ORCID Profile
0000-0003-0801-2316
Current Organisation
UNSW Sydney
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Publisher: Wiley
Date: 05-2023
DOI: 10.1002/ALZ.13080
Abstract: People living with dementia experience poor mental health and high rates of self‐harm. We investigated risk factors for self‐harm in people aged 40 years living with dementia and risk factors for dementia after self‐harm. Using linked hospital data from New South Wales, Australia, we defined a dementia cohort ( n = 154,811) and a self‐harm cohort ( n = 28,972). Using survival analyses, we investigated predictors of self‐harm for the dementia cohort, and predictors of dementia for the self‐harm cohort. We found self‐harm or dementia diagnoses occurred most often within 24 months of a dementia diagnosis or initial self‐harm presentation, respectively. Men living with dementia, and people with complex psychiatric profiles, had the greatest risk of self‐harm. Men who had self‐harmed had the greatest risk of dementia diagnoses. Men and people with complex psychiatric profiles and dementia may particularly benefit from post‐diagnosis mental and behavioral support to reduce risk of self‐harm.
Publisher: SAGE Publications
Date: 03-08-2022
DOI: 10.1177/00048674221115642
Abstract: Little research has examined the physical and mental comorbidities, and health service use patterns, of people diagnosed with psychotic disorder subtypes other than schizophrenia spectrum disorders. This study aims to examine the physical and mental comorbidities, and subsequent hospital service use patterns, of in iduals previously hospitalised with various psychotic disorder subtypes using linked health service data. We included in iduals hospitalised with a psychotic disorder in New South Wales, Australia, between 1 July 2002 and 31 December 2014 (N = 63,110). We examined the demographic profile of the cohort and rates of subsequent acute hospital care and ambulatory mental health service use. We compared the rates of subsequent hospital admissions, emergency department presentations and ambulatory mental health treatment days of people hospitalised with different psychotic disorder subtypes to people hospitalised with schizophrenia spectrum disorders using Poisson regression. People most recently hospitalised with mood/affective disorders and psychotic symptoms had a higher rate of subsequent hospital admissions than those most recently hospitalised with schizophrenia spectrum and delusional disorders (adjusted incident rate ratio = 1.06 95% confidence interval = [1.02, 1.10]), while people most recently hospitalised with drug-induced and other organic (adjusted incident rate ratio = 1.19 95% confidence interval = [1.12, 1.27]) and acute psychotic disorders (adjusted incident rate ratio = 1.10 95% confidence interval = [1.03, 1.18]) had more subsequent emergency department presentations than those most recently hospitalised with schizophrenia spectrum and delusional disorders. All three groups had fewer subsequent mental health ambulatory days than those most recently hospitalised with schizophrenia spectrum and delusional disorders (adjusted incident rate ratios = 0.85–0.91). The health profiles and subsequent hospital service use patterns of people previously hospitalised with different psychotic disorder subtypes are heterogeneous, and research is needed to develop targeted health policies to meet their specific health needs.
Publisher: SAGE Publications
Date: 13-07-2022
DOI: 10.1177/00048674211031483
Abstract: To describe and compare the health profiles and health service use of people hospitalised with severe mental illness, with and without psychotic symptoms. We conducted a historical cohort study using linked administrative datasets, including data on public hospital admissions, emergency department presentations and ambulatory mental health service contacts in New South Wales, Australia. The study cohort comprised 169,306 in iduals aged 12 years and over who were hospitalised at least once with a mental health diagnosis between 1 July 2002 and 31 December 2014. Of these, 63,110 had a recorded psychotic illness and 106,196 did not. Outcome measures were rates of hospital, emergency department and mental health ambulatory service utilisation, analysed using Poisson regression. People with psychotic illnesses had higher rates of hospital admission (adjusted incidence rate ratio (IRR) 1.26 95% confidence interval [1.23, 1.30]), emergency department presentation (adjusted IRR 1.17 95% confidence interval [1.13, 1.20]) and ambulatory mental health treatment days (adjusted IRR 2.90 95% confidence interval [2.82, 2.98]) than people without psychotic illnesses. The higher rate of hospitalisation among people with psychotic illnesses was driven by mental health admissions while people with psychosis had over twice the rate of mental health admissions, people with other severe mental illnesses without psychosis (e.g. mood/affective, anxiety and personality disorders) had higher rates of physical health admissions, including for circulatory, musculoskeletal, genitourinary and respiratory disorders. Factors that predicted greater health service utilisation included psychosis, intellectual disability, greater medical comorbidity and previous hospitalisation. Findings from this study support the need for (a) the development of processes to support the physical health of people with severe mental illness, including those without psychosis (b) a focus in mental health policy and service provision on people with complex support needs, and (c) improved implementation and testing of integrated models of care to improve health outcomes for all people experiencing severe mental illness.
