Evaluation of the population-level impacts of the LiveLighter® obesity prevention campaign from 2012 to 2019 based on serial cross-sectional surveys

BACKGROUND

Halting and reversing the upward trend in obesity requires sustained implementation of comprehensive, evidence-based strategies at the population-level. The LiveLighter® program targets adults using a range of public education strategies, including mass media campaigns, to support healthy lifestyle changes to attain or maintain a healthy weight and reduce the risk of chronic disease. LiveLighter® has been implemented in Western Australia (WA) since 2012 and, to our knowledge, includes the longest running adult-targeted mass media campaign for healthy weight and lifestyle promotion and education globally. This evaluation assessed the impact of LiveLighter® on WA adults' knowledge, intentions and behaviours as they relate to healthy eating and body weight from 2012 to 2019.

METHODS

LiveLighter® mass media campaigns, which are TV-led and aired statewide, depict genuine, graphic imagery of visceral fat around internal organs to raise awareness about the link between excess body weight and chronic diseases; demonstrate how unhealthy food and drink consumption can contribute to unhealthy weight gain; and recommend healthy alternatives. Cross-sectional telephone surveys were conducted at baseline and following each campaign phase with an independent, randomly selected sample of WA adults aged 25 to 49 years (n = 501 to n = 1504 per survey) to assess their knowledge of the link between excess body weight and chronic diseases, and their intentions and behaviours related to healthy eating and weight. Multivariable logistic regression models were undertaken to assess differences in responses between baseline and each post-campaign survey.

RESULTS

Compared to baseline, there were significant increases in the proportion of respondents reporting knowledge of excess body weight as a risk factor for certain cancers and type 2 diabetes, intentions to eat more fruit and vegetables and drink less sugar sweetened beverages (SSBs) in the next seven days, and the proportion of respondents who reported meeting guidelines for daily vegetable intake. Reported consumption of SSBs significantly decreased.

CONCLUSIONS

LiveLighter® is associated with improvements in knowledge of the health risks associated with excess body mass, increased vegetable intake and reduced SSB consumption in WA adults. These findings support the use of sustained, well-designed healthy lifestyle promotion and education programs as part of a comprehensive obesity prevention strategy.

Stiffness Mediated-Mechanosensation of Airway Smooth Muscle Cells on Linear Stiffness Gradient Hydrogels

In obstructive airway diseases such as asthma and chronic obstructive pulmonary disease (COPD), the extracellular matrix (ECM) protein amount and composition of the airway smooth muscle (ASM) is often remodelled, likely altering tissue stiffness. The underlying mechanism of how human ASM cell (hASMC) mechanosenses the aberrant microenvironment is not well understood. Physiological stiffnesses of the ASM were measured by uniaxial compression tester using porcine ASM layers under 0, 5 and 10% longitudinal stretch above in situ length. Linear stiffness gradient hydrogels (230 kPa range) were fabricated and functionalized with ECM proteins, collagen I (ColI), fibronectin (Fn) and laminin (Ln), to recapitulate the above-measured range of stiffnesses. Overall, hASMC mechanosensation exhibited a clear correlation with the underlying hydrogel stiffness. Cell size, nuclear size and contractile marker alpha-smooth muscle actin (αSMA) expression showed a strong correlation to substrate stiffness. Mechanosensation, assessed by Lamin-A intensity and nuc/cyto YAP, exhibited stiffness-mediated behaviour only on ColI and Fn-coated hydrogels. Inhibition studies using blebbistatin or Y27632 attenuated most mechanotransduction-derived cell morphological responses, αSMA and Lamin-A expression and nuc/cyto YAP (blebbistatin only). This study highlights the interplay and complexities between stiffness and ECM protein type on hASMC mechanosensation, relevant to airway remodelling in obstructive airway diseases.

Process evaluation of a maintenance pulmonary rehabilitation trial for people with chronic obstructive pulmonary disease

BACKGROUND

The ComEx3 community-based extended maintenance pulmonary rehabilitation (PR) randomised controlled trial (RCT) aimed to determine the optimal strategy for maintaining the benefits of exercise for people with chronic obstructive pulmonary disease (COPD). We conducted a process evaluation of this RCT to determine if the trial was implemented per protocol, and to explore the barriers and facilitators of the trial, and mechanisms of impact.

METHODS

This was a mixed methods study consisting of analysis of PR class records, study diaries and interviews of those involved in the trial. We developed a reporting framework from available literature and performed a content analysis.

RESULTS

Eleven of the 12 participants in the intervention group attended ≥70% of available classes before the trial was terminated due to the COVID-19 pandemic. Analysis of the study diaries found that adherence to the home exercise program was higher in the intervention than the control group. Analyses of interviews (n = 21) highlighted the complexity of standardising the processes across multiple sites, but revealed behaviour change amongst class physiotherapists who were able to conform with the required processes. Facilitators of participation included the desire to improve function and quality of life, while barriers included illnesses and lack of motivation. Mechanisms of impact included confidence in exercising and benefits from the education sessions.

CONCLUSIONS

The ComEx3 RCT was implemented as planned largely due to commitment by the research team and the desire by patients to improve their quality of life by attending a PR program that they are familiar with. Successful implementation of PR RCTs requires good organisational skills, clear and consistent trial documentation, broad understanding of participant needs while being conscious of challenges experienced by people with COPD, and dedication by everyone involved in the RCT. SO WHAT?: This article shows the importance of running a process evaluation alongside an RCT. Although this RCT did not progress to completion, this process evaluation which was guided by a robust framework, will provide guidance for future interventions in this area.

