Concurrent measurement of "real-world" stress and arousal in individuals with psychosis: assessing the feasibility and validity of a novel methodology

BACKGROUND

Psychosis has been repeatedly suggested to be affected by increases in stress and arousal. However, there is a dearth of evidence supporting the temporal link between stress, arousal, and psychosis during "real-world" functioning. This paucity of evidence may stem from limitations of current research methodologies. Our aim is to the test the feasibility and validity of a novel methodology designed to measure concurrent stress and arousal in individuals with psychosis during "real-world" daily functioning.

METHOD

Twenty patients with psychosis completed a 36-hour ambulatory assessment of stress and arousal. We used experience sampling method with palm computers to assess stress (10 times per day, 10 AM → 10 PM) along with concurrent ambulatory measurement of cardiac autonomic regulation using a Holter monitor. The clocks of the palm computer and Holter monitor were synchronized, allowing the temporal linking of the stress and arousal data. We used power spectral analysis to determine the parasympathetic contributions to autonomic regulation and sympathovagal balance during 5 minutes before and after each experience sample.

RESULTS

Patients completed 79% of the experience samples (75% with a valid concurrent arousal data). Momentary increases in stress had inverse correlation with concurrent parasympathetic activity (ρ = -.27, P < .0001) and positive correlation with sympathovagal balance (ρ = .19, P = .0008). Stress and heart rate were not significantly related (ρ = -.05, P = .3875).

CONCLUSION

The findings support the feasibility and validity of our methodology in individuals with psychosis. The methodology offers a novel way to study in high time resolution the concurrent, "real-world" interactions between stress, arousal, and psychosis. The authors discuss the methodology's potential applications and future research directions.

Childhood onset diagnoses in a case series of teens at clinical high risk for psychosis

REASONS: Schizophrenia is typically an adult neurodevelopmental disorder that has its antecedents in childhood and adolescence. Little is known about disorders "usually first diagnosed in infancy, childhood and adolescence" (e.g., childhood-onset disorders) in "prodromal" teens at heightened clinical risk for psychotic disorder.

MAIN FINDINGS

Childhood-onset disorders were prevalent in putatively prodromal teens, including anxiety and disruptive disorders, attention-deficit/hyperactivity disorder (ADHD), and, surprisingly, elimination disorders. These may reflect developmental antecedents in psychotic disorders such as schizophrenia.

KEY DATA AND STATISTICS

A case series of 9 teens (ages 13-17) identified as prodromal to psychosis were evaluated with the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version (K-SADS-PL). Childhood-onset diagnoses commonly endorsed (threshold or subthreshold) included ADHD (5/9), oppositional defiant disorder (5/9), enuresis or encopresis (4/9), conduct disorder (2/9), separation anxiety (3/9), and transient tic disorder (2/9). Enuresis was identified in 3 of the 4 older teens (ages 15-17).

MAJOR CONCLUSIONS

An understanding of the childhood-onset disorders that occur in teens at risk for psychotic illnesses, such as schizophrenia, can shed light on the pathophysiology of schizophrenia and potentially inform early identification and intervention.

Incidence of schizophrenia among second-generation immigrants in the jerusalem perinatal cohort

OBJECTIVE

Increased incidence of schizophrenia is observed among some immigrant groups in Europe, with the offspring of immigrants, ie "second-generation" immigrants particularly vulnerable. Few contemporary studies have evaluated the risk of schizophrenia among second-generation immigrants in other parts of the world.

METHODS

We studied the incidence of schizophrenia in relation to parental immigrant status in a population-based cohort of 88 829 offspring born in Jerusalem in 1964-1976. Parental countries of birth were obtained from birth certificates and grouped together as (1) Israel, (2) Other West Asia, (3) North Africa, and (4) Europe and industrialized countries. Cox proportional hazards methods were used in adjusting for sex, parents' ages, maternal education, social class, and birth order.

RESULTS

Linkage with Israel's Psychiatric Registry identified 637 people admitted to psychiatric care facilities with schizophrenia-related diagnoses, before 1998. Incidence of schizophrenia was not increased among second-generation immigrants in this birth cohort, neither overall nor by specific group.

CONCLUSIONS

The difference in risk of schizophrenia among second-generation immigrants in Europe and in this Israeli birth cohort suggests that the nature of the immigration experience may be relevant to risk, including reasons for migration, the nature of entry, and subsequent position in the host country for immigrants and their offspring. Minority status may be of importance as, in later studies, immigrants to Israel from Ethiopia had increased risk of schizophrenia.

