenting with hyperlactatemia defined as a lactate greater than 2 mmol/L within 12 h post ingestion.

RESULTS

In paracetamol overdose patients, median plasma IFABP was significantly elevated compared with healthy controls (720 μg/L [interquartile range, IQR, 533-1644] vs 270 μg/L [IQR 153-558], P < 0.001). Four patients had early hyperlactatemia and had significantly higher median plasma IFABP compared with those without early hyperlactatemia (3028 μg/L [IQR 1399-3556] vs 574 μg/L [IQR 526-943], P = 0.007). Furthermore, two microRNAs (miR-122 and miR-215) were downregulated in early hyperlactatemia (P = 0.019 and P = 0.006, respectively). Plasma IFABP concentrations correlated with paracetamol concentration (Spearman's r = 0.55) and lactate (r = 0.60).

CONCLUSIONS

Paracetamol overdose causes concentration-related intestinal toxicity, and this is a possible explanation for the early hyperlactatemia syndrome. Intestinal toxicity has potential impacts on pharmacokinetics of other agents ingested and on the evolution of hepatotoxicity. Further studies are required to explore the mechanisms and prognostic implications of intestinal toxicity.

Mechanisms underlying the prolonged activation of the genioglossus following arousal from sleep

STUDY OBJECTIVES

Transient arousal from sleep has been shown to elicit a prolonged increase in genioglossus muscle activity that persists following the return to sleep and which may protect against subsequent airway collapse. We hypothesized that this increased genioglossal activity following return to sleep after an arousal is due to persistent firing of inspiratory-modulated motor units (MUs) that are recruited during the arousal.

METHODS

Thirty-four healthy participants were studied overnight while wearing a nasal mask with pneumotachograph to measure ventilation and with 4 intramuscular genioglossus EMG electrodes. During stable N2 and N3 sleep, auditory tones were played to induce brief (3-15s) AASM arousals. Ventilation and genioglossus MUs were quantified before the tone, during the arousal and for 10 breaths after the return to sleep.

RESULTS

A total of 1089 auditory tones were played and gave rise to 239 MUs recorded across arousal and the return to sleep in 20 participants (aged 23 ± 4.2 years and BMI 22.5 ± 2.2 kg/m2). Ventilation was elevated above baseline during arousal and the first post-arousal breath (p < .001). Genioglossal activity was elevated for five breaths following the return to sleep, due to increased firing rate and recruitment of inspiratory modulated MUs, as well as a small increase in tonic MU firing frequency.

CONCLUSIONS

The sustained increase in genioglossal activity that occurs on return to sleep after arousal is primarily a result of persistent activity of inspiratory-modulated MUs, with a slight contribution from tonic units. Harnessing genioglossal activation following arousal may potentially be useful for preventing obstructive respiratory events.

Evaluating the programme and behavior change theories of a community alcohol education intervention in rural Sri Lanka: a study protocol

Risky alcohol use is a major public health problem globally and in Sri Lanka. While a reduction in alcohol consumption can result in physical, mental, and social benefits, behaviour change is difficult to achieve. Effective, context-adapted interventions are required to minimise alcohol-related harm at a community level. THEATRE is a complex, community-based intervention evaluating whether a promising Sri Lankan pilot study that utilised arts-based research to moderate alcohol use can be scaled up. While the scaled-up pilot study protocol is presented elsewhere, the aim of this protocol paper is to describe the intervention programme theory and evaluation design, and modifications made to the study resulting from COVID-19 and the financial crisis. Drawing on the Behaviour Change Wheel (BCW) and Theoretical Domains Framework, behaviour change theories are presented with potential pathways to guide implementation and evaluation. Alcohol consumption patterns and context of drinking is detailed. The multifaceted intervention targets individuals and communities using arts-based interventions. Four of nine BCW functions are employed in the design of the intervention: education, persuasion, modelling and enablement, and training. Modifications made to the study due to COVID-19 and the financial crisis are described. Ethical approval was obtained from the Ethics Review Committee, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka (ERC/2018/21-July 2018 and Feb 2022) and the University of Sydney (2019/006). Findings will be disseminated locally to community members and key stakeholders and via international peer-reviewed publications.

Has there been an increase in nitrous oxide use and associated harms in Australia? An analysis of triangulated data sources, 2003-2020

BACKGROUND

There is growing concern, globally, regarding use of nitrous oxide (N2O) for intoxication purposes. This paper aims to examine trends in: (i) past six month N2O use among a sample of people who use regularly use ecstasy and/or other illicit stimulants (2003-2020); (ii) volume of N2O-related Google searches and social media posts (2009-2020); and (iii) N2O-related calls to Poisons Information Centres (PIC) (2004-2020).

METHODS

Data were obtained from annual interviews with sentinel samples of Australians aged ≥16 years who used ecstasy and/or other illicit stimulants ≥monthly and resided in a capital city (∼800 each year); Google search activity; social media posts; and exposure calls to four PIC.

RESULTS

Among samples of people who regularly use ecstasy and/or other illicit stimulants, past six-month N2O use increased 10% each year from 2009 to 2020, with the sharpest increase observed between 2015 and 2018 (25.4% p/year; 95% CI: 14.6-37.1). Frequency and quantity of N2O use remained stable and low. Google search probabilities increased by 1.8% each month from January 2009 and December 2019 (95% CI: 1.5-2.2), with the sharpest increase observed between July 2016 to December 2017 (6.0% p/month; 95% CI: 4.4-7.5). Social media posts increased 2.0% per month from January 2009 and December 2019 (95% CI: 1.1-3.0), with the sharpest increase observed between March and October 2017 (19.2% p/month; 95% CI: 1.7-39.7). The number of N2O-related calls to Australian PIC increased sixfold between 2016 (16) and 2020 (111).

CONCLUSIONS

Triangulation of various data sources indicate significant shifts in N2O use and harms in Australia. This includes increases in use, Google searches and social media posts, although these have plateaued in recent years, coupled with increased rates of harm. These findings correspond with evidence of a global increase in N2O use and harm, highlighting the need for education of both people who use N2O and health professionals.

Duplication errors due to brand name confusion; It is not always the name-Short case series

Confusion of drug names has been identified as a leading cause of medication errors and potential iatrogenic harm. Most of these errors occur because of look-alike or sound-alike drugs. This case series gives examples of duplication errors due to brand confusion, where there are no similarities in the names.

