Psychiatric illness in first-degree relatives of patients with paranoid psychosis, schizophrenia and medical illness

The contribution of epidemiology to the study of diagnosis

Psychiatric diagnoses provide short labels for diseases or discrete symptom clusters. They should designate the same throughout the world, give information about course, outcome and indications for therapy as well as provide an heuristic basis for etiological research. Hence, the core question is how to attain an optimal representation of real morbidity in diagnosis, sets of diagnostic criteria and diagnostic classifications. Clinical observation can be improved considerably by multi-centre field trials, as applied in the preparation of ICD-10 and DSM-IV. But the approach has considerable limitations due to a lack of external measures in many psychiatric disorders and a highly limited representation of many diagnostic groups in clinical populations. Therefore, epidemiological methods are required in validating diagnosis and diagnostic criteria. The simplest way is to supplement clinical multicentre diagnostic studies by general-practice studies, but these, also, cannot fully replace population studies. Operational diagnosis and case criteria can be defined either categorically or dimensionally. Most of the categorical diagnoses in ICD-10 or DSM III also include dimensional characteristics. The impact of various diagnostic criteria, particularly cut-offs of dimensional characteristics, on the assignment of a diagnosis and, thus, on the morbidity figures of a diagnostic category is demonstrated by data from a large representative sample of first-admitted schizophrenics. Attempts at etiological validation by methods of genetic epidemiology provide limited support for Kraepelin's dichotomous model of functional psychoses. Validation by epidemiological course studies has shown that the stability of diagnosis in functional psychoses differs according to the sets of diagnostic criteria of different classification systems.

Risk of schizophrenia in relatives of individuals affected by schizophrenia: A meta-analysis

A meta-analysis was conducted to estimate schizophrenia incidence in first-degree relatives (FDRs) of probands diagnosed with schizophrenia. The aim was to inform future schizophrenia research and improve accuracy of risk communication to patients. Schizophrenia risk in FDRs with 1 or 2 probands with schizophrenia was investigated by conducting a systematic review of cohort and case-control studies with the following criteria: published between 1977 and 2018; reported odds ratios (OR), relative risk (RR) or sufficient raw data to calculate OR or RR; used appropriate diagnostic criteria; and reported systematic proband recruitment and ascertainment of relatives. Studies were obtained via EMBASE and MEDLINE electronic database searches. From an initial 5755 articles, 19 met the inclusion criteria. Mean effect sizes across studies were estimated using random effects methods. Estimates for schizophrenia risk were OR = 7.69 (95% CI 5.11-11.56) for FDRs of one proband with schizophrenia compared to healthy control probands, increasing to OR = 11.11 (95% CI = 1.45-85.02) for FDRs with two probands with schizophrenia. These findings support the existing literature suggesting significant genetic liability for schizophrenia. The results can be used to educate individuals with a family history of schizophrenia about their risk.

Delusional disorder: The role of personality and emotions on delusional ideation

The relationship between personality and Delusional Disorder in still debated. The present study aimed to evaluate the role of personality features and emotional dispositions on the proneness to delusional beliefs, through the lens of a dimensional approach. 91 outpatients were administered the Structured Interview for DSM-IV Personality Disorders, the Pathological Narcissism Inventory, the Positive and Negative Affect Schedule and the Peters et al. Delusions Inventory. Delusion proneness was positively related to the "Hiding the Self" domain of narcissistic vulnerability and to paranoid traits and negatively related to "Positive Affect". Paranoid traits and "Hiding the Self" significantly interacted in influencing delusion ideation. These data suggest that proneness to delusion depends, at least in part, on a complex interplay between specific emotional and paranoid dispositions within personality.

Mistrustful and Misunderstood: A Review of Paranoid Personality Disorder

PURPOSE OF REVIEW

Paranoid Personality Disorder (PPD) has historically been neglected by science out of proportion to its prevalence or its association with negative clinical outcomes. This review provides an update on what is known about PPD regarding its prevalence, demographics, comorbidity, biological mechanism, risk factors, and relationship to psychotic disorders.

RECENT FINDINGS

PPD has long been the subject of a rich and prescient theoretical literature which has provided a surprisingly coherent account of the psychological mechanism of non-delusional paranoia. Available data indicate that PPD has a close relationship with childhood trauma and social stress. Descriptive data on a sample of 115 individuals with Paranoid Personality Disorder is examined in comparison with a group of individuals with Borderline Personality Disorder. The descriptive data largely confirm previously identified relationships between Paranoid Personality Disorder and childhood trauma, violence, and race. We identify important similarities to and differences from Borderline Personality Disorder.

SUMMARY

PPD continues to be an important construct in the clinic and the laboratory. Available data lead to a reconsideration of the disorder as more closely related to trauma than to schizophrenia.

Influence of interactions between genes and childhood trauma on refractoriness in psychiatric disorders

Psychiatric disorders are excellent disease models in which gene-environmental interaction play a significant role in the pathogenesis. Childhood trauma has been known as a significant environmental factor in the progress of, and prognosis for psychiatric illness. Patients with refractory illness usually have more severe symptoms, greater disability, lower quality of life and are at greater risk of suicide than other psychiatric patients. Our literature review uncovered some important clinical factors which modulate response to treatment in psychiatric patients who have experienced childhood trauma. Childhood trauma seems to be a critical determinant of treatment refractoriness in psychotic disorder, bipolar disorder, major depressive disorder, and post-traumatic stress disorder. In patients with psychotic disorders, the relationship between childhood trauma and treatment-refractoriness appears to be mediated by cognitive impairment. In the case of bipolar disorder, the relationship appears to be mediated by greater affective disturbance and earlier onset, while in major depressive disorder the mediating factors are persistent, severe symptoms and frequent recurrence. In suicidal individuals, childhood maltreatment was associated with violent suicidal attempts. In the case of PTSD patients, it appears that childhood trauma makes the brain more vulnerable to subsequent trauma, thus resulting in more severe, refractory symptoms. Given that several studies have suggested that there are distinct subtypes of genetic vulnerability to childhood trauma, it is important to understand how gene-environment interactions influence the course of psychiatric illnesses in order to improve therapeutic strategies.