Effect of socioeconomic status and parents' education at birth on risk of schizophrenia in offspring

Although it is known that schizophrenia is associated with social class, controversy exists as to the nature of this association. The authors studied the incidence of schizophrenia in relation to social class at birth in a population-based cohort of 88,829 offspring born in Jerusalem in 1964-1976. They constructed a six-point scale to index social class, based on paternal occupation at the time of birth, with each of 108 occupations being ranked by mean education. Cox proportional hazards methods were used in adjusting for sex, parents' ages, duration of marriage and birth order. Linkage with Israel's Psychiatric Registry identified 637 people admitted to psychiatric care facilities with schizophrenia-related diagnoses, before 1998. There was no gradient of risk for schizophrenia associated with social class at birth; however, offspring of fathers in the lowest social class showed a modest increase in risk (adjusted Relative Risk = 1.4; 95% Confidence interval = 1.1-1.8, P = 0.002). These data suggest that in contrast to many other health outcomes, there is not a continuous gradient for increasing schizophrenia with decreasing social class of origin. Instead, a modest increase in risk for schizophrenia was observed only for those born at the bottom of the social ladder.

Childhood trauma and prodromal symptoms among individuals at clinical high risk for psychosis

INTRODUCTION

Numerous studies point to an association between childhood trauma and the later development of psychotic illness. However, little is known about the prevalence of childhood trauma and its relationship to attenuated positive and other symptoms in individuals at heightened clinical risk for psychosis.

METHOD

Thirty clinical high-risk patients (83% male, 43% Caucasian, and with a mean age of 19) were ascertained from the New York metropolitan area and evaluated for prodromal and affective symptoms, and queried regarding experiences of childhood trauma and abuse.

RESULTS

Ninety-seven percent endorsed at least one general trauma experience, 83% reported physical abuse, 67% emotional abuse, and 27% sexual abuse. As hypothesized, total trauma exposure was positively associated with severity of attenuated positive symptoms (in particular grandiosity), an effect primarily accounted for by ethnic minority participants, who reported greater exposure to trauma. Trauma exposure was related to affective symptoms only in the Caucasian subgroup.

CONCLUSIONS

Childhood trauma was commonly self-reported, especially among clinical high-risk patients from ethnic minorities, for whom trauma was related to positive symptoms. Future areas of research include an evaluation of potential mechanisms for this relationship, including neuroendocrine and subcortical dopaminergic function.

Cannabis and Psychosis: What Can Daily Diaries Tell Us About Who is Vulnerable?

The association between cannabis use and the initial development of psychotic symptoms has attracted increased interest over the past decade. In particular, researchers have attempted to elucidate whether cannabis use increases the risk of psychosis among vulnerable individuals or may just represent attempts to self-medicate distressing symptoms. While a growing literature suggests that cannabis use may contribute to the development of psychotic symptoms, these findings are based primarily on retrospective assessments that have limited ability to clarify the temporal link between cannabis use and psychotic symptoms. The authors review the literature regarding the link between cannabis use and psychotic symptoms; point out the limitations associated with retrospective assessments; and discuss advantages of incorporating daily diary methods, such as Experience Sampling Method (ESM), to study cannabis use and symptoms during daily functioning in "real world" environments. The authors also discuss potential future applications of ESM in research and clinical practice that may inform the identification of individuals vulnerable to develop psychotic symptoms, as well as the development of treatments that target this population.

Temporal association of cannabis use with symptoms in individuals at clinical high risk for psychosis

BACKGROUND

Cannabis use is reported to increase the risk for psychosis, but no prospective study has longitudinally examined drug use and symptoms concurrently in clinical high risk cases.

METHOD

We prospectively followed for up to 2 years 32 cases who met research criteria for prodromal psychosis to examine the relationship between substance use and clinical measures.

RESULTS

Cases with a baseline history of cannabis use (41%) were older, but did not differ in clinical measures. Longitudinal assessments showed these cases had significantly more perceptual disturbances and worse functioning during epochs of increased cannabis use that were unexplained by concurrent use of other drugs or medications.

CONCLUSIONS

These data demonstrate that cannabis use may be a risk factor for the exacerbation of subthreshold psychotic symptoms, specifically perceptual disturbances, in high risk cases.

Use of Palm computer as an adjunct to cognitive-behavioural therapy with an ultra-high-risk patient: a case report

AIM

Recently, attempts have been made to develop cognitive-behaviour therapy (CBT) treatment models to target negative symptoms in individuals with schizophrenia, as well as individuals at ultra-high risk (UHR) for psychosis. Successful CBT treatment is founded on active patient participation including completion of homework assignments such as daily logs of activities and experiences. However, these very negative symptoms may themselves hinder the rate of homework assignment completion. We describe a case report of using experience sampling method with a Palm computer as an adjunct to CBT with a female patient at UHR status with predominantly negative symptoms. Our aim was to assess the feasibility and effectiveness of this methodology to improve homework completion and overcome treatment barriers associated with negative symptoms.

