Electrodermal activity and social network as predictors of outcome of episodes in schizophrenia

Sources of social support and clinical and functional evolution of people with schizophrenia

PURPOSE

The impact of social support on comprehensive measures of results (clinical and functional) of the course of schizophrenia was studied, understood and evaluated as a multidimensional construct differentiating sources of support (family vs. nonfamily).

METHODS

One hundred fifty-two patients diagnosed with schizophrenia were assessed with the Mannheim Interview on Social Support (MISS) and the Social Functioning Scale (SFS). The hypotheses were explored in a prospective longitudinal design, using a causal correlational analysis for their evaluation by applying structural equation models.

RESULTS

The only explanatory factor of social functioning was Nonfamily social support, while the only explanatory factor of clinical result measurements was Family social support, observing a clearly differentiated impact of the different sources of support on the schizophrenia result measurements. It was also found that while Family social support explained 6.8% of the variance in the clinical result measurements, Nonfamily social support explained 13.7% of the variance in social functioning.

CONCLUSION

The results confirmed the differential importance of social support variables (family vs. nonfamily) in the clinical and functional result measurements of people with schizophrenia.

Social support and clinical and functional outcome in people with schizophrenia

PURPOSE

The impact of Social Support (SS) on the clinical and functional evolution of patients diagnosed with schizophrenia was studied from a multidimensional concept of SS in the framework of the vulnerability-stress model.

METHODS

In total, 152 patients diagnosed with schizophrenia according to the International Classification of Diseases, Tenth Edition (ICD-10) treated in a Community Mental Health Unit were assessed using the Mannheim Interview on Social Support (MISS) and the Brief Psychiatric Rating Scale (BPRS). Then they were followed up for 3 years with a final assessment for the period using the Social Functioning Scale. The impact of SS was explored in clinical and functional measurements with a multiple regression analysis in a 3-year longitudinal prospective design.

RESULTS

The quality of Global Social Support (GSS) and satisfaction with GSS appeared to be protective factors from frequency and duration of hospital admissions, with explanatory intensity varying from 9% in survival time to relapse to 13% in number of relapses. Concerning functional measurements, GSS quantity, quality and satisfaction showed an explanatory power for several different dimensions of social functioning, varying from 12% in isolation to 20% in communication.

CONCLUSION

The results confirm SS as a protective factor in the evolution of schizophrenia patients and enable the SS variables with the most explanatory power in their clinical and functional evolution to be identified.

Social relationships in young adults at ultra high risk for psychosis

Studies suggest that individuals with schizophrenia have smaller social networks and less satisfying relationships. However, much is still unknown about the typical quantity and quality of social relationships in young adults during the ultra high-risk (UHR) period. Investigating these relationships holds significant importance for improving understanding of etiological processes, mapping the social environment, and highlighting treatment targets in a critical period. A total of 85 participants (44 UHR and 41 healthy controls) completed measures examining the participants' social relationships, social support, and loneliness. Mean differences between the UHR and healthy control participants and associations between social relationships and symptoms and functioning were examined. Results indicated significant differences between groups on several indices. Specifically, the UHR youth reported fewer close friends, less diverse social networks, less perceived social support, poorer relationship quality with family and friends, and more loneliness. Notably, within the UHR group, being lonely and having fewer and worse quality relationships was associated with greater symptom severity and lower overall functioning. This study suggests that youth at high-risk of developing psychosis have fewer and poorer quality social relationships. Interventions that focus on increasing the quantity and quality of young adults' social networks may be beneficial for this population.

Cognition and autonomic function in schizophrenia: inferior cognitive test performance in electrodermal and niacin skin flush non-responders

BACKGROUND

Patients with schizophrenia suffer from a broad range of cognitive disturbances. The impact in terms of functional outcome is significant. There are also several reports of disturbed autonomic regulation in the disease. The present study examined cognitive function as well as psychophysiological parameters in patients with schizophrenia and healthy controls.

METHODS

Twenty-five patients and 14 controls were investigated with electrodermal activity (EDA), an oral niacin skin flush test and a comprehensive neurocognitive test program including the Wechsler battery (WAIS-R), Fingertapping Test, Trail Making Test, Verbal Fluency, Benton Visual Retention Test, Wisconsin Card Sorting Test and Rey Auditory Verbal Learning Test.