Patient evaluation of gynaecological information provision and preferences

AIM

To evaluate gynaecological patients' preferences and satisfaction regarding information provision, exploring enablers and barriers to information access.

DESIGN

A descriptive cross-sectional survey design was used.

METHODS

A total of 293 women accessing gynaecological services responded to the survey. Quantitative analysis included descriptive and inferential statistics. Content analysis was conducted on qualitative data.

RESULTS

Health professionals were the most common and preferred sources of gynaecological health information. Enablers to information provision included positive communication strategies by health professionals, participants having prior knowledge and doing their own research. Despite its widespread availability, only 24.2% of women preferred the internet as an information source. Poor communication and inadequate information provision were identified as barriers to information access. Statistically significant associations were identified between location of residence, education level, year of birth, diagnostic group and health information preferences. Recommendations from women included improved communication strategies, system changes and provision of individualized information.

CONCLUSION

Health professionals are central to women accessing information about gynaecological diagnoses. Areas for improvement include communication strategies, facilitating access to internet-based resources for information and consideration of women's preferences when providing health information.

IMPLICATIONS FOR THE PROFESSION AND PATIENT CARE

Consumer co-design of gynaecological health information and communication training for health professionals is recommended. Improved communication and facilitated use of internet-based resources may improve women's understanding of information.

IMPACT

This study explored gynaecological patients' preferences and satisfaction regarding information provision, exploring enablers and barriers to information access. It was found that gynaecological patients preferred individualized information provided to them directly by health professionals and despite its widespread availability, the internet is an underutilized health information resource. These findings are applicable to health professionals and patients utilizing tertiary gynaecological health services in Australia but may be generalized if demographic data aligns with other jurisdictions.

REPORTING METHOD

The STROBE reporting method was used in the preparation of the manuscript.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Quantifying uptake and completion of pulmonary rehabilitation programs in people with chronic obstructive pulmonary disease known to tertiary care

BACKGROUND

People with symptomatic chronic obstructive pulmonary disease (COPD) benefit from pulmonary rehabilitation programs (PRPs), but program attrition is common.

METHODS

For people with COPD who presented to tertiary care and appeared appropriate for a PRP, we prospectively mapped their PRP journey, explored factors influencing attendance to pre-program assessment and captured program attrition.

RESULTS

Of the 391 participants, 31% (95% CI 27 to 36) were referred to a PRP (n = 123; age 68 ± 10years, 62 males [50%], FEV1 45 ± 19%predicted). Of those referred, 94 (76% [69 to 84]) attended a pre-program assessment. Ex-smokers and those who had a healthcare professional (HCP) explain they would be referred were more likely to attend a pre-program assessment (odds ratio [95%CI]; 2.6 [1.1 to 6.1]; and 4.7 [1.9 to 11.7], respectively). Of the 94 who attended, 63 (67% [58 to 77]) commenced; and of those who commenced, 35 (56% [43 to 68]) completed a PRP. All who completed (n = 35, 100%) were provided at least one strategy to maintain training-related gains.

CONCLUSION

Attrition occurs throughout the PRP journey. Interactions with HCPs about PRPs positively influenced attendance. Understanding how HCPs can best contextualise PRPs to encourage referral acceptance and uptake is an important area for further work.

Gene editing and cardiac disease modelling for the interpretation of genetic variants of uncertain significance in congenital heart disease

BACKGROUND

Genomic sequencing in congenital heart disease (CHD) patients often discovers novel genetic variants, which are classified as variants of uncertain significance (VUS). Functional analysis of each VUS is required in specialised laboratories, to determine whether the VUS is disease causative or not, leading to lengthy diagnostic delays. We investigated stem cell cardiac disease modelling and transcriptomics for the purpose of genetic variant classification using a GATA4 (p.Arg283Cys) VUS in a patient with CHD.

METHODS

We performed high efficiency CRISPR gene editing with homology directed repair in induced pluripotent stem cells (iPSCs), followed by rapid clonal selection with amplicon sequencing. Genetic variant and healthy matched control cells were compared using cardiomyocyte disease modelling and transcriptomics.

RESULTS

Genetic variant and healthy cardiomyocytes similarly expressed Troponin T (cTNNT), and GATA4. Transcriptomics analysis of cardiomyocyte differentiation identified changes consistent with the patient's clinical human phenotype ontology terms. Further, transcriptomics revealed changes in calcium signalling, and cardiomyocyte adrenergic signalling in the variant cells. Functional testing demonstrated, altered action potentials in GATA4 genetic variant cardiomyocytes were consistent with patient cardiac abnormalities.

CONCLUSIONS

This work provides in vivo functional studies supportive of a damaging effect on the gene or gene product. Furthermore, we demonstrate the utility of iPSCs, CRISPR gene editing and cardiac disease modelling for genetic variant interpretation. The method can readily be applied to other genetic variants in GATA4 or other genes in cardiac disease, providing a centralised assessment pathway for patient genetic variant interpretation.

Age-dependent genetic regulation of osteoarthritis: independent effects of immune system genes

OBJECTIVES

Osteoarthritis (OA) is a joint disease with a heritable component. Genetic loci identified via genome-wide association studies (GWAS) account for an estimated 26.3% of the disease trait variance in humans. Currently, there is no method for predicting the onset or progression of OA. We describe the first use of the Collaborative Cross (CC), a powerful genetic resource, to investigate knee OA in mice, with follow-up targeted multi-omics analysis of homologous regions of the human genome.