METHODS

Over the course of treatment, the patient was provided with a Palm computer to carry with her throughout her daily activities. The Palm computer was pre-programmed to beep randomly 10 times per day (10 a.m.-12 a.m.) over each three-day assessment period to elicit information on daily functioning.

RESULTS

The use of the Palm computer was acceptable to the patient and resulted in a substantial increase in homework completion. This methodology resulted in rich information about the patients' daily functioning and patterns of improvement during treatment. The experience sampling method data were also successfully used in the application of treatment interventions.

CONCLUSION

The findings support the feasibility and effectiveness of using Palm computers as adjunct to CBT with UHR individuals with predominantly negative symptoms. The implications for treatment and future research directions are discussed.

Visual form perception: a comparison of individuals at high risk for psychosis, recent onset schizophrenia and chronic schizophrenia

Schizophrenia has been associated with deficits in visual perception and processing, but there is little information about their temporal development and stability. We assessed visual form perception using the Rorschach Comprehensive System (RCS) in 23 individuals at clinical high risk for psychosis, 15 individuals with recent onset schizophrenia (< or =2 years since onset), and 34 with chronic schizophrenia (> or =3 years since onset). All three groups demonstrated reduced conventional form perception (X+%), as compared with published norms, but did not differ significantly from one another. In contrast, the high-risk group had significantly better performance on an index of clarity of conceptual thinking (WSUM6) compared to the chronic schizophrenia patients, with the recent onset group scoring intermediate to the high-risk and chronic schizophrenia groups. The results suggest that individuals at clinical high risk for psychosis display substantial deficits in visual form perception prior to the onset of psychosis and that these deficits are comparable in severity to those observed in individuals with schizophrenia. Therefore, visual form perception deficits may constitute a trait-like risk factor for psychosis in high-risk individuals and may potentially serve as an endophenotype of risk for development of psychosis. Clarity of conceptual thinking was relatively preserved among high-risk patients, consistent with a relationship to disease expression, not risk. These deficits are discussed in the context of the putative neurobiological underpinnings of visual deficits and the developmental pathophysiology of psychosis in schizophrenia.

Validity of a 'proxy' for the deficit syndrome derived from the Positive And Negative Syndrome Scale (PANSS)

Schizophrenia patients with the deficit syndrome (DS) may represent a homogeneous subgroup. To increase the practicability of diagnosing the DS, Kirkpatrick et al. [Kirkpatrick, B., Buchanan, RW., Breier, A. Carpenter, WT., 1993. Case identification and stability of the deficit syndrome of schizophrenia. Psychiatry Res. 47, 47-56.] proposed the use of a 'proxy' case identification tool using standardized symptom ratings instead of the Schedule for the Deficit Syndrome (SDS) which requires an independent clinical assessment. The Proxy for the Deficit Syndrome (PDS) is based on the extraction of symptoms that are essentially equivalent or overlap substantially with the restricted affect and diminished emotional range on the SDS. Kirkpatrick et al. [Kirkpatrick, B., Buchanan, RW., Breier, A. Carpenter, WT., 1993. Case identification and stability of the deficit syndrome of schizophrenia. Psychiatry Res. 47, 47-56.] reported good sensitivity and specificity in a comparison of SDS and PDS assessments among 100 chronic schizophrenia outpatients. The present investigation involves the comparison of the deficit syndrome as assessed by the "gold standard" Schedule for the Deficit Syndrome with the ratings of the same symptoms embodied in the "proxy instrument" the PANSS, within the same group of 156 inpatients. Forty-four patients were assessed by the SDS to have the deficit syndrome. Patients with and without the DS, as defined by the SDS, did not differ for age, education, age at illness onset and duration of illness. The two main 'proxy' measures PDS1 and PDS2 discriminated across the SDS groups. The direct dichotomous comparison of the actual SDS and the 'proxy' derived PDS groups demonstrated good specificity (78.6% and 79.5%) and moderate to very good sensitivity (61.4% and 86.4%) and there was a moderately low rate of false positive cases (21.4% and 20.5%). For the two main 'proxy' measures (PDS1 and PDS2) kappas were .38 and .59, representing poor to good agreement. In our sample of rigorously diagnosed schizophrenia inpatients, the use of a 'proxy' case identification tool for the deficit syndrome would appear to be a viable alternative in identifying a subgroup of schizophrenia patients with the deficit syndrome when the use of the actual SDS is not feasible. Further study is indicated before the PDS as extracted from the PANSS can be used in lieu of the SDS for identifying patients with this syndrome.

