University General - Research Publications
Now showing items 1-12 of 756
Changes in the modes of twin birth in Victoria, 1983-2015
OBJECTIVES: To examine changes in the modes of delivery of twins in Victoria over 33 years. DESIGN: Retrospective population-based study. SETTING, PARTICIPANTS: All twin births in Victoria, 1 January 1983 - 31 December 2015. MAJOR OUTCOMES: Mode of birth (vaginal, planned or unplanned caesarean delivery); indications for caesarean delivery. RESULTS: During 1983-2015, 32 187 twin pregnancies ended in live or stillbirths in Victoria. The proportion of twins born by caesarean delivery increased from 24% (156 twin deliveries) in 1983 to 71% (782 deliveries) in 2015. The proportion of twin births by planned caesarean delivery with twin pregnancy as the sole indication for caesarean delivery increased across this period from 1.8% (12 twin deliveries) to 21% (231 deliveries). The proportion of twin births by caesarean delivery and the proportion of caesarean twin deliveries with twin pregnancy as the principal indication each differed between Victorian regions. CONCLUSION: During 1983-2015, the proportion of twins born in Victoria by caesarean delivery increased almost threefold, mostly because caesarean delivery has become the preferred mode of birth for twin pregnancies. Regional differences in the delivery of twins suggest that the number of caesarean deliveries can be reduced with appropriate system and training support.
Initiation of vasopressor infusions via peripheral versus central access in patients with early septic shock: A retrospective cohort study
OBJECTIVE: To assess whether the initiation of vasopressor infusions via peripheral venous catheters (PVC) compared to central venous catheters (CVC) in ED patients with early septic shock was associated with differences in processes of care and outcomes. METHODS: We conducted a post-hoc analysis of the ARISE trial. We compared participants who had a vasopressor infusion first commenced via a PVC versus a CVC. The primary outcome was 90 day mortality. RESULTS: We studied 937 participants. Of these, 389 (42%) had early vasopressor infusion commenced via a PVC and 548 (58%) via a CVC. Trial participants who received a vasopressor infusion via a PVC were more severely ill, with higher median (interquartile range [IQR]) Acute Physiology And Chronic Health Evaluation (APACHE II) scores (17 [13-23] versus 16 [12-21], P = 0.003), and higher median (IQR) lactate (mmol/L) (3.6 [1.9-5.8] versus 2.5 [1.5-4.5], P < 0.001). After adjusting for baseline covariates, the estimated odds ratio for mortality for PVC-treated patients was 1.26 (95% confidence interval 0.95-1.67, P = 0.11). Trial participants who had vasopressors commenced via PVC had a shorter median (IQR) time to commencement of antimicrobials (55 [32-96] versus 71.5 [39-119] min, P < 0.001) and a shorter median (IQR) time to commencement of vasopressors (2.4 [1.3-3.9] versus 4.9 [3.5-6.6] h, P < 0.001). CONCLUSION: The practice of commencing a vasopressor infusion via a PVC was common in the ARISE trial and more frequent in trial participants with higher severity of illness. Commencement of a vasopressor infusion via a PVC was associated with some improvements in processes of care and, after adjustment, was not associated with an increased risk of death.