Measurement of an intestinal biomarker during poisonings from select toxicants and toxins

INTRODUCTION

Intestinal toxicity can occur following ingestion of various drugs, chemicals, and toxins. Intestinal fatty acid binding protein is a cytosolic protein specific to intestinal epithelial cells released into the systemic circulation following intestinal injury. Understanding intestinal toxicity in poisoning has the potential to explain mechanisms of toxicity and gastrointestinal symptoms.

METHODS

Plasma samples were retrospectively analysed for intestinal fatty acid binding protein in 25 healthy controls and in those poisoned with Gloriosa superba (n = 18), Thevetia peruviana (n = 26), organophosphates (in various solvents) (n = 17), paracetamol (n = 14), glyphosate (n = 20), 2-methyl-4-chlorophenoxyacetic acid (n = 18) and propanil (n = 19).

RESULTS

Median peak plasma intestinal fatty acid binding protein concentrations were significantly higher in patients poisoned with Gloriosa superba (2,994.1 µg/L; interquartile range 600.0-5,158.2, P < 0.001), Thevetia peruviana (1,292.5 µg/L; interquartile range 760.3 - 2,076.2; P < 0.001), glyphosate (1,803.6 µg/L; interquartile range 225.7-8,927.7; P < 0.001), 2-methyl-4-chlorophenoxyacetic acid (1,236.2 µg/L; interquartile range 192.6 - 1,709.7; P = 0.010), paracetamol (1,066.5 µg/L; interquartile range 512.9 - 1,336.9; P = 0.035), and organophosphate poisoning (729.8 µg/L; interquartile range 431.5 - 1,588.2; P = 0.046) than in healthy controls (221.6 µg/L; interquartile range 134.8 - 460.1). Median intestinal fatty acid binding protein was not statistically significantly increased compared to controls after propanil poisoning (630.0 µg/L; interquartile range 23.5 - 1,390.3; P = 0.423).

CONCLUSIONS

Our pilot study describes intestinal injury assessed by elevated plasma intestinal fatty acid binding protein concentrations following the ingestion of several poisons. This serves as a foundation for further exploration into enterocyte damage in toxicology.

π-Extended Pyrazinepyrene-Fused Zinc Phthalocyanines: Synthesis and Excited-State Charge Separation Involving Coordinated C60

A series of pyrazinepyrene-fused zinc phthalocyanines (ZnPc-Pyr_n) have been newly synthesized by reacting quinoxaline and the corresponding diamino-functionalized phthalocyanines as a new class of π-extended phthalocyanine systems. Bathochromically shifted absorption as a function of the number of pyrazinepyrene entities due to extended π-conjugation and quenched fluorescence due to the presence of fused pyrazinepyrene were witnessed. The electronic structures of these phthalocyanines were probed by systematic computational and electrochemical studies, while the excited-state properties were examined by pump-probe spectroscopies operating at the femto- and nanosecond time scales. Similar to the excited singlet lifetimes, the excited triplet states also revealed diminished lifetimes with an increased number of pyrazinepyrene entities. Further, the coordinatively unsaturated zinc in these molecules was coordinated with phenyl imidazole-functionalized fullerene, ImC₆₀, to form a new series of donor-acceptor conjugates. Upon full characterization of these conjugates, the occurrence of excited-state charge separation was established by transient pump-probe spectroscopy, covering wide temporal and spatial regions. The lifetime of the final charge-separated states was ∼2 ns and decreased with an increase in the number of fused pyrazinepyrene units.

Using the candidacy framework to conceptualize systems and gaps when developing infant mental health (IMH) services: A qualitative study

The development of infant mental health (IMH) services globally is still in its early stages. This qualitative study aims to understand the challenges of setting up IMH services and explores the views and experiences of 14 multi-disciplinary stakeholders who are part of the IMH implementation group in a large Scottish health board. Six major themes were identified through thematic analysis. This paper examines the most prominent theme "Systems" alongside the theme "Gaps in Current Service". The theoretical framework of "candidacy" is found to be a valuable way to conceptualize the complex systemic layers of micro, meso, and macro factors that contribute to the challenges of setting up services. At the micro level, key themes included the view that services must be accessible, individualized, and involve families. At the meso level, in line with the aims of the service, multiagency integration, aspects of early intervention, and clear operating conditions were all seen as important. Finally, at the macro level, perhaps the biggest challenge perceived by stakeholders is delivering a service that is entirely infant-focused. These findings will help inform policy makers about factors considered by professionals to be vital in the establishment of IMH services in Scotland and across the globe.

Community-based alcohol education intervention (THEATRE) study to reduce harmful effects of alcohol in rural Sri Lanka: design and adaptation of a mixed-methods stepped wedge cluster randomised control trial

INTRODUCTION

Alcohol consumption is a leading cause of mortality, morbidity and adverse social sequelae in Sri Lanka. Effective community-based, culturally adapted or context-specific interventions are required to minimise these harms. We designed a mixed-methods stepped wedge cluster randomised control trial of a complex alcohol intervention. This paper describes the initial trial protocol and subsequent modifications following COVID-19.

METHODS AND ANALYSIS

We aimed to recruit 20 villages (approximately n=4000) in rural Sri Lanka. The proposed intervention consisted of health screening clinics, alcohol brief intervention, participatory drama, film, and public health promotion materials to be delivered over 12 weeks.Following disruptions to the trial resulting from the Easter bombings in 2019, COVID-19 and a national financial crisis, we adapted the study in two main ways. First, the interventions were reconfigured for hybrid delivery. Second, a rolling pre-post study evaluating changes in alcohol use, mental health, social capital and financial stress as the primary outcome and implementation and ex-ante economic analysis as secondary outcomes.

ETHICS AND DISSEMINATION

The original study and amendments have been reviewed and granted ethical approval by Rajarata University of Sri Lanka (ERC/2018/21-July 2018 and February 2022) and the University of Sydney (2019/006). Findings will be disseminated locally in collaboration with the community and stakeholders.The new hybrid approach may be more adaptable, scalable and generalisable than the planned intervention. The changes will allow a closer assessment of individual interventions while enabling the evaluation of this discontinuous event through a naturalistic trial design. This may assist other researchers facing similar disruptions to community-based studies.