Maternal household crowding during pregnancy and the offspring's risk of schizophrenia

BACKGROUND

Animal models of schizophrenia suggest a link between maternal crowding during pregnancy and increased risk of the offspring to develop physiological, developmental, and behavioral abnormalities that are comparable to those observed in schizophrenia. We tested the hypothesis that a similar link is present in humans.

METHOD

We investigated whether prenatal exposure to household crowding was associated with the risk of schizophrenia in a sub-cohort of the Jerusalem Perinatal Study (JPS) consisting 11,015 individuals born between 1964 and 1976. During these years mothers participated in face to face interviews in early pregnancy. The prenatal and birth data, including the number of rooms and individuals living in the mothers' household, was cross-linked with the Israel Psychiatric Registry by ministry personnel.

RESULTS

104 schizophrenia cases were identified in the cohort. Offspring who, while in utero, their mother resided in a household with five or more individuals had RR of 1.47 (95% CI: 0.99-2.16, p=0.05) to develop schizophrenia, compared to those whose mother resided with four or fewer individuals. However, when adjusted for paternal age, the RR was reduced to 1.18 (95% CI: 0.76-1.84, p=0.46). The number of rooms in the household and the household crowding during pregnancy did not significantly impact the offspring's risk to develop schizophrenia.

CONCLUSION

The link between maternal household crowding during pregnancy and the offspring's risk of schizophrenia was explained primarily by the impact of paternal age. The authors discuss the results in view of findings from animal and human studies.

Computerized experience sampling method (ESMc): assessing feasibility and validity among individuals with schizophrenia

The Experience Sampling Method (ESM) is an ecologically valid, time-sampling of self-reports developed to study the dynamic process of person-environment interactions. ESM with digital wristwatch and booklets (paper-based ESM; ESMp) has been used extensively to study schizophrenia. The present study is designed to test the feasibility and validity of using Computerized ESM (ESMc) among individuals with schizophrenia. ESMc is advantageous in allowing for recording of precise time-stamps of responses. We used PDAs ("Personal Digital Assistant"; Palm handheld computers) to collect data on momentary psychotic symptoms, mood, and thoughts over a one day period among 10 hospitalized schizophrenia patients and 10 healthy controls. ESMc was equally acceptable to both groups, with similar ratings of comfort carrying the PDAs and operating them, interference with daily activities, as well as response rates. The schizophrenia patients reported significantly higher ratings of auditory and visual hallucinations, suspiciousness, sense of unreality, lack of thought control, fear of losing control, difficulty expressing thoughts, as well as depression/sadness, loneliness and less cheerfulness. Significant inverse relationships were found among both groups between ratings of feeling cheerful and being stressed, irritated, and sad/depressed. Among the schizophrenia subjects, the correlation between ratings of suspiciousness on ESMc and Scale for Assessment of Positive Symptoms (SAPS) approached significance, as well as the link between suspiciousness and stress. Our results support the feasibility and validity of using ESMc for assessment of momentary psychotic symptoms, mood, and experiences among individuals with schizophrenia. The authors discuss the potential applications of combining ESMc with ambulatory physiological measures.

The factorial structure of the schedule for the deficit syndrome in schizophrenia

Deficit schizophrenia (DS) is considered a distinct subtype within the diagnosis of schizophrenia. While the common assumption is that DS represents a single, cohesive domain of psychopathology, the factorial structure of DS has not been investigated. We assessed 52 individuals with DSM-IV diagnoses of schizophrenia with DS. A principal component analysis (PCA) was conducted on the symptoms of the Schedule for the Deficit Syndrome. The PCA resulted in 2 distinct factors explaining 73.8% of the variance. Factor 1 (avolition) is made up of symptoms of curbing of interests, diminished sense of purpose, and diminished social drive. Factor 2 (emotional expression) is made up of symptoms of restricted affect, diminished emotional range, and poverty of speech. The results indicate that DS is best characterized by these 2 factors. The great majority of participants (86%) displayed DS symptoms from both factors. On average, participants had 4.19 (S.D. = 1.39) symptoms that were primary, enduring, and at least moderate in severity. The mean severity of symptoms was 2.25 (S.D. = 1.06). We discuss possible links between the obtained factors and putative neurobiological mechanisms, as well as directions for future research.

