Browsing by Author "Addington, Jean"
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- ItemOpen AccessA Study of Symptom Content of Perceptual Abnormalities in Individuals at Clinical High Risk of Psychosis(2017) Lu, Yun; Addington, Jean; Addington, Donald; Protzner, Andrea; Piskulic, DanijelaPerceptual abnormalities (PA) are frequently endorsed attenuated psychotic symptoms in youth at clinical high risk (CHR) of psychosis. However, few studies have explored the subtypes of PA and their relationships with the above environmental and affective factors in CHR. Four hundred and forty one CHR individuals who met criteria for attenuated psychotic symptom syndrome (APSS) determined by the Structured Interview for Psychosis-risk Syndromes (SIPS) were assessed on content of PA, early traumatic experience, cannabis use and self-reported anxiety, attention and auditory sensory processing. Overall, it was found that both simple auditory and simple visual PA were associated with traumatic experiences, current cannabis use and increased anxiety. In addition, complex auditory PA were found to be linked to reduced attention. There was no evidence to support a relationship between auditory PA and electrophysiological measure of auditory sensory processing. Furthermore, those who made the transition to a full-blown psychosis were more likely to have complex auditory PA. Finally, for those who did convert to psychosis, an examination of any changes in content from baseline to the time of conversions suggested that PA content progressed to being more specific and concrete, with more modalities involved and with a development of delusional attributions. The results of this study suggest that simple PA might be secondary symptoms of trauma, cannabis use and anxiety rather than early signs of a psychotic disorder. Early presence of complex auditory PA at prodromal stage could potentially be considered as an indicator for later psychotic outcome.
- ItemOpen AccessAdolescent Mental Health: Canadian Psychiatric Risk and Outcome Study (PROCAN)- Exercise Intervention Pilot Study(2019-01-16) Corbett, Syl; Addington, Jean; MacQueen, Glenda M.; Bray, Signe L.; Swain, Mark GordonBACKGROUND: The Canadian Psychiatric Risk and Outcome Study (PROCAN), a longitudinal study of youth at risk of serious mental illness (SMI), aims to better understand the trajectory of SMI. This study was conducted as a pilot exercise intervention on a subsample of the PROCAN cohort. OBJECTIVES: The primary objective was to examine the feasibility of an exercise intervention in youth at risk of SMI. The secondary objectives were to determine whether symptoms of mental illness and memory would improve, and hippocampal volume would increase, following participation in a moderate to high intensity aerobic exercise program. METHODS: Forty-four male and female youth at risk of SMI were recruited through the PROCAN project. Participants completed clinical, cognitive, neuroimaging and fitness assessments prior to and following a sixteen-week moderate to high intensity aerobic exercise intervention. Sixty-minute exercise sessions were held three times per week. Forty-one participants completed the entire intervention and assessments, including twenty-six that completed the neuroimaging portion. Twenty-eight age and gender matched healthy controls were recruited as a baseline comparison for neuroimaging. RESULTS: Exclusion, consented, and retention rates were; 22.7, 57.6 and 93.2% respectively. Significant (p < .05) improvements in aerobic fitness (p < .0001) were achieved over the course of the intervention. Likewise, reductions in anxiety (p = .024), depression (p = .012), and general prodromal symptoms (p < .0001) occurred, however distress did not diminish (p= .131). Right whole (p < .001) and right anterior (p = .001) hippocampal volumes significantly increased. Forward Span (p = .552), Backward Span (p = 1.000) and Letter Number Span (p = .606) did not significantly change. CONCLUSION: Aerobic exercise is a feasible and sound intervention strategy for reducing symptoms and improving overall physical health, including brain health, in youth at risk for SMI. Further research is required to replicate these findings and to expand knowledge of the mechanisms, optimum dose and factors that influence the efficacy of exercise.
- ItemOpen AccessAdolescent substance use in first episode psychosis: a test of three models(2004) Pencer, Alissa; Addington, Jean; Konnert, Candace A.
