A longitudinal study of neurocognitive function in individuals at-risk for psychosis

INTRODUCTION: Clinically defined prodromal diagnostic criteria identify at-risk individuals with a 35-40% likelihood of developing a psychotic disorder within a year. The time course and predictive value of cognitive deficits in the development of psychosis has not been established. METHODS: A comprehensive neurocognitive battery and clinical assessments were administered to 37 subjects meeting Criteria of Prodromal States (COPS) criteria for being at risk for psychosis, and two comparison groups: 59 first episode and 47 healthy subjects. Subjects were also evaluated at 6-month and 1-year follow-up periods. Primary analyses used a neurocognitive composite score derived from individual neurocognitive measures, including measures of vigilance, verbal memory, working memory, and processing speed. RESULTS: At-risk subjects performed more poorly than healthy subjects (t=2.93, P=0.01), but better than first episode subjects (t=4.72, p<0.0001). At-risk subjects were particularly impaired on measures of vigilance and processing speed. Cognitive composite scores were significantly lower in at-risk subjects who progressed to psychosis (N=11; z=-1.2), while those at-risk subjects who did not progress to psychosis (N=17) performed better (z=-0.5), and not significantly different from controls. Poor CPT performance combined with better WAIS-R digit symbol performance predicted progression to psychosis. Severity of neurocognitive deficits was not related to duration of prodrome or to time to development of psychosis and neurocognitive function improved in all subjects except those who progressed to psychosis. CONCLUSION: Neurocognitive impairment emerges early in the course of psychotic illness. Performance on tests of neurocognition may prove to be an early risk predictor for subsequent development of psychotic disorders.     

The risk and associated factors of methamphetamine psychosis in methamphetamine-dependent patients in Malaysia

ObjectiveThe objective of this study was to determine the risk of lifetime and current methamphetamine-induced psychosis in patients with methamphetamine dependence. The association between psychiatric co-morbidity and methamphetamine-induced psychosis was also studied.MethodsThis was a cross-sectional study conducted concurrently at a teaching hospital and a drug rehabilitation center in Malaysia. Patients with the diagnosis of methamphetamine based on DSM-IV were interviewed using the Mini International Neuropsychiatric Interview (M.I.N.I.) for methamphetamine-induced psychosis and other Axis I psychiatric disorders. The information on sociodemographic background and drug use history was obtained from interview or medical records.ResultsOf 292 subjects, 47.9% of the subjects had a past history of psychotic symptoms and 13.0% of the patients were having current psychotic symptoms. Co-morbid major depressive disorder (OR = 7.18, 95 CI = 2.612–19.708), bipolar disorder (OR = 13.807, 95 CI = 5.194–36.706), antisocial personality disorder (OR = 12.619, 95 CI = 6.702–23.759) and heavy methamphetamine uses were significantly associated with lifetime methamphetamine-induced psychosis after adjusted for other factors. Major depressive disorder (OR = 2.870, CI = 1.154–7.142) and antisocial personality disorder (OR = 3.299, 95 CI = 1.375–7.914) were the only factors associated with current psychosis.ConclusionThere was a high risk of psychosis in patients with methamphetamine dependence. It was associated with co-morbid affective disorder, antisocial personality, and heavy methamphetamine use. It is recommended that all cases of methamphetamine dependence should be screened for psychotic symptoms.     

An initial investigation of abnormal bodily phenomena in subjects at ultra high risk for psychosis: Their prevalence and clinical implications

