The prevalence of potentially traumatic events in the seventh survey of the population-based Tromsø study (Tromsø 7)

Aims: Potentially traumatic events (PTEs) can have detrimental consequences for an individual's physical and mental health. Exposure to PTEs is therefore increasingly assessed in population-based studies. Consistent with this trend, the most recent wave of the longitudinal population-based Tromsø study (Tromsø 7) in Northern Norway included a list of PTEs. The aim of the present study was to describe the prevalence of PTEs in the sample and examine demographic correlates of reported PTE exposure in this group. Methods: In Tromsø 7, a total of 21,083 participants aged ⩾40 years (52.5% female, mean age 57.3 years) were asked about exposure to nine PTEs that occurred in childhood, in adulthood and in the previous year. Differences between demographic groups in exposure to PTEs were examined using chi-square tests and logistic regression analyses. Results: Overall, 67% of the participants reported at least one PTE across the three time intervals. A life-threatening illness or serious accident of a loved one (36.8%) or of the respondent (24.0%) and bullying (21.5%) were the most frequently reported PTEs. Female sex, younger age, indigenous or immigrant ethnicity and higher education were associated with an increased likelihood of reporting at least one PTE. Group differences with respect to specific PTEs were observed. Conclusions: The experience of PTEs is common among the participants in the Tromsø 7 study. The current study lays the foundation for further research into the associations between PTEs and physical and mental health within the Tromsø study.

Associations between stressful life events in childhood/adolescence and adulthood: results from the 7th Tromsø survey

BACKGROUND

Exposure to highly stressful life events (SLEs), such as accidents, violence, or serious illness, is common. With the accumulation of SLEs, the risk of detrimental somatic and mental health outcomes increases. To understand patterns of SLE exposure, research into the associations between SLEs is needed.

METHOD

The sample comprised 21,069 participants of the population-based Tromsø7 (2015/2016) study (52.7% female, mean age = 57.3 years, SD = 11.4 years). Participants were asked whether they had experienced eleven SLEs in childhood/adolescence and adulthood. Correlations, network analysis, and logistic regression analysis were used to examine the associations between SLEs.

RESULTS

Medium-sized to large correlations between SLEs in childhood/adolescence and SLEs in adulthood were found. Two clusters of SLEs emerged in the network analysis in childhood/adolescence and in adulthood, respectively, interpreted as interpersonal (e.g. violence and sexual abuse) and impersonal SLEs (e.g. a life-threatening illness or serious accident). SLEs in childhood/adolescence predicted the number of SLEs in adulthood as well as exposure to the specific SLE categories in adulthood. Childhood neglect was an important predictor of SLE exposure in adulthood.

CONCLUSIONS

Public health policies should focus on the prevention of SLEs and the early intervention after SLE exposure, especially childhood neglect.

Long-term effectiveness and trajectories of change after treatment with SMART, a transdiagnostic CBT for adolescents with emotional problems

Background

There is a need for long-term effectiveness trials of transdiagnostic treatments. This study investigates the effectiveness and diagnosis-specific trajectories of change in adolescent patients attending SMART, a 6-week transdiagnostic CBT for anxiety and depression, with 6-month follow-up.

Methods

A randomized controlled trial with waiting list control (WLC) was performed at three child and adolescent mental health outpatient services (CAMHS) in Norway. Referred adolescents (N = 163, age = 15.72, 90.3% females) scoring 6 or more on the emotional disorders subscale of the Strengths and Difficulties Questionnaire (SDQ) were randomly assigned to treatment or to WLC. Long-term follow-up (N = 83, baseline age = 15.57, 94% females) was performed 6 months after treatment completion (Mean = 7.1 months, SD = 2.5). Linear mixed model analysis was used to assess time by group effects in patients with no diagnosis, probable anxiety, depressive disorder, and combined anxiety and depressive disorder.

Results

Almost one third (31%) obtained full recovery according to the inclusion criterium (SDQ emotional). There was highly significant change in all outcome variables. Effect sizes (ES) were largest for general functioning, measured with CGAS (ES: d = 2.19), and on emotional problems measured with SDQ (ES: d = 2.10), while CORE-17, BDI-II and CGAS all obtained ES’s close to 1. There were no significant time by diagnostic group interactions for any outcomes, indicating similar trajectories of change, regardless of diagnostic group. Waiting 6 weeks for treatment had no significant impact on long-term treatment effects.

Limitations

Possible regression to the mean. Attrition from baseline to follow-up.

Conclusions

Six weeks of transdiagnostic treatment for adolescents with emotional problems showed highly significant change in emotional symptoms and functioning at 6-month follow-up. Patients with anxiety, depression, combined anxiety and depression, and emotional problems with no specific diagnoses, all had similar trajectories of change. Hence this transdiagnostic SMART treatment can be recommended for adolescent patients with symptoms within the broad spectrum of emotional problems.

Trial registration: ClinicalTrials.gov Identifier: NCT02150265. First registered May 29, 2014.