Publisher: BMJ
Date: 12-2022
DOI: 10.1136/BMJOPEN-2022-065982
Abstract: To examine the sociodemographic and diagnostic factors associated with a discharge from hospital to residential aged care (RAC) for younger people (aged 15-64 years) with neuropsychiatric disorders. An exploratory case-control study using a historic cohort of people with neuropsychiatric disorders. Cases were people transferred to RAC on hospital discharge during the study period. Controls were people not transferred to RAC on discharge during the study period. Public and private hospital admissions in New South Wales (NSW), Australia. People aged 15-64 years with a neuropsychiatric disorder hospitalised in NSW between July 2002 and June 2015 (n=5 16 469). The main outcome was transferred to RAC on discharge from hospital. We calculated ORs for sociodemographic and diagnostic factors to determine factors that may impact discharge to RAC. During the period of data capture, 4406 people were discharged from hospitals to RAC. Discharge to RAC was most strongly associated with diagnoses of progressive neurological and cognitive disorders. Acute precipitants of RAC transfer included a broad range of conditions and injuries (eg, Wernicke's encephalopathy, stroke, falls) in the context of issues such as older age, not being partnered (married or de facto), living in areas of lower socioeconomic status, functional issues and the need for palliative care. There are multiple intersecting and interacting pathways culminating in discharge from hospital to RAC among younger people with neuropsychiatric disorders. Improved capacity for interdisciplinary home care and alternative housing and support options for people with high support needs are required.
Publisher: Springer Science and Business Media LLC
Date: 07-05-2021
DOI: 10.1186/S41235-021-00302-4
Abstract: People often need to update representations of information upon discovering them to be incorrect, a process that can be interrupted by competing cognitive demands. Because anxiety and stress can impair cognitive performance, we tested whether looming threat can similarly interfere with the process of updating representations of a statement’s truthfulness. On each trial, participants saw a face paired with a personality descriptor. Each pairing was followed by a signal indicating whether the pairing was “true”, or “false” (a negation of the truth of the statement), and this signal could be followed by a warning of imminent electric shock (i.e., the looming threat). As predicted, threat of shock left memory for “true” pairings intact, while impairing people’s ability to label negated pairings as untrue. Contrary to our predictions, the pattern of errors for pairings that were negated under threat suggested that these mistakes were at least partly attributable to participants forgetting that they saw the negated information at all (rather than being driven by miscategorization of the pairings as true). Consistent with this, linear ballistic accumulator modelling suggested that this impaired recognition stemmed from weaker memory traces rather than decisional processes. We suggest that arousal due to looming threat may interfere with executive processes important for resolving competition between mutually suppressive tags of whether representations in memory are “true” or “false”.
Publisher: Wiley
Date: 05-10-2021
DOI: 10.1111/JIR.12888
Abstract: People with intellectual disability (ID) have a much higher mortality rate than the general population. To reduce the rate of mortality of people with ID, it is critical that causes of death are properly understood, recorded and reported. Formal reviews of causes of death are used in some countries to ensure that causes of death are accurate. To date, the impact of these formal reviews on understanding causes of death of people with ID has not been quantified. The study aimed to quantify the impact of formal reviews of deaths on the understanding of causes of death of people with ID who died while living in residential care. In iduals (851) with ID who died in residential care in New South Wales (NSW), Australia, between 1 December 2002 and 31 December 2013, who had a cause of death recorded in both the NSW Cause of Death Unit Record File (COD-URF cause of death recorded at time of death) and NSW Ombudsman dataset (cause of death recorded after in-depth review) were included in the study. We assessed agreement in coding for cause of death by comparing the International Classification of Diseases 10th Revision (ICD-10) codings at three levels of diagnostic specificity, for both underlying and additional causes of death. We conducted our analysis through both descriptive comparison and through two boosted regression trees. Approximately half of the underlying causes of death were different after review by the NSW Ombudsman compared with the COD-URF. Certain causes of death (determined by ICD-10 chapter) were less likely to predict matches between the dataset than others, with in iduals with mental, behavioural and neurodevelopmental disorders recorded in the COD-URF least likely to have a matching cause of death in NSW Ombudsman dataset. For deaths where there was no agreement at any level between the datasets, a high level of unknown causes of death was recorded. Formal review of deaths of people with ID in residential care is important to determining true causes of death and therefore developing appropriate health policy for people with ID.