BackgroundContemporary phenomenological research has considered abnormal bodily phenomena (ABP) to be a phenotypic trait of subjects with schizophrenia in their first psychotic episode. Yet the prevalence of ABP and their clinical significance in subjects at Ultra High Risk (UHR) of psychosis remain unidentified. This study is an exploratory investigation of ABP in UHR subjects and matched healthy controls (HCs) examining their relation to clinical features and basic self-disturbances.MethodsA sample of 26 UHR and 14 HC subjects from three prodromal and early intervention clinics in South London, West London and Cambridge was assessed with the Abnormal Bodily Phenomena questionnaire (ABPq), Comprehensive Assessment of At-Risk Mental States (CAARMS), the Positive and Negative Syndrome Scale (PANSS), the Social and Occupational Functioning Assessment Scale (SOFAS) and the Examination of Anomalous Self Experiences (EASE) checklist.ResultsIn our sample ABP occurred in 73.1% of UHR subjects and prominent ABP (proABP) were referred in 53.8% of them. No HC subject reported ABP. The UHR group with proABP had lower CAARMS total score (t = − 9.265, p = 0.006). There were no differences in PANSS total score (t = − 1.235, p = 0.277), SOFAS score (H(2) 22.27, p = 0.666) and EASE total scores (z = 8.565, adjusted p = 0.185) in the UHR subjects with prominent ABP versus those that did not.DiscussionThis initial investigation suggests that ABP could be a prevalent phenotypic feature of UHR subjects.     

Verbal fluency as a possible predictor for psychosis

BackgroundNeurocognitive abnormalities are prevalent in both first episode schizophrenia patients and in ultra high risk (UHR) patients.AimTo compare verbal fluency performance at baseline in UHR in patients that did and did not make the transition to psychosis.MethodBaseline verbal fluency performance in UHR-patients (n = 47) was compared to match first episode patients (n = 69) and normal controls (n = 42).ResultsVerbal fluency (semantic category) scores in UHR-patients did not differ significantly from the score in first episode schizophrenia patients. Both the UHR group (p < 0.003) and the patient group (p < 0.0001) performed significantly worse than controls. Compared to the non-transition group, the transition group performed worse on verbal fluency, semantic category (p < 0.006) at baseline.ConclusionsVerbal fluency (semantic category) is disturbed in UHR-patients that make the transition to psychosis and could contribute to an improved prediction of transition to psychosis in UHR-patients.     

Difficulty in making contact with others and social withdrawal as early signs of psychosis in adolescents – the Northern Finland Birth Cohort 1986

AimSocial withdrawal is among the first signs of the prodromal state of psychosis seen in clinical samples. The aim of this prospective study was to find out whether difficulty in making contact with others and social withdrawal precede first episode psychosis in the young general population.MethodsThe members of the Northern Finland Birth Cohort 1986 (n = 6274) completed the PROD-screen questionnaire in 2001–2002. The Finnish Hospital Discharge Register was used to detect both new psychotic and non-psychotic disorders requiring hospitalisation during 2003–2008.ResultsTwenty-three subjects developed psychosis and 89 developed a non-psychotic mental disorder requiring hospitalisation during the follow-up. Of those who developed psychosis, 35% had reported difficulty or uncertainty in making contact with others and 30% social withdrawal in adolescence. In hospitalised non-psychotic disorder, the corresponding precentages were 10 and 13% and in the control group without hospital-treated mental disorder 9 and 11%. The differences between psychotic and non-psychotic hospitalised subjects (P < 0.01) as well as controls (P < 0.001) were statistically significant regarding difficulty or uncertainty in making contact with others.ConclusionsIn this general population-based sample self-reported difficulty or uncertainty in making contact with others in adolescence preceded psychosis specifically compared to hospitalised non-psychotic mental disorders and controls.     

Attention,vigilance and visuospatial function in hospitalized elderly medical patients: Relationship to neurocognitive diagnosis

ObjectiveEfficient detection of neurocognitive disorders is a key diagnostic challenge. We explored how simple bedside tests of attention, vigilance and visuospatial function might assist in identifying delirium in hospitalized patients.MethodsPerformance on a battery of bedside cognitive tests was compared in elderly medical inpatients with DSM-IV delirium, dementia, comorbid delirium-dementia, and no neurocognitive disorder.Results193 patients [mean age 79.9 ± 7.3; 97 male] were assessed with delirium (n = 45), dementia (n = 33), comorbid delirium-dementia (n = 65) and no neurocognitive disorder (NNCD) (n = 50). The ability to meaningfully engage with the tests varied from 84% (Spatial Span Forwards) to 57% (Vigilance B test), and was especially problematic among the comorbid delirium-dementia group. The NNCD was distinguished from the delirium groups for most tests, and from the dementia group for the Vigilance B test and the Clock Drawing Test. The dementia group differed from delirium groups in respect of the Months Backward Test, Vigilance A and B tests, Global assessment of visuospatial ability and the Interlocking Pentagons Test. Overall, patients with delirium were best identified by three tests – the Months Backward Test, Vigilance A test and the Global Assessment of visuospatial function with failure to correctly complete any two of these predicting delirium status in 80% of cases.ConclusionSimple bedside tests of attention, vigilance and visuospatial ability can help to distinguish neurocognitive disorders, including delirium, from other presentations. There is a need to develop more accurate methods specifically designed to assess patients with neurocognitive disorder who are unable to engage with conventional tests.     