Attitudes Towards the Use of Routine Outcome Monitoring of Psychological Therapies Among Mental Health Providers: The EBPAS-ROM

Implementation of routine outcome monitoring (ROM) in mental health care is progressing slowly. Knowledge about factors influencing ROM implementation, including health providers' attitudes towards ROM, is necessary. Based on a survey of 662 psychologists and nurses, this article describes (1) the development of a short instrument measuring provider attitudes towards ROM, derived from the Evidence-based Practice Attitude Scale (EBPAS), and (2) how attitudinal domains relate to clinicians' current use of standardized instruments for treatment evaluation. The EBPAS-ROM showed concurrent validity in predicting aspects important for the implementation of ROM, including perceived limitations and the value of organizational support.

CORE-OM as a routine outcome measure for adolescents with emotional disorders: factor structure and psychometric properties

Background

Instruments for monitoring the clinical status of adolescents with emotional problems are needed. The Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) according to theory measures problems/symptoms, well-being, functioning and risk. Documentation of whether the theoretical factor structure for CORE-OM is applicable for adolescents is lacking.

Methods

This study examined the factor structure and psychometric properties of the CORE-OM based on two samples of adolescents (age 14–18): youths seeking treatment for emotional problems (N = 140) and high school students (N = 531). A split half approach was chosen. An exploratory factor analysis (EFA) was performed on the first half of the stratified samples to establish the suitability of the model. A Confirmatory Factor Analysis (CFA) with the chosen model from the EFA was performed on the second half. Internal consistency and clinical cut-off scores of the CORE-OM were investigated.

Results

The best fitting model only partially confirmed the theoretical model for the CORE-OM. The model consisted of five factors: 1) General problems, 2) risk to self, 3) positive resources 4) risk to others and 5) problems with others. The clinical cut-off score based on the all-item total was higher than in an adult sample. Both the all-item total and general problems cut-off scores showed gender differences.

Conclusion

The factor analysis on CORE-OM for adolescents resulted in a five-factor solution, and opens up for new subscales concerning positive resources and problems with others. A 17-item solution for the general problems/symptoms scale is suggested. We advise developers of self-report instruments not to reverse items, if they do not intend to measure a separate factor, since these seem to affect the dimensionality of the scales. Comparing means for gender in non-clinical samples should not be done without modification of the general emotional problem and the positive resources scales. Slightly elevated CORE-OM scores (up to 1.3) in adolescents may be normal fluctuations.

A randomized controlled trial of a six-session cognitive behavioral treatment of emotional disorders in adolescents 14-17 years old in child and adolescent mental health services (CAMHS)

Background

This study aims to investigate effectiveness of a 6-week, transdiagnostic cognitive behavioral therapy (CBT) for anxiety and depression in adolescents, the Structured Material for Therapy (SMART), in naturalistic settings of child and adolescent mental health outpatient services (CAMHS).

Methods

A randomized controlled trial with waiting list control (WLC) was performed at three community CAMHS in Norway. Referred adolescents (N = 163, age = 15.72, 90.3% girls) scoring 6 or more on the emotional disorders subscale of the Strengths and Difficulties Questionnaire (SDQ) were randomly assigned to SMART or to WLC.

Results

In the treatment group (CBT), 32.9% improved in the main outcome measure (SDQ), compared to 11.6% in the WLC. Clinically significant and reliable change was experienced by 17.7% in the CBT condition, compared to 5.8% in the WLC. No patients deteriorated. Statistically significant treatment effects were achieved for internalization symptoms, anxiety symptoms and general functioning.

Conclusions

These promising findings indicate that SMART may be considered as a first step in a stepped care model for anxiety and/or depression treatment in CAMHS. The recovery rates imply that further investigations into the effectiveness of brief treatments should be made. Furthermore, there is a need for more comprehensive second-stage treatments for some of these patients.

Trial registration

ClinicalTrials.gov Identifier: NCT02150265. First registered May 292,014.

The Evidence-based Practice Attitude Scale-36 (EBPAS-36): a brief and pragmatic measure of attitudes to evidence-based practice validated in US and Norwegian samples

Background

Short and valid instruments for measuring factors facilitating or hindering implementation efforts are called for. This article describes (1) the adaptation of a shorter version of the Evidence-based Practice Attitude Scale (EBPAS-50 items), and (2) the psychometric properties of the shortened version in both US and Norwegian data.

Methods

The US participants were mental health service providers (N = 418) recruited from clinics providing mental health services in San Diego County, California. The Norwegian participants were psychologists, psychiatric nurses, and psychology students (N = 838) recruited from the Norwegian Psychological Association and the Norwegian Nurses Organization. A confirmatory factor analysis (CFA) approach was used.

Results

The reduction resulted in 36 items named EBPAS-36, and the original 12 factor model was maintained. The EBPAS-36 had acceptable model fit, as indicated by a low degree of misspecification errors in both the US (RMSEA = .045 (CI_90% .040–.049); SRMR = .05) and the Norwegian data (RMSEA = .052 (CI_90% .047–.056, SRMR = .07). Incremental model fit was fair in the US (CFI = .93, TLI = .91) and in the Norwegian samples (CFI = .91, TLI = .89). The internal consistency (Cronbach’s α) in the US and the Norwegian samples were good for the total EBPAS-36 score (.79 and .86, respectively) and were ranged from adequate to excellent for the subscales (US .60–.91 and Norway .61–.92).