Brain change trajectories that differentiate the major psychoses

BACKGROUND

Bipolar disorder and schizophrenia are highly heritable, often chronic and debilitating psychotic disorders that can be difficult to differentiate clinically. Their brain phenotypes appear to overlap in both cross-sectional and longitudinal structural neuroimaging studies, with some evidence to suggest areas of differentiation with differing trajectories. The aim of this review was to investigate the notion that longitudinal trajectories of alterations in brain structure could differentiate the two disorders.

DESIGN

Narrative review. We searched MEDLINE and Web of Science databases in May 2016 for studies that used structural magnetic resonance imaging to investigate longitudinal between-group differences in bipolar disorder and schizophrenia. Ten studies met inclusion criteria, namely longitudinal structural magnetic resonance studies comparing bipolar disorder (or affective psychosis) and schizophrenia within the same study.

RESULTS

Our review of these studies implicates illness-specific trajectories of morphological change in total grey matter volume, and in regions of the frontal, temporal and cingulate cortices. The findings in schizophrenia suggest a trajectory involving progressive grey matter loss confined to fronto-temporal cortical regions. Preliminary findings identify a similar but less severely impacted trajectory in a number of regions in bipolar disorder, however, bipolar disorder is also characterized by differential involvement across cingulate subregions.

CONCLUSION

The small number of available studies must be interpreted with caution but provide initial evidence supporting the notion that bipolar disorder and schizophrenia have differential longitudinal trajectories that are influenced by brain maturation.

Depression predicts persistence of paranoia in clinical high-risk patients to psychosis: results of the EPOS project

BACKGROUND

The link between depression and paranoia has long been discussed in psychiatric literature. Because the causality of this association is difficult to study in patients with full-blown psychosis, we aimed to investigate how clinical depression relates to the presence and occurrence of paranoid symptoms in clinical high-risk (CHR) patients.

METHODS

In all, 245 young help-seeking CHR patients were assessed for suspiciousness and paranoid symptoms with the structured interview for prodromal syndromes at baseline, 9- and 18-month follow-up. At baseline, clinical diagnoses were assessed by the Structured Clinical Interview for DSM-IV, childhood adversities by the Trauma and Distress Scale, trait-like suspiciousness by the Schizotypal Personality Questionnaire, and anxiety and depressiveness by the Positive and Negative Syndrome Scale.

RESULTS

At baseline, 54.3% of CHR patients reported at least moderate paranoid symptoms. At 9- and 18-month follow-ups, the corresponding figures were 28.3 and 24.4%. Depressive, obsessive-compulsive and somatoform disorders, emotional and sexual abuse, and anxiety and suspiciousness associated with paranoid symptoms. In multivariate modelling, depressive and obsessive-compulsive disorders, sexual abuse, and anxiety predicted persistence of paranoid symptoms.

CONCLUSION

Depressive disorder was one of the major clinical factors predicting persistence of paranoid symptoms in CHR patients. In addition, obsessive-compulsive disorder, childhood sexual abuse, and anxiety associated with paranoia. Effective pharmacological and psychotherapeutic treatment of these disorders and anxiety may reduce paranoid symptoms in CHR patients.

Early Childhood IQ Trajectories in Individuals Later Developing Schizophrenia and Affective Psychoses in the New England Family Studies

Individuals who develop schizophrenia in adulthood exhibit, on average, deficits in childhood cognition relative to healthy controls. However, it remains unclear when in childhood such deficits emerge and whether they are stable across childhood or change (increase or decrease) across development. Importantly, whether the trajectory of childhood cognition differs among youth who later develop affective psychoses (AP) vs schizophrenia as adults remains unresolved. Subjects in the Collaborative Perinatal Project were administered the Stanford-Binet IQ test at age 4 and the Wechsler Intelligence Scale for Children at age 7. A total of 9809 (54.7%) participants in the New England Study sites were tested at both ages, including 37 who later developed schizophrenia spectrum psychoses (SSP) and 39 who later developed AP. Logistic regression models examined the association of level of and change in childhood IQ and later SSP or AP. Lower overall childhood IQ was associated with higher risk of SSP. Additionally, there was a small mean increase in IQ in the SSP group relative to a mean decrease in the control group from age 4 to 7 such that positive change in IQ was significantly associated with a higher risk of SSP. Neither overall level nor change in IQ was associated with risk of AP. The results are consistent with neurocognitive impairment throughout early childhood specifically for children who later develop schizophrenia, affirming the theory of atypical neurodevelopment in premorbid schizophrenia.

Early intermodal integration in offspring of parents with psychosis

Identifying early developmental indicators of risk for schizophrenia is important for prediction and possibly illness prevention. Disturbed intermodality has been proposed as one important neurodevelopmental risk for schizophrenia. Early intermodal integration (EII) is the infant's ability to link motility and perception and to relate perception across modalities. We hypothesized that infants of parents with schizophrenia would have more EII abnormalities than infants of healthy parents and that infants of parents with affective psychosis would be intermediate in severity. The New England Family Study high-risk sample, ascertained from community populations, was utilized. Eight-month-old infants of parents with schizophrenia (n = 58), affective psychoses (n = 128), and healthy controls (n = 174) were prospectively assessed. Diagnoses of parents were determined 30 years later blind to offspring data. EII measures were grouped into 3 domains characterizing different aspects of infant development: (1) one's own body, (2) objects, and (3) social interactions. Results demonstrated that body- and object-related EII abnormalities were significantly increased for infants of parents with schizophrenia compared with control infants and not significantly increased for infants of parents with affective psychoses. EII abnormalities in relation to social interactions were significantly increased in infants of parents with schizophrenia and affective psychoses. Thus, body- and object-related EII abnormalities were most severe in infants of parents with schizophrenia, supporting the importance of intermodality dysfunction as an early indicator of the vulnerability to schizophrenia. Future research should evaluate how this dysfunction evolves with development and its associations with other psychopathological and neurodevelopmental deficits in youth at risk for psychosis.