Évaluation des états mentaux à risque de transition psychotique dans un échantillon de jeunes détenus de sexe masculin en Tunisie

BackgroundPrevalence of psychotic disorders in a prison population is higher than in the general population. Recent research has shown that early intervention is feasible in prison settings, and that approximately 5% of screened prisoners have met ultra-high-risk (UHR) for psychosis criteria. We aimed to identify the prevalence of the UHR states for developing psychosis in a group of newly incarcerated men in the Jendouba Civil Prison and to analyze the association between UHR states and socio-demographic data and substance use.MethodWe carried-out a cross-sectional study among 120 prisoners. Every prisoner was interviewed using the Comprehensive Assessment of At-Risk Mental States (CAARMS). The Social and Occupational Functioning Assessment Scale (SOFAS) was used to assess the participant's level of functioning.ResultsWe found a prevalence of subjects meeting the UHR criteria of 21.3%. UHR subjects had significantly more psychiatric family history (P = 0.035), personal history of suicide attempt(s) (0.035) and self-injury (P = 0.013) compared to non-UHR subjects. Clinical self-evaluation found significantly more depression and anxiety in the UHR group (P = 0.020 and P = 0.035, respectively). In addition, social and occupational functioning was significantly more impaired in the UHR group (P = 0.007). UHR subjects used significantly more cannabis in lifetime (P = 0.015) as well as in the past year (P = 0.022) and had a significantly higher frequency of cannabis use (P = 0.01) compared to non-UHRs.ConclusionPrison mental health teams face the challenge of identifying prisoners who need mental health services and providing early care to this vulnerable group; this challenge may offer a unique opportunity for intervention among a population that might not otherwise have had access to it.     

TCF4 gene polymorphism and cognitive performance in patients with first episode psychosis

BackgroundSingle nucleotide polymorphisms in TCF4 gene have been consistently associated with schizophrenia in genome wide association studies, including the C allele of rs9960767. However, its exact role in modulating the schizophrenia phenotype is not known.AimsTo comprehensively investigate the relationship between rs9960767 risk allele (C) of TCF4 and cognitive performance in patients with first episode psychosis (FEP).Methods173 patients with FEP received a comprehensive neurocognitive evaluation and were genotyped for rs9960767. Carriers of the risk allele (CA/CC) were compared to non-carriers (AA) using Multivariate Analysis of Covariance MANCOVA. Ethnicity, negative symptoms and substance abuse were included as covariates.ResultsCarriers of the risk allele had a statistically significant lower performance in the cognitive domain of Reasoning/Problem-Solving compared to non-carriers (F_1,172 = 4.4, p = .038). There were no significant genotype effects on the other cognitive domains or general cognition. This effect on the Reasoning/Problem-Solving domain remained significant even when controlling for IQ (F_1,172 = 4.3, p = .039).Conclusionsrs9960767 (C) of TCF4 appears to be associated with neurocognitive deficits in the Reasoning/Problem-Solving cognitive domain, in patients with FEP. A confirmation of this finding in a larger sample and including other TCF4 polymorphisms will be needed to gain further validity of this result.     