TRIAL REGISTRATION

The trial is registered with the Sri Lanka Clinical Trials Registry; https://slctr.lk/trials/slctr-2018-037.

Making Uncommon Sense of Laudable Research

In Australia, research resourcing might come from parties dedicated to addressing issues in the public interest, such as smoking cessation and alcohol regulation. The associations researchers have with those parties are regarded in quite different terms than, say, a research relationship that is forged with the tobacco or alcohol industries themselves. Agreeing to work with the latter ‘bad’ players would indubitably raise the liveliest of suspicions among fellow researchers, while associations with the former ‘good’ players are often regarded as in the service of good academic citizenship that helps bring about positive changes to the world, something that is often a key moral, as well as funding and publications, driver for researchers. We argue that such polar classification bears anthropological inspection and a radical rethink. The consequences of not so doing risk shutting down areas in which anthropological enquiry is urgently needed.

Mothers' ability to determine and measure paracetamol doses for children-a contrived observational study

Caregivers are primarily responsible for the administration of Over The Counter (OTC) medications in children. This study examines the mothers' ability to determine and measure paracetamol doses for children aged between 1 and 5 years. A contrived observational study was conducted for mothers of preschool aged children at two Public Health Midwifery (PHM) areas in Southern province, Sri Lanka. Stratified random sampling was used. Only 26.9% (n = 95, 95% CI = 22.5%-31.7%) of the 353 participants correctly determined and measured the doses of paracetamol. Errors were frequently made in both determining and measuring dose together (n = 113, 32.0%, 95% CI = 27.3%-37.1%), determining only (n = 94, 26.6%, 95% CI = 22.2%-31.5%) and measurement only (n = 51, 14.4%, 95% CI = 11.1%-18.5%). Dose determined errors were not significantly associated with maternal education, number of children in the family, total monthly income and age of the index child. Similarly measuring errors were not significantly associated with mothers' education, income of the family and number of children in the family. However, there was a weak positive correlation between measuring errors and age of the index child. The study suggests that mothers made errors when determining doses and measuring doses of paracetamol. Results emphasize importance of clear, concise guardian information leaflet and healthcare professionals' guidance to minimize dosing errors of child medication.

The influence of alcohol on genioglossus single motor units in men and women during wakefulness

NEW FINDINGS

What is the central question of this study? How does alcohol intake, which worsens obstructive sleep apnoea, alter motor control of the genioglossus muscle, an upper airway dilator, in healthy awake human volunteers, and does alcohol alter genioglossus muscle afterdischarge? What is the main finding and its importance? Alcohol consumption had a very minor effect on the activity of the genioglossus in healthy young individuals studied during wakefulness and did not alter afterdischarge, leaving open the possibility that alcohol worsens obstructive sleep apnoea via other mechanisms.

ABSTRACT

Alcohol worsens obstructive sleep apnoea (OSA). This effect is thought to be due to alcohol's depressant effect on upper airway dilator muscles such as the genioglossus, but how alcohol reduces genioglossal activity is unknown. The aim of this study was to investigate the effect of alcohol consumption on genioglossus muscle single motor units (MUs). Sixteen healthy individuals were studied on two occasions (alcohol: breath alcohol concentration ∼0.07% and placebo). They were instrumented with a nasal mask, four intramuscular genioglossal EMG electrodes, and an ear oximeter. They were exposed to 8-12 hypoxia trials (45-60 s of 10% O2 followed by one breath of 100% O2 ) while awake. MUs were sorted according to their firing patterns and quantified during baseline, hypoxia and recovery. For the alcohol and placebo conditions, global muscle activity (mean ± SD peak inspiratory EMG = 119.3 ± 44.1 and 126.5 ± 51.9 μV, respectively, P = 0.53) and total number of MUs recorded at baseline (68 and 67, respectively) were similar. Likewise, the peak discharge frequency did not differ between conditions (21.2 ± 4.28 vs. 22.4 ± 4.08 Hz, P = 0.09). There was no difference between conditions in the number (101 vs. 88, respectively) and distribution of MU classes during hypoxia, and afterdischarge duration was also similar. In this study, alcohol had a very minor effect on genioglossal activity and afterdischarge in these otherwise healthy young individuals studied while awake. If similar effects are observed during sleep, it would suggest that the worsening of OSA following alcohol may be related to increased upper airway resistance/nasal congestion or arousal threshold changes.

Motivational and myopic mechanisms underlying dopamine medication-induced impulsive-compulsive behaviors in Parkinson's disease

Introduction

Dopaminergic medications can trigger impulsive-compulsive behaviors (ICBs) in pre-disposed patients with Parkinson's disease (PD), but what this implies on a neurocognitive level is unclear. Previous findings highlighted potentially exacerbated incentive motivation (willingness to work for rewards) and choice impulsivity (preferring smaller, immediate rewards over larger, delayed rewards) in PD patients with ICBs (PD + ICBs).

Methods

To deeply understand this evidence, we studied 24 PD + ICBs and 28 PD patients without ICBs (PD-ICBs). First of all, patients underwent the assessment of impulsivity traits, mood, anxiety, and addiction condition. We further administered robust objective and subjective measures of specific aspects of motivation. Finally, we explored whether these processes might link to any heightened antisocial behavior (aggression and risky driving) in PD + ICBs.

Results

High levels of positive urgency trait characterized PD + ICBs. They choose to exert more effort for rewards under the conditions of low and medium reward probability and as reward magnitude increases. Findings on choice impulsivity show a great tendency to delay discounting in PD + ICBs, other than a high correlation between delay and probability discounting. In addition, we found what appears to be the first evidence of heightened reactive aggression in PD patients with ICBs. Exacerbated incentive motivation and delay discounting trended toward positively predicting reactive aggression in PD + ICBs.

Discussion

Our promising results suggest that there might be immense value in future large-scale studies adopting a transdiagnostic neurocognitive endophenotype approach to understanding and predicting the addictive and aggressive behaviors that can arise from dopaminergic medication in PD.

OUES from submaximal cardiopulmonary exercise

Introduction

Cardiopulmonary exercise testing (CPEX) provides valuable diagnostic and prognostic cardiopulmonary function data. However, in clinical setting a maximal test is not always achievable. The Oxygen Efficiency Uptake Slope (OUES) has been proposed as a possible submaximal measure of cardiopulmonary function as it remains relatively stable during the final quartile of the exercise test. This study explored the validity of OUES as a surrogate marker for cardiopulmonary function in the event of a submaximal test.

