Family history of schizophrenia and the relationship of stress to symptoms: preliminary findings

A systematic review and meta-analysis of the association between emotional stress reactivity and psychosis

AIM

Emotional stress reactivity may be a mediating factor in the association between trauma and psychosis. This review aimed to (i) identify, summarise and critically evaluate the link between emotional stress reactivity and psychotic experiences (ii) examine evidence for a 'dose-response' relationship between stress reactivity and psychosis in the wider psychosis phenotype (i.e., sub-clinical symptoms).

METHODS

Electronic database searches (PsychINFO, MEDLINE, EMBASE) were conducted for studies which investigated the link between stress reactivity and psychosis, psychotic symptoms, or a vulnerability to developing psychosis (wider phenotype). Cross-sectional, experimental and experience sampling method study designs were eligible for inclusion.

RESULTS

Fourty five eligible articles were identified (N participants = 8830). Narrative synthesis showed that increased emotional stress reactivity was associated with psychosis and subclinical psychotic experiences across all study designs, however, findings were inconsistent across studies. The preliminary meta-analysis (k = 4, n = 383) showed increases in emotional stress reactivity was associated with higher negative affect in response to event-related stress, in those with psychosis compared to controls (mean difference in beta coefficients = 0.05, 95% CI 0.02-0.08, p = .004). However, this difference was small with a considerable degree of heterogeneity (p = .001, I²  = 81%) so results should be interpreted with caution.

CONCLUSIONS

Overall, the evidence suggests that there is a link between emotional stress reactivity and psychosis in those with psychosis, those at high risk of developing psychosis and in relation to subclinical psychotic-like experiences in the general population.

Family history of psychosis and outcome of people with schizophrenia in rural China: 14-year follow-up study

OBJECTIVE

This study examined the differences in 14-year outcomes of persons with schizophrenia with and without family history of psychosis in a rural community in China.

METHODS

All participants with schizophrenia (n=510) aged 15 years and older were identified in a 1994 epidemiological investigation of 123,572 people and followed up in 2004 and 2008 in Xinjin County, Chengdu, China.

RESULTS

Individuals with positive family history of schizophrenia had significantly younger age of first onset than those with negative family history of schizophrenia in 1994 and 2004. Compared with individuals with negative family history of schizophrenia, those with positive family history of schizophrenia had significantly higher rate of homelessness and lower rate of death due to other reasons in 10-year (2004) and 14-year follow-up (2008). There were no significantly differences of mean scores on PANSS, SDSS and GAF in 2008 between positive and negative family history groups.

CONCLUSIONS

The positive family history of schizophrenia is strongly related to younger age of onset, and may predict a poorer long-term outcome (e.g., higher rate of homelessness) in persons with schizophrenia in the rural community. The findings have implications for further studies on specific family-related mechanisms on clinical treatment and rehabilitation, as well as for planning and delivering of community-based mental health services.

Ego Functions in Relation to Stressful Life Events and Indices of Psychopathology in Paranoid Schizophrenia

This study explored the role of 12 ego functions in relation to Stressful Life Events and three indices of psychopathology, namely, Psychoticism, Anxiety, and Depression among 60 Bengali adult patients suffering from Paranoid Schizophrenia. Adapted versions of Bellak's Ego Function Assessment–M, Eysenck's Personality Questionnaire, Beck Depression Inventory, and the State-Trait Anxiety Inventory were administered to them. Stepwise multiple regression analyses indicated that Object Relation was associated with all three indices. Scores on Reality Testing correlated with those on Psychoticism, Stressful Life Events and scores on Thought Process with Anxiety, and Stressful Life Events, Sense of Reality, and scores on Defensive Functions with Depression. Hierarchical multiple regression analyses indicated that Object Relation also moderated between stressful life events and anxiety.