Conclusions

The EBPAS-36 has adequate psychometric properties both in US and Norwegian samples, hence indicating cross-cultural validity. It is a brief, pragmatic, and more user-friendly instrument than the EBPAS-50, yet maintains a broad scope by retaining the original 12 measurement domains.

Electronic supplementary material

The online version of this article (doi:10.1186/s13012-017-0573-0) contains supplementary material, which is available to authorized users.

A school intervention for mental health literacy in adolescents: effects of a non-randomized cluster controlled trial

Background

“Mental health for everyone” is a school program for mental health literacy and prevention aimed at secondary schools (13–15 yrs). The main aim was to investigate whether mental health literacy, could be improved by a 3-days universal education programme by: a) improving naming of symptom profiles of mental disorder, b) reducing prejudiced beliefs, and c) improving knowledge about where to seek help for mental health problems. A secondary aim was to investigate whether adolescent sex and age influenced the above mentioned variables. A third aim was to investigate whether prejudiced beliefs influenced knowledge about available help.

Method

This non-randomized cluster controlled trial included 1070 adolescents (53.9% boys, M age14 yrs) from three schools in a Norwegian town. One school (n = 520) received the intervention, and two schools (n = 550) formed the control group. Pre-test and follow-up were three months apart. Linear mixed models and generalized estimating equations models were employed for analysis.

Results

Mental health literacy improved contingent on the intervention, and there was a shift towards suggesting primary health care as a place to seek help. Those with more prejudiced beleifs did not suggest places to seek help for mental health problems. Generally, girls and older adolescents recognized symptom profiles better and had lower levels of prejudiced beliefs.

Conclusions

A low cost general school program may improve mental health literacy in adolescents. Gender specific programs and attention to the age and maturity of the students should be considered when mental health literacy programmes are designed and tried out. Prejudice should be addressed before imparting information about mental health issues.

The factor structure and psychometric properties of the Clinical Outcomes in Routine Evaluation--Outcome Measure (CORE-OM) in Norwegian clinical and non-clinical samples

BACKGROUND

The Clinical Outcomes in Routine Evaluation--Outcome Measure (CORE-OM) is a 34-item instrument developed to monitor clinically significant change in out-patients. The CORE-OM covers four domains: well-being, problems/symptoms, functioning and risk, and sums up in two total scores: the mean of All items, and the mean of All non-risk items. The aim of this study was to examine the psychometric properties of the Norwegian translation of the CORE-OM.

METHODS

A clinical sample of 527 out-patients from North Norwegian specialist psychiatric services, and a non-clinical sample of 464 persons were obtained. The non-clinical sample was a convenience sample consisting of friends and family of health personnel, and of students of medicine and clinical psychology. Students also reported psychological stress. Exploratory factor analysis (EFA) was employed in half the clinical sample. Confirmatory (CFA) factor analyses modelling the theoretical sub-domains were performed in the remaining half of the clinical sample. Internal consistency, means, and gender and age differences were studied by comparing the clinical and non-clinical samples. Stability, effect of language (Norwegian versus English), and of psychological stress was studied in the sub-sample of students. Finally, cut-off scores were calculated, and distributions of scores were compared between clinical and non-clinical samples, and between students reporting stress or no stress.

RESULTS

The results indicate that the CORE-OM both measures general (g) psychological distress and sub-domains, of which risk of harm separates most clearly from the g factor. Internal consistency, stability and cut-off scores compared well with the original English version. No, or only negligible, language effects were found. Gender differences were only found for the well-being domain in the non-clinical sample and for the risk domain in the clinical sample. Current patient status explained differences between clinical and non-clinical samples, also when gender and age were controlled for. Students reporting psychological distress during last week scored significantly higher than students reporting no stress. These results further validate the recommended cut-off point of 1 between clinical and non-clinical populations.

CONCLUSIONS

The CORE-OM in Norwegian has psychometric properties at the same level as the English original, and could be recommended for general clinical use. A cut-off point of 1 is recommended for both genders.

Classification of bipolar disorder in psychiatric hospital. A prospective cohort study

BACKGROUND

This study has explored the classification of bipolar disorder in psychiatric hospital. A review of the literature reveals that there is a need for studies using stringent methodological approaches.

METHODS

480 first-time admitted patients to psychiatric hospital were found eligible and 271 of these gave written informed consent. The study sample was comprised of 250 patients (52%) with hospital diagnoses. For the study, expert diagnoses were given on the basis of a structured diagnostic interview (M.I.N.I.PLUS) and retrospective review of patient records.