Methods

Four groups of subjects [128 healthy controls (73 M), 44 asymptomatic hypertensive (HT) patients (26 M), 67 adult cardiac congenital heart disease (ACHD) patients (44 M) and 35 Heart Failure with preserved Ejection Fraction (HFpEF) (10M) patients] were recruited after informed consent. All subjects underwent clinical assessment, resting ECG, blood pressure and spirometry prior to a treadmill CPEX to volitional exhaustion and a respiratory exchange ratio (RER) of at least 1.1 using the same testing protocol. Peak VO2 (ml/min) was recorded from the last 5s of the maximal test (RER=1.1) and OUES was calculated from complete (RER=1.1) and truncated (RER=0.9) gas exchange data. The linear relationships between absolute peak VO2 and OUES from complete and truncated gas exchange data were assessed using Pearson's correlation coefficient. Subsequently, the two correlations obtained in each patient group were compared. Statistical significance was set at p&lt;0.01.

Results

Mean and 95% confidence intervals of the peak VO2 for males and females in each decile of life examined in the 4 subject groups are shown in the Figure. Peak VO2 values achieved in each of the patient groups were significantly lower when matched for age and sex compared to healthy participants (HT p=0.006, ACHD patients p&lt;0.001 and HFpEF patients p&lt;0.001).

In all 4 groups there was a good correlation between absolute peak VO2 and the OUES at RER 1.1 (healthy volunteers r=0.910, p&lt;0.001, HT r=0.899, p&lt;0.001, ACHD r=0.816, p&lt;0.001 and HFpEF r=0.846, p&lt;0.001). Correlations were inferior for absolute peak VO2 and OUES at RER 0.9 (healthy volunteers r=0.74, p&lt;0.001, HT r=0.780, p&lt;0.001, ACHD r=0.651, p&lt;0.001 and HFpEF r=0.817, p&lt;0.001). Correlations between absolute peak VO2 vs OUES at RER of 1.1 and 0.9 were significantly different only for healthy controls (p=0.001, Z-score = −4.649), but not for HT (p=0.05, Z-score = −1.909), ACHD (p=0.04, Z-score = −2.080) or HFpEF (p=0.7, Z-score = −0.377) patients.

Conclusion

Our data support the use of submaximal OUES at an RER of 0.9 as a surrogate marker for absolute peak VO2 obtained at an RER of 1.1, especially in patients, in whom it can often be difficult to achieve maximal exercise.

Funding Acknowledgement

Type of funding sources: None.

The Association Between Problematic Use of Alcohol and Drugs and Repeat Self-Harm and Suicidal Ideation

Aims: We investigated the association between problematic use of alcohol and/or drugs (PUAD) and the incidence, urgency, and mode of discharge for a subsequent episode of self-harm (SH) or suicidal ideation (SI). Methods: This was a retrospective population-based cohort study of individuals admitted to hospital for an index episode of SH/SI (2010-2014) using linked data from hospital admissions and emergency department (ED) presentations. The outcome variables were (1) subsequent presentation to the ED for SH/SI, (2) triage category, and (3) mode of departure. Key predictors were PUAD. Results: In total, 23,007 individuals were admitted to hospital for an index SH/SI, of whom 8% had a subsequent presentation to an ED for SH/SI within a year. The odds of subsequent presentation was increased in those with problematic alcohol use (AOR 1.62, 95% CI 1.36, 1.92), drug use (AOR 1.28, 95% CI 1.07, 1.53), and mental health diagnoses (AOR 1.63, 95% CI 1.44, 1.85). Those with problematic alcohol use were more likely to be assigned to the most urgent triage categories (AOR 1.84, 95% CI 1.32, 2.56). Limitations: Defining SH and PUAD using administrative data is challenging, and the true prevalence is likely to be underestimated. Conclusion: The findings underscore the importance of drug health intervention as a key component of self-harm prevention.

Why is trust lower in Quebec? A cultural explanation

In this article, we provide a cultural explanation of a long-standing trust puzzle in Canada-Quebecers trust much less than their fellow Canadians. Specifically, we develop a novel approach to empirically assess the historical influence of the Catholic Church, using the Quiet Revolution (a period of abrupt modernization in Quebec) as a natural experiment. We find that older cohorts socialized prior to the Quiet Revolution are significantly less trusting-a distinctive trend that is most pronounced among Catholics. Conversely, in the rest of Canada older cohorts are more trusting, following the trend commonly found in other countries. Furthermore, measures of both religious beliefs and modernization account for a large part of the birth cohort trust gap in Quebec. The findings suggest that low trust in Quebec is rooted in the province's Catholic cultural heritage, but that the legacy of the Quiet Revolution is gradually changing the trust culture.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

8000-year doubling of Midwestern forest biomass driven by population- and biome-scale processes

Changes in woody biomass over centuries to millennia are poorly known, leaving unclear the magnitude of terrestrial carbon fluxes before industrial-era disturbance. Here, we statistically reconstructed changes in woody biomass across the upper Midwestern region of the United States over the past 10,000 years using a Bayesian model calibrated to preindustrial forest biomass estimates and fossil pollen records. After an initial postglacial decline, woody biomass nearly doubled during the past 8000 years, sequestering 1800 teragrams. This steady accumulation of carbon was driven by two separate ecological responses to regionally changing climate: the spread of forested biomes and the population expansion of high-biomass tree species within forests. What took millennia to accumulate took less than two centuries to remove: Industrial-era logging and agriculture have erased this carbon accumulation.