Resident perceptions of opportunity for communication and contribution to care planning in residential aged care
BACKGROUND AND AIM: Irrespective of age, communication is a tool of expression and a key daily activity meeting the human need for social interaction and connection. The introduction of consumer-directed care (CDC) emphasises the importance of communication to provide consumers with the opportunity to exercise choice over the care they receive. As consumer-directed care progresses, it is hypothesised that the feasibility of shared decision-making and care planning in residential aged care will be largely determined by the communication opportunities afforded to the residents. Therefore, the aim of this study was to explore resident perceptions of the opportunities they have to communicate, including the opportunity to express their care preferences and contribute opinions about their care. DESIGN: A qualitative inductive design was adopted. METHODS: An individual interview format was used to gather the perspectives of 102 residents. Data were analysed using qualitative content analysis to generate themes illustrating patterns in participant views. FINDINGS: Overall, residents desired increased involvement in their care planning and increased opportunity for more meaningful communication and social opportunities. Residents described the negative impact of the communication difficulties they face on their communication and the need for support and activities to be tailored to residents' individual communication needs. CONCLUSIONS: To facilitate resident participation in CDC and meet resident desire for increased social communication, further investment in resources to support resident-staff communication and accommodate residents' individual communication needs is required. IMPLICATIONS FOR PRACTICE: By highlighting communication as a stand-alone activity and a priority of residents, the findings of this study raise the profile of communication and demonstrate the need for explicit allocation of care time and specialist services to support resident-staff communication and social communication in residential aged care. Such support must be tailored to meet residents' individual communication needs and be coupled with increased staff training in providing communication support. Without facilitating resident communication and increasing the opportunity to communicate, shared decision-making and care planning in residential aged care consistent with person-centred and consumer-directed models of care will be limited.
Tranexamic acid modulates the cellular immune profile after traumatic brain injury in mice without hyperfibrinolysis
BACKGROUND: Traumatic brain injury (TBI) is known to promote immunosuppression, making patients more susceptible to infection, yet potentially exerting protective effects by inhibiting central nervous system (CNS) reactivity. Plasmin, the effector protease of the fibrinolytic system, is now recognized for its involvement in modulating immune function. OBJECTIVE: To evaluate the effects of plasmin and tranexamic acid (TXA) on the immune response in wild-type and plasminogen-deficient (plg-/- ) mice subjected to TBI. METHODS: Leukocyte subsets in lymph nodes and the brain in mice post TBI were evaluated by flow cytometry and in blood with a hemocytometer. Immune responsiveness to CNS antigens was determined by Enzyme-linked Immunosorbent Spot (ELISpot) assay. Fibrinolysis was determined by thromboelastography and measuring D-dimer and plasmin-antiplasmin complex levels. RESULTS: Plg-/- mice, but not plg+/+ mice displayed increases in both the number and activation of various antigen-presenting cells and T cells in the cLN 1 week post TBI. Wild-type mice treated with TXA also displayed increased cellularity of the cLN 1 week post TBI together with increases in innate and adaptive immune cells. These changes occurred despite the absence of systemic hyperfibrinolysis or coagulopathy in this model of TBI. Importantly, neither plg deficiency nor TXA treatment enhanced the autoreactivity within the CNS. CONCLUSION: In the absence of systemic hyperfibrinolysis, plasmin deficiency or blockade with TXA increases migration and proliferation of conventional dendritic cells (cDCs) and various antigen-presenting cells and T cells in the draining cervical lymph node (cLN) post TBI. Tranexamic acid might also be clinically beneficial in modulating the inflammatory and immune response after TBI, but without promoting CNS autoreactivity.
Common mechanisms of executive attention underlie executive function and effortful control in children
Executive Function (EF) and Effortful Control (EC) have traditionally been viewed as distinct constructs related to cognition and temperament during development. More recently, EF and EC have been implicated in top-down self-regulation - the goal-directed control of cognition, emotion, and behavior. We propose that executive attention, a limited-capacity attentional resource subserving goal-directed cognition and behavior, is the common cognitive mechanism underlying the self-regulatory capacities captured by EF and EC. We addressed three related questions: (a) Do behavioral ratings of EF and EC represent the same self-regulation construct? (b) Is this self-regulation construct explained by a common executive attention factor as measured by performance on cognitive tasks? and (c) Does the executive attention factor explain additional variance in attention deficit hyperactivity disorder (ADHD) problems to behavioral ratings of self-regulation? Measures of performance on complex span, general intelligence, and response inhibition tasks were obtained from 136 preadolescent children (M = 11 years, 10 months, SD = 8 months), along with self- and parent-reported EC, and parent-reported EF, and ADHD problems. Results from structural equation modeling demonstrated that behavioral ratings of EF and EC measured the same self-regulation construct. Cognitive tasks measured a common executive attention factor that significantly explained 30% of the variance in behavioral ratings of self-regulation. Executive attention failed to significantly explain additional variance in ADHD problems beyond that explained by behavioral ratings of self-regulation. These findings raise questions about the utility of task-based cognitive measures in research and clinical assessment of self-regulation and psychopathology in developmental samples.