RESULTS

Agreement between the expert's and the clinicians' diagnoses was estimated using Cohen's kappa statistics. 76% of the primary diagnoses given by the expert were in the affective spectrum. Agreement concerning these disorders was moderate (kappa ranging from 0.41 to 0.47). Of 58 patients with bipolar disorder, only 17 received this diagnosis in the clinic. Almost all patients with a current manic episode were classified as currently manic by the clinicians. Forty percent diagnosed as bipolar by the expert, received a diagnosis of unipolar depression by the clinician. Fifteen patients (26%) were not given a diagnosis of affective disorder at all.

CONCLUSIONS

Our results indicate a considerable misclassification of bipolar disorder in psychiatric hospital, mainly in patients currently depressed. The importance of correctly diagnosing bipolar disorder should be emphasized both for clinical, administrative and research purposes. The findings questions the validity of psychiatric case registers. There are potential benefits in structuring the diagnostic process better in the clinic.

The relationship between internalizing and externalizing symptoms and cultural resilience factors in Indigenous Sami youth from Arctic Norway

OBJECTIVES

To examine whether enculturation factors, like cultural activities, ethnic pride and native language competence, are related to decreased internalizing and externalizing symptoms in Indigenous Sami youth from Arctic Norway. The impact of self-efficacy on the relationship between enculturation factors and mental health problems was also examined.

STUDY DESIGN

Population-based, cross-sectional questionnaire study.

METHODS

The Norwegian Arctic Adolescent Health Study was conducted among 10th graders in junior high schools in north Norway during 2003-2005. The study sample consisted of 450 Indigenous Sami youth, aged 15-16 years. Internalizing symptoms were measured with the Hopkins Symptom Check List-10 (HSCL-10), while externalizing symptoms were measured by two subscales of the Strengths and Difficulties Questionnaire (SDQ).

RESULTS

For boys, self-efficacy and participation in cultural activities were associated with decreased internalizing symptoms. Additionally, self-efficacy interacted with Sami language competence and cultural activities: when self-efficacy increased, these enculturation factors were related to symptom reduction. For girls, self-efficacy had an independent effect on internalizing symptoms and also strengthened the relationship between participation in cultural activities and reduced externalizing symptoms. Sami language competence was related to the reduction of both internalizing and externalizing symptoms in girls.

CONCLUSIONS

In the present study, several enculturation factors as well as self-efficacy were identified as potential protective factors against mental health problems. In order to develop theoretical models that explain the mechanisms between cultural resilience and mental health, there is a need for both qualitative studies and longitudinal studies.

Development of the Verona coding definitions of emotional sequences to code health providers' responses (VR-CoDES-P) to patient cues and concerns

OBJECTIVE

To present a method to classify health provider responses to patient cues and concerns according to the VR-CoDES-CC (Del Piccolo et al. (2009) [2] and Zimmermann et al. (submitted for publication) [3]). The system permits sequence analysis and a detailed description of how providers handle patient's expressions of emotion.

METHODS

The Verona-CoDES-P system has been developed based on consensus views within the "Verona Network of Sequence Analysis". The different phases of the creation process are described in detail. A reliability study has been conducted on 20 interviews from a convenience sample of 104 psychiatric consultations.

RESULTS

The VR-CoDES-P has two main classes of provider responses, corresponding to the degree of explicitness (yes/no) and space (yes/no) that is given by the health provider to each cue/concern expressed by the patient. The system can be further subdivided into 17 individual categories. Statistical analyses showed that the VR-CoDES-P is reliable (agreement 92.86%, Cohen's kappa 0.90 (±0.04) p<0.0001).

CONCLUSION

Once validity and reliability are tested in different settings, the system should be applied to investigate the relationship between provider responses to patients' expression of emotions and outcome variables.

PRACTICE IMPLICATIONS

Research employing the VR-CoDES-P should be applied to develop research-based approaches to maximize appropriate responses to patients' indirect and overt expressions of emotional needs.

Self-reported internalization symptoms and family factors in indigenous Sami and non-Sami adolescents in North Norway

Through differences in family socialization between indigenous and non-indigenous youth, there may be cultural differences in the impact of family factors on mental health outcome. Using structural equation modelling, this population-based study explored the relationship between symptoms of anxiety and depression and family factors in indigenous Sami and non-Sami boys and girls in North Norway. The findings show that family income was to a lesser degree related to internalization symptoms for Sami youth than non-Sami youth. For all groups except for Sami girls, family conflict and moving was associated with increasing symptoms. Sami boys differed from the other three groups with regard to the relationship between family connectedness and symptom level. These interaction effects were discussed in light of traditional Sami values and gender socialization. The present study has indicated that in the family socialization context, culture may be related to internalization symptoms in youth.

The effects of individual factors and school environment on mental health and prejudiced attitudes among Norwegian adolescents

INTRODUCTION

The aim was to examine the prevalence of mental health difficulties and prejudices toward mental illness among adolescents, and to analyze possible school and school class effects on these issues.

METHODS

The sample comprised 4,046 pupils (16-19 years) in 257 school classes from 45 Norwegian upper secondary schools. The estimated response rate among the pupils was about 96%. Self-reported mental health difficulties were measured with a four-item scale that covered emotional and behavioral difficulties. Prejudiced attitudes toward mental illness were assessed using a nine-item scale. Multilevel regression analysis was used to estimate the contribution of factors at the individual level, and at the school and class levels.