Research As Development: Book Forum

Book forum on 'Research as Development'

The evolving classifications and epidemiological challenges surrounding chronic migraine and medication overuse headache: a review

Changes in diagnostic criteria, for example, the various International Classification of Headache Disorders criteria, would lead to changes in the outcomes of epidemiological studies. International Classification of Headache Disorders-1 was based mainly on expert opinion, yet most of the diagnostic criteria were reliable and valid, but it did not include chronic migraine. In its second version, the classification introduced chronic migraine, but this diagnosis resembled more a high-frequency migraine rather than the actual migraine transformation process. It also introduced medication overuse headache, but it necessitated analgesic withdrawal and subsequent headache improvement to be diagnosed as such. Hence patients having medication overuse headache could only be diagnosed in retrospect, which was an awkward situation. Such restrictive criteria for chronic migraine and medication overuse headache omitted a high proportion of patients. International Classification of Headache Disorders-3 allows a diagnosis of medication overuse headache due to combination analgesics if taken for at least 10 days per month for more than three months. Hence the prevalence rate of medication overuse headache and chronic migraine can increase compared to the previous version of the headache classification. Different criteria have been used across studies to identify chronic migraine and medication overuse headache, and therefore the information acquired from previous studies using earlier criteria becomes uncertain. Hence much epidemiological research would need to be interpreted cautiously or repeated with the most updated criteria, since the subjects in studies that apply the latest criteria may be phenotypically different from those in older studies.

Physostigmine should be used more readily for antimuscarinic toxicity: PRO

Physostigmine is the preferred treatment for antimuscarinic toxicity. Its use has a clear biological rationale and is supported by extensive clinical use which demonstrated effectiveness and safety.

Charge-Transfer in Panchromatic Porphyrin-Tetracyanobuta-1,3-Diene-Donor Conjugates: Switching the Role of Porphyrin in the Charge Separation Process

Using a combination of cycloaddition-retroelectrocyclization reaction, free-base and zinc porphyrins (H₂ P and ZnP) are decorated at their β-pyrrole positions with strong charge transfer complexes, viz., tetracyanobuta-1,3-diene (TCBD)-phenothiazine (3 and 4) or TCBD-aniline (7 and 8), novel class of push-pull systems. The physico-chemical properties of these compounds (MP-Donor and MP-TCBD-Donor) have been investigated using a range of electrochemical, spectroelectrochemical, DFT as well as steady-state and time-resolved spectroscopic techniques. Ground-state charge transfer interactions between the porphyrin and the electron-withdrawing TCBD directly attached to the porphyrin π-system extended the absorption features well into the near-infrared region. To visualize the photo-events, energy level diagrams with the help of free-energy calculations have been established. Switching the role of porphyrin from the initial electron acceptor to electron donor was possible to envision. Occurrence of photoinduced charge separation has been established by complementary transient absorption spectral studies followed by global and target data analyses. Better charge stabilization in H₂ P derived over ZnP derived conjugates, and in phenothiazine derived over aniline derived conjugates has been possible to establish. These findings highlight the importance of the nature of porphyrins and second electron donor in governing the ground and excited state charge transfer events in closely positioned donor-acceptor conjugates.

The Emerging Drugs Network of Australia: A toxicosurveillance system of illicit and emerging drugs in the emergency department

OBJECTIVE

The unprecedented rise in synthetic drugs, many containing unknown toxic agents, has made timely analytical diagnosis more difficult, and has reduced the confidence of clinicians providing ED management to this population of patients. This has also impacted the quality of evidence informing harm reduction responses. The Emerging Drugs Network of Australia (EDNA) brings together emergency physicians, toxicologists and forensic laboratories to establish a standardised ED toxicosurveillance system in Australia.

METHODS

Blood analysis of intoxicated patients will be conducted by forensic laboratories to enable precise identification of the substances causing acute toxicity. This will be linked with clinical data collected at the time of ED presentation to enable analysis of the clinical effects and outcomes associated with different illicit and emerging drugs. Toxicological and clinical data collected across sentinel sites will align with a nationally endorsed minimum dataset.

RESULTS

EDNA's collaborative network will establish a national system of surveillance and reporting of illicit and emerging drugs causing acute toxicity. Standardisation of data collection recorded in a national clinical registry will provide more robust data on epidemiology and associated harms. This will facilitate the translation of clinical and toxicological evidence into timely, appropriate harm reduction and policy.

CONCLUSION

Our work represents a collaborative response to calls for more sophisticated data on emerging drug trends in Australia. EDNA will improve coordination between clinicians and analytical services by way of its standardised approach to surveillance and reporting.

The achilles heel of democracy? A macro cross-national assessment of the correlates of state legitimacy

This study investigates the macro-level correlates of subjective state legitimacy using a cross-national panel dataset of 82 countries from 1989 to 2014. It conducts the first comprehensive multivariate assessment of the effect of democracy, while also evaluating the effects of the nationalist principle of ethnic self-rule and state endogeneity (i.e. colonialism), net of controls. The findings suggest that-contrary to certain theories and earlier empirical studies-democracy has a strong and negative association with legitimacy, which is robust across different measures of democracy and model specifications. The results also provide some evidence that adhering to the nationalist principle is related to subjective state legitimacy, while suggesting that state endogeneity is not. Moreover, democracy is the strongest correlate of subjective state legitimacy whose effect becomes stronger-rather than weaker, as some predict-in the presence of controls. Preliminary analyses provide some support to the claim that the freedom of expression contributes to the negative democracy/state legitimacy relationship.

Identifying Predictors of University Students' Wellbeing during the COVID-19 Pandemic-A Data-Driven Approach

BACKGROUND

The COVID-19 pandemic has posed risks to public mental health worldwide. University students, who are already recognised as a vulnerable population, are at elevated risk of mental health issues given COVID-19-related disruptions to higher education. To assist universities in effectively allocating resources to the launch of targeted, population-level interventions, the current study aimed to uncover predictors of university students' psychological wellbeing during the pandemic via a data-driven approach.

METHODS

Data were collected from 3973 Australian university students ((median age = 22, aged from 18 to 79); 70.6% female)) at five time points during 2020. Feature selection was conducted via least absolute shrinkage and selection operator (LASSO) to identify predictors from a comprehensive set of variables. Selected variables were then entered into an ordinary least squares (OLS) model to compare coefficients and assess statistical significance.

RESULTS

Six negative predictors of university students' psychological wellbeing emerged: White/European ethnicity, restriction stress, perceived worry on mental health, dietary changes, perceived sufficiency of distancing communication, and social isolation. Physical health status, emotional support, and resilience were positively associated with students' psychological wellbeing. Social isolation has the largest effect on students' psychological wellbeing. Notably, age, gender, international status, and educational level did not emerge as predictors of wellbeing.

CONCLUSION

To cost-effectively support student wellbeing through 2021 and beyond, universities should consider investing in internet- and tele- based interventions explicitly targeting perceived social isolation among students. Course-based online forums as well as internet- and tele-based logotherapy may be promising candidates for improving students' psychological wellbeing.