Delusions in individuals with schizophrenia: factor structure, clinical correlates, and putative neurobiology

BACKGROUND

Delusions are a central feature of schizophrenia, yet our understanding of their neurobiology is limited. Attempt to link dimensions of psychopathology to putative neurobiological mechanisms depends on careful delineation of symptoms. Previous factor analytic studies of delusions in schizophrenia were limited by several methodological problems, including the use of patients medicated with antipsychotics, inclusion of nondelusion symptoms in the analyses, and/or inclusion of patients with psychotic disorders other than schizophrenia. These problems may have possibly biased the resulting factor structure and contributed to the inconclusive findings regarding the neurobiology of positive symptoms. Our goal is to examine the factor structure of delusions in antipsychotic-free individuals with diagnoses of schizophrenia/schizoaffective disorder.

SAMPLING AND METHODS

We assessed 83 antipsychotic-free individuals with DSM-IV diagnoses of schizophrenia/schizoaffective disorder. A principal component analysis was conducted on the delusions symptoms of the SAPS.

RESULTS

The principal component analysis resulted in three distinct and interpretable factors explaining 58.3% of the variance. The Delusions of Influence factor was comprised by delusions of being controlled, thought withdrawal, thought broadcasting, thought insertion, and mind reading. The Self-Significance Delusions factor was comprised by delusions of grandeur, reference, religious, and delusions of guilt/sin. The Delusions of Persecution factor was comprised solely by persecutory delusions. The three factors displayed distinct associations with hallucinations, bizarre behavior, attention, positive formal thought disorder, and avolition/apathy.

CONCLUSIONS

The results indicate that delusions are best described by three distinct subtypes. The authors propose a novel model linking the three delusion subtypes, attributions to self/other, and putative neurobiological mechanisms. Implications for future research are discussed, as well as links to cognitive-behavioral conceptualizations of delusions.

The utility of mandatory depression screening of dementia patients in nursing homes

OBJECTIVE

Current methods for enhancing the recognition and treatment of depression in nursing home patients have been unsuccessful. This study examines the process, outcome, and impact of instituting a mandatory depression screening program for depressed dementia patients in nursing homes.

METHOD

The experimental and comparison groups each consisted of two nursing homes of 519 and 363 patients, respectively. Two of the experimental group and one of the comparison group homes were more traditionally staffed facilities; one of the comparison group homes had an enriched staff of psychologists. The Cornell Scale for Depression in Dementia was administered to the residents with dementia. In the experimental group, the patients who scored > or =5 were referred for psychiatric assessment.

RESULTS

In the experimental group, 100% of the referred dementia patients who met screening criteria for depression were seen by a psychiatrist. This resulted in a significant increase in the percentage of individuals given antidepressants. This was greater than the percentage of patients receiving antidepressants in the "typical" comparison group home but not the "staff-enriched" comparison group home. White patients were significantly more likely to receive antidepressants; however, screening significantly increased the proportion of depressed nonwhites receiving antidepressants. At the 12-week follow-up, there was a significant difference in scores between patients receiving antidepressants in each group.

CONCLUSIONS

Mandatory depression screening can significantly increase the proportion of depressed dementia patients receiving antidepressants, lead to dose adjustments, diminish potential ethnic biases in treatment, and affect the depressive symptoms of treated individuals.

Suicide attempts in schizophrenia: the role of command auditory hallucinations for suicide

BACKGROUND

We examined the presence of command auditory hallucinations for suicide (CAHS) in a sample of individuals with schizophrenia or schizoaffective disorder. We examined the relationship between CAHS and demographic and clinical variables. We also investigated the relationship between CAHS and suicide attempts.

METHOD

100 individuals with DSM-IV schizophrenia or schizoaffective disorder hospitalized on an inpatient research unit participated. Information was gathered using the Diagnostic Interview for Genetic Studies and the Harkavy Asnis Suicide Scale. Data were gathered from 1995 to 2001.

RESULTS

CAHS were frequent in this sample (22%), as were suicide attempts (33%). Eight percent of the entire sample (36% of those who experienced CAHS) made at least 1 suicide attempt in response to the hallucinations. The presence of CAHS was not related to demographic or clinical measures assessed. The frequency of CAHS was not statistically different for suicide attempters (30%) and nonattempters (18%). However, 80% (8/10) of attempters with CAHS reported at least 1 attempt in response to CAHS. Three of 6 repeat attempters who made at least 1 suicide attempt in response to CAHS also made other attempts that were not in response to CAHS. The presence of CAHS was not associated with a history of depression or substance abuse/dependence.

CONCLUSION

The presence of CAHS does not directly predict suicide attempts. However, individuals who are already at risk for suicidal behavior (e.g., past attempters) may be at increased risk for a suicide attempt when experiencing CAHS.