RESULTS

Most of the variance in self-reported mental health difficulties and prejudices was accounted for by individual level factors (92-94%). However, there were statistically significant school and class level effects (P < 0.01), confounded by socioeconomic factors. Mental health difficulties were commonly reported, more often by females than males (P < 0.01). Difficulties with emotions and attention were the two main problem areas, with definite to severe difficulties being reported by 19 and 21% of the females, and by 9 and 16% of the males, respectively. Prejudices were reported more often by males than females (P < 0.01). Both self-reported mental health difficulties and prejudiced attitudes were related to educational program, living situation, and parental education (P < 0.01).

CONCLUSION

The relatively high prevalences of mental health difficulties and prejudiced attitudes toward mental illness among adolescents indicate a need for effective mental health intervention programs. Targeted intervention strategies should be considered when there is evidence of a high number of risk factors in schools and school classes. Furthermore, the gender differences found in self-reported mental health difficulties and prejudices suggest a need for gender-differentiated programs.

Diagnosing psychotic disorders: validity, reliability and applications of the Diagnostic Interview for Psychosis (DIP). Italian version

AIMS

The Diagnostic Interview for Psychoses (DIP) is a comprehensive interview schedule for psychotic disorders, linked to the OPCRIT diagnostic algorithm, bridging the gap between fully structured, lay-administered schedules and semistructured, psychiatrist-administered interviews. Here we describe the validity, reliability and applications of the Italian version of the DIP.

METHODS

The interview was translated into Italian and its content validity tested by back translation. Sixty patients, drawn from among those who contacted the South-Verona Community Mental Health Service, were included in the study. Each patient was first assessed independently by two raters, one of whom conducted the interview, while the other assumed the role of observer. Subsequently (median: 89 days), 44 of these patients were re-interviewed by a third rater, who made an independent assessment. Diagnostic validity was assessed in 18 cases, interviewed with the DIP and using the SCAN as 'gold standard'.

RESULTS

The mean duration of the interview was 37 minutes for the inter-rater interviews and 39 minutes for the retest interviews. Good to excellent inter-rater reliability was demonstrated for both ICD-10 and DSM-IV diagnoses, while in the test-retest reliability pairwise agreement was high for half of the items. Diagnostic validity was good, with twelve out of the 18 DIP-OPCRIT diagnoses (67%) matching the SCAN diagnosis.

CONCLUSIONS

Overall, the results support the reliability and validity of the Italian translation of the DIP. The Italian version will be useful both in routine practice to establish standard reference diagnoses of psychosis and in the research field, where it can be used by academic researchers in clinical trials and epidemiological studies.

Unipolar depressive disorders have a common genotype

BACKGROUND

The purpose of this study was to estimate the contribution of genetic, common- and unique environmental factors in the aetiology of unipolar major depression (MD), and to investigate whether the unipolar depressive disorders; MD, atypical depression/depression NOS, dysthymia and depressive adjustment disorder can be viewed as various expressions of an underlying genetic commonality.

METHODS

A sample consisting of same-sexed mono- and dizygotic twins was drawn from in- and outpatient hospital registers (N=303). DSM-III-R criteria were assessed by personal interviews. One hundred and forty-three of the probands fulfilled the criteria for one or another unipolar depressive disorder. Cross-tabulations were used to compare concordance rates for MD and different combinations of MD and other unipolar depressive disorders. Correlations in liability and estimations of the heritability (h(2)) with biometrical model fitting were performed.

RESULTS

Concordance rates were higher among MZ- than among DZ pairs for both MD and all the different combinations of MD and other unipolar depressive disorders. Cross-concordance between MD and other unipolar disorders was observed. In all instances, except for the situation when MD was considered alone, the correlations in liability among MZ pairs were more than twice the correlations in liability among DZ pairs. The heritability of MD was 0.42, of MD+atypical depression 0.51, of MD+atypical depression+dysthymia 0.45 and of MD+atypical depression+dysthymia+depressive adjustment disorder 0.46.

LIMITATION

Probands were not sampled from the general population. Most often the same person interviewed both twins in a pair.

CONCLUSION

Unipolar MD is moderately heritable without significant shared family environmental effects. Unipolar depressive disorders taken together are moderately heritable without any detectable shared family environmental effects. The tendency is towards higher heritability estimates for the combined groups compared to MD alone. The study suggests that the disorders in the unipolar depressive spectrum may be different manifestations of the same genetic liability.

Heritability of bipolar spectrum disorders. Unity or heterogeneity?

BACKGROUND

The purpose of this study was to investigate whether the three disorders in the bipolar spectrum, Bipolar I disorder, Bipolar II disorder and Cyclothymia, are various expressions of an underlying genetic commonality.