Evaluating spatiotemporal dynamics of snakebite in Sri Lanka: Monthly incidence mapping from a national representative survey sample

BACKGROUND

Snakebite incidence shows both spatial and temporal variation. However, no study has evaluated spatiotemporal patterns of snakebites across a country or region in detail. We used a nationally representative population sample to evaluate spatiotemporal patterns of snakebite in Sri Lanka.

METHODOLOGY

We conducted a community-based cross-sectional survey representing all nine provinces of Sri Lanka. We interviewed 165 665 people (0.8% of the national population), and snakebite events reported by the respondents were recorded. Sri Lanka is an agricultural country; its central, southern and western parts receive rain mainly from Southwest monsoon (May to September) and northern and eastern parts receive rain mainly from Northeast monsoon (November to February). We developed spatiotemporal models using multivariate Poisson process modelling to explain monthly snakebite and envenoming incidences in the country. These models were developed at the provincial level to explain local spatiotemporal patterns.

PRINCIPAL FINDINGS

Snakebites and envenomings showed clear spatiotemporal patterns. Snakebite hotspots were found in North-Central, North-West, South-West and Eastern Sri Lanka. They exhibited biannual seasonal patterns except in South-Western inlands, which showed triannual seasonality. Envenoming hotspots were confined to North-Central, East and South-West parts of the country. Hotspots in North-Central regions showed triannual seasonal patterns and South-West regions had annual patterns. Hotspots remained persistent throughout the year in Eastern regions. The overall monthly snakebite and envenoming incidences in Sri Lanka were 39 (95%CI: 38-40) and 19 (95%CI: 13-30) per 100 000, respectively, translating into 110 000 (95%CI: 107 500-112 500) snakebites and 45 000 (95%CI: 32 000-73 000) envenomings in a calendar year.

CONCLUSIONS/SIGNIFICANCE

This study provides information on community-based monthly incidence of snakebites and envenomings over the whole country. Thus, it provides useful insights into healthcare decision-making, such as, prioritizing locations to establish specialized centres for snakebite management and allocating resources based on risk assessments which take into account both location and season.

Online interventions for people hospitalized for deliberate self-harm and problematic alcohol use: Lessons learned from the iiAIM trial

Deliberate self-harm and suicide affect all age groups, sexes, and regions, and their prevention is a global health priority. Acute alcohol misuse and chronic alcohol misuse are strong, modifiable risk factors, and Internet interventions aiming to reduce alcohol misuse and comorbid mental health problems (e.g., depression) are a promising and effective treatment modality. The research team aimed to evaluate the feasibility and effectiveness of an Internet-based comorbidity intervention primarily aiming to reduce alcohol consumption, and secondarily to reduce readmission for deliberate self-harm and improve psychological outcomes among people hospitalized for deliberate self-harm who also engage in problematic alcohol use. However, due to several barriers to recruitment, the trial could not be completed and was discontinued. The authors present a "Lessons Learned" discussion and describe the Internet Intervention for Alcohol Improvement (iiAIM) trial, discuss the key barriers experienced by the research team, and recommend potential solutions that may help future trials in this area.

841 The psychological impact of Foundation Interim Year 1 Placements on Final Year UK Medical Students Transitioning to Foundation Year One During the COVID Era

Introduction

During the COVID pandemic, the 2019-2020 cohort of final year students were invited to participate in Foundation interim Year 1 placements (FiY1). FiY1 aimed to ease transition to Foundation Year 1 doctor (FY1). We assessed the psychological impact of FiY1 on final year medical students.

Method

A cross-sectional survey was distributed to final year medical students in the UK between June 4th and July 4th, 2020. The survey contained the following domains: participant demographics, rationale for FiY1 participation, a checklist of the key safety principles for FiY1s, the Hospital Anxiety and Depression Scale and the Perceived Stress scale-4.

Results

107 final years responded to the survey. 72.0% (n = 77) of final year students surveyed were working as FiY1s. Final year students participating in FiY1 postings had reduced rates of anxiety (29.9% vs 43.4%, P = 0.186), depression (5.2% vs 20.0%, P = 0.018) and lower perceived stress levels (5.0 vs 7.2, P &lt; 0.001). 19.5% (15/77) FiY1s reported working beyond their competency, 27.3% (22/77) felt unsupervised, but 94.8% (73/77) of FiY1s felt the post prepared them for FY1.

Conclusions

Students participating in FiY1 postings felt less stressed and depressed than those not participating in the scheme and the majority felt it was preparing them for FY1.

After-Discharge in the Upper Airway Muscle Genioglossus Following Brief Hypoxia

STUDY OBJECTIVES

Genioglossus after-discharge is thought to protect against pharyngeal collapse by minimising periods of low upper airway muscle activity. How genioglossus after-discharge occurs and which single motor units (SMUs) are responsible for the phenomenon are unknown. The aim of this study was to investigate genioglossal after-discharge.

METHODS

During wakefulness, after-discharge was elicited 8-12 times in healthy individuals with brief isocapnic hypoxia (45-60s of 10%O2 in N2) terminated by a single breath of 100% O2. Genioglossus SMUs were designated as firing solely, or at increased rate, during inspiration (Inspiratory phasic [IP] and inspiratory tonic [IT] respectively); solely, or at increased rate, during expiration (Expiratory phasic [EP] or expiratory tonic [ET] respectively) or firing constantly without respiratory modulation (Tonic). SMUs were quantified at baseline, the end of hypoxia, the hyperoxic breath and the following 8 normoxic breaths.

RESULTS

210 SMU's were identified in 17 participants. Genioglossus muscle activity was elevated above baseline for 7 breaths after hyperoxia (p<0.001), indicating a strong after-discharge effect. After-discharge occurred due to persistent firing of IP and IT units that were recruited during hypoxia, with minimal changes in ET, EP or Tonic SMUs. The firing frequency of units that were already active changed minimally during hypoxia or the afterdischarge period (P>0.05).

CONCLUSION

That genioglossal after-discharge is almost entirely due to persistent firing of previously silent inspiratory SMUs provides insight into the mechanisms responsible for the phenomenon and supports the hypothesis that the inspiratory and expiratory/tonic motor units within the muscle have idiosyncratic functions.