Reduced gray matter volume in psychotic disorder patients with a history of childhood sexual abuse

Childhood trauma is associated with smaller gray matter volume, similar to the pattern seen in psychotic disorders. We explored the relationship between childhood abuse, psychosis, and brain volume in a group of 60 individuals with a psychotic disorder and 26 healthy control subjects. We used voxel-based morphometry (VBM) to quantify gray and white matter volume and the Childhood Trauma Questionnaire (CTQ) to measure childhood abuse. Within the psychotic disorder group, total gray matter volume was inversely correlated with the severity of childhood sexual abuse (r = ? .34, p = .008), but not the other types of abuse. When the 24 patients with sexual abuse were compared with demographically matched samples of 23 patients without sexual abuse and 26 control subjects, only patients with a history of sexual abuse had reduced total gray matter volume (t(48) = 2.3, p = .03; Cohen's d = .63). Voxel-based analysis revealed a cluster in the prefrontal cortex where volume was negatively correlated with sexual abuse severity. Voxel based comparison of the three matched groups revealed a similar pattern of results, with widespread reductions in psychosis patients with sexual abuse relative to controls that were not found in psychosis patients without sexual abuse. These findings indicate that some of the variance of gray matter volume in psychotic disorders can be explained by a history of sexual abuse.     

Suicide attempt in first-episode psychosis: A 7.4 year follow-up study

BackgroundIndividuals with first-episode psychosis demonstrate high rates of suicide attempt (SA).Aims1) To examine the prevalence of, and risk factors for, SA in a first-episode psychosis (FEP) cohort over a 7.4 year follow-up period. 2) To investigate differences between single versus multiple suicide attempters.MethodsThis study reports baseline and follow-up data from a naturalistic, prospective follow-up of 413 FEP patients treated at a specialist early psychosis centre. Assessments were conducted at treatment entry, initial symptom remission or stabilization, and long term follow-up. Binary logistic regression models were used to assess unadjusted and adjusted associations between early illness and sociodemographic characteristics and two outcome measures: any SA during follow-up; and multiple SAs.ResultsFollow-up data were available for 282 participants. Sixty-one (21.6%) made a suicide attempt over the follow-up period, including 12 successful suicides. The following baseline risk factors increased the risk of any SA: history of self-harm (OR = 4.27; p < 0.001), suicidal tendencies (OR = 2.30; p = 0.022), being depressed for > 50% of the initial psychotic episode (OR = 2.49; p = 0.045), and hopelessness (OR = 2.03; p = 0.030). History of problem alcohol use increased the risk of multiple SAs (OR = 4.43; 95% CI (1.05–18.7); p = 0.043).DiscussionThe prevalence of suicide attempt in this study exceeds reports from short-term FEP studies but is comparable to longer term follow-up studies, indicating that risk remains elevated for at least 7 years following commencement of treatment. The key predictor of future suicide attempt was previous self-harm, indicating that interventions for self-harm are required.     

The validity of self-rated psychotic symptoms in depressed inpatients

BackgroundSelf-ratings of psychotic experiences might be biased by depressive symptoms.MethodData from a large naturalistic multicentre trial on depressed inpatients (n = 488) who were assessed on a biweekly basis until discharge were analyzed. Self-rated psychotic symptoms as assessed with the 90-Item Symptom Checklist (SCL-90) were correlated with the SCL-90 total score, the SCL-90 depression score, the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale 21 item (HAMD-21) total score, the Montgomery Åsberg Depression Rating Scale (MADRS) total score and the clinician-rated paranoid-hallucinatory score of the Association for Methodology and Documentation in Psychiatry (AMDP) scale.ResultsAt discharge the SCL-90 psychosis score correlated highest with the SCL-90 depression score (0.78, P < 0.001) and with the BDI total score (0.64, P < 0.001). Moderate correlations were found for the MADRS (0.34, P < 0.001), HAMD (0.37, P < 0.001) and AMDP depression score (0.33, P < 0.001). Only a weak correlation was found between the SCL-90 psychosis score and the AMDP paranoid-hallucinatory syndrome score (0.15, P < 0.001). Linear regression showed that change in self-rated psychotic symptoms over the treatment course was best explained by a change in the SCL-90 depression score (P < 0.001). The change in clinician-rated AMDP paranoid-hallucinatory score had lesser influence (P = 0.02).ConclusionsIn depressed patients self-rated psychotic symptoms correlate poorly with clinician-rated psychotic symptoms. Caution is warranted when interpreting results from epidemiological surveys using self-rated psychotic symptom questionnaires as indicators of psychotic symptoms. Depressive symptoms which are highly prevalent in the general population might influence such self-ratings.     