The New England Family Study High-risk Project: neurological impairments among offspring of parents with schizophrenia and other psychoses

This manuscript presents the design and initial outcomes of the New England Family Study's (NEFS) High-Risk Project, one of the few epidemiologically representative cohorts that has prospectively followed a large sample of offspring of parents with both affective and non-affective psychotic disorders from the fetal period forward. The goals of this report are: (1) to describe in some detail the design, data collection methods, and resulting sample of this project; and (2) to prospectively identify and compare rates of childhood neurological impairments among offspring of psychotic and nonpsychotic parents, with a particular emphasis on offspring risk in relation to specific classes of parental psychosis (i.e., affective vs. non-affective psychosis). The investigators identified a pool of 755 parents with potential psychotic disorders, located over 80% of these and confirmed psychotic diagnoses for 212 affected parents and 132 unaffected control parents. At birth, the 259 offspring of parents with psychosis had approximately a twofold increased risk of abnormal neurological functioning compared to offspring of families with no psychotic history. This was most pronounced among the 58 offspring of parents with schizophrenia. Similar trends were observed at ages 1 and 7 years although these did not reach statistical significance. Neither at birth nor at any of the follow-up assessments were the 157 offspring of parents with affective psychosis found to be at elevated risk of neurological impairment. Implications for future research and potential preventive interventions for at-risk individuals are discussed.

Empirical redefinition of delusional disorder and its phenomenology: the DELIREMP study

AIMS

Since Kraepelin, the controversy has persisted surrounding the nature of delusional disorder (DD) as a separate nosological entity or its clinical subtypes. Nevertheless, there has been no systematic study of its psychopathological structure based on patient interviews. Our goal was to empirically explore syndromic subentities in DD.

METHODS

A cross-sectional study was conducted in 86 outpatients with DSM-IV-confirmed DD using SCID-I. Psychopathological factors were identified by factor analysis of PANSS scores. The association between these factors and clinical variables (as per standardized instruments) was analyzed using uni- and multivariate techniques.

RESULTS

PANSS symptoms were consistent with four factors (Paranoid, Cognitive, Schizoid, and Affective dimensions), accounting for 59.4% of the total variance. The Paranoid Dimension was associated with premorbid paranoid personality disorder, more adverse childhood experiences, chronic course, legal problems, worse global functioning, and poorer treatment adherence and response. The Cognitive Dimension was associated with poorer cognitive functioning, premorbid substance abuse, comorbid somatic diseases, mainly non-prominent visual hallucinations, fewer comorbid depressive disorders, and poorer global functioning. The Schizoid Dimension was associated with being single, a family history of schizophrenia, premorbid personality disorders (largely schizoid and schizotypal), non-prominent auditory hallucinations, and dysthymia. Finally, the Affective Dimension was associated with a family history of depression, premorbid obsessive personality, somatic delusions, absence of reference delusions, tactile and olfactory hallucinations, depressive and anxiety disorders, risk of suicide, and higher perceived stress.

CONCLUSION

The identification and clinical validation of four separate psychopathological dimensions in DD provide evidence toward a more accurate conceptualization of DD and its types.

Evidence of reduced selective attention in schizotypal personality disorder

It has been shown that high-schizotypy and schizophrenic participants demonstrate increased task-switching costs, although high-schizotypy participants present this pattern only in incongruent trials (Cimino & Haywood, 2008). In this study, we aim to explore whether this results from difficulties in selective attention or task control. A total of 18 participants with high levels of psychometrically defined schizotypy and 16 participants with low scores were tested in two different versions of a task-switching paradigm. Participants were asked to switch between attending to the color or the shape of bidimensional objects following a previous cue. Two versions of the task were investigated, one involving only switches in the perceptual dimension to attend (color or shape) and another also switching the response set. High-schizotypy subjects consistently showed increased switch costs in incongruent trials for both versions of the tasks, demonstrating a deficit in the selection of the perceptual dimension instead of the selection of the response rules.

Sex-specific rates of transmission of psychosis in the New England high-risk family study

Recent molecular genetic studies have demonstrated X-chromosome abnormalities in the transmission of psychosis, a finding that may contribute to understanding sex differences in the disorder. Using our family high risk paradigm, we tested the hypothesis that there are sex-specific patterns of transmission of psychosis and whether there is specificity comparing nonaffective- with affective-type psychoses. We identified 159 parents with psychoses (schizophrenia psychosis spectrum disorders (SPS, n=59) and affective (AP, n=100)) and 114 comparable, healthy control parents. 203 high risk (HR) and 147 control offspring were diagnostically assessed (185 females; 165 males). We compared the proportion of male:female offspring with psychoses by affected parent sex and the consistency for SPS compared to AP parents, and tested (using exact logistic regression) whether the male:female ratio for affected offspring differed significantly between affected mothers and affected fathers. Risk of psychosis in offspring was a function of the sex of the parent and offspring. Among ill mothers, 18.8% of their male offspring developed psychosis compared with 9.5% of their daughters. In contrast, among ill fathers, 3.1% of their male offspring developed psychosis compared with 15.2% of their daughters. The male:female ratio for affected offspring differed significantly (p < 0.05) between affected mothers and fathers. Similar patterns held for SPS and AP. Results demonstrated sex-specific transmission of psychosis regardless of psychosis-type and suggest X-linked inheritance. This has important implications for molecular genetic studies of psychoses underscoring the impact of one's gender on gene-brain-behavior phenotypes of SCZ.

Specificity of familial transmission of schizophrenia psychosis spectrum and affective psychoses in the New England family study's high-risk design

CONTEXT

There is a long history of research on the familial transmission of schizophrenia and other psychoses. However, few studies have investigated the specificity of the transmission of schizophrenia-psychosis spectrum (SPS) disorders and affective psychoses (APs) or observed high-risk offspring into mid-adulthood.

OBJECTIVES

To investigate the transmission of psychoses from parents to their offspring and the specificity of transmission across psychosis subtypes.

DESIGN

High-risk follow-up study.

SETTING

New England Family Study's High-Risk Study, with population-based community sampling from Boston, Massachusetts, and Providence, Rhode Island.

PARTICIPANTS

A total of 203 high-risk offspring of 159 parents with diagnoses of psychoses (SPS and AP) and 147 control offspring of 114 control parents.

MAIN OUTCOME MEASURES

Systematically assessed research DSM-IV psychiatric diagnoses for adult offspring.

RESULTS

Compared with those of control parents, offspring of parents with SPS had a significant, almost 6-fold elevated risk of SPS disorders and a nonsignificant doubling of risk for AP. Offspring of parents with AP had a significant 14-fold elevated risk for AP compared with offspring of controls; for SPS disorders, the risk doubled but was not significant.

