Psychiatric admissions in young people after expiration of criminal justice supervision in Australia: a retrospective data linkage study.

BACKGROUND: Mental health services are available for young people involved with the criminal justice system. However, they have unmet mental health needs after the expiration of criminal justice supervision. OBJECTIVE: To determine the incidence rate and identify predictors of psychiatric hospitalisations within 24 months after the expiration of criminal justice supervision among young people involved with the New South Wales (NSW) criminal justice system. METHODS: Retrospective data from 1556 individuals aged 14-22 years who participated in four surveys of justice-involved young people in NSW were harmonised and linked to four NSW data collections. We calculated the incidence rates of psychiatric hospitalisations within 24 months postsupervision and identified predictors of these hospitalisations using a competing risks regression analysis. RESULTS: Within 24 months postsupervision, 11.4% had a psychiatric hospitalisation compared with 3.5% during supervision. 20.7% of those admitted had a known history of mental illness and engaged with community-based and outpatient mental health services postsupervision. Predictors of psychiatric hospitalisations were: female sex (adjusted subdistribution HR (asHR) 1.84, 95% CI 1.24 to 2.73); previous incarceration (highest asHR for ≥4 episodes 1.67, 95% CI 1.01 to 2.78); head injury (asHR 1.63, 95% CI 1.20 to 2.21); personality disorder (asHR 3.66, 95% CI 2.06 to 6.48) and alcohol and substance use disorder (asHR 1.89, 95% CI 1.29 to 2.77). CONCLUSION: Justice-involved youth have higher rates of psychiatric admissions after criminal justice supervision. Engagement with mental health services postsupervision is important in addressing emerging or persisting mental health needs.

Mortality and cause of death during inpatient psychiatric care in New South Wales, Australia: A retrospective linked data study.

BACKGROUND: Premature mortality in people with mental illness is well-documented, yet deaths during inpatient psychiatric care have received little research attention. This study investigates mortality rates and causes of death during inpatient psychiatric care in New South Wales (NSW), Australia. Risk factors for inpatient death were also explored. METHODS: A retrospective cohort study using linked administrative datasets with complete capture of psychiatric admissions in NSW from 2002 to 2012 (n = 421,580) was conducted. Univariate and multivariate random-effects logistic regression analyses were used to explore risk factors for inpatient death. RESULTS: The mortality rate during inpatient psychiatric care was 1.12 deaths per 1000 episodes of care and appeared to decline over the study period. Suicide accounted for 17% of inpatient deaths, while physical health causes accounted for 75% of all deaths. Thirty percent of these deaths were considered potentially avoidable. In the multivariate model, male sex, unknown address and several physical health diagnoses were associated with increased deaths. CONCLUSIONS: The mortality rate and number of avoidable deaths during inpatient psychiatric care were substantial and warrant further systemic investigation. This was driven by a dual burden of physical health conditions and suicide. Strategies to improve access to physical health care on psychiatric inpatient wards and prevent inpatient suicide are necessary. A coordinated approach to monitoring psychiatric inpatient deaths in Australia is not currently available and much needed.

Risk factors for dementia and self-harm: A linkage study.

INTRODUCTION: 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. METHODS: 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. RESULTS: 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. DISCUSSION: 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.

Impact of post-release community mental health and disability support on reincarceration for prisoners with intellectual disability and serious mental illness in NSW, Australia.

BACKGROUND: Prisoners with an intellectual disability are overrepresented in custody and more likely to reoffend and be reincarcerated compared with the general prison population. Although prisoners with intellectual disability have many of the same risk factors for recidivism as the general prison population, the high rates of mental illness experienced by this group are key drivers of recidivism. AIMS: We aimed to assess the impact of provision of post-release disability and community mental health support on rates of reincarceration in a cohort with identified intellectual disability and serious mental illness diagnosis. METHOD: We conducted a historical cohort study using linked administrative data-sets, including data on hospital admissions, community mental health, disability support and corrections custody in New South Wales, Australia (n = 484). To assess the time to return to adult custody, we used survival analysis on multiple failure-time data. RESULTS: Over the median follow-up period of 7.4 years, 73.7% (357) received community mental health support, 19.8% (96) received disability support and 18.6% (85) received a combination of supports during a post-release period from prison. Lower hazards of reincarceration in a post-release period were associated with receipt of community mental health support (hazard ratio [HR] = 0.58, CI 0.49-0.69, P < 0.001), or a combination of community mental health and disability support (HR = 0.46, CI 0.34-0.61, P < 0.001). CONCLUSIONS: High rates of reincarceration for prisoners with intellectual disability and history of serious mental illness may be modifiable by provision of appropriate mental health and disability supports.

