Introduction and AimsCognitive impairment is a common feature of individuals with substance‐use disorders. However, research tends to exclude highly complex clinical cases, limiting the generalisability of findings for ‘real‐world' populations. The objective of this study was to examine the complexities associated with addiction, substance use and cognitive impairment through the characterisation of client presentations to a newly established specialised addiction neuropsychology service.Design and MethodsRetrospective case file audit. Neuropsychological assessment reports for consenting clients over a 4‐year period were de‐identified and reviewed. Cognitive domains assessed included attention, processing speed, working memory, intellectual functioning, memory and executive functioning.ResultsOf the 200 case files examined, the majority were male clients, with 11 years or lower of education and a history of daily substance use, with 30% continuing to use daily. Seventy‐one percent had a formal mental health diagnosis and 41% had reported a history of trauma. The most prevalent cognitive impairments were observed in complex attention (50%) and memory (40%). New diagnoses were conveyed in 25% of cases, comprising acquired brain injury (16%) and neurodevelopmental disabilities (9%).Discussion and ConclusionsIt is common for clients with substance use histories referred to an addiction neuropsychology service to present with complex histories including psychosocial difficulties, comorbid mental health and medical issues and cognitive impairment. As such, careful diagnostic formulations are required when multiple factors may contribute to cognitive deficits. This study highlights the importance of a state‐wide specialist addiction neuropsychology service in supporting diagnostic clarification and informing relevant treatment approaches.

Introduction: Cognitive impairment is common in individuals presenting to alcohol and other drug (AOD) settings and the presence of biopsychosocial complexity and health inequities can complicate the experience of symptoms and access to treatment services. A challenge for neuropsychologists in these settings is to evaluate the likely individual contribution of these factors to cognition when providing an opinion regarding diagnoses such as acquired brain injury (ABI). This study therefore aimed to identify predictors of cognitive functioning in AOD clients attending for neuropsychological assessment. Methods: Clinical data from 200 clients with AOD histories who attended for assessment between 2014 and 2018 were analysed and a series of multiple regressions were conducted to explore predictors of cognitive impairment including demographic, diagnostic, substance use, medication, and mental health variables. Results: Regression modelling identified age, gender, years of education, age of first use, days of abstinence, sedative load, emotional distress and diagnoses of ABI and developmental disorders as contributing to aspects of neuropsychological functioning. Significant models were obtained for verbal intellectual functioning (Adj R2 = 0.19), nonverbal intellectual functioning (Adj R2 = 0.10), information processing speed (Adj R2 = 0.20), working memory (Adj R2 = 0.05), verbal recall (Adj R2 = 0.08), visual recall (Adj R2 = 0.22), divided attention (Adj R2 = 0.14), and cognitive inhibition (Adj R2 = 0.07). Conclusions: These findings highlight the importance of careful provision of diagnoses in clients with AOD histories who have high levels of unmet clinical needs. They demonstrate the interaction of premorbid and potentially modifiable comorbid factors such as emotional distress and prescription medication on cognition. Ensuring that modifiable risk factors for cognitive impairment are managed may reduce experiences of cognitive impairment and improve diagnostic clarity.

ObjectiveIn considering the cognitive harms of methamphetamine (MA) use, there is currently a limited appreciation of the profile of pre-existing, comorbid, or modifiable risk factors for cognitive impairment in individuals with MA-polydrug use who present to clinical services. This is in contrast to the well-recognized evidence in alcohol use groups. The aim of this study was to investigate the biopsychosocial and neuropsychological profiles of MA-polysubstance using individuals reporting cognitive impairment in comparison to an alcohol-using group.MethodsA retrospective file audit was undertaken of individuals who presented for assessment to a specialist addiction neuropsychology service and reported either more than 1 year of heavy MA use as part of a polydrug use history (n = 40) or having only used alcohol (n = 27). Clinical histories including demographic, medical, mental health, substance use, and neuropsychological assessment results were extracted from medical records. Between group comparisons were conducted to explore differences in the MA-polydrug vs. the alcohol group.ResultsIndividuals in the MA-polydrug group were significantly younger, commenced substance use at an earlier age, were more likely to have an offending history, and experienced an overdose than those in the alcohol group. No differences in comorbid neurodevelopmental, psychiatric or acquired brain injury diagnoses were observed between groups. For neuropsychological functioning, significant group differences were observed in overall IQ, semantic verbal fluency, and psychomotor tracking, where individuals in the alcohol group performed significantly worse.ConclusionsNeuropsychological profiles were largely equivalent between groups across cognitive domains, with minor differences in favor of the MA-polydrug group. Relative to the general population, cognitive functioning was reduced for both groups across a range of domains. High rates of comorbid mental health concerns were common across both groups, however, individuals in the MA-polydrug group presented with a higher risk of overall harm from substance use at a significantly younger age which is a unique concern for this group. These findings highlight the importance of considering the biopsychosocial factors, such as age of first use, emotional distress, indirect substance related harms including overdose and blood born virus infection that may be relevant to experiences of cognitive difficulty in MA-polydrug users.

Background and Objectives: Sleep problems are common among clients attending alcohol and drug services, yet the specific components of sleep disturbed by primary drug of concern (PDOC), and their relationships to affective disorder symptoms are unclear. Methods:We examined sleep problems in clients (n = 32) attending a specialist addiction clinic.Results: Global sleep quality was rated poor by >90% of participants (particularly disturbances, latency and efficiency components), with significant associations (p < .05) between poor sleep quality and depression (r = .517), anxiety (r = .571) and stress (r = .503). Sleep quality was significantly poorer among those with a nonalcohol PDOC compared with alcohol as PDOC, t(22) = 3.09, p = .005. Conclusion and ScientificSignificance: Poor sleep is almost ubiquitous among clients attending alcohol and drug services. However, components of sleep quality disturbed differ in terms of PDOC, highlighting the need for individualised sleep interventions.