CONCLUSION

Having a parent with psychosis significantly increased the risk for psychosis among offspring and demonstrated specificity for the transmission of SPS disorders and APs within families.

Prevalence of psychotic and non-psychotic disorders in relatives of patients with a first episode psychosis

BACKGROUND

Family members of individuals with schizophrenia suffer from elevated rates of schizophrenia-spectrum disorders (SSD) and other forms of psychopathology. However, few studies have examined familial psychopathology in probands with a first episode of psychosis (FEP). We systematically evaluated family history in patients experiencing an affective or non-affective FEP.

METHODS

The Family Interview for Genetic Studies was used to obtain diagnostic information on all first- and second-degree relatives of probands admitted to a specialized FEP program. Probands were 94 previously untreated patients suffering from a first-episode of affective or schizophrenia spectrum psychosis, aged 14 to 30. The interview ascertained diagnoses of psychotic disorders, affective disorders, substance-use disorders (SUD), and schizophrenia-related personality disorders.

RESULTS

One in five probands (19.1%) had a history of psychosis among their first-degree relatives, while 34.0% had any relative with psychosis. Fewer probands had a family history of SSD (7.4% with a first-degree history and 18.1% with a history among any relatives). Over half (53.2%) of probands had a first-degree relative with Major Depressive Disorder, and 38.3% had a first-degree relative with a SUD. Overall, 69.9% of probands had a first-degree relative with a mental disorder. The proportion of probands with a family history of any of these diagnoses did not vary by proband diagnosis (affective or SS Psychosis), though probands with co-morbid SUD were more likely to have a family history of substance abuse.

CONCLUSIONS

Diverse psychopathology is commonly present in families of FEP patients and may imply a generalized vulnerability to psychiatric disorders to be greater in such families compared to specific vulnerability to SS or affective psychosis. These findings may also have implications for provision of care for the probands.

Allelic association of G72/G30 with schizophrenia and bipolar disorder: a comprehensive meta-analysis

The G72/G30 gene complex (G72 also known as D-amino acid oxidase activator, DAOA) and its chromosomal region 13q32-34 have been linked and associated with both schizophrenia (SCZ) and bipolar disorder (BP) in multiple studies, including our initial association report on BP. However, the inconsistency of associated variants across studies is obvious. Previous meta-analyses had small data sets. The present meta-analysis combined 18 association articles published before April of 2007. There were 19 independent studies of SCZ, with 4304 cases, 5423 controls, and 1384 families, and four independent studies of BP with 1145 cases, 1829 controls, and 174 families. Of 15 single nucleotide polymorphisms (SNPs) analyzed in the 95-kb G72/G30 gene region, M18/rs947267 and M22/rs778293 showed association with SCZ in Asians, and M24/rs1421292 with SCZ in Europeans. The associations of C allele at M18 and A allele at M22 with SCZ in Asians survived conservative Bonferroni correction for multiple testing for 15 markers and subgroup analysis (adjusted P=0.0000253 for M18; adjusted P=0.009 for M22). No single maker showed evidence of overall association with BP. These results suggest that G72/G30 may influence susceptibility to schizophrenia with weak effects.

The vulnerability to alcohol and substance abuse in individuals diagnosed with schizophrenia

Individuals with schizophrenia are at increased risk for developing substance abuse disorders. Here, we consider factors that might elevate their risk for substance abuse. The tendency among schizophrenic individuals to overvalue drug-like rewards and to devalue the potential negative consequences of substance abuse may be a contributing factor to their substance abuse risk. This bias, which may partly reflect the convergence of glutamatergic and dopaminergic input to the limbic striatum, also may contribute to disadvantageous decision-making and other impulsive behavior. This propensity to seek drug-like rewards is augmented by alterations in nicotinic cholinergic, GABAergic, glutamatergic, and cannabinnoid receptor function associated with schizophrenia that increase the abuse liability of low doses of nicotine, ethanol, and perhaps cannabis, and augment the dysphoric effects of higher doses of ethanol and cannabis. The distortions in reward processing and altered response to substances of abuse also increase the likelihood that individuals with schizophrenia will self-medicate their subjective distress with abused substances. The focus on distinctions between motivation and reward with respect to substance abuse risk by schizophrenic patients suggests a need for a reconsideration of the construct of "negative symptoms" for this dually-diagnosed patient group.

Risk factors for cocaine-induced paranoia in cocaine-dependent sibling pairs

OBJECTIVE

Cocaine-induced paranoia (CIP), an irrational intense suspicion of others, is a common manifestation of cocaine dependence. Both environmental and genetic factors are thought to play a role, but the specific nature of such contributions is poorly understood.

METHODS

Demographic, diagnostic, and cocaine-use data were obtained from 420 cocaine-dependent, genetically confirmed, full-sibling pairs (N=840 subjects) interviewed with the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA). Probands with and without CIP were compared; then, factors associated with sibling CIP status were analyzed by logistic regression. Alcohol dependence, a known heritable phenotype, was analyzed as a positive control.

RESULTS

Of 420 probands, 273 (65%) experienced CIP. Probands with CIP were more severely dependent upon cocaine, had an earlier age of onset, were more likely to smoke cocaine, and used cocaine less frequently during the preceding year. Independent analyses of siblings replicated two of the former (i.e., dependence severity and age of onset). Probands with CIP also had a non-significantly higher proportion of siblings with the trait (66% versus 59%). Probands with concurrent alcohol dependence were confirmed to have significantly higher rates of alcoholism among their siblings.

CONCLUSIONS

Severity of cocaine dependence and age of onset appear to be important risk factors for CIP. Concordance for CIP between siblings did not emerge as significant in our analyses.

Genetic associations between delusional disorder and paranoid schizophrenia: A novel etiologic approach

OBJECTIVES

Genetic associations between delusional disorder and paranoid schizophrenia are not well understood, although involvement of biological factors has been suspected. We investigated the incidence of human leukocyte antigen (HLA) class I alleles in patients with delusional disorder and paranoid schizophrenia, first, to explore a possible immunogenetic etiology of these paranoid disorders and, second, to determine whether they share similar etiologic mechanisms.