METHODS

We histologically screened 275 mice for knee OA and conducted quantitative trait locus (QTL) mapping in the complete cohort (> 8 months) and the younger onset sub-cohort (8-12 months). Multi-omic analysis of human genetic datasets was conducted to investigate significant loci.

RESULTS

We observed a range of OA phenotypes. QTL mapping identified a genome-wide significant locus on mouse chromosome 19 containing Glis3, the human equivalent of which has been identified as associated with OA in recent GWAS. Mapping the younger onset sub-cohort identified a genome-wide significant locus on chromosome 17. Multi-omic analysis of the homologous region of the human genome (6p21.32) indicated the presence of pleiotropic effects on the expression of the HLA - DPB2 gene and knee OA development risk, potentially mediated through the effects on DNA methylation.

CONCLUSIONS

The significant associations at the 6p21.32 locus in human datasets highlight the value of the CC model of spontaneous OA that we have developed and lend support for an immune role in the disease. Our results in mice also add to the accumulating evidence of a role for Glis3 in OA.

Developing an Australian utility value set for the Early Childhood Oral Health Impact Scale-4D (ECOHIS-4D) using a discrete choice experiment

PURPOSE

Preference-based quality of life measures (PBMs) are used to generate quality-adjusted life years (QALYs) in economic evaluations. A PBM consists of (1) a health state classification system and (2) a utility value set that allows the instrument responses to be converted to QALYs. A new, oral health-specific classification system, the Early Childhood Oral Health Impact Scale-4D (ECOHIS-4D) has recently been developed. The aim of this study was to generate an Australian utility value set for the ECOHIS-4D.

METHODS

A discrete choice experiment with duration (DCETTO) was used as the preference elicitation technique. An online survey was administered to a representative sample of Australian adults over 18 years. Respondents were given 14 choice tasks (10 tasks from the DCE design of 50 choice sets blocked into five blocks, 2 practice tasks, a repeated and a dominant task). Data were analyzed using the conditional logit model.

RESULTS

A total of 1201 respondents from the Australian general population completed the survey. Of them, 69% (n = 829) perceived their oral health status to be good, very good, or excellent. The estimated coefficients from the conditional logit models were in the expected directions and were statistically significant (p < 0.001). The utility values for health states defined by the ECOHIS-4D ranged from 0.0376 to 1.0000.

CONCLUSIONS

This newly developed utility value set will enable the calculation of utility values for economic evaluations of interventions related to oral diseases such as dental caries among young children. This will facilitate more effective resource allocation for oral health services.

Public support for obesity prevention policies in Western Australia from 2012 to 2020: Findings from cross-sectional surveys

ISSUE ADDRESSED

This study explored trends in public support for obesity prevention policies in Western Australia (WA).

METHODS

A series of cross-sectional surveys of a representative sample of WA adults aged 25-49 years (N = 11 534) were undertaken between 2012 and 2020 as part of an evaluation of the LiveLighter® mass media campaign, a component of a statewide healthy lifestyle education and promotion programme. Computer-assisted telephone interviews were used to gauge support for a range of obesity prevention initiatives that could be implemented by government.

RESULTS

A majority of respondents supported a range of obesity prevention policies, including taxes on sugary drinks, urban planning regulations, food labelling and packaging regulations, restrictions on advertising and sponsorship, bans on the sale and marketing of unhealthy food and drink in retail environments and support for education and campaigns. Obesity prevention policies were highly supported by women, people with a healthy weight, and those who had completed secondary school. Support for regulation was high compared to other studies. Notably, there were significant increases in support between baseline and 2020 for 'taxing soft drinks and using the money to reduce the cost of healthy food' (72% cf. 80%) and 'restricting junk food promotions/advertisements on public transport' (73% cf. 83%).

CONCLUSIONS

There is substantial public support for regulatory action on obesity prevention in WA, providing strong rationale for government interventions to improve nutrition and reduce obesity. The LiveLighter® programme may have contributed to increases in support for obesity prevention policies in WA. SO WHAT?: There is potential to implement robust obesity prevention policies in WA.

Requesting HIV Results Be Conveyed in-Person: Perspectives of Clinicians and People Recently Diagnosed with HIV

Introduction

Guidelines recommend that, where possible, clinicians convey HIV-positive test results in person in Australia. However, HIV-negative and all other STI results are routinely delivered by phone or text message. Requesting individuals to obtain positive HIV test results in person could be a deviation from the standard delivery of healthcare and be interpreted as indicating a positive HIV diagnosis.

Methods

This paper is based on two related, ongoing qualitative studies conducted in Australia with HIV healthcare providers and people recently diagnosed with HIV. In study one, in-depth, semi-structured interviews were conducted with people who had recently received a positive HIV diagnosis. In study two, in-depth, semi-structured interviews were conducted with HIV healthcare and peer support providers. Interviews were analyzed thematically.

Results

While clinicians were willing to convey HIV-positive diagnoses by phone, most preferred in-person delivery. In-person delivery enabled clinicians to assess visual cues to better respond to the psychological and emotional needs of patients. For some participants living with HIV, however, the requirement to return to the clinic was interpreted as an unofficial HIV-positive diagnosis. This led to a period in which recently diagnosed participants believed they were HIV-positive without having received an explicit diagnosis.

Conclusion

Protocols for delivering HIV diagnoses by phone, followed by a face-to-face appointment, may reduce the period of anxiety for some patients and assist with an early connection to HIV care and support.

Policy Implications

In some instances, conveying HIV diagnoses by phone may be more appropriate than recalling individuals to the clinic to deliver a positive HIV diagnosis in person.