RESULTS

The patients generally had inferior test results compared to controls. Further analysis revealed that the EDA non-responding patient group explained this variation with significant lower test results than controls. On executive tests, EDA non-responders also performed significantly worse than EDA responding patients. The small group of niacin non-responding patients exhibited an even lower overall test performance. Delayed niacin flush also correlated inversely with psychomotor function and IQ in the patients.

CONCLUSION

The findings support the hypothesis of a neurodevelopment disturbance affecting both autonomic function and higher cortical function in schizophrenia.

Test-retest stability of the oral niacin test and electrodermal activity in patients with schizophrenia

In schizophrenia, well-replicated findings support an attenuated niacin skin-flush response. We have previously reported a delayed skin-flush after niacin ingestion and also an association between niacin non-responding and electrodermal non-responding in schizophrenia. The stability of the niacin and electrodermal tests was now studied in a test-retest design. An additional aim was to assess the association previously found. Twenty-three patients with schizophrenia underwent two sessions 3 months apart during which an oral niacin test was conducted and electrodermal activity was measured. Despite similar values for niacin outcome variables at the group level, there was high intraindividual variation. Test-retest stability for the oral niacin test was thus low, although a trend toward correlation for the dichotomous response criterion was found. Most electrodermal measures correlated between baseline and retest. A significant association between the tests was again found; niacin non-responding implied electrodermal non-responding, providing further support for a common underlying aberration in schizophrenia.

Beat-to-beat heart rate and QT interval variability in first episode neuroleptic-naive psychosis

INTRODUCTION

Though increased risk of sudden death in patients with schizophrenia is well-documented, the mechanisms remain unclear. Recent studies report two known risk factors for sudden cardiac death and other arrhythmias in schizophrenia, i.e., decreased RR interval variability (RRV) and increased QT interval variability (QTV). However, these studies did not control for the effects of medication. Herein, we report the results of our study comparing RRV and QTV in first episode neuroleptic-naive psychosis patients with healthy matched controls.

METHODS

24 patients with first episode neuroleptic naïve psychosis were matched with 26 healthy controls on age and gender. After an overnight fast, all participants underwent an electrocardiogram recording in the morning.

RESULTS

In comparison with matched controls, patients with first episode neuroleptic-naïve psychosis had significantly increased QTV corrected for RRV, and decreased RRV.

CONCLUSIONS

The observed alterations in RRV and QTV may reflect impaired cardiac autonomic function that could underlie risk for abnormal ventricular repolarization and thereby increase the risk of sudden death and other arrhythmias. Our data suggest that RRV and QTV alterations may be independent of medication effects in first episode psychosis patients.

Niacin skin-flush response and electrodermal activity in patients with schizophrenia and healthy controls

Patients with schizophrenia have in different studies shown reduced niacin sensitivity and lower electrodermal activity (EDA) after auditory stimulation. Peripheral mediation of prostaglandins may have a physiological role in both responses. This motivates study of both niacin response and electrodermal responding in the same patients with schizophrenia. Thirty patients with schizophrenia and 17 controls were investigated with EDA and thereafter given 200mg niacin orally with continuous assessment of skin temperature. The patients showed a delayed temperature increase after niacin ingestion (P=0.002) and a higher frequency of electrodermal non-responding (P<0.05). Response/non-response for niacin correlated with EDA response/non-response in the patient group (P=0.009). The niacin test revealed a slower vasodilation reaction in the patients. The association between response patterns for the niacin test and EDA suggests that a common aberration in skin physiology may be of importance for both reactions in schizophrenia.

Electrodermal predictors of functional outcome and negative symptoms in schizophrenia

The ability of electrodermal variables to predict negative symptoms and functional outcome over a 1-year period in schizophrenia was investigated in 78 young, recent-onset outpatients. Patients were stabilized on standardized medication and largely free of psychotic symptoms. Higher levels of both tonic (skin conductance level, nonspecific skin conductance response rate) and phasic (number of skin conductance orienting responses) activity were associated with more negative symptoms and with a combination of poorer social and occupational outcome at 1-year follow-up. This pattern was seen in both male and female patients, and in older and younger patients. Results are interpreted as suggesting that high levels of arousal and overreactivity to the environment may interfere with efficient cognitive processing in schizophrenia, contributing to poor outcome, and that negative symptoms might partially serve as a means of coping with overarousal.