METHOD

We employed a nested case-control study design. Psychiatric reference data were available for 38,500 patients attending a hospital-based psychiatric outpatient department between 1998 and 2005. We enrolled 100 patients with delusional disorder and 50 patients with paranoid schizophrenia as the subject cases, using DSM-IV criteria. We considered equivalent numbers of healthy volunteers matched for age and ethnic background as control subjects. All subjects came from an India-born Bengali population. We applied the polymerase chain reaction-based molecular typing method to all patients and healthy subjects.

RESULTS

The HLA-A*03 gene is significantly associated with delusional disorder as well as with paranoid schizophrenia. This HLA gene alone or in linkage disequilibrium with other HLA genes or other closely linked non-HLA genes may influence susceptibility to delusional disorder and paranoid schizophrenia.

CONCLUSIONS

The study reveals important associations between HLA genes and paranoid disorders. Delusional disorder and paranoid schizophrenia may share similar etiologic mechanisms. This preliminary observation may help our understanding of the genetic basis of these paranoid disorders.

Genetics and delusional disorder

This article gives an overview of genetic research approaches and their application to delusional disorder. Most studies have been based on small samples and have had other methodological limitations, so it is not clear whether there is a genetic contribution to the aetiology of delusional disorder. It is unlikely that delusional disorder is strongly related genetically to affective disorder or schizophrenia, but more subtle relationships cannot be ruled out. The rarity of multiply affected families prohibits linkage studies and, to date, molecular genetic investigations have been mainly limited to small association studies of dopamine receptor polymorphisms. A range of considerably larger, epidemiologically rigorous studies is required, but the uncommonness and other features of the disorder put strong limitations on the prospects for ascertaining adequate samples.

Does god play dice with schizophrenia? A probabilistic model for the understanding of causation in mental illness

While the pure sciences have moved over the XX century from the certainties of the Laplacian mechanistic models to probabilistic ones, such as quantum physics, the attempts to explain the causation in mental illness are still stuck to deterministic frameworks which are deceptively reassuring, but also too simplistic to approach problems of such a complexity. The deterministic approach has led to several false leads that have affected research in the aetiology in mental illness, especially schizophrenia, and only moving to probabilistic models will allow an understanding of the causal processes. In this paper is challenged the almost universally accepted assumption that, to explain the lack of complete concordance amongst identical twins in schizophrenia, there is the need to resort to environmental aetiological agents. It is described instead how, using a probabilistic framework, a polygenic model without threshold can satisfactorily explain the data available so far without having to resort to environmental factors. The genes predisposing to schizophrenia, probably through a derailment of the neurodevelopment, would have a normal distribution in the general population, while the liability for the illness will increase exponentially with the number of risk genes, with a small minority of the population being at high risk. The average genetic liability to develop schizophrenia in individuals who later are affected by the disorder is around 50%. The adoption of a probabilistic model for the understanding of the inheritance of schizophrenia has therefore far reaching consequences, revolutionizing the interpretation of the twin studies, allowing a consistent model which does not require environmental interventions in the aetiology of schizophrenia and offering a framework to make sense of findings from the epidemiological research which are not satisfactorily explained by the deterministic models adopted so far.

Persecutory delusions: a review and theoretical integration

Persecutory (paranoid) delusions are a frequently observed clinical phenomenon. In recent years, an increasing volume of research has attempted to explain these types of beliefs in terms of psychological mechanisms. Theories have emphasized early experience, perceptual abnormalities, motivational factors, and information-processing deficits. In this article we review relevant findings, including our own studies of the role of causal attributions and theory of mind deficits. We propose a new integrative model that builds on this work. The core of the model is an account of the way that causal attributions influence self-representations, which in turn influence future attributions: the attribution--self-representation cycle. We argue that biases in this cycle cause negative events to be attributed to external agents and hence contribute to the building of a paranoid world view. These abnormalities are amenable to investigation by functional neuroimaging, and recent studies have implicated specific areas of neuroactivation. However, these findings do not necessarily suggest that paranoid delusions are entirely biological in origin, and there is evidence that adverse early experience may play a role in determining the development of a cognitive vulnerability to paranoid thinking.

Olanzapine augmentation of fluvoxamine-refractory obsessive-compulsive disorder (OCD): a 12-week open trial

A few studies have tried antipsychotic augmentation in obsessive-compulsive disorder (OCD) patients who are non-responders to selective serotonin reuptake inhibitors. The aim of this study was to investigate the efficacy and tolerability of olanzapine addition to fluvoxamine-refractory OCD patients and to assess if a comorbid chronic tic disorder or a concomitant schizotypal personality disorder was associated with response. Twenty-three OCD non-responders to a 6-month, open-label trial with fluvoxamine (300 mg/day) entered a 3-month open-label trial of augmentation with olanzapine (5 mg/day). OC symptom change was measured with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the Clinical Global Impression (CGI) scale. Differences between responders and non-responders were assessed with regard to age, sex, duration of illness, baseline Y-BOCS score, and comorbidity with chronic tic disorders or schizotypal personality disorder. A significant decrease of mean Y-BOCS score between pre- and post-treatment (26. 8+/-3.0 vs. 18.9+/-5.9) was found at endpoint. Ten patients (43.5%) were rated as responders. The most common side effects were mild to moderate weight gain and sedation. In our sample, three patients (13. 04%) had a chronic motor tic disorder, and four (17.39%) had a codiagnosis of schizotypal personality disorder. Concomitant schizotypal personality disorder was the only factor significantly associated with response. It appears that augmentation of olanzapine in fluvoxamine-refractory OCD may be effective in a large number of patients, including those with comorbid schizotypal personality disorder.

The concept of target features in schizophrenia research

Target features are clinical or neurobiological characteristics that are expressions of the underlying predisposition to an illness. They comprise a wide range of phenomena, from the classic signs and symptoms of psychopathology to sophisticated measures of brain structure and function. For schizophrenia, many target features have been identified. These include eye tracking dysfunction, attentional impairment, allusive thinking, neurological signs, thought disorder, characteristic auditory evoked potentials, neuropsychological impairment, structural brain abnormalities and functional brain abnormalities. In their most pathological forms, these features are present among many schizophrenic patients, yet it is their presence among their non-psychotic relatives that shows them to be target features. We discuss the theoretical background for target features, present examples and describe how the discovery of target features has implications for schizophrenia research.