- ItemOpen AccessAn Epidemiological Study on Risk Factors for the Development of Serious Mental Illness In At-Risk Youth(2023-08) Jalali, Sara; Addington, Jean; Patten, Scott B.; Wang, JianLiUsually, mental illnesses begin in adolescence and early adulthood, and for many, persist over time. Consequently, mental illnesses lead to significant personal and societal burden. In response, there has been increasing effort in early intervention strategies that may help with delaying or stopping the progression of a mental illness to a more serious state. Aside from finding early intervention strategies best suited for young people, it is imperative to understand the psychosocial, biological and environmental factors that may lead to the development of a mental illness. Research on these early factors in youth mental illness development is limited. The aim of this study was to determine which clinical factors might be related to the development of a serious mental illness (SMI) in at-risk youth. A total of 162 participants aged 12-26 years and at various stages of risk for SMI were included in the study. Out of these participants, 31 developed a SMI. Comparisons were made on a range of baseline clinical and functional measures between two groups; those that made a transition to a SMI (n=31) and those that did not (n=131). A cox regression analysis was used to assess the relationship between measures and SMI development. Female sex, attenuated psychotic symptoms as assessed with the Scale of Psychosis-risk Symptoms (SOPS), and higher ratings on the K-10 Distress Scale were found to be significantly related to later transition to a SMI. Female participants were 2.77 times more likely to transition to SMI compared to the males. There was a 14% increased risk of transition with each one-point increase in the SOPS, and a 7% increase with a one-point increase in the K-10 scale. Results from this longitudinal study may help improve understanding of illness trajectory and aid with early detection in mental illnesses.
- ItemOpen AccessBiofeedback to Treat Anxiety in Young People at Clinical High Risk for Developing Psychosis(2016-01-18) McAusland, Laina; Addington, Jean; Raedler, Thomas; Wilkes, ChrisAnxiety is a common presenting concern for individuals at clinical high risk (CHR) for psychosis and one treatment that may be effective for anxiety is heart rate variability (HRV) biofeedback. The aim of this study was to test the efficacy of HRV biofeedback in reducing anxiety and distress in those at CHR. Twenty participants who met minimum scores for anxiety and distress completed four weeks of a HRV biofeedback intervention and received pre and post intervention assessments. There was a significant decrease in presentation of dysphoric mood and impaired ability to tolerate normal stressors. There was no change on self-report measures of anxiety and distress. Feedback and adherence were generally good. HRV biofeedback may be a feasible treatment option for individuals at CHR who have concerns with impaired stress tolerance and dysphoric mood. Future studies with a randomized controlled trial design will be necessary to further determine efficacy.
- ItemOpen AccessBrain connectomes in youth at risk for serious mental illness: an exploratory analysis(2022-09-15) Metzak, Paul D.; Shakeel, Mohammed K.; Long, Xiangyu; Lasby, Mike; Souza, Roberto; Bray, Signe; Goldstein, Benjamin I.; MacQueen, Glenda; Wang, JianLi; Kennedy, Sidney H.; Addington, Jean; Lebel, CatherineAbstract Background Identifying early biomarkers of serious mental illness (SMI)—such as changes in brain structure and function—can aid in early diagnosis and treatment. Whole brain structural and functional connectomes were investigated in youth at risk for SMI. Methods Participants were classified as healthy controls (HC; n = 33), familial risk for serious mental illness (stage 0; n = 31), mild symptoms (stage 1a; n = 37), attenuated syndromes (stage 1b; n = 61), or discrete disorder (transition; n = 9) based on clinical assessments. Imaging data was collected from two sites. Graph-theory based analysis was performed on the connectivity matrix constructed from whole-brain white matter fibers derived from constrained spherical deconvolution of the diffusion tensor imaging (DTI) scans, and from the correlations between brain regions measured with resting state functional magnetic resonance imaging (fMRI) data. Results Linear mixed effects analysis and analysis of covariance revealed no significant differences between groups in global or nodal metrics after correction for multiple comparisons. A follow up machine learning analysis broadly supported the findings. Several non-overlapping frontal and temporal network differences were identified in the structural and functional connectomes before corrections. Conclusions Results suggest significant brain connectome changes in youth at transdiagnostic risk may not be evident before illness onset.