The impact of negative treatment experiences on persistent refusal of antipsychotics

AimsWe investigate reasons for persistent medication refusal in schizophrenia spectrum disorders and test whether factors that speak for a rational decision, such as negative experiences with medication or low symptom distress predict medication refusal, even after taking differences in insight into account.MethodWe included 45 participants with schizophrenia spectrum disorders, of which 20 had refused antipsychotic medication for at least three months and assessed reasons for taking or not taking medication, labeling condition as mental disorder (“insight"), experiences with the previous treatments, symptoms and symptom distress, positive and negative consequences and experiences of psychosis, causal beliefs, therapeutic relationships with previous clinicians and attitudes towards medication.ResultsGroups did not differ in symptom severity but medication refusers reported significantly less insight, less satisfaction with their most-recent psychiatrist and with previous medication, and more negative beliefs about harmful effects of medication. They also felt less informed about medication. After controlling for insight, the perceived helpfulness of the previous treating psychiatrist (OR = 0.30, z = 5.58, p = 0.018) and of previous medication (OR = 0.27, z = 6.87, p = 0.009) and feeling insufficiently informed about medication (OR = 0.53, z = 3. 85, p = 0.050) significantly predicted medication discontinuation.ConclusionsBuilding rapport with patients with a different view of the nature of their condition and encouraging informed decisions on medication are likely to improve medication adherence. However, the findings also suggest that refusing medication after a phase of initial adherence is also the consequence of negative experiences with medication and could result from weighing the pros against the cons.     

The effect of atypical antipsychotics on pituitary gland volume in patients with first-episode psychosis: A longitudinal MRI study

BackgroundPituitary volume is currently measured as a marker of hypothalamic-pituitary-adrenal hyperactivity in patients with psychosis despite suggestions of susceptibility to antipsychotics. Qualifying and quantifying the effect of atypical antipsychotics on the volume of the pituitary gland will determine whether this measure is valid as a future estimate of HPA-axis activation in psychotic populations.AimsTo determine the qualitative and quantitative effect of atypical antipsychotic medications on pituitary gland volume in a first-episode psychosis population.MethodPituitary volume was measured from T1-weighted magnetic resonance images in a group of 43 first-episode psychosis patients, the majority of whom were neuroleptic-naïve, at baseline and after 3 months of treatment, to determine whether change in pituitary volume was correlated with cumulative dose of atypical antipsychotic medication.ResultsThere was no significant baseline difference in pituitary volume between subjects and controls, or between neuroleptic-naïve and neuroleptic-treated subjects. Over the follow-up period there was a negative correlation between percentage change in pituitary volume and cumulative 3-month dose of atypical antipsychotic (r = ? 0.37), i.e. volume increases were associated with lower doses and volume decreases with higher doses.ConclusionsAtypical antipsychotic medications may reduce pituitary gland volume in a dose-dependent manner suggesting that atypical antipsychotic medication may support affected individuals to cope with stress associated with emerging psychotic disorders.     

Psychological interventions for adolescent psychosis: A pilot controlled trial in routine care

PurposeEvidence for the recommendation to deliver Cognitive Behavioural Therapy (CBT) and Family Interventions (FI) to under-18s with psychosis derives from adult research, and no previous study has focused exclusively on an adolescent population. We evaluated adaptations of these therapies for adolescent inpatients with psychosis (CBTpA and FIpA), delivered as an adjunct to inpatient standard care (SC).Subjects and methodsThirty adolescent inpatients with psychotic symptoms on admission were sequentially allocated to receive CBTpA + SC (n = 10); FIpA + SC (n = 10) or SC alone (n = 10). Psychotic symptoms and functioning were measured at admission and discharge.ResultsGroup comparisons did not reach conventional significance, but effect sizes in this pilot study showed a promising impact of CBTpA compared to SC alone, in reducing symptoms (ES: d = 0.6), with smaller effect sizes for functioning (d = 0.2) and for FIpA (symptoms, d = 0.1 and functioning, d = 0.4). There was no advantage of either additional treatment in reducing length of stay, but self-report satisfaction ratings were higher for both psychological therapies.Discussion and conclusionsThe study is the first to focus on an exclusively adolescent population, using appropriately adapted therapy protocols. Findings suggest that the interventions are feasible, acceptable and helpful for adolescents with psychosis. Larger randomised controlled trials are now needed.     