Workplace Intimacy

Amidst massive economic damage tension between the needs to save lives and save jobs has become the basis of a key political fault-line and a matter of daily on-the-ground management during the COVID-19 pandemic. In this article we consider four especially salient changes to work-life wrought by the pandemic: (1) new workplace praxes pertaining to matters of touch; (2) erosion and degrading of the quality of erstwhile intimate relations in certain workplaces; (3) changes to senses of belonging and homeliness in workplaces; (4) and, reflecting on the particular type of work that we do, how the pandemic (and pandemic lockdown especially) is impacting our pedagogical and research practices. Throughout we reveal how the intimacies experienced within workplaces are being transformed – not always eroded or degraded, but also sometimes adapted, sustained in new ways (especially via new communications technologies), and even enhanced.

Aboriginal community controlled health organisations address health equity through action on the social determinants of health of Aboriginal and Torres Strait Islander peoples in Australia

BACKGROUND

Indigenous populations globally are continually striving for better health and wellbeing due to experiencing significant health and social inequities. The social determinants of health are important contributors to health outcomes. Comprehensive primary health care that is governed and delivered by Indigenous people extends beyond the biomedical model of care to address the social determinants of health. Aboriginal Community Controlled Health Organisations (ACCHOs) are known to provide culturally informed, holistic health services that directly and indirectly address the social determinants of health. The range and extent of their activities in addressing the social determinants of health, however, is not well documented.

METHODS

The most recent ACCHO annual reports were retrieved online or by direct correspondence. For coding consistency, a dictionary informed by the World Health Organization's Conceptual Framework for Action on the Social Determinants of Health was developed. A document and textual analysis of reports coded ACCHO activities and the determinants of health they addressed, including intermediary determinants, socio-economic position and/or socio-political context. Summary statistics were reported. Representative quotes illustrating the unique nature of ACCHO service provision in addressing the social determinants of health were used to contextualise the quantitative findings.

RESULTS

Sixty-seven annual reports were collected between 2017 and 2018. Programs were delivered to population groups across the life span. Fifty three percent of reports identified programs that included work at the socio-political level and all annual reports described working to improve socioeconomic position and intermediary determinants of health through their activities. Culture had a strong presence in program delivery and building social cohesion and social capital emerged as themes.

CONCLUSIONS

This study provides evidence of the considerable efforts of the ACCHO sector, as a primary health care provider, in addressing the social determinants of health and health inequity experienced by Indigenous communities. For the Aboriginal and Torres Strait Islander population, ACCHOs not only have an essential role in addressing immediate healthcare needs but also invest in driving change in the more entrenched structural determinants of health. These are important actions that are likely to have an accumulative positive effect in closing the gap towards health equity.

COVID-19 and the Transformation of Intimate Inter- and Intra-National Relations

Based conceptually on Michael Herzfeld’s ideas of cultural intimacy and disemia, and empirically on lockdown auto-ethnography, this article considers how erstwhile intimate inter-and intra-national relations have been transformed by COVID-19. Its particular ethnographic focus is Australian–British post-colonial relations and the personal emergence of a hybrid Br-Australian consciousness.

Social Intimacy

In this article, we highlight how COVID-19 has transformed, is transforming and may transform into the future human intimacies at several different social levels: between couples, within and between families, between citizens and states, among nations, and between people and their deities. We conclude by highlighting an uncertain future for intimacies that may entail the radical transformation of societies characterised by conversely new and liberating forms of socio-economic organisation or enslavement, especially to new spatio-temporal configurations engendered by the pandemic.

Understanding Stabilization in Nanoporous Intermetallic Alloy Anodes for Li-Ion Batteries Using Operando Transmission X-ray Microscopy

Tin-based alloying anodes are exciting due to their high energy density. Unfortunately, these materials pulverize after repetitive cycling due to the large volume expansion during lithiation and delithiation; both nanostructuring and intermetallic formation can help alleviate this structural damage. Here, these ideas are combined in nanoporous antimony-tin (NP-SbSn) powders, synthesized by a simple and scalable selective-etching method. The NP-SbSn exhibits bimodal porosity that facilitates electrolyte diffusion; those void spaces, combined with the presence of two metals that alloy with lithium at different potentials, further provide a buffer against volume change. This stabilizes the structure to give NP-SbSn good cycle life (595 mAh/g after 100 cycles with 93% capacity retention). Operando transmission X-ray microscopy (TXM) showed that during cycling NP-SbSn expands by only 60% in area and then contracts back nearly to its original size with no physical disintegration. The pores shrink during lithiation as the pore walls expand into the pore space and then relax back to their initial size during delithiation with almost no degradation. Importantly, the pores remained open even in the fully lithiated state, and structures are in good physical condition after the 36th cycle. The results of this work should thus be useful for designing nanoscale structures in alloying anodes.

The clinical toxicity of imidacloprid self-poisoning following the introduction of newer formulations

BACKGROUND

Self-poisoning with imidacloprid has been previously shown to have low toxicity in humans. Since 2007 newer formulations of Imidacloprid with unknown solvents have been introduced and the potential clinical consequences of these products have not been described.

METHODS

Clinical and demographic data were prospectively collected from admissions following oral ingestion of imidacloprid from seven hospitals in Sri Lanka. Data was collected from 2002 to 2007 in an already published study. We compared this data on poisonings collected from 2010 to 2016 following the introduction of new formulations of imidacloprid.

RESULTS

From 2002-2007, there were 56 patients with ingestion to imidacloprid compared to 67 patients post 2010 The median time to presentation prior to 2007 was 4 h (IQR 2.3-6.0 hrs) and post 2010 was only 2.0 hr (IQR 1.5 to 3.1 hrs). The median amount ingested was 15 ml (IQR 10.0-50.0mls) prior to 2007 and 27.5mls (IQR 5.0-71.8mls) post 2010. In both studies most patients developed non-specific symptoms including nausea, vomiting, epigastric pain and headache. However, prior to 2007 only 1.9% of the cohort required mechanical ventilation due to respiratory failure and there were no reported deaths. In contrast, post 2010; deaths occurred in 3.0% of the cohort and 6.0% required mechanical ventilation for respiratory failure. The cause of mortality was due to one case of cardiorespiratory failure and the other due to a prolonged admission complicated with lobar pneumonia leading to decompensated liver failure on the background of undiagnosed liver cirrhosis.

