Kathryn Baker

Psychotic-like experiences in a community sample of adolescents: implications for the continuum model of psychosis and prediction of schizophrenia

Objective: Studies conducted in community samples suggest that psychotic-like experiences are common in the general population, leading to suggestions that they are either variations of normal personality or are different expressions of underlying vulnerability to psychotic disorder. Different types of psychotic symptoms may exist, some being normal variants and some having implications for mental health and functioning. The aim of the present study was to determine if different subtypes of psychotic-like experiences could be identified in a community sample of adolescents and to investigate if particular subtypes were more likely to be associated with psychosocial difficulties, that is, distress, depression and poor functioning, than other subtypes. Method: Eight hundred and seventy-five Year 10 students from 34 schools participated in a cross-sectional survey that measured psychotic-like experiences using the Community Assessment of Psychic Experiences; depression using the Centre for Epidemiologic Studies Depression Scale; and psychosocial functioning using the Revised Multidimensional Assessment of Functioning Scale. Factor analysis was conducted to identify any subtypes of psychotic experiences. Results: Four subtypes of psychotic-like experiences were identified: Bizarre Experiences, Perceptual Abnormalities, Persecutory Ideas, and Magical Thinking. Intermittent, infrequent psychotic experiences were common, but frequent experiences were not. Bizarre Experiences, Perceptual Abnormalities and Persecutory Ideas were strongly associated with distress, depression and poor functioning. Magical Thinking was only weakly associated with these variables. Overall these findings may suggest that infrequent psychotic-like experiences are unlikely to be a specific risk factor for onset of a psychotic disorder in community samples. Conclusions: Given that the different subtypes had varying associations with current difficulties it is suggested that not all subtypes confer the same risk for onset of psychotic disorder and poor outcome. Bizarre Experiences, Perceptual Abnormalities and Persecutory Ideas may represent expressions of underlying vulnerability to psychotic disorder, but Magical Thinking may be a normal personality variant.

Association between psychotic experiences and depression in a clinical sample over 6 months.

Psychotic-like experiences (PLEs) are used to identify individuals considered to be at Ultra High Risk (UHR) of, or prodromal for, psychotic disorder. They are also common in the general population and in clinical samples of non-psychotic individuals. Depression has been found to be an important factor in mediating outcome in those with PLEs in both community and UHR populations. It is associated with increased risk of transition to psychotic disorder in the UHR group, and with need for care in relation to PLEs in community samples. In this study we aimed to examine the 6-month outcome of PLEs in a sample of help-seeking young people aged 15 to 24 years in relation to their level of depression. Subjects (n=140) were assessed at baseline and 6 months for PLEs and depression. PLEs were measured by the Community Assessment of Psychic Experiences (CAPE). Depression was assessed as a continuous measure using the Mood and Anxiety Symptom Questionnaire (MASQ) and categorically according to DSM-IV diagnosis of mood disorder. PLEs reduced in conjunction with an improvement in depression level and with remission of diagnosis of mood disorder. It is important to assess depression in those with PLEs and consider the need for treatment of the comorbid depressive syndrome. This may reduce the risk of worsening of PLEs and transition to psychotic disorder.

Randomized controlled trial of interventions for young people at ultra-high risk of psychosis: study design and baseline characteristics

Objective: Intervention during the pre-psychotic period of illness holds the potential of delaying or even preventing the onset of a full-threshold disorder, or at least of reducing the impact of such a disorder if it does develop. The first step in realizing this aim was achieved more than 10 years ago with the development and validation of criteria for the identification of young people at ultra-high risk (UHR) of psychosis. Results of three clinical trials have been published that provide mixed support for the effectiveness of psychological and pharmacological interventions in preventing the onset of psychotic disorder. Method: The present paper describes a fourth study that has now been undertaken in which young people who met UHR criteria were randomized to one of three treatment groups: cognitive therapy plus risperidone (CogTher + Risp: n = 43); cognitive therapy plus placebo (CogTher + Placebo: n = 44); and supportive counselling + placebo (Supp + Placebo; n = 28). A fourth group of young people who did not agree to randomization were also followed up (monitoring: n = 78). Baseline characteristics of participants are provided. Results and conclusion: The present study improves on the previous studies because treatment was provided for 12 months and the independent contributions of psychological and pharmacological treatments in preventing transition to psychosis in the UHR cohort and on levels of psychopathology and functioning can be directly compared. Issues associated with recruitment and randomization are discussed.

Validity of the 12-item General Health Questionnaire (GHQ-12) in detecting depressive and anxiety disorders among high school students.