Impaired family functioning in psychosis and its relevance to relapse: a two-year follow-up study

BackgroundThe aim of the present study was to investigate whether dysfunctional family functioning contributes to relapse over a two-year follow-up period in patients experiencing their first episode of psychosis (FEP) and chronic patients with psychosis.MethodsThe sample consisted of 100 remitted patients (50 FEP and 50 chronic) diagnosed with schizophrenia (82%) or bipolar disorder with most recent episode manic severe with psychotic features (18%) recruited from the Inpatient Psychiatric Unit of the University Hospital of Heraklion, Crete, Greece, and their family caregivers. Family functioning was assessed in terms of cohesion and flexibility (FACES-IV), expressed emotion (FQ), family burden (FBS) and caregivers’ psychological distress (GHQ-28). Relapse was defined as patient rehospitalisation due to acute psychotic exacerbation, while number, length, and type of hospitalisations were also evaluated.ResultsDysfunctional family functioning in terms of cohesion and flexibility was not found to be a significant risk factor for relapse in psychosis. High expressed emotion, as indexed primarily by increased levels of criticism rather than emotional over-involvement, was associated with increased risk of relapse and shorter time to relapse (HR = 0.48, 95% CI: 0.24, 0.98, p = 0.043). Similarly, high levels of family burden were related to shorter time to relapse (HR = 0.47, 95% CI: 0.23, 0.95, p = 0.037), whereas there was no significant difference in survival curves based on caregivers’ psychological distress. No significant interaction effect of illness chronicity was observed in the aforementioned associations.ConclusionThese findings highlight caregivers’ criticism and burden of care as long-term predictors of the course of psychosis from the early stages of the illness and later on. In contrast, unbalanced levels of cohesion and flexibility in the family, as well as caregivers’ high emotional over-involvement and psychological distress do not appear to be factors that contribute to patient relapse. Family psychoeducational interventions focusing at ameliorating caregivers’ negativity toward the patient, and easing the burden of care should be considered as means in reducing relapse.     

Childhood adversity and psychosis: Examining whether the association is due to genetic confounding using a monozygotic twin differences approach

PurposeTo test whether the association between childhood adversity and positive and negative psychotic experiences is due to genetic confounding.MethodChildhood adversity and psychotic experiences were assessed in an ongoing sample of 226 twins from the general population. A monozygotic (MZ) twin differences approach was used to assess possible genetic confounding.ResultsIn the whole sample, childhood adversity was significantly associated with positive (β = 45; SE = 0.16; P = 0.008) and negative psychotic experiences (β = 0.77; SE = 0.18; P < 0.01). Within-pair MZ twin differences in exposure to childhood adversity were significantly associated with differences in positive (β = 71; SE = 0.29; P = 0.016) and negative psychotic experiences (β = 98; SE = 0.38; P = 0.014) in a subsample of 85 MZ twin pairs.ConclusionsIndividuals exposed to childhood adversity are more likely to report psychotic experiences. Furthermore, our findings indicate that this association is not due to genetic confounding.     

Suicidal behaviors and their relationship with psychotic-like symptoms in children and adolescents at clinical high risk for psychosis

BackgroundPrevious research has demonstrated elevated rates of suicide attempts and ideation in individuals with psychosis. This study investigated rates and severity of suicidal behavior in youth with and at clinical high risk for psychosis, and examined the positive, negative, and disorganized symptoms associated with suicidal behaviors among the clinical high risk group.MethodsEighty-six youth ages 7–18 (n = 21 non-clinical controls [NCC], n = 40 clinical high risk [CHR], n = 25 diagnosed psychotic disorder [PD]) were recruited. CHR and PD participants were identified using the Structured Interview for Prodromal Symptoms (SIPS) and Schedule for Affective Disorders and Schizophrenia for School-Age Children—Present and Lifetime Version (KSADS-PL). All participants completed the Suicide Behaviors Questionnaire-Revised (SBQ-R).ResultsFindings indicated significantly higher levels of suicidal behavior among CHR and PD relative to NCC participants (F = 7.64, p = 0.001). 17.5% of CHR participants had previously attempted suicide. Dysphoric Mood and Odd Behavior or Appearance were significantly correlated with suicidal behavior severity among CHR youth.ConclusionSuicidal behavior was observed with greater frequency and severity in the CHR and PD groups than in the NCC group. CHR suicidal behavior severity was correlated most strongly with Dysphoric Mood and Odd Behavior or Appearance, a relationship which warrants further investigation.     