Negative symptoms of familial schizophrenia breed true in unstable (vs. stable) cerebral-ventricle pedigrees

A pattern of negative symptoms associated with a high rate of ongoing brain and ventricular instability has been described in a cohort of schizophrenia spectrum probands (patients with schizophrenia, schizoaffective disorder depressed and bipolar, and psychosis NOS) (Garver, D.L., Nair, T.R., Christensen, J.D., Holcomb, J., Ramberg, J., Kingsbury, S., 1999. Differential patterns of premorbid functioning, symptoms and neuroleptic response in stable and unstable ventricular-volume schizophrenia. Neuropsychopharmacology 20, in press). The present study contrasts the prevalence of negative symptoms in first- and second-degree relatives of probands with unstable ventricle volume (UnsVV) and stable ventricle volume (SVV). One hundred and sixteen first- and second-degree relatives of 10 probands were interviewed using the SANS, the 'Characterization of Course: "Pattern of Symptoms"' [from Comprehensive Assessment of Symptoms and History (CASH)], SCID and SCID-II by interviewers blind to the status of the proband. Thirty-five of the 116 family members met DSM-IV criteria for schizophrenia, SA depressed, 'Cluster A' of the SCID-II (paranoid, schizotypal, schizoid personality disorder), psychosis NOS, or psychotic affective disorder. These 35 family members were defined as falling within a 'schizophrenia spectrum' as described by Farmer, A.E., McGuffin, P., Gottesman, I.I., 1987. Arch. Gen. Psychiatry 44, 634-641, but with the addition of DSM-IV affective psychosis. On that basis, the 35 members were considered 'affected family members' (AFMs). The remaining 81 family members were considered unaffected. The 'predominant symptoms of illness' (during the past 2-3 years) for 25 of the 35 AFMs could be characterized according to the 'Patterns of Symptoms' derived from the CASH. Twenty-five of the 35 AFMs were found to maintain a predominant symptom pattern during the course of illness, which could be characterized according to the 'Pattern of Symptoms' as 'predominantly positive' or 'predominantly negative'. Three of the probands had UnsVV; seven had SVV. Of the 35 AFMs, 11 were related to the UnsVV probands, and 24 were relatives of the SVV probands. The nine rated AFMs of the UnsVV probands showed a trend toward higher SANS scores (7.3 +/- 5.1) (mean +/- s.d.) than the 20 rated AFMs of SVV probands (4.3 +/- 5.1) (p = 0.08) at the time of the interview. Eighty-three per cent (eight of 10) of rated affected pedigree members of the pedigrees delineated by probands with UnsVV probands had a predominantly negative symptom course of illness, and 96% (23 of 24) of rated affected pedigree members of the pedigrees with SVV probands had a predominantly positive symptom course of illness during the preceding 2-3 years (p = 0.002). None of the 12 rated affected pedigree members within pedigrees having UnsVV probands were married at the time of the interview; 45% (14 of 31) of affected pedigree members having SVV probands were married (p = 0.004). A psychiatric disorder, characterized by unstable cerebral ventricles and predominant negative symptoms (including avoidance/failure of marital relationships) appears symptomatically to breed true in pedigrees containing schizophrenia-like illnesses.

Psychiatric morbidity in the first-degree relatives of schizophrenic patients

There is increasing evidence that genetic factors play a role in the etiology of schizophrenic disorders. One thousand eighty-nine first-degree relatives of schizophrenics and 1,137 controls were studied to discover their psychiatric morbidity. Psychiatric morbidity was found in 16.34% of the first-degree relatives (FDR) of schizophrenics (parents, 5.69%; siblings, 7.71%; offspring, 2.94%) as compared to 6.9% in the controls (P < 0.001). Schizophrenia was found in 8.3% of the patient group, which was significantly higher (0.2%) as compared to the controls. Schizoid-schizotypal personality disorder was found in 3.03% of FDRs of the schizophrenic group. Depressive disorder was found in 4.4% and 2.1% in the control and patient group, respectively, which was statistically significant. Morbidity risk of schizophrenia was found in 16.97%, 6.22% and 5.79% of schizophrenia, schizoid-schizotypal personality disorder and depressive disorder, respectively, in the FDR of schizophrenic group.

The nature of 'transient' and 'partial' psychoses: findings from the Northwick Park 'Functional' Psychosis Study

Three hundred and twenty-six consecutively admitted patients with definite or possible functional psychotic illnesses to which no diagnostic classification had been applied were followed up after 2.5 years. In 86 cases symptomatology had been inadequate for the patients to enter the functional psychosis study, and in 75 cases this was because the symptoms were partial or transient. These patients were compared at follow-up with those who fulfilled operational criteria for schizophrenic, affective or schizoaffective psychoses. Differences between the 'partial' cases and those fulfilling specific diagnostic criteria were few, but the transient cases fared significantly better. Although the transient illnesses were recurrent, at follow-up at 2.5 years they appeared to have a good outcome in terms of social variables and symptomatology.

Schizophreniform disorder, delusional disorder and psychotic disorder not otherwise specified: clinical features, outcome and familial psychopathology

The relationship between DSM-III-R schizophreniform disorder, delusional disorder (DD) and psychotic disorder not otherwise specified (PD-NOS) and schizophrenia and affective illness (AI) remains uncertain. We explore this question in the Roscommon Family Study by examining symptoms, outcome and patterns of psychopathology in relatives. Probands were selected from a population-based case registry in the west of Ireland with an ICD-9 diagnosis of schizophrenia or AI. Personal interviews were conducted with 88% of traceable, living probands, a mean of 16 years after onset, and 86% of traceable, living first-degree relatives. Best-estimate diagnoses were made at follow-up. Schizophreniform disorder, DD and PD-NOS constituted 6.4%, 2.8% and 7.5%, respectively, of all probands with a registry diagnosis of schizophrenia. Probands with schizophreniform disorder had prominent positive psychotic symptoms, negligible negative symptoms and a good outcome, comparable to that seen in AI probands. Their relatives had an excess risk of schizophrenia spectrum illness but not AI. Probands with DD had prominent delusions but no other psychotic symptoms, few negative symptoms, fair to good outcome and an increased risk in relatives for alcoholism. Probands with PD-NOS had both moderate positive and negative psychotic symptoms, a poor to fair outcome and a substantially elevated risk in relatives of schizophrenia and schizophrenia spectrum disorders but not AI.(ABSTRACT TRUNCATED AT 250 WORDS)