The Interplay Between Multisensory Associative Learning and IQ in Children
This study assessed the developmental profile of unisensory and multisensory processes, and their contribution to children's intellectual abilities (8- and 11-year olds, N = 38, compared to adults, N = 19) using a simple audiovisual detection task and three incidental associative learning tasks with different sensory signals: visual-verbal with pseudowords, novel audiovisual, and visual-visual. The level of immaturity throughout childhood was dependent on both, the sensory signal type and the task. Associative learning was significantly enhanced with verbal sounds, compared to novel audiovisual and unisensory visual learning. Visual-verbal learning was also the best predictor of children's general intellectual abilities. The results demonstrate a separate developmental trajectory for visual and verbal multisensory processes and independent contributions to the development of cognitive abilities throughout childhood.
Communal responsibility: a history of health collectives in Australia
Healthcare encompasses multiple discourses to which health professionals, researchers, patients, carers and lay individuals contribute. Networks of patients and non-professionals often act collectively to build capacity, enhance access to resources, develop understanding and improve provision of care. This article explores the concept of health collectives and three notable examples that have had an enduring and profound impact in the Australian context.
Sexually transmissible infections among transgender men and women attending Australian sexual health clinics.
OBJECTIVES: To estimate rates of HIV infection, chlamydia, gonorrhoea, and infectious syphilis in transgender men and women in Australia; to compare these rates with those for cisgender people. DESIGN: Cross-sectional, comparative analysis of de-identified health data. SETTING, PARTICIPANTS: We analysed data for 1260 transgender people (404 men, 492 women, 364 unrecorded gender), 78 108 cisgender gay and bisexual men, and 309 740 cisgender heterosexual people who attended 46 sexual health clinics across Australia during 2010-2017. MAIN OUTCOME MEASURES: First-visit test positivity for sexually transmitted infections (STIs), stratified by patient group and year; demographic and behavioural factors associated with having STIs. RESULTS: 14 of 233 transgender men (6.0%) and 34 of 326 transgender women (10%) tested during first clinic visits were chlamydia-positive; nine transgender men (4%) and 28 transgender women (8.6%) were gonorrhoea-positive. One of 210 tested transgender men (0.5%) and ten of 324 tested transgender women (3.1%) were diagnosed with infectious syphilis; 14 transgender men (3.5%) and 28 transgender women (5.7%) were HIV-positive at their first visit. The only significant change in prevalence of an STI among transgender patients during the study period was the increased rate of gonorrhoea among transgender women (from 3.1% to 9.8%). Compared with cisgender gay and bisexual men, transgender men were less likely (adjusted odds ratio [aOR], 0.46; 95% CI, 0.29-0.71; P = 0.001) and transgender women as likely (aOR, 0.98; 95% CI, 0.73-1.32; P = 0.92) to be diagnosed with a bacterial STI; compared with heterosexual patients, transgender men were as likely (aOR, 0.72; 95% CI, 0.46-1.13; P = 0.16) and transgender women more likely (aOR, 1.56; 95% CI, 1.16-2.10; P = 0.003) to receive a first-visit bacterial STI diagnosis. CONCLUSIONS: The epidemiology of STIs in transgender people attending Australian sexual health clinics differs from that of cisgender patients. Gender details must be captured by health data systems to facilitate appropriate delivery of sexual health care.