METHOD

A sample consisting of same-sexed mono (MZ)- and dizygotic (DZ) twins were identified using hospital and outpatient registers (N=303). DSM-III-R criteria were assessed by personal interviews. Cross tabulations were used to compare concordance rates for different definitions of the bipolar spectrum. Correlations in liability and estimation of the heritability (h) with biometrical model fitting were performed.

RESULTS

Concordance rates were higher among MZ- than DZ pairs for all the single diagnoses and main combinations of diagnoses. Cross-concordance between different diagnoses was observed. The heritability of Bipolar I was .73, of Bipolar I+II .77 and of Bipolar I+II+Cyclothymia .71.

LIMITATION

Probands were not sampled from the general population. Most often the same person interviewed both twins in a pair. The statistical power was restricted in some sub-analyses.

CONCLUSION

The 'Bipolar Spectrum' category consisting of Bipolar I disorder, Bipolar II disorder and Cyclothymia constitute one entity with high heritability without detectable shared family environmental effects. Future genetic and clinical work might consider that all variants of the bipolar spectrum are an expression of one underlying genetic liability.

Genetic and environmental causes of the interrelationships between self-reported fears. A study of a non-clinical sample of Norwegian identical twins and their families

The present study reports results from a study of the self-reported fears of identical twins and their spouses and offspring. Factor analysis with oblique rotation of questionnaire responses yielded four correlated fear dimensions: situational fears, illness-injury fears, social fears, and fear of small animals. Models allowing for genetic and cultural transmission, together with specially correlated environments for twins, were fitted, both for separate fears and across fears. Simple models with only genetic and uncorrelated environments were sufficient to account for each the fear dimensions considered separately. The cross-dimensional analyses revealed a genetic and an environmental factor common to the four fear dimensions, together with fear-specific genetic and environmental factors. The impact of the common genetic and common environmental factor varied across dimensions. No evidence of cultural transmission or specially correlated twin environments of the cross-dimensional environments was detected. It is concluded that both common and fear-specific genes and (individual-specific) common and fear-specific environments are necessary to account for the data. The results are discussed in terms of the prepared learning hypothesis and the expectancy bias hypothesis.

Schizotypal personality disorder inside and outside the schizophrenic spectrum

The concept of schizotypal personality disorder has been heavily discussed since its introduction into the official classification of mental disorders in DSM-III. The aim of this study was to investigate the difference between schizotypal personality disorder within and outside the genetic spectrum of schizophrenia. Schizotypals with and without schizophrenic cotwins and first-degree relatives were compared, with individuals with other mental disorders and no mental disorders as controls. It appeared that only inadequate rapport and odd communication were more pronounced among schizotypals within, compared to schizotypals outside the schizophrenic spectrum. Schizotypals outside the schizophrenic spectrum, however, scored higher than schizotypals inside the schizophrenic spectrum on ideas of reference, suspiciousness, paranoia, social anxiety, self-damaging acts, chronic anger, free-floating anxiety and sensitivity to rejection. Interestingly, the four last features are seldom observed among schizotypals inside the schizophrenic spectrum. Monozygotic non-schizophrenic cotwins of schizophrenics score high on inadequate rapport, odd communication, social isolation and delusions/hallucinations. Monozygotic non-schizophrenic cotwins of schizotypals outside the schizophrenic genetic spectrum score high on illusions, depersonalization, derealization and magical thinking. Negative schizotypal features appear to be inside the schizophrenic spectrum, while positive borderline-like features are outside having another genetic endowment.

A twin study of personality disorders

No twin study has previously investigated the whole range of personality disorders (PDs) recorded by interviews. Based on twin and patient registries, 92 monozygotic (MZ) and 129 dizygotic (DZ) twin pairs were interviewed with the Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II). Observed prevalence rates from a normal population study of more than 2,000 individuals were used in combination with data from the present study to generate statistics assumed to be valid for a normal twin population, and these statistics were used for structural equation modeling. The best-fitting models had a heritability of .60 for PDs generally, .37 for the eccentric (A) cluster, .60 for the emotional (B) cluster, and .62 for the fearful (C) cluster. Among the specific PDs, the heritability appeared to be .79 for narcissistic, .78 for obsessive-compulsive, .69 for borderline, .67 for histrionic, .61 for schizotypal, .57 for dependent, .54 for self-defeating, .29 for schizoid, .28 for paranoid, and .28 for avoidant PDs. The best-fitting models never included shared-in-families environmental effects. However, a model with only shared familial and unique environmental effects could not be ruled out for dependent PD. Shared familial environmental effects may also influence the development of any PD and borderline PD. Passive-aggressive PD did not seem to be affected by genes or family environment at all. The low occurrence of antisocial PD in the twin sample precluded any model for this disorder. PDs seem to be more strongly influenced by genetic effects than almost any axis I disorder, and more than most broad personality dimensions. However, we observed a large variation in heritability among the different PDs, probably partly because of a moderate sample size and low prevalence of the specific disorders.