Hospital service utilisation of people previously hospitalised with different subtypes of psychotic disorder: A record linkage study.

OBJECTIVE: 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 individuals previously hospitalised with various psychotic disorder subtypes using linked health service data. METHODS: We included individuals 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. RESULTS: 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). CONCLUSION: 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.

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.

Factors associated with discharge from hospital to residential aged care for younger people with neuropsychiatric disorders: an exploratory case-control study in New South Wales, Australia.

OBJECTIVES: 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. DESIGN: 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. SETTING: Public and private hospital admissions in New South Wales (NSW), Australia. PARTICIPANTS: People aged 15-64 years with a neuropsychiatric disorder hospitalised in NSW between July 2002 and June 2015 (n=5 16 469). OUTCOME MEASURES: 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. RESULTS: 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. CONCLUSIONS: 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.

Readmission and emergency department presentation after hospitalisation for epilepsy in people with intellectual disability: A data linkage study.

BACKGROUND: Despite the high prevalence of epilepsy and multiple barriers to care in people with intellectual disability, the risk of returning to hospital after an admission for epilepsy is largely unknown. In this study, we sought to quantify and compare readmission and emergency department (ED) presentations after hospitalisation for epilepsy in people with and without intellectual disability. METHODS AND FINDINGS: Using linked administrative datasets, we conducted a retrospective cohort study of people aged 5-64 years with an acute hospitalisation for epilepsy from 2005-2014 in New South Wales, Australia. Acute readmission and ED presentation rates within 30, 90, and 365 days of the index hospitalisation were estimated and compared between people with and without intellectual disability using modified Poisson regression. Of 13537 individuals with an index hospitalisation, 712 children and 1862 adults had intellectual disability. Readmission and ED presentation after the index hospitalisation were common in people with intellectual disability. Within 30 days, 11% of children and 15.6% of adults had an all-cause readmission and 18% of children and 23.5% of adults had an ED presentation. Over 60% of both children and adults presented to an ED within a year. Neurological, respiratory, and infectious conditions were overrepresented reasons for readmission in people with intellectual disability. Age-adjusted relative risks (RRs) within each period showed a higher risk of readmission and ED presentation in children and adults with intellectual disability than without. Most RRs remained statistically significant after controlling for covariates. The largest adjusted RRs were observed for readmission for epilepsy (RR 1.70, 95% CI: 1.42 to 2.04) and non-epilepsy related conditions (RR 1.73, 95%: CI 1.43 to 2.10) in children. Study limitations include lack of clinical data. CONCLUSIONS: Increased risk of returning to acute care after epilepsy hospitalisation suggests there is a need to improve epilepsy care for people with intellectual disability. We recommend research into strategies to improve management of both seizures and comorbidity.

Mortality rate, risk factors, and causes of death in people with epilepsy and intellectual disability.

PURPOSE: The extent to which co-occurring intellectual disability influences mortality in people with epilepsy is largely unknown. This study compares mortality rates in people with epilepsy with and without intellectual disability and investigates causes of death and risk factors for mortality. METHOD: This retrospective cohort study used linked population-based administrative datasets to derive a cohort of people with epilepsy admitted to hospital from 2005-2015 in New South Wales, Australia. We calculated mortality rates for those with and without intellectual disability and compared them by estimating relative mortality risks with modified Poisson regression. Leading causes of death were summarised. We investigated risk factors for death in people with intellectual disability by fitting Poisson regression. RESULTS: Of 28500 people hospitalised with an epilepsy diagnosis, 6029 had intellectual disability, 863 (14.3%) of whom died during follow-up. Sex and age-adjusted relative mortality risks showed that people with intellectual disability had higher mortality than those without, with the highest risk in females and peaking at age 5 (males: 1.88, 95%CI 1.28-2.48; females: 2.73, 95%CI 1.84-3.62), then decreasing with age. Neurological, respiratory, and endocrine, nutritional, and metabolic disorders were overrepresented causes of death in people with intellectual disability. The risk factors for death were older age, disability service use and several specific comorbidities. CONCLUSION: Children and young adults with epilepsy and intellectual disability are at greater risk of dying than those with epilepsy alone. Our data highlight the potential to reduce the excess risk by improved management of epilepsy and comorbid conditions.

Predictors and outcomes of recognition of intellectual disability for adults during hospital admissions: A retrospective data linkage study in NSW, Australia.

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 10th 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.

The health service contact patterns of people with psychotic and non-psychotic forms of severe mental illness in New South Wales, Australia: A record-linkage study.

OBJECTIVE: To describe and compare the health profiles and health service use of people hospitalised with severe mental illness, with and without psychotic symptoms. METHODS: 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 individuals 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. RESULTS: 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. CONCLUSION: 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.