- ItemOpen AccessExploring Neurocognition and Functional Outcome in Youth at Risk of Serious Mental Illness(2018-04-20) Romanowska, Sylvia; Addington, Jean; MacQueen, Glenda; Piskulic, DanijelaThere is a growing literature that suggests impairments in neurocognitive, social, and role functioning may be markers of susceptibility for serious mental illness development. This study assessed neurocognitive performance and social and role functioning in a sample of youth at risk of serious mental illness across different clinical stages as described by McGorry and colleagues and compared them to healthy controls. The sample consisted of 243 male and female youths aged 12-26 and included: non-help-seeking asymptomatic participants with risk factors (Stage 0; n=41); youth with early mood or anxiety symptoms and distress (Stage 1a; n=52); youth with attenuated psychiatric syndromes (Stage 1b; n=108); and healthy controls (n=42). Each participant underwent a comprehensive clinical and neurocognitive assessment. Subjects in Stage 1b had lower scores than healthy controls across all IQ measures, on the composite score of neurocognitive performance, in the domains of processing speed, working memory, attention/vigilance and reasoning and problem solving and on the social and role functioning measures. Subjects in Stage 1b also had lower scores than subjects in Stage 0 across most IQ measures, on the composite score of neurocognitive performance, in the domains of processing speed, working memory, and social cognition and on the social and role functioning measures. This study demonstrates that impairments in neurocognitive performance and social and role functioning can be present in young people experiencing subthreshold psychiatric symptoms and distress in the absence of a diagnosable mental illness. Further, it offers validation to the clinical staging model in that individuals in the higher stages of risk exhibit poorer functioning.
- ItemOpen AccessFamily history of psychosis, social risk factors and the psychosis risk syndrome(2012-09-13) Stowkowy, Jacqueline; Addington, JeanThe goal of this thesis was to determine whether individuals with a family history of psychosis who met established criteria for being at risk of developing a psychotic disorder, i.e. met criteria for a psychosis risk syndrome (FHR-COPS), differed in terms of social risk factors from individuals with a family history of psychosis who did not meet criteria for a psychosis risk syndrome (FHR-Non). Results were that FHR-COPS individuals began smoking cannabis at an earlier age, had a lower IQ, and evidenced more anxiety, increased negative schemas about the self and poorer functioning. Onset of cannabis use at an earlier age was the one significant factor that determined belonging to the FHR-COPS group. These preliminary results are promising in determining potential risk factors for the development of psychosis in those who are already at risk for psychosis on the basis of a family history.
- ItemOpen AccessNegative Symptoms in Youth at Risk of Psychosis(2020-07-02) Devoe, Daniel John Alexander; Addington, Jean; Dimitropoulos, Gina; Granholm, Eric L.; Patten, Scott B.Youth at clinical high risk (CHR) for psychosis often demonstrate significant negative symptoms but the impact of treatment on negative symptoms remains unknown. Investigations into possible mechanisms that may contribute to the development, maintenance, and exacerbation of negative symptoms in CHR youth are needed as well. One such area that remains understudied is persistent negative symptoms (PNS) in those at CHR . In addition, functioning, neurocognition, defeatist beliefs, self-efficacy, and early maladaptive schemas have been shown to contribute to negative symptoms in schizophrenia but these associations with negative symptoms remain understudied in CHR for psychosis youth. In this manuscript based thesis we conducted a systematic review and network meta-analysis of all intervention studies examining negative symptom outcomes in youth at CHR for psychosis. Next, in a large longitudinal cohort generalized linear mixed models for repeated measures were used to examine changes over time between a PNS group vs a non-PNS group on functioning, neurocognition, and defeatist beliefs. In the third study, we conducted a systematic review and meta-analysis to summarize the relationship between negative symptoms and functioning in CHR samples. In the final study, the aim was to examine if negative symptoms were associated with defeatist beliefs, self-efficacy, and early maladaptive schemas in CHR youth. In the network meta-analysis no treatments were found to significantly reduce negative symptoms and the majority of treatment trials were not designed to target negative symptoms. In the longitudinal cohort, PNS resulted in significant and persistent functional impairment, which remained when controlling for persistent depressive symptoms. For the systematic review and meta-analysis, negative symptom total scores were significantly associated with poorer global functioning, social functioning, and role functioning. In the final study, asocial beliefs, social self-efficacy and maladaptive schemas about the self were significantly related to total negative symptom scores. With no treatments established to help negative symptoms and given their significant relationship with functional impairments, an unfortunate trajectory emerges for CHR youth with negative symptoms in that they require treatments that may alleviate their symptoms and improve their day to day lives. Thus, psychosocial interventions may wish to target asocial beliefs, social self-efficacy, and maladaptive schemas in effort to reduce negative symptoms in those at CHR for psychosis.