Correlations between cognitive performances and psychotic or schizotypal dimensions

ObjectiveTo test if specific correlations exist between cognitive measures and psychotic dimensions in schizophrenic subjects and if similar correlations, between cognition and schizotypal dimensions, are present in non-psychotic subjects.MethodsWe administered the same battery of cognitive tests (Source Monitoring, Verbal Fluency [VF] and Stroop tests) to schizophrenic subjects (N = 54), their first-degree relatives (N = 37) and controls (N = 41). Scores of negative, positive and disorganisation dimensions were derived from the Signs and Symptoms of Psychotic Illness scale in schizophrenic subjects, and from the Schizotypal Personality Questionnaire in relatives and controls.ResultsIn schizophrenic subjects, as hypothesised, the negative dimension correlated with performance on VF and disorganisation with performance in the Stroop test. The positive dimension did not correlate with any cognitive measure.With only one exception, the significant correlations observed in non-psychotic subjects did not match correlations seen in schizophrenic subjects. In non-psychotic subjects greater disorganisation was associated with more clustered words in VF suggesting that excessive automatic spreading of activation in semantic networks could underlie this dimension.ConclusionAs a whole, data lent partial support to our hypothesis of specific cognitive–clinical correlations in schizophrenic subjects but did not support the existence of similar correlations in non-psychotic subjects.     

Substance use in severe mental illness: self-medication and vulnerability factors

The aim of this article is to examine the onset and clinical correlates of substance use in patients with psychotic disorders. One hundred and eight inpatients and outpatients with DSM-IV psychotic disorders were evaluated with the SCI-SUBS, an instrument designed to explore the spectrum of substance use and its clinical correlates. Comparisons were made between subjects with (n = 47) and without (n = 61) a DSM-IV diagnosis of substance use disorder (SUD). In patients with an early onset of psychosis (< 17 years), the onset of SUD was subsequent. Patients with SUD had higher substance sensitivity, higher sensation-seeking traits and were more likely to self-medicate than patients without SUD. The reasons for self-medication endorsed by patients with SUD included relieving depression, achieving or maintaining euphoria, improving self-confidence and social abilities. Our results, based on a cross-sectional study, suggest that early onset of psychosis, substance sensitivity and sensation-seeking traits represent vulnerability factors for SUD. The relationships between SUD and psychosis should be examined systematically and clarified in longitudinal studies.     

Increased risk of psychosis in patients with hearing impairment: Review and meta-analyses

Several studies suggest hearing impairment as a risk factor for psychosis. Hearing impairment is highly prevalent and potentially reversible, as it can be easily diagnosed and sometimes improved. Insight in the association between hearing impairment and psychosis can therefore contribute to prevention of psychosis. This paper provides meta-analyses of all epidemiologic evidence on the association between hearing impairment and psychosis and summarizes mechanisms that potentially underlie this relationship.Meta-analyses showed an increased risk of hearing impairment on all psychosis outcomes, such as hallucinations (OR 1.40(95%CI 1.18–1.65; n = 227,005)), delusions (OR 1.55(95%CI 1.36–1.78; n = 250,470)), psychotic symptoms (OR 2.23(95%CI 1.83–2.72; n = 229,647) and delirium (OR 2.67(95%CI 2.05–3.48; n = 12,432). Early exposure to hearing impairment elevated the risk of later development of schizophrenia (OR 3.15(95%CI 1.25–7.95; n = 50,490)).Potential mechanisms underlying this association include loneliness, diminished theory of mind, disturbances of source monitoring and top-down processing and deafferentiation. Early assessment and treatment of hearing impairment in patients with (high risk of) psychosis may be essential in psychosis treatment and prevention.