Predictors of the Quality of Life of Informal Carers of Adults on the Autism Spectrum.

Carers of adults on the autism spectrum often experience high levels of stress, worry, and caregiver burden. There are few studies identifying the predictors of carer mental well-being and none have been conducted in Australia. Data from the Autism Cooperative Research Centre for Living with Autism's Australian Longitudinal Study of Autism in Adulthood was used to test the conceptual model by Sonido et al. (Rev J Autism Dev Disord, 2019, https://doi.org/10.1007/s40489-019-00177-8 ) by (a) identifying the predictors of mental well-being for carers of adults on the spectrum, (b) using model selection to determine which predictors contribute to the model of best fit, and (c) testing for mediating relationships between the predictors. Several predictors were directly associated with carer psychological quality of life, including carer age, care recipient intellectual disability, and carer intolerance of uncertainty. Model selection strongly supported the inclusion of most clusters from the conceptual model. Some mediating relationships were found, such as care recipient depressive behaviours mediating the relationships between caregiver burden and psychological quality of life. Future studies of the conceptual model will improve understanding of the predictors of carer mental well-being and enable tailored interventions to improve the psychological health of carers of adults on the autism spectrum.

Public mental health service use by people with intellectual disability in New South Wales and its costs.

OBJECTIVES: To describe the population characteristics of people with intellectual disability in New South Wales; to quantify and compare public mental health service use and costs for people with and without intellectual disability in NSW during 2014-15. DESIGN: Retrospective cohort data linkage analysis. SETTING, PARTICIPANTS: People using publicly funded in- or outpatient (admitted or non-admitted) mental health services in NSW, 2014-15. MAIN OUTCOME MEASURES: Numbers of bed days (inpatient mental health services), and treatment days (ambulatory mental health); costs of publicly funded mental health services. RESULTS: People with intellectual disability comprised 1.1% of the NSW population, but 6.3% of people who used public mental health services; 12% of public mental health costs during 2014-15 were for people with intellectual disability. Compared with metropolitan local health districts (LHDs), overall public mental health service costs were lower for rural and regional LHDs (adjusted incidence rate ratio [aIRR], 0.8; 95% CI, 0.8-0.9) and higher for specialty networks (aIRR, 1.2; 95% CI, 1.1-1.3). Per person costs for people with intellectual disability were higher than for those without intellectual disability (aIRR, 2.6; 95% CI, 2.2-3.0). CONCLUSION: People with intellectual disability use public mental health services to a greater degree than other people. They should be explicitly considered by all tiers of mental health policy and service planning in Australia. Population health planning for the needs of people with disabilities would be assisted by including disability identifiers in all health administrative data sets.

Potentially preventable hospitalisations of people with intellectual disability in New South Wales.

OBJECTIVE: To determine rates of potentially preventable hospitalisation of people with intellectual disability in New South Wales, and compare them with those for the NSW population. DESIGN: Retrospective cohort study. SETTING: Potentially preventable hospitalisations in NSW, as defined by the National Healthcare Agreement progress indicator 18, 1 July 2001 - 30 June 2015. PARTICIPANTS: Data collected in a retrospective data linkage study of 92 542 people with intellectual disability in NSW; potentially preventable hospitalisations data for NSW published by HealthStats NSW. MAIN OUTCOME MEASURES: Age-adjusted rates of potentially preventable hospitalisation by group (people with intellectual disability, NSW population), medical condition type (acute, chronic, vaccine-preventable), and medical condition. RESULTS: The annual age-standardised rate for people with intellectual disability ranged between 5286 and 6301 per 100 000 persons, and for the NSW population between 1278 and 1511 per 100 000 persons; the rate ratio (RR) ranged between 3.5 (95% CI, 3.3-3.7) in 2014-15 and 4.5 (95% CI, 4.2-4.9) in 2002-03. The difference was greatest for admissions with acute (RR range: 5.3 [95% CI, 4.9-5.7] in 2014-15 to 8.1 [95% CI, 7.4-8.8] in 2002-03) and vaccine-preventable conditions (RR range: 2.1 [95% CI, 1.6-3.0] in 2007-08 to 3.4 [95% CI, 2.2-5.2] in 2004-05). By specific condition, the highest age-standardised rate was for admissions with convulsions and epilepsy (all years, 2567 per 100 000 population; v NSW population: RR, 22.2; 95% CI, 21.3-23.1). CONCLUSION: Age-standardised rates of potentially preventable hospitalisation are higher for people with intellectual disability than for the general population. The reasons for these differences should be investigated, and strategies for averting potentially preventable hospitalisation developed.

Health Profiles, Health Services Use, and Transition to Dementia in Inpatients With Late-Life Depression and Other Mental Illnesses.