Schizophrenia in the Afro-Caribbean community

Previous studies have shown high rates of schizophrenia among the Afro-Caribbean population in Britain. In order to assess the role of genetic factors in the aetiology of this phenomenon, we have used a standardised family history method (FHRDC) to compare lifetime morbidity risks for first-degree relatives of Afro-Caribbean and white patients with RDC schizophrenia admitted in Central Manchester between 1982 and 1988. Lifetime morbidity risk for parents of Afro-Caribbean subjects was 8.9%, and for parents of white patients 8.4%. For the siblings of black probands, however, the risk was 15.9%, as compared with 1.8% for white siblings (P < 0.05). Among siblings of UK-born Afro-Caribbean probands, morbid risk was even higher at 27.3% (P = 0.001). High rates among siblings of younger Afro-Caribbean patients are consistent with previous reports of a higher incidence in the UK-born. These observations suggest that schizophrenia among Afro-Caribbeans is no less familial than for the remainder of the population, but that the increased frequency of the disorder is due to environmental factors which are most common in the Afro-Caribbean community, and capable of precipitating schizophrenia in those who are genetically predisposed.

Schizotypal and paranoid personality disorder in the relatives of patients with schizophrenia and affective disorders: a review

This review considers the possible familial relationship of schizotypal and paranoid personality disorders (SPD, PPD) to schizophrenia (SCZ) and affective disorders (AD). There have been few controlled studies on familial risk of SPD and PPD based on direct semi-structured interviews of relatives, blind to proband diagnosis. Three of six studies reported increased familial risk of SPD for SCZ probands, but with considerable variability in estimates of this risk. None of four studies reported a significant relationship between AD and familial SPD. There is substantial but less consistent evidence for a familial relationship between PPD and SCZ: three of six studies supported such a relationship, but one large study reported increased familial risk of PPD for AD and not for SCZ probands. There is also some evidence that negative symptoms are most characteristic of SPD in relatives of SCZ probands. Also discussed are issues concerning the adequacy of current criteria for defining schizophrenia spectrum pathology, and of diagnostic methods in this area.

The genetics of bipolar disorder

Growing interest in the application of molecular biological techniques to psychiatric disorders has reinvigorated interest in the genetics of the psychoses. It is therefore timely to review the current state of knowledge of the genetics of bipolar disorder. Family, twin and adoption studies are all consistent in confirming the strongly heritable nature of this condition. As segregation analyses have been unable to determine the mode of transmission of bipolar disorder, ongoing linkage analyses using DNA markers will be crucial in determining whether this condition is due to a single major gene, a small number of genes, or multifactorial polygenic inheritance.

Distribution of a novel mutation in the first exon of the human dopamine D4 receptor gene in psychotic patients

Disturbances in dopaminergic transmission have been implicated in the etiology of psychotic disorders. Interindividual differences in deoxyribonucleic acid (DNA) sequences coding for dopamine receptor proteins might contribute to the genetic background of these diseases. We have identified a variation in exon 1 of the dopamine D4 receptor (DRD4) gene, which is characterized by a polymorphic 12 base pair (bp) repeat. This repeat codes for a sequence of four amino acids in the extracellular N-terminal part of the receptor, which borders the first putative transmembrane domain. The 12bp repeat occurs as a two-fold repeat in the more common variant (A1 allele) and is represented only once in the rarer one (A2 allele). The frequency of this DNA polymorphism was determined in a sample of 59 patients suffering from delusional disorder, in 79 schizophrenic patients, and in 75 control subjects. Sixteen (27%) of the 59 patients with delusional disorder carried the A2 allele compared with six (8%) of the controls. The observed difference in genotype frequencies between patients with delusional disorder and controls was highly significant. There were no significant differences in genotype frequencies between schizophrenics and controls: Our results strongly suggest the involvement of genetic variation in the DRD4 gene in conferring susceptibility to delusional disorder.

3H-spiperone binding capacity in mononuclear cells: a family study

1. A family study was carried out using a putative biological vulnerability trait in families of schizophrenics and schizoaffective indexprobands to investigate, if the clinical phenotype and a biological marker for schizophrenia are cosegregating within families. 2. The binding capacity of the dopamine antagonist spiperone to mononuclear cells was investigated in 21 indexprobands and a total of 147 first and second degree relatives. 3. Increased binding capacity could be found in 17 indexprobands and in their affected relatives, independently from clinical diagnosis and in 22% of their normal relatives. 4. No increased binding capacity was found in 4 indexprobands and in their affected relatives and not n any of the unaffected relatives. These results indicate, that increased spiperone binding may cosegregate with the risk for functional psychoses and that families, loaded with psychiatric disturbances may be distinguished on a biological basis.

DSM-III-R personality disorders in parents of schizophrenic patients

This study examines the frequency of DSM-III-R personality disorders in parents of 58 patients who were admitted consecutively to a New York State psychiatric hospital with a first admission for a schizophrenia-like psychosis. For comparison, a control group of 65 families were randomly recruited who were in the same age group and denied any psychiatric history in their immediate families. Significantly more parents of the patients had a diagnosed personality disorder than controls. These were classified as schizoid, schizotypal, histrionic, and sadistic types by DSM-III-R criteria. While paranoid personality disorder was frequent, it was equally distributed among both groups of parents. These data suggest that the genetic boundaries to a "schizophrenia spectrum" disorder may extend further than previously thought and particularly the specific characteristics that are common to a wide variety of these disorders need to be examined in further analyses.

Psychiatric morbidity in the first-degree relatives of schizophrenic patients

First-degree relatives (FDRs) of 162 schizophrenic and 106 control probands were investigated [corrected]. Psychiatric morbidity was present in 34.8% of FDRs of schizophrenic probands and in 9.2% of FDRs of controls. There was significantly more psychiatric illness in the siblings and parents than in the offspring of both schizophrenic and control subjects. The morbidity risks for schizoid-schizotypal personality disorders, cannabis-use disorder and paranoid personality disorder were significantly higher in the FDRs of schizophrenic patients than in those of controls, suggesting a biological relationship.