The feasibility of a digital health approach to facilitate remote dental screening among preschool children during COVID-19 and social restrictions

BACKGROUND

Tele-dentistry can be useful to facilitate screening of children, especially those living in rural and remote communities, and during the COVID-19 pandemic.

AIM

This study evaluated the feasibility of tele-dental screening for the identification of early childhood caries (ECC) in preschoolers using an app operated by their parents with remote review by oral-health therapists.

DESIGN

This cross-sectional study was a sub-project nested in ORIGINS Project, a longitudinal birth cohort study in Western Australia. Initially, children were visually examined by a paediatric dentist (gold standard). Subsequently, dental photographs were taken by parents using a smartphone camera. Two trained oral health professionals asynchronously evaluated dental photographs. The presence of dental caries was recorded as per the International Caries Detection and Assessment System-II classification. The diagnostic accuracy and reliability of the tele-dental screening and the gold standard dental examinations were then compared.

RESULTS

Forty-two children aged <4 years were enrolled in the study. Twenty-five per cent of examined children had dental caries (mean dmfs = 0.7). A total of 370 dental photographs were obtained. Parents were able to take good-quality photographs, with 90% of photographs rated as good to fair quality. Tele-dental screening demonstrated high specificity (>=95.5%) for both reviewers compared to the gold standard dental examination. However, the sensitivity scores for the two reviewers varied, ranging from 44% to 88.4%.

CONCLUSION

Tele-dental screening for ECC was shown to be a feasible approach following a brief training for primary caregivers. This approach can offer a potential low-cost and sustainable alternative for visual dental examinations for young children, particularly in times of COVID-19-related restrictions.

Opioid poisoning during pregnancy: prevalence, characteristics, and neonatal outcomes

While it has been postulated that opioid poisoning during pregnancy may cause adverse maternal and neonatal outcomes, the harm associated with opioid poisoning during pregnancy has not been robustly examined. Pregnant women admitted to hospital or presenting to the emergency department (ED) in Western Australia (WA) with a diagnosis of opioid poisoning were identified by linking state midwifery records with hospital and ED administrative data. Maternal and neonatal outcomes were compared with opioid poisoning that occurred in the 12 months prior to conception or the 12 months following birth. Between 2003 and 2018, 57 neonates were born to women who had experienced opioid poisoning during pregnancy (14.1 per 100,000 births) in WA. The incidence of opioid poisoning in the year prior to pregnancy (IRR: 3.04, 95%CI: 2.30, 4.02) and the year following pregnancy (IRR: 1.96, 95%CI: 1.46, 2.64) was significantly higher than during pregnancy. Opioid poisoning during pregnancy was less likely to involve multiple substances and be intentional (rather than accidental). Neonatal conditions associated with in utero hypoxia were significantly less common in neonates born to women who experience opioid poisoning prior to pregnancy compared with during pregnancy (OR: 0.17, 95%CI: 0.04, 0.80). Opioid poisoning in pregnancy was not associated with an increased risk of other serious adverse neonatal outcomes. Opioid poisoning during pregnancy is uncommon and less likely to be intentional and involve multiple substances. Opioid poisoning during pregnancy is likely associated with an increased risk of conditions associated with in utero hypoxia.

Changing Levels of Social Engagement with Gay Men Is Associated with HIV Related Outcomes and Behaviors: Trends in Australian Behavioral Surveillance 1998-2020

Changes to how gay, bisexual, and other men who have sex with men (GBM) connect with each other and with their communities have implications for HIV prevention. Social engagement with gay men (defined as having friends who are gay men and spending time with them) has been associated with HIV related outcomes over time among Australian GBM. Using data collected in national, repeated, cross-sectional surveys of GBM between 1998 and 2020 (N = 161,117), analyses of trends in the prevalence of gay social engagement (GSE) in Australia were conducted using linear regression. To assess changing associations with GSE at different time points in the HIV epidemic, three cross-sectional analyses were conducted on factors associated with high and low GSE in 1999/2000, 2009/2010, and 2019/2020 using bivariate and multivariable logistic regression. GSE (scored from 0 to 7) declined among all participants from 4.76 in 1998 to 4.04 in 2020 (p < 0.001) with a steeper decline among GBM aged under 25 years from 4.63 in 1998 to 3.40 in 2020 (p < 0.001). In all timepoints, high GSE was associated with older age, being university educated, full time employment, identifying as gay, recent HIV testing, and PrEP uptake. While mostly associated with protective behaviors, high GSE was also associated with some practices that may put GBM at risk of HIV infection such as drug-enhanced sex and group sex in the most recent timepoint. Changing levels of GSE have implications for health promotion among GBM, particularly how to engage GBM less connected to gay social networks.

Implementation of a strategy to facilitate effective medical follow-up for Australian First Nations children hospitalised with lower respiratory tract infections: study protocol

BACKGROUND

First Nations children hospitalised with acute lower respiratory infections (ALRIs) are at increased risk of future bronchiectasis (up to 15-19%) within 24-months post-hospitalisation. An identified predictive factor is persistent wet cough a month after hospitalisation and this is likely related to protracted bacterial bronchitis which can progress to bronchiectasis, if untreated. Thus, screening for, and optimally managing, persistent wet cough one-month post-hospitalisation potentially prevents bronchiectasis in First Nations' children. Our study aims to improve the post-hospitalisation medical follow-up for First Nations children hospitalised with ALRIs and thus lead to improved respiratory health. We hypothesize that implementation of a strategy, conducted in a culturally secure manner, that is informed by barriers and facilitators identified by both parents and health care providers, will improve medical follow-up and management of First Nations children hospitalized with ALRIs.