CONCLUSION

Although acute exposure to imidacloprid is usually associated with mild non-specific symptoms, since the introduction of new formulations of imidacloprid, the toxic profile has changed with reported cases of death as well as an increase in cases requiring mechanical ventilation. The change in toxicity could be due to the solvents used in the newer formulations but also due to higher dose of imidacloprid described in our latter cohort. Further research into these solvents needs to be done and continued toxicovigilance is required.

Foreign aid and the rule of law: Institutional diffusion versus legal reach

This paper examines the role of bilateral foreign aid in supporting the diffusion and enactment of common models and institutions of the rule of law among aid-recipient low- and middle-income countries. We ask whether aid targeted at security-sector reform and the rule of law influences the adoption of constitutional and legal reforms over time (institutional diffusion), and whether aid also supports more effective implementation of the rule of law, writ large (legal reach). We use event history and fixed-effects panel regression models to examine a sample of 154 countries between 1995 and 2013 to answer these questions. Our findings suggest that aid does increase the likelihood of adopting several rule of law reforms, but its effect on increasing the depth or quality of rule of law over time within countries is much less substantial. These findings suggest that though aid may play a role in supporting the diffusion of models contributing to state isomorphism among countries, it is less effective at increasing the pervasiveness and quality of such model's implementation. This discrepancy between the effectiveness of bilateral aid in promoting law on the books versus law in action in aid recipient countries calls into question the current approach to rule of law reforms.

Experiential Knowledge Affects the Visual Search Behaviors of Sprint Coaches and Sport Biomechanists

It is common for applied sport biomechanists and high-performance coaches to work closely together. A feature of this relationship is that both bring unique experiences and knowledge to the common goal of improving an athlete's performance. For sprint running, coaches and biomechanists place importance on different aspects of technique. The purpose of this paper was to determine if these differences in experiential knowledge impact coaches and biomechanists visual perception of sprinting technique. Sport biomechanists (n = 12) and, expert (n = 11) and developing (n = 11) coaches watched video of athletes sprinting at two different speeds while wearing eye tracking glasses and, retrospectively, reported on the technique features observed. Mixed methods ANOVAs were used to determine visual search strategies and efficiency and used to indicate the relationship between visual search and verbal commentary data. The speed of video playback was the main determinant of visual search behavior, significantly impacting the visual search rate and relative fixation duration at a number of areas of interest. The use of a visual pivot indicated all participants' visual search strategies were efficiency driven. Overall, the verbal commentary did not completely align with the eye tracking data and there were varying degrees of agreement with the identified technique related areas of interest for coaches and biomechanists. However, differences in visual search strategy and verbal commentary suggest that experiential knowledge impacts participants' observation and perception of sprinting technique.

Microbial Intimacy

In this article, we highlight how COVID-19 has transformed, is transforming and may transform into the future human intimacies. This, we argue, is an appropriate focus for anthropological investigation particularly. We posit a scaler approach to the anthropological study of the transformation of intimacy in COVID-19, embracing multiple levels from human relations with microbes through to human relations with deities. Furthermore, we offer examples of the overlaps between the ways in which intimate relationships at small and large scales are conceptualised, especially metaphorically.

Toxicological analysis of serious drug-related harm among electronic dance music festival attendees in New South Wales, Australia: A consecutive case series

BACKGROUND

A substantial increase in drug-related harm was observed during the 2018-2019 music festival season in New South Wales, Australia, including the deaths of five young people. As part of a rapid public health response, the New South Wales Ministry of Health referred samples from patients with suspected severe drug-related illness for forensic toxicological testing to identify the type and concentration of substances associated with the presentations.

METHODS

Cases were identified through a variety of active and passive surveillance systems, and selected consecutively based on indicators of clinical severity. Comprehensive toxicology testing of blood and urine samples was expedited for all cases. Demographic and clinical characteristics were collated, together with quantitative toxicology results. Results were analysed using descriptive statistics.

RESULTS

Forty cases from eleven different music festivals were included. The majority of cases (80.0%) were aged 25 years and under. There were five fatalities, and 62.5% of cases were admitted to intensive care units. MDMA was the most frequent substance, detected in 87.5% of cases. In 82.9% of cases with MDMA, blood concentrations were above thresholds that have been associated with toxicity. Multiple substances were detected in 60.0% of cases. Novel psychoactive substances were not detected.

CONCLUSIONS

Our findings strongly suggest that MDMA-related toxicity was a major factor in the severity of the clinical presentations among these cases. Other substances may have enhanced MDMA toxicity but appear unlikely to have caused severe toxicity in isolation. These findings have important implications for harm reduction strategies targeted to music festival settings.

Does Nasal Obstruction Induce Obstructive Sleep Apnea in Healthy Women?

PURPOSE

Obstructive sleep apnea (OSA) is less prevalent among women and is associated with different symptoms and consequences to OSA in men. The reasons for these differences are unknown and difficult to tease apart in clinical populations. If OSA could be temporarily induced in healthy men and women, the causes of some of these differences could be investigated. Nasal blocking has been used to induce OSA in healthy men but its effect in women has not been reported.

PATIENTS AND METHODS

A total of 14 healthy individuals (10 women) underwent in-laboratory diagnostic sleep studies on two occasions separated by a week. On one occasion, the nasal passages were blocked, whereas on the other occasion, participants slept naturally. In both conditions, a full-face mask was used to monitor respiratory events. Participants' self-reported sleepiness, mood and performance on a motor learning task were assessed in the evening and morning of both sleep studies. Furthermore, endothelial function and self-reported sleep quality were assessed in the morning following each study.

RESULTS

Nasal blockage induced OSA in healthy young (age=22±3 years) and slim (BMI=22.2±3.2 kg/m²) women (control AHI=2.0±2.6, blocked AHI=33.1±36.7 events/hr, p=0.02). One night of OSA was associated with poorer self-reported sleep quality (p<0.001) and increased self-reported snoring (p<0.04), choking and gasping during sleep (p<0.001) but was not associated with alterations in mood, neurocognitive or endothelial function on the following morning.

CONCLUSION

Nasal blockage induces OSA in healthy, young, and normal weight women. However, whether the induced OSA is representative of naturally occurring OSA and the technique useful for future studies is unclear.