Relatedness of schizotypal personality to schizophrenic disorders: multifactorial threshold model

Genetic analysis of schizophrenia and schizotypal personality disorder (SPD) was conducted on two pedigree samples. The results are interpreted in terms of a multifactorial threshold (MFT) model. A high rate of schizophrenia was found in relatives of both samples, but any excess of SPD was found only in relatives of the SPD sample. Based on these data, the hypotheses assuming a single liability with two thresholds (Reich's model) and different liability (Smith's model) for both disorders were rejected. The coefficient of genetic correlation is 0.61. Our data suggest that schizophrenia and SPD are separate nosological entities and that some of the factors which constitute liability to SPD influence the development of schizophrenia, but not vice versa.

Schizophrenia and affective disorder: are they genetically linked?

The relationship between schizophrenic 'spectrum' disorders and affective illness was studied in the nuclear families of 90 chronic schizophrenic probands. An increased risk of schizophrenia and related disorders was demonstrated among the first-degree relatives of probands with a family history of major affective disorders. Conversely, relatives of probands with a family history of schizophrenic 'spectrum' disorders were at a greater risk of affective illness (major depression) than relatives of probands with no family history. These results lend support to the notion that a subset of affective disorders is associated with the liability to schizophrenia.

Drug abuse in schizophrenic patients: clinical correlates and reasons for use

OBJECTIVE

This study aimed to 1) determine substance abuse prevalence and preference in a diverse sample of schizophrenic, schizoaffective, and schizophreniform inpatients, 2) compare drug-abusing and non-drug-abusing patients on demographic and clinical variables during the acute and stabilization phases of their hospital course, and 3) obtain data from patients on reasons for drug abuse and on acute state-related changes during periods of intoxication.

METHOD

Eighty-three psychotic inpatients consecutively admitted to a New York City teaching hospital were evaluated. Sixty-eight had schizophrenia, 12 had schizoaffective disorder, and three had schizophreniform disorder diagnosed according to the Structured Clinical Interview for DSM-III-R. Each patient received ratings on the Brief Psychiatric Rating Scale, the Global Assessment Scale, and the Scale for the Assessment of Negative Symptoms at admission and at discharge, an evaluation of premorbid adjustment, and an extensive interview on drug and alcohol use.

RESULTS

Forty (48%) of the patients received diagnoses of drug or alcohol abuse or dependence. The drug-abusing patients primarily used cannabis (N = 26), alcohol (N = 21), and cocaine (N = 14) and reported that they abused drugs to get "high," to relieve depression, and to relax. They had significantly fewer positive and negative symptoms at discharge, better sexual adjustment and worse school performance during adolescence, and more family histories of drug abuse than the non-drug-abusing patients.

CONCLUSIONS

Schizophrenic patients who abuse drugs may represent a subgroup of patients with better prognoses and less severe clinical characteristics of schizophrenia, but their drug abuse may adversely affect global outcome.

An update on the epidemiology of schizophrenia

This report summarizes research in epidemiology and related areas which addresses as yet unresolved issues in schizophrenia. These include the nature of the disorder, environmental and psychosocial risk factors and differences in the course of illness. Unravelling the complexities of etiology, course and appropriate treatment calls for an integration of biological and psychosocial paradigms. The review also illustrates that a broad-based view can generate fruitful hypotheses as well as important alternative explanations for research findings.

Pimozide in pathological jealousy

A 39-year-old man had his pathological jealousy successfully treated with pimozide. It is suggested that pimozide might be considered the drug of choice in all the monodelusional disorders.

Long-term course and outcome in delusional disorder

Out of 301 first-time admitted patients with delusional psychoses, 71 met Kendler's criteria of delusional disorder (DD) and 137 met the ICD-9 criteria of schizophrenia (S). DD was subdivided according to operational criteria into reactive delusional disorder (RDD) with precipitating factors (n = 31) and non-RDD (n = 40). At follow-up after 22-39 years, 20 RDD patients, 21 non-RDD patients and 85 S patients were personally interviewed. The delusions had faded in 61% of DD cases, were unchanged in 17%, and more prominent in another 17%. Recovery was recorded in 37%, mild defect in 32%, moderate impairment in 10%, and severe impairment in 22% of DD patients. Outcome was more favourable in DD compared with S, in RDD compared with non-RDD, and in non-RDD compared with S. The study supports distinctions between DD and S, RDD and non-RDD, and non-RDD and S based on course and outcome.

Delusional (paranoid) disorders

The group of paranoid or delusional disorders, although not nearly as common as the mood and schizophrenic disorders, may be much more frequent than has usually been thought. DSM-IIIR has made a decisive step in recognizably defining at least one group of them. Interestingly, this change partly came about because the advent of an effective treatment helped to define that group more clearly. Nevertheless, DSM-IIIR's classification is too restrictive, and it was wrong to exclude the diagnosis of paraphrenia. Cases fitting this description will have to be consigned to the category of Psychotic Disorder NOS, which will inevitably be a grab-bag of mixed diagnoses. Also, DSM-IIIR does not emphasize the link between the delusional disorders and paranoid schizophrenia, and the somewhat less well defined overlap with affective disorders, both of which give rise to much diagnostic confusion and inappropriate treatment. Precise history taking and mental status examination and, above all, an up-to-date knowledge of their existence are essential to the recognition and appropriate treatment of the delusional disorders.

Delusional (paranoid) disorders: etiologic and taxonomic considerations. I. The possible significance of organic brain factors in etiology of delusional disorders

The term "Paranoid Disorders" is used vaguely and indiscriminately by many authors. This article provides brief working descriptions of a small number of paranoid/delusional conditions and, making reference to the author's series of monodelusional disorders, describes certain organic brain factors which appear to be surprisingly common in the background of these cases. It is hypothesized that the group of paranoid/delusional disorders may be linked to schizophrenia, especially of the paranoid type: however, in the paranoid/delusional disorders, hereditary schizophrenic factors may be weak and adverse organic brain factors relatively much stronger.

Mania following head injury

A case of mania following head injury in an individual with a genetic predisposition to schizophrenia is reported. It is argued that the head injury is probably causative in his case and suggested that head injury should be considered as one of the aetiological factors in secondary mania.

Delusional disorder in mother and daughter: case report

The occurrence of delusional disorder in a mother-daughter pair is described. The significance of this report is discussed in light of recent family studies of this disorder, and in reference to treatment implications.