The heritability of common phobic fear: a twin study of a clinical sample

The aim of this study was to investigate the genetic and environmental contribution to common phobic fears, and to relate the findings to contemporary theories about the etiology of common phobic fears. Self-reported common phobic fear was studied in a treatment sample of 23 monozygotic and 38 same-sex dizygotic twin pairs. Heritability of .47 was observed for common phobic fear of small animals and social fear, and a heritability of .30 in common agoraphobic fear. For common fear of nature phenomena and situational fear, the heritability was 0. The finding that common nature and situational fears were solely caused by environmental factors is in support of learning theory, whereas results for animal, social, and other common phobic fear are in support of an integrative theory of biological preparedness, learning history, and a cognitive style of fearful expectation.

Family interaction: parental representation in schizophrenic patients

12 monozygotic (MZ) and 19 same-sexed dizygotic (DZ) twin pairs discordant for DSM-III-R schizophrenia completed the Parental Bonding Instrument (PBI). The schizophrenic twins described their parents as less caring and being more overprotective compared to their non-schizophrenic co-twins. These results were independent of age, sex and zygosity. Difference in paternal overprotection was the most important variable discriminating between the schizophrenic probands and their co-twins. Three different hypotheses regarding these findings are discussed.

A family study of anxiety disorders: familial transmission and relationship to mood disorder and psychoactive substance use disorder

The prevalence of mental disorders in 76 first-degree relatives (parents and nontwin siblings) of 33 subjects with anxiety disorder was compared with the prevalence of mental disorders in 45 first-degree relatives of 20 subjects with mood disorder and 13 first-degree relatives of 6 subjects with psychoactive substance use disorder. All subjects were personally interviewed with the Structured Clinical Interview for DSM-III-R Axis I (SCID I). Interrater reliability was high for most diagnoses. Significantly more first-degree relatives of subjects with anxiety disorder had panic disorder and generalized anxiety disorder compared with relatives of probands with mood disorder. Significantly more female than male relatives of anxiety subjects suffered from anxiety disorders; there were no gender differences in the prevalence of anxiety disorders in relatives of mood and psychoactive substance use disorder (PSUD) subjects. The combination of anxiety and mood disorder was overrepresented in first-degree relatives of subjects with the same type of comorbidity. In relatives of subjects with mixed anxiety and psychoactive substance use disorder, but no mood disorder, there was an overrepresentation of PSUD; mainly alcohol abuse or dependence.

"True" schizotypal personality disorder: a study of co-twins and relatives of schizophrenic probands

OBJECTIVE

The aim of the study was to investigate the type and nature of personality disorders among biological relatives of schizophrenic probands.

METHOD

A total of 176 nonschizophrenic co-twins and other first-degree relatives of schizophrenic probands were compared to 101 co-twins and first-degree relatives of probands with major depression.

RESULTS

Schizotypal personality disorders were more common and histrionic personality disorders less common among the biological relatives of schizophrenic probands than among relatives of probands with major depression. A further exploration of the schizotypal criteria revealed that the so-called "negative" criteria such as odd speech, inappropriate affect, and odd behavior, as well as excessive social anxiety, were significantly more common among the relatives of schizophrenic probands. The latter criterion seems particularly important. The so-called "positive" schizotypal criteria were partly, although not statistically significantly, more common among the relatives of probands with major depression. There were only minor differences in frequencies of the negative criteria between monozygotic co-twins, dizygotic co-twins, and other first-degree relatives of schizophrenic probands.

CONCLUSIONS

The present study suggests that DSM-III-R schizotypal disorder is defined by a set of criteria that partly describe a "true" schizophrenia-related personality disorder and partly features that are not specific for relatives of schizophrenic probands. Furthermore, the genetic relationship between schizophrenia and "true" schizotypal personality disorder seems weak. Excessive social anxiety may be a marker of a possible genetic link between the disorders.

A twin study of DSM-III-R anxiety disorders

The prevalence of anxiety disorders was studied in a sample of 20 monozygotic (MZ) and 29 dizygotic (DZ) co-twins of anxiety disorder probands. A comparison group of co-twins of 12 MZ and 20 DZ twin probands with other non-psychotic mental disorders was also studied. All subjects were personally interviewed with the Structured Clinical Interview for DSM-III-R Axis I (SCID-I). Panic disorder was significantly more prevalent in co-twins of panic probands. Generalized anxiety disorder (GAD) was more prevalent in co-twins of GAD probands with a history of mood disorder (NS). Post-traumatic stress disorder was significantly more prevalent in co-twins of anxiety probands and was more prevalent in MZ than in DZ co-twins. The prevalences of social and simple phobia were equal in co-twins of anxiety and comparison probands. For both panic disorder and generalized anxiety disorder the MZ:DZ concordance ratio was more than 2:1. The results support the hypothesis of a genetic contribution in the etiology of panic disorder, generalized anxiety disorder and post-traumatic stress disorder. The hypothesis that simple and social phobia are mainly caused by environmental experiences was also supported.