OBJECTIVES: Depression has been reported as a risk factor for dementia. We compared health and health service use profiles in older people hospitalized with late-life depression and older people hospitalized with other mental illnesses and examined the transition to dementia. DESIGN: A retrospective population-based study using linked administrative health data over 11 years. SETTING AND PARTICIPANTS: The sample includes 55,717 inpatients age 65+ years with depression and 104,068 inpatients age 65+ years with other mental illnesses in New South Wales, Australia. METHODS: The risk of subsequent dementia under consideration of sociodemographics, comorbidities, and health service use was analyzed with logistic regression. RESULTS: The most prominent differences were the rates of delirium and self-harm with a 6 times lower rate of delirium and an 8 times higher rate of self-harm in people with late-life depression compared with those with other mental illness. Inpatients with late-life depression had an increased risk of subsequent dementia by 12% and received a dementia diagnosis at a younger age compared with inpatients with other mental illnesses. Besides depression only 3 other conditions, delirium, diabetes, and cerebrovascular accidents, were associated with an increased dementia risk. Other factors associated with an increased dementia risk were longer hospital stays, low socioeconomic status, male sex, and older age. CONCLUSIONS AND IMPLICATIONS: Results from this study lead to a better understanding of the risk for dementia and of differences in health profiles and health services use in older people with depression compared with those with other mental illnesses. Our findings highlight the importance of the clinical management and prevention of self-harm and delirium in older people.

Impact of disability services on mental health service utilization in adults with intellectual disability.

BACKGROUND: Can disability support services (DS) facilitate access to mental health services (MHS) for people with intellectual disability? This study utilized 10 years of data from 6,260 persons in NSW who had received DS and specific MHS to quantify the relationship between DS utilization and MHS utilization in adults with intellectual disability and co-existing mental illness. RESULTS: Receipt of DS was associated with greater odds of accessing community mental health (CMH) services (36%, 95% CI 29%-43%) but not psychiatric admissions. Age, sex and social disadvantage did not affect the odds of psychiatric admission or CMH use. Individuals living in a remote area had greater odds of CMH use and lesser odds of psychiatric admission. CONCLUSIONS: Receipt of DS was associated with greater CMH but not psychiatric hospital utilization in people with intellectual disability and co-existing mental illness.

Prevalence of intellectual disability in New South Wales, Australia: a multi-year cross-sectional dataset by Local Government Area (LGA).

The presented dataset relates to a research project titled "My Home My Community" undertaken at University of Technology Sydney (UTS) which has been funded by the National Disability Insurance Agency (NDIA) Australia. The dataset reports estimated prevalence rates of Intellectual Disability in NSW by local government area (LGA) from 2010 - 2015. The dataset is a re-examination of a cohort of 92, 542 people with intellectual disability from a larger linked research dataset built by the Department of Developmental Disability Neuropsychiatry, School of Psychiatry, UNSW. The dataset in this paper is presented in a multi-year cross-sectional format. The cohort of people with Intellectual Disability was analysed to estimate, quantify and visualise where people with intellectual disability live in New South Wales (NSW). The cohort analysed in this dataset had been generated in an earlier project undertaken by the UNSW-based authors. This dataset was generated to share with local governments in Australia and has the potential to be more widely used in a range of health policy and planning research, and city and regional planning research environments. It represents one of the only datasets currently available in Australia on Intellectual Disability describing prevalence rates at a local government area level. This dataset allows for population comparisons in other Australian states and internationally and can be examined in combination with other social and economic datasets to continue to build evidence about disability, planning and geography.

Understanding anxiety in adults on the autism spectrum: An investigation of its relationship with intolerance of uncertainty, sensory sensitivities and repetitive behaviours.

Anxiety is present in high rates in both children and adults on the autism spectrum. An increasing number of studies have highlighted the potentially important role that intolerance of uncertainty may have in anxiety for those on the spectrum, as well as their interrelationships with sensory sensitivities and repetitive behaviours. In response to a lack of studies involving adults, this study examined self-report survey data regarding intolerance of uncertainty, sensory sensitivities, repetitive behaviours and anxiety in a sample of 176 adults on the autism spectrum (mean age = 42). Intolerance of uncertainty and anxiety were both found to be elevated relative to non-autistic adults (N = 116) and significant, positive correlations were found between intolerance of uncertainty, anxiety, repetitive behaviours and sensory sensitivities in those on the spectrum. Intolerance of uncertainty was found to be a significant mediator between sensory sensitivities and anxiety, as well as between anxiety and insistence on sameness behaviours. These results were not sensitive to age. Intolerance of uncertainty is an important factor to be considered in the conceptualisation and management of elevated rates of anxiety for adults on the autism spectrum.