Home-based pulmonary rehabilitation for COPD using minimal resources: An economic analysis
BACKGROUND AND OBJECTIVE: This study aimed to compare the cost-effectiveness and cost-utility of home and centre-based pulmonary rehabilitation for adults with stable chronic obstructive pulmonary disease (COPD). METHODS: Prospective economic analyses were undertaken from a health system perspective alongside a randomized controlled equivalence trial in which participants referred to pulmonary rehabilitation undertook a standard 8-week outpatient centre-based or a new home-based programme. Participants underwent clinical assessment prior to programme commencement, immediately following completion and 12 months following programme completion. They provided data for utility (quality-adjusted life years (QALY) determined using SF6D (utility scores for health states) calculated from 36-Item Short Form Health Survey version 2) and effectiveness (change in distance walked on 6-min walk test (Δ6MWD) following pulmonary rehabilitation ). Individual-level cost data for the 12 months following programme completion was sourced from healthcare administration and government databases. RESULTS: Between-group mean difference point estimates for cost (-$4497 (95% CI: -$12 250 to $3257), utility (0.025 (-0.038 to 0.086) QALY) and effectiveness (14 m (-11 to 39) Δ6MWD) favoured the home-based group. Cost-utility analyses demonstrated 63% of estimates falling in the dominant southeast quadrant and the probability that the new home-based model was cost-effective at a $0 threshold for willingness to pay was 78%. Results were robust to a range of sensitivity analyses. Programme completion was associated with significantly lower healthcare costs in the following 12 months. CONCLUSION: Home-based pulmonary rehabilitation provides a cost-effective alternative model for people with COPD who cannot access traditional centre-based programmes.
Oxidative stress, inflammation and risk of neurodegeneration in a population sample
BACKGROUND AND PURPOSE: Inflammation and oxidative stress (OS) have been clearly linked to neurodegeneration. However, studies investigating the associations between peripheral markers of inflammation and cognitive decline have produced mixed results. This is possibly due to the fact that markers are typically tested individually despite the fact that biologically they function interactively. Thus, the aim of this study was to investigate the association between a combination of OS/inflammation markers and outcomes including mild cognitive impairment (MCI) diagnosis, cognitive decline and hippocampal atrophy. METHODS: Oxidative stress/inflammation status was assessed in 380 older community-living individuals. Thirteen blood markers were assayed. Principal component analysis (PCA) of all markers was conducted to identify the more salient inflammatory components. Associations between significant principal components, MCI diagnosis, previous change in Mini-Mental State Examination (MMSE) score and hippocampal atrophy were investigated through logistic and linear multiple regression. RESULTS: Two factors (PC1 and PC2) reflecting predominantly broad pro-inflammatory activity and two factors (PC3 and PC4) reflecting predominantly OS activity were identified by PCA analysis. PC3 and PC4 were predictive of MCI. PC3 was also predictive of prior MMSE change. PC1, PC2 and PC3 were significantly associated with hippocampal atrophy. CONCLUSIONS: Combined analysis of complex and interacting biomarkers revealed a protective association between antioxidant activity and MCI that is consistent with lifestyle factors shown to reduce risk of cognitive decline. OS and broad systemic inflammation were also found to be associated with hippocampal atrophy further highlighting the benefits of the PCA methodology applied in this study.
Leadership and career development curriculum in Australian dental and oral health programmes
INTRODUCTION: There is very little evidence of dental schools offering leadership or career development training for students. Given that tertiary students come from diverse backgrounds with differing experiences, it is important that all students learn skills that improve their employability by preparing them for a range of career paths and equipping them with the confidence to lead their profession into the future. This study mapped current leadership and career development training in dental education programmes throughout Australia, focusing on the capacity, barriers and enablers. METHODS: In 2018, an electronic survey was sent to the Program Convenors of all nineteen dental programmes in Australia. Survey questions were sourced from existing literature and the current regulatory competencies. RESULTS: Whilst the majority of respondents (n = 17, 89% response rate) indicated that their programmes included both leadership training (72%) and career development activities (88%), it is clear that the content focus, hours allocated and assessment items vary widely across the country. Further, curriculum appeared to focus almost exclusively on clinical work, which does not provide an avenue for students to explore alternative, non-clinical career options or pathways or develop their skills beyond treating individual patients. Time constraints and ideological differences were reported as the biggest barriers to implementing leadership and career development curricula. CONCLUSION: Despite an inconsistent approach nationally, it appears there is an opportunity for faculty across institutions to collaborate, potentially to develop a set of leadership and career development competencies and best practice teaching and learning activities.