Parental representation in twins discordant for schizophrenia

Parental representation was assessed with the Parental Bonding Instrument (PBI) in 12 monozygotic (MZ) and 19 dizygotic (DZ) same-sexed twin pairs discordant for DSM-III-R schizophrenia. The schizophrenic twins reported less care and more overprotection from both parents than the non-schizophrenic co-twins. Multiple regression analysis disclosed that the results were independent of sex and age. Furthermore, the analysis demonstrated that whether the twins were monozygotic or dizygotic had no impact on the results. A stepwise discriminant analysis showed that difference in perceived paternal protection was the most important variable distinguishing between schizophrenic probands and their non-schizophrenic co-twins.

Birthweight and obstetric complications in schizophrenic twins

Birthweight and obstetric complications were registered retrospectively in 24 monozygotic (MZ) twin pairs. Sixteen pairs were discordant and 8 pairs were concordant for DSM-III-R schizophrenia. There was no significant intrapair difference in birthweight between the 2 groups of MZ twins. Prematurity was more often observed in the discordant pairs, but neither differences in prematurity nor differences in obstetric complications between the concordant and discordant twins reached significance. No difference in respect of family history of schizophrenia between the 2 groups of MZ twins was found. In the discordant pairs, no significant difference between the schizophrenic twin and the nonschizophrenic co-twin was observed regarding birth order, birthweight or physical condition at birth.

Subtypes of schizophrenia--evidence from a twin-family study

In a combined twin-family study, the concordance for subtype of schizophrenia was investigated. The sample included 31 monozygotic (MZ) and 28 dizygotic (DZ) twin probands fulfilling the criteria of DSM-III-R schizophrenia. Their co-twins and first-degree relatives were personally interviewed and diagnosed in accordance with DSM-III-R. Any twin or relative diagnosed as schizophrenic was subclassified as either paranoid or nonparanoid. Schizophrenia was more often observed in co-twins of MZ probands with nonparanoid schizophrenia than in MZ probands with paranoid schizophrenia, indicating a stronger genetic influence in nonparanoid schizophrenia. Fifteen MZ pairs were concordant for schizophrenia, and 13 of these pairs were also concordant for subtype. Such a relationship was not observed in the first-degree relatives with schizophrenia. Our results indicate a complex etiology of subtypes in schizophrenia, and to some extent the etiology of subtypes may differ from the etiology of schizophrenia.

High interrater reliability for the Structured Clinical Interview for DSM-III-R Axis I (SCID-I)

The interrater reliability of the Structured Clinical Interview for DSM-III-R (SCID) was studied. Fifty-four audiotaped SCID interviews were rated independently by 3 raters. The highest interrater agreements were observed for schizophrenia (0.94), major depressive disorder (0.93), dysthymia (0.88), generalized anxiety disorder (0.95), panic disorder (0.88), alcohol use disorder (0.96) and other psychoactive substance use disorder (0.85). The remaining diagnoses of mood and anxiety disorders obtained acceptable interrater agreement (0.70-0.80), with an exception for obsessive-compulsive disorder (0.40). The poorest agreement was obtained for somatoform disorders ( -0.03). Lack of hierarchy in DSM-III-R allows for multiple Axis I diagnoses. Interrater reliability for multiple diagnoses was tested. Agreement was generally good for combinations of 2 diagnoses, and poorer when 3 diagnoses were combined. Our findings confirm that SCID yields highly reliable diagnoses. SCID is recommended for research on mental disorders.

Mental disorders in first-degree relatives of schizophrenics

A total 215 first-degree relatives of 88 twin probands with schizophrenia, mood disorders and nonaffective psychoses were studied. The twins' parents and siblings were personally interviewed with structured diagnostic instruments and diagnosed in accordance with DSM-III-R criteria. The first-degree relatives were interviewed by interviewers who were blind to the twins' diagnoses. Schizophrenia and schizotypal personality disorder were significantly more frequent in first-degree relatives of schizophrenic twins. Respectively, anxiety and mood disorders were significantly more prevalent among the parents and siblings of probands with mood disorders. Schizophrenic spectrum disorders were significantly more common in the families of schizophrenic probands compared with relatives of mood disorder probands, thus confirming a relationship between schizophrenia and schizophrenic spectrum disorders. However, we cannot, based on our study, specify whether this relationship is caused by genetic or environmental factors.

Twin concordance for DSM-III-R schizophrenia

The monozygotic (MZ)/dizygotic (DZ) concordance rates for schizophrenia and the relationship between schizophrenia and schizophrenic spectrum disorders were studied in a sample of 31 MZ and 28 DZ schizophrenic probands and their co-twins. All subjects were personally interviewed with structured diagnostic instruments and classified according to DSM-III-R criteria. The concordance rates of 48% for MZ twins and 4% for DZ twins indicate a genetic transmission of DSM-III-R schizophrenia. In addition to the schizophrenic co-twins, 3 MZ co-twins had a noneffective psychotic disorder, thus supporting the hypothesis that genes are involved in the development of Axis I schizophrenic spectrum disorders. Schizotypal and paranoid personality disorders were observed in both MZ and DZ co-twins. These disorders may be familially related to schizophrenia, but a genetic relationship was not confirmed for the Axis II spectrum disorders. A substantial number of MZ co-twins of schizophrenic probands had no mental disorder.