METHODS

Our trial is a multi-centre, pseudo-randomized stepped wedge design where the implementation of the strategy is tailored for each study site through a combined Participatory Action Research and implementation science approach informed by the Consolidated Framework of Implementation Research. Outcome measures will consist of three categories related to (i) health, (ii) economics and (iii) implementation. The primary outcome measure will be Cough-specific Quality of Life (PC-QoL). Outcomes will be measures at each study site/cluster in three different stages i.e., (i) nil-intervention control group, (ii) health information only control group and (iii) post-intervention group.

DISCUSSION

If our hypothesis is correct, our study findings will translate to improved health outcomes (cough related quality of life) in children who have persistent wet cough a month after hospitalization for an ALRI. Trial registration ACTRN12622000224729, prospectively registered 8 February 2022, URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382886&isReview=true .

Does a high dietary intake of resistant starch affect glycaemic control and alter the gut microbiome in women with gestational diabetes? A randomised control trial protocol

BACKGROUND

Gestational Diabetes Mellitus (GDM) is prevalent with lasting health implications for the mother and offspring. Medical nutrition therapy is the foundation of GDM management yet achieving optimal glycaemic control often requires treatment with medications, like insulin. New dietary strategies to improve GDM management and outcomes are required. Gut dysbiosis is a feature of GDM pregnancies, therefore, dietary manipulation of the gut microbiota may offer a new avenue for management. Resistant starch is a fermentable dietary fibre known to alter the gut microbiota and enhance production of short-chain fatty acids. Evidence suggests that short-chain fatty acids improve glycaemia via multiple mechanisms, however, this has not been evaluated in GDM.

METHODS

An open-label, parallel-group design study will investigate whether a high dietary resistant starch intake or resistant starch supplement improves glycaemic control and changes the gut microbiome compared with standard dietary advice in women with newly diagnosed GDM. Ninety women will be randomised to one of three groups - standard dietary treatment for GDM (Control), a high resistant starch diet or a high resistant starch diet plus a 16 g resistant starch supplement. Measurements taken at Baseline (24 to 30-weeks' gestation), Day 10 and Day 56 (approximately 36 weeks' gestation) will include fasting plasma glucose levels, microbial composition and short-chain fatty acid concentrations in stool, 3-day dietary intake records and bowel symptoms questionnaires. One-week post-natal data collection will include microbial composition and short-chain fatty acid concentrations of maternal and neonatal stools, microbial composition of breastmilk, birthweight, maternal and neonatal outcomes. Mixed model analysis of variance will assess change in glycaemia and permutation-based multivariate analysis of variance will assess changes in microbial composition within and between intervention groups. Distance-based linear modelling will identify correlation between change in stool microbiota, short-chain fatty acids and measures of glycaemia.

DISCUSSION

To improve outcomes for GDM dyads, evaluation of a high dietary intake of resistant starch to improve glycaemia through the gut microbiome needs to be established. This will expand the dietary interventions available to manage GDM without medication.

TRIAL REGISTRATION

Australian New Zealand Clinical Trial Registry, ACTRN12620000968976p . Registered 28 September 2020.

Molecular, Cellular and Functional Changes in the Retinas of Young Adult Mice Lacking the Voltage-Gated K+ Channel Subunits Kv8.2 and K2.1

Cone Dystrophy with Supernormal Rod Response (CDSRR) is a rare autosomal recessive disorder leading to severe visual impairment in humans, but little is known about its unique pathophysiology. We have previously shown that CDSRR is caused by mutations in the KCNV2 (Potassium Voltage-Gated Channel Modifier Subfamily V Member 2) gene encoding the Kv8.2 subunit, a modulatory subunit of voltage-gated potassium (Kv) channels. In a recent study, we validated a novel mouse model of Kv8.2 deficiency at a late stage of the disease and showed that it replicates the human electroretinogram (ERG) phenotype. In this current study, we focused our investigation on young adult retinas to look for early markers of disease and evaluate their effect on retinal morphology, electrophysiology and immune response in both the Kv8.2 knockout (KO) mouse and in the Kv2.1 KO mouse, the obligate partner of Kv8.2 in functional retinal Kv channels. By evaluating the severity of retinal dystrophy in these KO models, we demonstrated that retinas of Kv KO mice have significantly higher apoptotic cells, a thinner outer nuclear cell layer and increased activated microglia cells in the subretinal space. Our results indicate that in the murine retina, the loss of Kv8.2 subunits contributes to early cellular and physiological changes leading to retinal dysfunction. These results could have potential implications in the early management of CDSRR despite its relatively nonprogressive nature in humans.

Blood-brain barrier disruption and ventricular enlargement are the earliest neuropathological changes in rats with repeated sub-concussive impacts over 2 weeks

Repeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood-brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.

Stopping targeted therapy for complete responders in advanced BRAF mutant melanoma

BRAF inhibitors revolutionised the management of melanoma patients and although resistance occurs, there is a subgroup of patients who maintain durable disease control. For those cases with durable complete response (CR) it is not clear whether it is safe to cease therapy. Here we identified 13 patients treated with BRAF +/- MEK inhibitors, who cease therapy after prolonged CR (median = 34 months, range 20-74). Recurrence was observed in 3/13 (23%) patients. In the remaining 10 patients with sustained CR off therapy, the median follow up after discontinuation was 19 months (range 8-36). We retrospectively measured ctDNA levels using droplet digital PCR (ddPCR) in longitudinal plasma samples. CtDNA levels were undetectable in 11/13 cases after cessation and remained undetectable in patients in CR (10/13). CtDNA eventually became detectable in 2/3 cases with disease recurrence, but remained undetectable in 1 patient with brain only progression. Our study suggests that consideration could be given to ceasing targeted therapy in the context of prolonged treatment, durable response and no evidence of residual disease as measured by ctDNA.