Despite the common use of the 12-item General Health Questionnaire (GHQ-12) with adolescents, there is limited data supporting its validity with this population. The aims of the study were to investigate the psychometric properties of the GHQ-12 among high school students, to validate the GHQ-12 against the gold standard of a diagnostic interview, and to suggest a threshold score for detecting depressive and anxiety disorders. Six hundred and fifty-four high school students from years 10 to 12 (ages 15-18) completed the GHQ-12 (Likert scored) and the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-IV-Test Revision (DSM-IV-TR). Receiver operating characteristic (ROC) curves were plotted. The mean GHQ-12 score for the total sample was 9.9 (S.D.=5.4). Results from the ROC curve indicated that the GHQ-12 performed better than chance at identifying depressive and anxiety disorders (area under the curve (AUC)=0.781). A GHQ-12 threshold score of 9/10 for males and 10/11 for females was found to be optimal. Given the significant proportion of mental illness among high school students, there may be a need to introduce screening for mental illnesses as part of the school curriculum. This can assist with the early identification and enable low stigma preventive intervention within the school environment.

The association between early cannabis use and psychotic-like experiences in a community adolescent sample

Cannabis use has been associated with greater risk of developing psychotic-like experiences (PLEs) and psychosis. This paper aims to determine if different levels of cannabis (lifetime, regular, recent) exposure are associated with PLEs and specific PLE subscales among adolescents. Participants consisted of a community sample of 880 adolescents in Melbourne, Australia. Adolescents were administered the positive symptom scale of the Community Assessment of Psychic Experiences (CAPE) and measures of substance use and depression. Lifetime cannabis use and the frequency of cannabis use in the last year (recent use) were associated with PLEs, primarily the experience of auditory and visual hallucinations (perceptual abnormalities). Low levels of recent cannabis use were more strongly associated with PLEs than more frequent use. These findings indicate that different levels of cannabis exposure were differentially associated with PLEs and highlight the need for early detection and treatment strategies for PLEs and cannabis use in adolescents.

Impact of co-occurring substance use on 6 month outcomes for young people seeking mental health treatment.

Objective: Co-occurring substance use and mental health disorders are highly prevalent among young people attending services, yet few studies have examined the effect of such comorbidity among those referred for treatment. The aim of the current study was to examine the impact of co-occurring substance use disorders (SUDs) on 6 month outcomes for young people seeking mental health treatment. Method: One hundred and six young people (aged 15–24 years) with a non-psychotic DSM-IV Axis I disorder were assessed following referral to a specialist youth public mental health service. Participants were given a structured interview, as well as questionnaires assessing drug use, psychopathology, psychosocial functioning and self-esteem at baseline and 6 month follow up. Results: At baseline, 23 participants met criteria for a co-occurring SUD and 83 had a non-psychotic Axis I disorder. Both the non-SUD and the co-occurring SUD groups had high levels of psychopathology, serious impairments in functioning and moderate levels of suicidal ideation, although those with co-occurring SUD had significantly poorer levels of functioning. At 6 month follow up the co-occurring SUD group continued to experience substantial problems with symptoms and functioning whereas the non-SUD group had significant improvement in both of these domains. Conclusions: The present findings are consistent with studies examining the impact of co-occurring substance use and mental health issues across different treatment settings, and reinforce recommendations that young people with co-occurring disorders require more intensive and integrated interventions. The present findings also highlight the need for routine assessment and management of substance use issues within youth mental health settings.

Can receipt of a regular postcard reduce suicide‐related behaviour in young help seekers? A randomized controlled trial

Aim: Suicide attempt, ideation and deliberate self‐harm are common among adolescents. Limited evidence exists regarding interventions that can reduce risk; however, research indicates that maintaining contact with at‐risk adults following discharge from services via letter or postcard can reduce risk. The aim of the study was to test a postcard intervention among people aged 15–24 who presented to mental health services but were not accepted, yet were at risk of suicide.

Outcome of Suicidal Ideation and Behavior in a Young, Help-Seeking Population over a 2-Year Period

Suicidal behavior is associated with negative outcomes, including completed suicide. This study examined the prevalence of suicidal behavior in a sample of referrals to a youth psychiatric service and investigated the stability of suicidality over 2 years. Of the 140 people (mean age 17.8) who were referred to a youth psychiatric service, 82 who were accepted for treatment (RA group) and 58 who were not accepted (RNA group) were assessed; 57% reported considering suicide and 39% reported attempting suicide in the 12 months prior to referral. Participants who reported suicidal ideation were significantly more likely than nonsuicidal participants to have multiple Axis I diagnoses and lower levels of functioning. At the 2-year follow-up there was a significant reduction in suicidality in the RA group, but not in the RNA group. In conclusion, suicidality is prevalent among young people referred to psychiatric services. Even brief contact with services results in a reduction in suicidality over 2 years.