Effect of psychosocial environment in children having mother with schizophrenia

The process of child׳s mental development depends heavily on the social interrelationship between the mother and her child. Schizophrenia in mothers potentially disrupts mother-infant relationship and adaptation to motherhood. Literature is limited on evaluating the emotional and behavioral problems of children of mother having schizophrenia with nearly none from the Indian subcontinent. The aim of the current study was to examine the effect of psychosocial environment in children of females with schizophrenia. Thirty children of mothers suffering with schizophrenia were evaluated with Child Behavior Checklist (CBCL) and Mini International Neuropsychiatric Interview for children and adolescents. The psychosocial environment was assessed using Parent Interview Schedule. Control group of 30 children were evaluated in the same way as the cases. The children of female patients with schizophrenia were found to score significantly higher on internalizing and externalizing behavioral problems on CBCL as compared to control group, along with significant differences in the psychosocial environment between the groups. We conclude that there is a need for screening and evaluation of children of mothers diagnosed with schizophrenia, for identifying and managing possible mental and behavioral problems in them, and to assess the psychosocial environment and provide interventions for issues related to it.

Much ado about much: stress, dynamic biomarkers and HPA axis dysregulation along the trajectory to psychosis

OBJECTIVES

In the context of a stress-vulnerability framework, hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis is thought contribute to the risk, onset and course of psychotic illness. However, recent reports regarding static and dynamic features of the HPA axis suggest a more complex set of phenomena at play in the early phases of psychosis.

METHODS

We review literature regarding structural and functional aspects of the HPA axis in subjects at risk for or experiencing the first episode of psychosis, including evidence favoring as well as that which contradicts a model of HPA axis hyperactivation.

RESULTS

Static measures of diurnal cortisol and hippocampal/pituitary volumes suggest that the HPA axis is in a hyperactivated state in early phases of psychosis. In contrast, the dynamic cortisol response to encountered or anticipated stress is blunted in the same populations. These incongruent findings need to be better understood.

CONCLUSIONS

We consider potential explanations for the seemingly contradictory elevation and blunting of HPA biomarkers in the early course of psychosis. Finally, we propose and explore implications of a conceptual model of tonic HPA hyperactivation and phasic HPA blunting that integrates and reconciles these data.

Abnormal immune system development and function in schizophrenia helps reconcile diverse findings and suggests new treatment and prevention strategies

Extensive research implicates disturbed immune function and development in the etiology and pathology of schizophrenia. In addition to reviewing evidence for immunological factors in schizophrenia, this paper discusses how an emerging model of atypical immune function and development helps explain a wide variety of well-established - but puzzling - findings about schizophrenia. A number of theorists have presented hypotheses that early immune system programming, disrupted by pre- and perinatal adversity, often combines with abnormal brain development to produce schizophrenia. The present paper focuses on the hypothesis that disruption of early immune system development produces a latent immune vulnerability that manifests more fully after puberty, when changes in immune function and the thymus leave individuals more susceptible to infections and immune dysfunctions that contribute to schizophrenia. Complementing neurodevelopmental models, this hypothesis integrates findings on many contributing factors to schizophrenia, including prenatal adversity, genes, climate, migration, infections, and stress, among others. It helps explain, for example, why (a) schizophrenia onset is typically delayed until years after prenatal adversity, (b) individual risk factors alone often do not lead to schizophrenia, and (c) schizophrenia prevalence rates actually tend to be higher in economically advantaged countries. Here we discuss how the hypothesis explains 10 key findings, and suggests new, potentially highly cost-effective, strategies for treatment and prevention of schizophrenia. Moreover, while most human research linking immune factors to schizophrenia has been correlational, these strategies provide ethical ways to experimentally test in humans theories about immune function and schizophrenia. This article is part of a Special Issue entitled SI: Neuroimmunology in Health And Disease.