OPTImising the implementation of pulMonary rehAbiLitation in people with chronic obstructive pulmonary disease (the OPTIMAL study): mixed methods study protocol

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common respiratory condition characterised by dyspnoea during daily life. As the disease progresses, people with COPD can experience poor quality of life, reduced exercise capacity, worsening of symptoms and increased hospital admissions. Pulmonary rehabilitation, which includes exercise training, optimises both psychological and physical function, reduces symptoms and mitigates healthcare utilisation in people with COPD. There is, however, a gap in implementation of pulmonary rehabilitation programs, with global access limited to a small fraction of people with COPD. The overall aim of this study is to gather evidence that will optimise the implementation of pulmonary rehabilitation in people with COPD living in Perth, Western Australia.

METHODS

This is a mixed methods study protocol informed by a critical realist perspective. The study will comprise four phases. In Phase 1, we will quantify target behaviours of healthcare professionals and people with COPD which are related to the implementation of pulmonary rehabilitation at three tertiary hospitals. In Phase 2, we will conduct semi-structured interviews to explore the determinants of these target behaviours from the perspectives of healthcare professionals, people with COPD and their primary support person. In Phase 3, knowledge gained in Phases 1 and 2 will be used by healthcare professionals and people with COPD to co-create, field test and apply strategies that optimise these target behaviours. In Phase 4, we will re-quantify these target behaviours to determine the influence of co-created strategies. The cost effectiveness of implementing the co-created strategies will be explored by an economic analysis.

DISCUSSION

Understanding current clinical practice and the determinants of target behaviours pertaining to the implementation of pulmonary rehabilitation is crucial when developing strategies that successfully bridge the pulmonary rehabilitation implementation gap. If co-created strategies are effective, more people with COPD living in Perth, Western Australia will have access to pulmonary rehabilitation enabling them to derive the health benefits associated with this intervention.

Association Between Characteristics of Injurious Falls and Fall Preventive Interventions in Acute Medical and Surgical Units

BACKGROUND

Hospital falls remain common and approximately 30% of falls in hospital result in injury. The aims of the study were the following: (i) to identify the association between fall interventions present at the time of the injurious fall and injurious faller characteristics and (ii) to identify the association between fall preventive interventions present at the time of the injurious fall and the injurious fall circumstances.

METHODS

Secondary data analysis of deidentified case series of injurious falls across 24 acute medical/surgical units in the United States. Variables of interest were falls prevention interventions (physical therapy, bed alarm, physical restraint, room change, or a sitter) in place at the time of fall. Data were analyzed using logistic regression and hazard ratios.

RESULTS

There were 1,033 patients with an injurious fall, occurrence peaked between Day 1 and Day 4, with 46.8% of injurious falls having occurred by Day 3 of admission. Injurious fallers with a recorded mental state change 24 hours prior to the fall were more likely to have a bed alarm provided (adjusted odds ratio [OR] 2.56, 95% confidence interval [CI] 1.61, 4.08) and receive a physical restraint as fall prevention interventions (adjusted OR 6.36, 95% CI 4.35, 9.30). Injurious fallers restrained fell later (stay Day 6) than those without a restraint (stay Day 4) (p = .007) and had significantly longer lengths of stay (13 days vs 9 days).

CONCLUSIONS

On medical/surgical units, injurious falls occur early following admission suggesting interventions should be commenced immediately. Injurious fallers who had a physical restraint as an intervention had longer lengths of stay.

A Multicenter Trial of Vena Cava Filters in Severely Injured Patients

BACKGROUND

Whether early placement of an inferior vena cava filter reduces the risk of pulmonary embolism or death in severely injured patients who have a contraindication to prophylactic anticoagulation is not known.

METHODS

In this multicenter, randomized, controlled trial, we assigned 240 severely injured patients (Injury Severity Score >15 [scores range from 0 to 75, with higher scores indicating more severe injury]) who had a contraindication to anticoagulant agents to have a vena cava filter placed within the first 72 hours after admission for the injury or to have no filter placed. The primary end point was a composite of symptomatic pulmonary embolism or death from any cause at 90 days after enrollment; a secondary end point was symptomatic pulmonary embolism between day 8 and day 90 in the subgroup of patients who survived at least 7 days and did not receive prophylactic anticoagulation within 7 days after injury. All patients underwent ultrasonography of the legs at 2 weeks; patients also underwent mandatory computed tomographic pulmonary angiography when prespecified criteria were met.

RESULTS

The median age of the patients was 39 years, and the median Injury Severity Score was 27. Early placement of a vena cava filter did not result in a significantly lower incidence of symptomatic pulmonary embolism or death than no placement of a filter (13.9% in the vena cava filter group and 14.4% in the control group; hazard ratio, 0.99; 95% confidence interval [CI], 0.51 to 1.94; P = 0.98). Among the 46 patients in the vena cava filter group and the 34 patients in the control group who did not receive prophylactic anticoagulation within 7 days after injury, pulmonary embolism developed in none of those in the vena cava filter group and in 5 (14.7%) in the control group, including 1 patient who died (relative risk of pulmonary embolism, 0; 95% CI, 0.00 to 0.55). An entrapped thrombus was found in the filter in 6 patients.