Publisher: Springer Science and Business Media LLC
Date: 19-08-2019
DOI: 10.3758/S13423-019-01653-2
Abstract: The exploitation-exploration (EE) trade-off describes how, when making a decision, an organism must often choose between a safe alternative with a known pay-off, and one or more riskier alternatives with uncertain pay-offs. Recently, the concept of the EE trade-off has been extended to the examination of how organisms distribute limited attentional resources between several stimuli. This work suggests that when the rules governing the environment are certain, participants learn to "exploit" by attending preferentially to cues that provide the most information about upcoming events. However, when the rules are uncertain, people "explore" by increasing their attention to all cues that may provide information to help in predicting upcoming events. In the current study, we examine how uncertainty affects the EE trade-off in attention using a contextual two-armed bandit task, where participants explore with both their attention and their choice behavior. We find evidence for an influence of uncertainty on the EE trade-off in both choice and attention. These findings provide support for the idea of an EE trade-off in attention, and that uncertainty is a primary motivator for exploration in both choice and attentional allocation.
Publisher: Queensland University of Technology
Date: 07-03-2019
Abstract: Peer mentoring programs are typically designed to support students transitioning into university. However, recent work has highlighted the importance of supporting transitions through and out of university. The Australian psychology honours year is a particularly stressful period that involves transitioning through university into the research environment and is soon followed by transitions into the workforce or postgraduate study. The School of Psychology at the University of New South Wales, Australia (UNSW) recently developed a graduate/honours peer mentoring program. Pairs of PhD students mentor small groups of honours students in monthly meetings, discussing various aspects of honours and career options. Most honours students sign up for mentoring and evaluation results show that mentees find the program helpful, most frequently acknowledging that their mentors helped them with general advice and understanding their career options. Peer mentoring can therefore support psychology student transitions through and out of university.
Publisher: Public Library of Science (PLoS)
Date: 25-03-2022
DOI: 10.1371/JOURNAL.PONE.0266051
Abstract: Adults with intellectual disability have high health care needs. Despite frequent contact with health services, they often receive inadequate health care. One method to improve health care delivery is reasonable adjustments, that is, the adaptation of health care delivery such that barriers to participation are removed for the person with disability. A starting point for the provision of reasonable adjustments is recognition of intellectual disability during the health care contact. To determine rates and predictors of the recognition of intellectual disability during hospital admissions, and its impact on admission metrics, we examined a population of adults with intellectual disability identified from disability services datasets from New South Wales, Australia between 2005 and 2014. Recognition of intellectual disability was determined by the recording of an International Classification of Diseases 10 th revision (ICD-10) diagnostic code for intellectual disability during a given hospital admission. We examined how recognition of intellectual disability related to length of hospital episodes. We found an overall low rate of recognition of intellectual disability (23.79%) across all hospital episodes, with the proportion of hospital episodes recognising intellectual disability decreasing from 2005–2015. Admissions for adults with complex health profiles (e.g., those with many comorbidities, those with Autism Spectrum Disorder, and those admitted for urgent treatment) were more likely to recognise intellectual disability, but admissions for adults with complexity in other domains (i.e., for those in custody, or those with drug and alcohol disorders) were less likely to recognise intellectual disability. Recognition of intellectual disability was associated with longer episodes of care, possibly indicating the greater provision of reasonable adjustments. To improve the recognition of intellectual disability for adults during health service contacts, we advocate for the implementation of targeted initiatives (such as a nationwide disability flag to be included in health service records) to improve the provision of reasonable adjustments.
Publisher: American Psychological Association (APA)
Date: 04-2022
DOI: 10.1037/XLM0000883
Abstract: The exploration/exploitation trade-off (EE trade-off) describes how, when faced with several competing alternatives, decision-makers must often choose between a known good alternative (exploitation) and one or more unknown but potentially more rewarding alternatives (exploration). Prevailing theory on how humans perform the EE trade-off states that uncertainty is a major motivator for exploration: the more uncertain the environment, the more exploration that will occur. The current article examines whether exploratory behavior in both choice and attention may be impacted differently depending on whether uncertainty is onset suddenly (unexpected uncertainty), or more slowly (expected uncertainty). It is shown that when uncertainty was expected, participants tended to explore less with their choices, but not their attention, than when it was unexpected. Crucially, the impact of this "protection from uncertainty" on exploration only occurred when participants had an opportunity to learn the structure of the task before experiencing uncertainty. This suggests that the interaction between uncertainty and exploration is more nuanced than simply more uncertainty leading to more exploration, and that attention and choice behavior may index separate aspects of the EE trade-off. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
Publisher: American Medical Association (AMA)
Date: 22-06-2021
No related grants have been discovered for Adrian Walker.