Family history of psychosis negatively impacts age at onset, negative symptoms, and duration of untreated illness and psychosis in first-episode psychosis patients

Family history (FH) of psychosis has been a focus of investigations attempting to explain the heterogeneity in schizophrenia. Previous studies have demonstrated that FH is associated with earlier age at onset, severity of positive and negative symptoms, and the duration of untreated illness (DUI). The current study examined the impact of FH on the clinical presentation and help-seeking behaviors of a well-characterized, first-episode sample. The present study utilized the Symptom Onset in Schizophrenia (SOS) Inventory, the Positive and Negative Syndrome Scale (PANSS), and structured interviews on FH to examine these relationships in a large (n=152) sample of predominantly African American patients. Results showed that patients with a first-degree FH of psychosis had a younger age at onset of both the prodrome and psychosis, but did not differ in duration of prodromal period. Furthermore, FH and sex interacted to influence severity of negative, but not positive symptoms. Finally, FH interacted with sex to influence both the DUI and DUP in that only males with FH had longer DUI and DUP. The findings have implications for understanding the impact of specific family-related mechanisms on both clinical and help-seeking factors, as well as for informing future family-based intervention efforts.

The impact of a family history of psychosis on age-at-onset and positive and negative symptoms of schizophrenia: a meta-analysis

The results of research on the relation of family history (FH) of psychosis with clinical presentation in schizophrenia have been mixed. To date, there have been no comprehensive reviews that have examined this body of research. The current review quantitatively evaluates research on the relation of FH with two aspects of schizophrenia, age-at-onset and symptom presentation. Studies investigating the influence of a FH on age-at-onset (N=15 studies), age-at-onset and sex (N=12 studies), and/or positive (N=11 studies) and negative symptoms (N=12 studies) in patients with schizophrenia were included in the meta-analyses. Results showed that FH has a small but significant impact on age-at-onset as well as negative symptoms. Of most interest was the finding that sex differences in age-at-onset are not observed in samples with a FH. Furthermore, there was a significant interaction between FH and sex with respect to negative symptoms. The findings of the current review are discussed in light of the diathesis-stress model. Theoretical assumptions and empirical research are reviewed to support the notion that FH influences susceptibility and presentation through similar mechanisms. Implications of the current findings, limitations of the review, and directions for future research are highlighted.

A unifying hypothesis of schizophrenia: abnormal immune system development may help explain roles of prenatal hazards, post-pubertal onset, stress, genes, climate, infections, and brain dysfunction

We propose a unifying hypothesis of schizophrenia to help reconcile findings from many different disciplines. This hypothesis proposes that schizophrenia often involves pre- or perinatal exposure to adverse factors that produce a latent immune vulnerability. When this vulnerability is manifested, beginning around puberty with changes in immune function and involution of the thymus, individuals become more susceptible to infections and immune dysfunctions that contribute to schizophrenia. Our hypothesis suggests theoretical bridges between different lines of evidence on schizophrenia and offers explanations for many puzzling findings about schizophrenia. For example, the hypothesis helps account for why schizophrenia patients tend to have had increased exposure to neurotropic infections, but most individuals with such exposure do not develop schizophrenia, and why prenatal hardships increase risk for schizophrenia, but the onset of symptoms typically does not occur until after puberty. The hypothesis also explains another paradox: lower socioeconomic status and poor prenatal care increase risk for schizophrenia at the same geographic site, but international comparisons indicate that countries with higher per capita incomes and better prenatal care actually tend to have higher schizophrenia prevalences. As the hypothesis predicts, (1) prenatal adversity, which increases risk for schizophrenia, also impairs post-pubertal immune competence, (2) schizophrenia patients experience elevated morbidity from infectious and auto-immune diseases, (3) genetic and environmental risk factors for schizophrenia increase vulnerability to these diseases, (4) factors that exacerbate schizophrenic symptoms also tend to impair immune function, (5) many anti-psychotic medications combat infection, (6) effects of early infections may not appear until after puberty, when they can produce neurologic and psychiatric symptoms, and (7) immune dysfunctions, such as imbalances of pro- and anti-inflammatory cytokines, may contribute to the onset of psychotic symptoms and the progressive loss of brain tissue in schizophrenia. The disruptive effects of prenatal adversity on the development of the immune system may often combine with adverse effects on prenatal brain development to produce schizophrenia. This paper focuses on the adverse immune system effects, because effects on the brain have been extensively discussed in neurodevelopmental theories of schizophrenia. We propose new tests of scientific predictions. We also point out potential clinical implications of the hypothesis; for example, individuals with schizophrenia may often have underlying infections or immune dysfunctions, such as imbalances in inflammatory cytokines, that contribute to the illness. This possibility could be tested experimentally--e.g., by clinical trials in which patients' exposure to infection is reduced or immune function is normalized.