CONCLUSIONS

Early prophylactic placement of a vena cava filter after major trauma did not result in a lower incidence of symptomatic pulmonary embolism or death at 90 days than no placement of a filter. (Funded by the Medical Research Foundation of Royal Perth Hospital and others; Australian New Zealand Clinical Trials Registry number, ACTRN12614000963628.).

Evaluation of the implementation of a relationship and sexuality education project in Western Australian schools: protocol of a multiple, embedded case study

INTRODUCTION

There is recognition of the importance of comprehensive relationships and sexuality education (RSE) throughout the school years worldwide. Interventions have found some positive outcomes; however, the need for a greater focus on positive sexuality and relevant contemporary issues has been identified by teachers and students. The Curtin RSE Project provides training for teachers and preservice teachers and supports schools through training and advice to implement comprehensive school health promotion (CSHP) focusing on RSE allowing schools to develop programmes relevant to their school community. To examine contemporary phenomenon within a real word context, a case study design will be used to measure implementation. This paper will describe the protocol for a multiple, embedded case study to measure the implementation of CSHP focusing on RSE in a purposive sample of Western Australian schools.

METHODS AND ANALYSIS

This mixed methods study will include a multiple, embedded case study. Schools (n=3-4) will be purposively selected from within Western Australia based on their capacity to commit to implementing RSE as a case study school. Data will be collected from students (Grade 6 for primary school; Grades 7-12 for secondary school); teachers and other key staff and parents. Methods include school climate and school curriculum audits, documentation (collected with key staff at baseline and annually), interviews (parents and teachers at Year 2), focus groups (students at Year 2) and an online student survey (collected with students baseline and annually).

ETHICS AND DISSEMINATION

School principals will provide consent for school participation and staff and parents will provide individual consent. Student assent and parental consent will be obtained for student participants. Results will be disseminated through open-access reports, peer-reviewed journals and conference presentations.

The recently identified flavivirus Bamaga virus is transmitted horizontally by Culex mosquitoes and interferes with West Nile virus replication in vitro and transmission in vivo

Arthropod-borne flaviviruses such as yellow fever (YFV), Zika and dengue viruses continue to cause significant human disease globally. These viruses are transmitted by mosquitoes when a female imbibes an infected blood-meal from a viremic vertebrate host and expectorates the virus into a subsequent host. Bamaga virus (BgV) is a flavivirus recently discovered in Culex sitiens subgroup mosquitoes collected from Cape York Peninsula, Australia. This virus phylogenetically clusters with the YFV group, but is potentially restricted in most vertebrates. However, high levels of replication in an opossum cell line (OK) indicate a potential association with marsupials. To ascertain whether BgV could be horizontally transmitted by mosquitoes, the vector competence of two members of the Cx. sitiens subgroup, Cx. annulirostris and Cx. sitiens, for BgV was investigated. Eleven to thirteen days after imbibing an infectious blood-meal, infection rates were 11.3% and 18.8% for Cx. annulirostris and Cx. sitiens, respectively. Cx. annulirostris transmitted the virus at low levels (5.6% had BgV-positive saliva overall); Cx. sitiens did not transmit the virus. When mosquitoes were injected intrathoracially with BgV, the infection and transmission rates were 100% and 82%, respectively, for both species. These results provided evidence for the first time that BgV can be transmitted horizontally by Cx. annulirostris, the primary vector of pathogenic zoonotic flaviviruses in Australia. We also assessed whether BgV could interfere with replication in vitro, and infection and transmission in vivo of super-infecting pathogenic Culex-associated flaviviruses. BgV significantly reduced growth of Murray Valley encephalitis and West Nile (WNV) viruses in vitro. While prior infection with BgV by injection did not inhibit WNV super-infection of Cx. annulirostris, significantly fewer BgV-infected mosquitoes could transmit WNV than mock-injected mosquitoes. Overall, these data contribute to our understanding of flavivirus ecology, modes of transmission by Australian mosquitoes and mechanisms for super-infection interference.

Mosquito-borne flaviviruses include medically significant members such as the dengue viruses, yellow fever virus and Zika virus. These viruses regularly cause outbreaks globally, notably in tropical regions. The ability of mosquitoes to transmit these viruses to vertebrate hosts plays a major role in determining the scale of these outbreaks. It is essential to assess the risk of emergence of flaviviruses in a given region by investigating the vector competence of local mosquitoes for these viruses. Bamaga virus was recently discovered in Australia in Culex mosquitoes and shown to be related to yellow fever virus. In this article, we investigated the potential for Bamaga virus to emerge as an arthropod-borne viral pathogen by assessing the vector competence of Cx. annulirostris and Cx. sitiens mosquitoes for this virus. We showed that Bamaga virus could be detected in the saliva of Cx. annulirostris after an infectious blood-meal, demonstrating that the virus could be horizontally transmitted. In addition, we showed that Bamaga virus could interfere with the replication in vitro and transmission in vivo of the pathogenic flavivirus West Nile virus. These data provide further insight on how interactions between viruses in their vector can influence the efficiency of pathogen transmission.

Correlation between circulating tumour DNA and metabolic tumour burden in metastatic melanoma patients

BACKGROUND

Circulating tumour DNA (ctDNA) may serve as a measure of tumour burden and a useful tool for non-invasive monitoring of cancer. However, ctDNA is not always detectable in patients at time of diagnosis of metastatic disease. Therefore, there is a need to understand the correlation between ctDNA levels and the patients' overall metabolic tumour burden (MTB).

METHODS

Thirty-two treatment naïve metastatic melanoma patients were included in the study. MTB and metabolic tumour volume (MTV) was measured by 18F-fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT). Plasma ctDNA was quantified using droplet digital PCR (ddPCR).