Social network correlates among people with psychiatric disabilities

This study explores three social network characteristics as they relate to demographic, clinical, and quality of life factors. The sample consists of 219 participants with serious mental illness. Results indicate that clients' social networks were small, and that network size is robustly related to symptoms and other measures of clinical and cognitive functioning, as well as with quality of life and self-esteem. The expected relation between network density and either the demographic variables or quality of life was not found. Moderate levels of network density, however, were associated with fewer psychiatric symptoms and higher IQ. Network multiplexity was most highly associated with demographic variables, such as ethnic minority status, less education, never being married, and living with family.

What does electrodermal activity tell us about prognosis in the schizophrenia spectrum?

Various dysfunctions in electrodermal activity (EDA) have been found in schizophrenic patients. The present paper reviews evidence that the electrodermal dysfunctions may carry prognostic information regarding subsequent symptoms, as well as social and occupational outcome. Although the findings are not entirely consistent, heightened electrodermal activity as indicated by frequent orienting responses to innocuous stimuli, elevated skin conductance level (SCL), and frequent non-specific skin conductance responses (NS-SCR) is most often associated with poor symptomatic, social, and occupational outcome in schizophrenic patients. There have been no studies that have directly examined electrodermal prognostic indicators in schizotypal individuals. However, high-risk studies suggest that heightened electrodermal activity may be prognostic of poor outcome in schizotypals as well. Thus, abnormally high electrodermal arousal and reactivity is predictive of poor outcome in at least some patients. The theoretical implications of these findings and directions for further research are briefly discussed.

The relationship between skin conductance hyporesponsivity and perseverations in schizophrenia patients

BACKGROUND

It has been reported that approximately 45% of schizophrenia patients versus 10% of normal comparison subjects are classified as skin conductance hyporesponders (SCOR-HR: the lack of a robust orienting response) when exposed to innocuous tones. We studied the skin conductance orienting response (SCOR) of schizophrenia patients during the exposure to complex and abstract stimuli. We investigated two questions: 1) would the same percentage of schizophrenia patients be classified as SCOR-HR when the orienting stimuli are complex and abstract as when they are innocuous tones; and 2) whether SCOR-HR schizophrenia patients have associated frontally mediated neurocognitive deficits.

METHODS

Thirty-one schizophrenia patients and 29 normal comparison subjects were presented with the Rorschach inkblot test while their SCORs were recorded. Schizophrenics were divided in two groups: SCOR-HR and SCOR responders. Demographic and clinical comparisons were made between the two groups. Rorschach responses were scored for the presence of perseverations.

RESULTS

Forty-five percent of the schizophrenia patients were classified as SCOR-HR versus 10% of the normal comparison subjects. Among the schizophrenia patients, SCOR-HR was associated with increased perseverations, which were in turn correlated with the Scale for the Assessment of Negative Symptoms scores.

CONCLUSIONS

It appears that SCOR-HR in schizophrenia is not a function of the "meaningfulness" of the stimuli. When SCOR status was combined with the measure of stuck-in-set perseverations, a pattern of results emerged lending indirect support to the hypothesis that relates SCOR-HR to frontal impairment and to the idea that SCOR-HR schizophrenia patients may represent a specific subgroup.

Perinatal characteristics and schizophrenia: electrodermal activity as a mediating link in a vulnerability-stress perspective

Vulnerability-stress models of schizophrenia assert that the disorder results from an interaction between genetic or biologically acquired vulnerability and unfavourable environmental conditions. As our knowledge of early environmental factors for schizophrenia evolves, the question of links between early factors and a development of schizophrenia becomes more important. In this article, we analyse the relationship between obstetrical complications (OCs) and adult schizophrenia and methodological concerns in the search for pre- and perinatal risk factors. We review findings of aberrant electrodermal activity in schizophrenic patients and suggest that OCs may induce insults to cerebral structures that are critically involved in the control of orienting and of autonomic responses.