Positive family history is associated with persistent elevated emotional distress in schizophrenia: evidence from a 16-month follow-up study

There is some evidence that emotional reactivity to daily life stress is related to a genetic or familial liability to develop schizophrenia. However, it is unclear whether the emotional distress is elevated in schizophrenia patients with positive compared to negative family history. The aim of the study was to test the hypothesis that a persistent higher level of emotional distress in schizophrenia subjects is associated with a positive family history of schizophrenia. This study used the Talbieh Brief Distress Inventory (TBDI), the Positive and Negative Syndrome Scale (PANSS; including dysphoric mood, positive and negative subscales), Montgomery-Asberg Depression Rating Scale (MADRS), and the Distress Scale for Adverse Symptoms (DSAS) to investigate the difference in the magnitude of emotional distress scores between schizophrenia subjects with and without a positive family history of schizophrenia over time. Data were recorded for 69 multiplex family and 79 singleton patients at admission and about 16 months thereafter. No between-group differences were obtained in PANSS and DSAS scores. With regard to the TBDI: (a) both group of patients had no significant differences in emotional distress scores at admission; (b) patients with negative family history reported improvement in distress severity and depression severity (MADRS) 16 months after admission, while those with positive family history experienced persistent elevated emotional distress, mainly, on obsessiveness, and depression subscales; and (c) both groups of patients are characterized by elevated emotional distress at follow-up examination compared to healthy subjects. Thus, it appears that there is a strong association between positive family history and persistent elevated emotional distress. Because patients with positive and negative family history are likely to differ in genetic risk, our results suggest that long-term elevated levels of emotional distress may be related to a familial (environmental)/genetic vulnerability to schizophrenia.

The significance of family history in first-episode schizophrenia spectrum disorder

There have been inconsistent findings regarding the significance of family history of schizophrenia spectrum disorders in relation to presentation and course of illness. There has been little research relevant to this issue from first-episode patients. We examined the differences in premorbid adjustment, symptoms, and intellectual functioning between 28 first-episode schizophrenia spectrum patients with a history of such illness in first degree relatives and 28 matched patients without such a family history. The results indicate that whereas the 2 groups did not differ in presenting symptoms, those with a positive family history showed poorer intellectual functioning and less reduction in symptoms at 2 and 3 year follow-up and greater likelihood of abnormal electroencephalogram findings. The findings provide evidence that presence of a positive family history in first-episode patients is associated with a more pernicious form of illness.

Stressful life events in recent-onset schizophrenia: reduced frequencies and altered subjective appraisals

While research strongly supports the notion that stressful life events may trigger the exacerbation of psychotic symptoms in schizophrenia, the mechanisms through which affected individuals respond to life events during the early course of this disorder have received limited attention. This 12-month longitudinal study compared the frequencies, qualitative characteristics, and subjective appraisals of life events in recent-onset schizophrenia patients (n=78) and a nonpatient comparison sample (n=63). Negative and positive life events were assessed using a semi-structured interview every 4 weeks among patients and approximately every 4 months among controls, and participants appraised each event they experienced in terms of emotional impact, controllability, and effectiveness in handling the event. Schizophrenia patients reported significantly lower rates of life events than their nonpsychiatric counterparts across nearly every type of negative and positive event examined. In the context of generally lower event frequencies, patients appraised the negative and positive events they did experience as less controllable and more poorly handled than controls, and also appraised positive events as less desirable. Results are discussed in terms of their implications for understanding susceptibility to stress during the early course of schizophrenia.