RESULTS

CtDNA was detected in 23 of 32 patients. Overall, a significant correlation was observed between ctDNA levels and MTB (p < 0.001). CtDNA was not detectable in patients with an MTB of ≤10, defining this value as the lower limit of tumour burden that can be detected through ctDNA analysis by ddPCR.

CONCLUSIONS

We showed that ctDNA levels measured by ddPCR correlate with MTB in treatment naïve metastatic melanoma patients and observed a limit in tumour size for which ctDNA cannot be detected in blood. Nevertheless, our findings support the use of ctDNA as a non-invasive complementary modality to functional imaging for monitoring tumour burden.

Impact of the Four-Hour Rule in Western Australian hospitals: Trend analysis of a large record linkage study 2002-2013

BACKGROUND

In 2009, the Western Australian (WA) Government introduced the Four-Hour Rule (FHR) program. The policy stated that most patients presenting to Emergency Departments (EDs) were to be seen and either admitted, transferred, or discharged within 4 hours. This study utilised de-identified data from five participating hospitals, before and after FHR implementation, to assess the impact of the FHR on several areas of ED functioning.

METHODS

A state (WA) population-based intervention study design, using longitudinal data obtained from administrative health databases via record linkage methodology, and interrupted time series analysis technique.

FINDINGS

There were 3,214,802 ED presentations, corresponding to 1,203,513 ED patients. After the FHR implementation, access block for patients admitted through ED for all five sites showed a significant reduction of up to 13.2% (Rate Ratio 0.868, 95%CI 0.814, 0.925) per quarter. Rate of ED attendances for most hospitals continued to rise throughout the entire study period and were unaffected by the FHR, except for one hospital. Pattern of change in ED re-attendance rate post-FHR was similar to pre-FHR, but the trend reduced for two hospitals. ED occupancy was reduced by 6.2% per quarter post-FHR for the most 'crowded' ED. ED length of stay and ED efficiency improved in four hospitals and deteriorated in one hospital. Time to being seen by ED clinician and Did-Not-Wait rate improved for some hospitals. Admission rates in post-FHR increased, by up to 1% per quarter, for two hospitals where the pre-FHR trend was decreasing.

CONCLUSIONS

The FHR had a consistent effect on 'flow' measures: significantly reducing ED overcrowding and access block and enhancing ED efficiency. Time-based outcome measures mostly improved with the FHR. There is some evidence of increased ED attendance, but no evidence of increased ED re-attendance. Effects on patient disposition status were mixed. Overall, this reflects the value of investing resources into the ED/hospital system to improve efficiency and patient experience. Further research is required to illuminate the exact mechanisms of the effects of FHR on the ED and hospital functioning across Australia.

Enhanced Visualization of Subtle Outer Retinal Pathology by En Face Optical Coherence Tomography and Correlation with Multi-Modal Imaging

PURPOSE

To present en face optical coherence tomography (OCT) images generated by graph-search theory algorithm-based custom software and examine correlation with other imaging modalities.

METHODS

En face OCT images derived from high density OCT volumetric scans of 3 healthy subjects and 4 patients using a custom algorithm (graph-search theory) and commercial software (Heidelberg Eye Explorer software (Heidelberg Engineering)) were compared and correlated with near infrared reflectance, fundus autofluorescence, adaptive optics flood-illumination ophthalmoscopy (AO-FIO) and microperimetry.

RESULTS

Commercial software was unable to generate accurate en face OCT images in eyes with retinal pigment epithelium (RPE) pathology due to segmentation error at the level of Bruch's membrane (BM). Accurate segmentation of the basal RPE and BM was achieved using custom software. The en face OCT images from eyes with isolated interdigitation or ellipsoid zone pathology were of similar quality between custom software and Heidelberg Eye Explorer software in the absence of any other significant outer retinal pathology. En face OCT images demonstrated angioid streaks, lesions of acute macular neuroretinopathy, hydroxychloroquine toxicity and Bietti crystalline deposits that correlated with other imaging modalities.

CONCLUSIONS

Graph-search theory algorithm helps to overcome the limitations of outer retinal segmentation inaccuracies in commercial software. En face OCT images can provide detailed topography of the reflectivity within a specific layer of the retina which correlates with other forms of fundus imaging. Our results highlight the need for standardization of image reflectivity to facilitate quantification of en face OCT images and longitudinal analysis.

Minimal residual disease in breast cancer: an overview of circulating and disseminated tumour cells

Within the field of cancer research, focus on the study of minimal residual disease (MRD) in the context of carcinoma has grown exponentially over the past several years. MRD encompasses circulating tumour cells (CTCs)—cancer cells on the move via the circulatory or lymphatic system, disseminated tumour cells (DTCs)—cancer cells which have escaped into a distant site (most studies have focused on bone marrow), and resistant cancer cells surviving therapy—be they local or distant, all of which may ultimately give rise to local relapse or overt metastasis. Initial studies simply recorded the presence and number of CTCs and DTCs; however recent advances are allowing assessment of the relationship between their persistence, patient prognosis and the biological properties of MRD, leading to a better understanding of the metastatic process. Technological developments for the isolation and analysis of circulating and disseminated tumour cells continue to emerge, creating new opportunities to monitor disease progression and perhaps alter disease outcome. This review outlines our knowledge to date on both measurement and categorisation of MRD in the form of CTCs and DTCs with respect to how this relates to cancer outcomes, and the hurdles and future of research into both CTCs and DTCs.