- ItemOpen AccessNeurocognitive functioning in schizophrenia(1997) Gasbarre, Lisa Maria; Addington, Jean
- ItemOpen AccessResting State Functional Connectivity in People at Clinical High Risk for Psychosis(2013-07-15) Abraham, Nachum; Addington, JeanNeuroimaging studies in participants at clinical high risk (CHR) for psychosis may provide evidence into the etiology of psychosis. Abnormalities in connectivity have been reported in schizophrenia but little is known about resting state functional connectivity (RSFC) prior to the onset of psychosis. The aim of this project was to identify functional neuroimaging markers for individuals at CHR. It was hypothesized that each network investigated, including the default mode, salience, executive control and dorsal attention network, would show aberrant connectivity in the CHR sample. Thirty-one CHR participants who met Criteria of Prodromal Syndromes and 12 healthy controls (HC) were scanned using resting-state fMRI. Seed‐based region-of‐interest correlation analysis was used to identify the default mode, salience, executive control, and dorsal attention networks. Compared to HC, people at CHR demonstrated aberrancies in all four resting state networks that were tested. Results indicated resting state networks have altered patterns of connectivity in people at CHR for psychosis, when compared to HC. Each network tested was differentially affected. Aberrancies in RSFC suggest that functional specialization is altered in individuals at CHR who, in turn, may have difficulty properly allocating attentional resources between internal and external stimuli, even prior to the onset of psychosis.
- ItemOpen AccessSocial functioning in first- and multi-episode schizophrenia(1999) Grant, Christina Lin; Addington, Jean
- ItemOpen AccessStructural and Functional Alterations of the Brain’s Deep Grey Matter in Patients with Primary Biliary Cholangitis(2018-01-04) Mosher, Victoria; Goodyear, Bradley; MacQueen, Glenda; Swain, Mark; Dunn, Jeffrey; Addington, JeanPrimary biliary cholangitis (PBC) is an autoimmune liver disease that results in the destruction of the intrahepatic bile ducts. If left untreated, PBC can progress to liver failure or death within 10-20 years. Treatment with ursodeoxycholic acid (UDCA) can delay disease progression, but it does not work in approximately one third of patients, and it has no impact on behavioural symptoms commonly reported by PBC patients, including itch, mood disturbances, fatigue and cognitive deficits. Despite the negative impact these symptoms have on quality of life and survival, little is known about how (or even if) symptoms may impact the brain. In this thesis, we used a selection of structural and functional magnetic resonance imaging techniques to determine the impact of PBC on the brain's deep grey matter regions. We found that the functional connections between deep grey matter regions and higher-order cognitive brain regions were increased in strength, suggesting that brain networks compensate in order to maintain homeostasis in response to the immune insult from the liver. Decreased volume was observed for the thalamus, the hippocampus and a number of hippocampal subfields. In addition, regions of the brain involved in interoception showed evidence of neuroinflammation in relation to disease and symptom severity. These structural findings suggest that some brain changes observed in PBC patients may be irreversible. For most of our findings, a complete clinical response to UDCA did not impact the functional or structural brain alterations observed, suggesting these changes may occur early on in disease progression. Overall, our findings suggest early intervention may be needed to halt changes in the brain resulting from immune-mediated insults The studies within this thesis provide a base of knowledge for how behavioural symptoms may impact the brain and offer suggestions on how future research can build upon these findings.
- ItemOpen AccessThe association between social anxiety and social functioning in first episode psychosis(2005) Voges, Marcia A.; Addington, Jean; Hodgins, David C.
- ItemOpen AccessThe course of cognitive functioning in individuals at clinical risk for psychosis(2011) Colijn, Mark Ainsley; Addington, Jean
- ItemOpen AccessThe psychological well-being of family members of individuals with schizophrenia(1998) Martens, Laurie; Addington, Jean
- ItemEmbargoWorking Memory and Processing Speed Training in Schizophrenia: A Randomized Controlled Trial(2018-06-11) Cassetta, Briana Diane; Tomfohr-Madsen, Lianne M.; Addington, Jean; Goldberg, Joel; Sears, Christopher R.; Ewashen, Carol J.Individuals with schizophrenia are generally found to experience cognitive deficits in most domains of cognition. Moreover, greater cognitive deficits have been associated with poorer daily functioning in schizophrenia. Given these findings, cognitive training has been a burgeoning area of research in recent years, with some evidence suggesting that cognitive training programs may improve cognition for individuals with schizophrenia. However, the state of the literature remains unclear as to which domains of cognition should be targeted to produce the most widespread benefits for individuals with schizophrenia. One suggestion is that targeting lower-level cognitive processes that are important for higher-level and more complex aspects of cognition may produce the most widespread and durable benefits in cognition and everyday functioning. In particular, working memory (WM) and processing speed (PS) have been named as two key areas of deficit in schizophrenia, and two domains of cognition that may be linked to higher-order cognition and daily functioning. This study aimed to investigate the near-transfer (transfer of gains to related contexts), far-transfer (transfer of gains to unrelated contexts), and real-world gains associated with WM and PS training in schizophrenia. To this end, 83 participants with schizophrenia or schizoaffective disorder were recruited and randomly assigned to computerized WM training, PS training, or a no-training control group. Results showed that PS training led to significant gains in untrained PS tasks as well as gains in far-transfer tasks that required speed of processing, relative to the other groups. WM training did not lead to gains in untrained WM tasks, and showed inconsistent effects on some far-transfer tasks. These results suggest that there can be benefits of domain-specific cognitive training, specifically PS training, in schizophrenia. Far-transfer of gains to other cognitive domains and to real-world functioning may not occur after targeted WM or PS training, though non-specific effects (e.g., through behavioural activation, increased motivation) may lead to improvements on some cognitive tasks. Future studies should continue to investigate the mechanisms by which cognitive training may lead to enhancements in cognition and functioning in schizophrenia.
- ItemOpen AccessYouth at-risk for serious mental illness: methods of the PROCAN study(2018-07-05) Addington, Jean; Goldstein, Benjamin I; Wang, Jian L; Kennedy, Sidney H; Bray, Signe; Lebel, Catherine; Hassel, Stefanie; Marshall, Catherine; MacQueen, GlendaAbstract Background Most mental disorders begin in adolescence; however, there are gaps in our understanding of youth mental health. Clinical and policy gaps arise from our current inability to predict, from amongst all youth who experience mild behavioural disturbances, who will go on to develop a mental illness, what that illness will be, and what can be done to change its course and prevent its worsening to a serious mental illness (SMI). There are also gaps in our understanding of how known risk factors set off neurobiological changes that may play a role in determining who will develop a SMI. Project goals are (i) to identify youth at different stages of risk of SMI so that intervention can begin as soon as possible and (ii) to understand the triggers of these mental illnesses. Method This 2-site longitudinal study will recruit 240 youth, ages 12–25, who are at different stages of risk for developing a SMI. The sample includes (a) healthy individuals, (b) symptom-free individuals who have a first-degree relative with a SMI, (c) youth who are experiencing distress and may have mild symptoms of anxiety or depression, and (d) youth who are already demonstrating attenuated symptoms of SMI such as bipolar disorder or psychosis. We will assess, every 6 months for one year, a wide range of clinical and psychosocial factors to determine which factors can be used to predict key outcomes. We will also assess neuroimaging and peripheral markers. We will develop and validate a prediction algorithm that includes demographic, clinical and psychosocial predictors. We will also determine if adding biological markers to our algorithm improves prediction. Discussion Outcomes from this study include an improved clinical staging model for SMI and prediction algorithms that can be used by health care providers as decision-support tools in their practices. Secondly, we may have a greater understanding of clinical, social and cognitive factors associated with the clinical stages of development of a SMI, as well as new insights from neuroimaging and later neurochemical biomarker studies regarding predisposition to SMI development and progression through the clinical stages of illness.