How changes in depression severity and borderline personality disorder intensity are linked - a cohort study of depressed patients with and without borderline personality disorder

BACKGROUND

Borderline personality disorder (BPD) is often complicated by comorbid major depressive episodes (MDEs), which can occur as part of major depressive disorder (MDD) or bipolar disorder (BD). Such comorbidity is related to worse outcomes in both disorders. Subsyndromal features of BPD are also common in depression. However, studies of simultaneous changes in BPD and depression severities are scarce, and their interactions are poorly understood.

AIMS

Studying the associations between changes in BPD and depression symptoms over the course of an MDE.

METHODS

In a 6-month naturalistic cohort study of MDE/BPD, MDE/MDD, and MDE/BD patients (N = 95), we measured change in BPD features between baseline and six months with the Borderline Personality Disorder Severity Index (BPDSI), an interviewer-rated instrument quantifying recent temporal frequency of BPD symptoms. We examined changes in BPD severity and their correlation with depression severity and other clinical measures and compared these across patient groups.

RESULTS

There were significant reductions in BPD severity, both in number of positive BPD criteria (-0.35, sd 1.38, p = 0.01672) and in BPDSI scores (-4.23, SD 6.74, p < 0.001), reflecting mainly a reduction in temporal frequency of symptoms. These were similar in all diagnostic groups. In multivariate regression models, changes in depression severity independently associated with changes in symptoms in the BDSI. This relationship was strongest in MDE/BPD patients but was not found in MDD patients without BPD.

CONCLUSIONS

In the six-month follow-up, BPD features in MDE patients alleviated mainly by decreasing temporal symptom frequency and intensity. In BPD patients with comorbid MDE, changes in both conditions are strongly correlated.

Affect dimensions and variability during major depressive episodes: Ecological momentary assessment of unipolar, bipolar, and borderline patients and healthy controls

Differentiating major depressive episodes (MDEs) of major depressive disorder (MDD), bipolar disorder (MDE/BD) and the MDEs comorbid with borderline personality disorder (MDE/BPD) is crucial for appropriate treatment, and knowledge of phenomenological differences may aid this. However, studies comparing affect experiences of these three patient groups and healthy subjects are scarce. In our study, participants (N = 114), including patients with MDD (n = 34), MDE/BD (n = 27), and MDE/BPD (n = 24), and healthy controls (HC, n = 29) responded to ecological momentary assessment (EMA) with ten circumplex model affect items ten times daily for seven days (7709 recordings). Explorative factor analysis resulted in two affect dimensions. The positive dimension included active, excited, cheerful (high arousal), and content (low arousal) affects, and the negative dimension irritated, angry, and nervous (high arousal) affects. Relative to HC, patients reported 3.5-fold negative affects (mean MDD 1.36 (SD 0.92), MDE/BD 1.43 (0.76), MDE/BPD 1.81 (0.95) vs. HC 0.44 (0.49) (p < 0.01)) but 0.5-fold positive affects (2.01 (0.90), 1.95 (0.89), 2.24 (1.03), vs. 3.2 (0.95), respectively (p < 0.01)). We used multilevel modelling. Negative-affect within-individual stability was lowest in MDE/BPD and highest in MDD. Negative affect predicted concurrent positive affect more in MDE/BPD than in MDD. Moderate size of subcohorts and no inpatients were limitations. Despite apparently similar MDEs, affective experiences may differ between BPD, BD, and MDD patients. Clinical subgroups of patients with depression may vary in affective instability and concurrent presence of negative and positive affects during depression.

Borderline personality disorder and depression severity predict suicidal outcomes: A six-month prospective cohort study of depression, bipolar depression, and borderline personality disorder

BACKGROUND

Suicide risk is high in patients with major depressive disorder (MDD), bipolar disorder (BD) and borderline personality disorder (BPD). Whether risk levels of and risk factors for suicidal ideation (SI) and suicide attempts (SA) are similar or different in these disorders remains unclear, as few directly comparative studies exist. The relationship of short-term changes in depression severity and SI is underinvestigated, and might differ across groups, for example, between BPD and non-BPD patients.

METHODS

We followed, for 6 months, a cohort of treatment-seeking, major depressive episode (MDE) patients in psychiatric care (original n = 124), stratified into MDE/MDD, MDE/BD and MDE/BPD subcohorts. We examined risks of suicide-related outcomes and their risk factors prospectively. We examined the covariation of SI and depression over time with biweekly online modified Patient Health Questionnaire 9 surveys and analysed this relationship through multi-level modelling.

RESULTS

Risk of SA in BPD (22.2%) was higher than non-BPD (4.23%) patients. In regression models, BPD severity was correlated with risk of SA and clinically significant SI. During follow-up, mean depression severity and changes in depression symptoms were associated with SI risk regardless of diagnosis.

CONCLUSIONS

Concurrent BPD in depression seems predictive for high risk of SA. Severity of BPD features is relevant for assessing risk of SA and SI in MDE. Changes in depressive symptoms indicate concurrent changes in risk of SI. BPD status at intake can index risk for future SA, whereas depressive symptoms appear a useful continuously monitored risk index.

Relationship between daily rated depression symptom severity and the retrospective self-report on PHQ-9: A prospective ecological momentary assessment study on 80 psychiatric outpatients

BACKGROUND

Depression-related negative bias in emotional processing and memory may bias accuracy of recall of temporally distal symptoms. We tested the hypothesis that when responding to the Patient Health Questionnaire (PHQ-9) the responses reflect more accurately temporally proximal than distal mood states.

METHODS

Currently, depressed psychiatric outpatients (N = 80) with depression confirmed in semi-structured interviews had the Aware application installed on their smartphones for ecological momentary assessment (EMA). The severity of "low mood", "hopelessness", "low energy", "anhedonia", and "wish to die" was assessed on a Likert scale five times daily during a 12-day period, and thereafter, the PHQ-9 questionnaire was completed. We used auto- and cross-correlation analyses and linear mixed-effects multilevel models (LMM) to investigate the effect of time lag on the association between EMA of depression symptoms and the PHQ-9.

RESULTS

Autocorrelations of the EMA of depressive symptom severity at two subsequent days were strong (r varying from 0.7 to 0.9; p < 0.001). "Low mood" was the least and "wish to die" the most temporally stable symptom. The correlations between EMA of depressive symptoms and total scores of the PHQ-9 were temporally stable (r from 0.3 to 0.6; p < 0.001). No effect of assessment time on the association between EMA data and the PHQ-9 emerged in the LMM.

LIMITATIONS

Altogether 11.5 % of observations were missing.

CONCLUSIONS

Despite fluctuations in severity of some of the depressive symptoms, patients with depression accurately recollect their most dominant symptoms, without a significant recall bias favouring the most recent days, when responding to the PHQ-9.

Finnish Psychotherapy Quality Register: rationale, development, and baseline results

BACKGROUND

The push to systematically follow treatment outcomes in psychotherapies to improve health care is increasing worldwide. To manage psychotherapeutic services and facilitate tailoring of therapy according to feedback a comprehensive and feasible data system is needed.

AIMS

To describe the Finnish Psychotherapy Quality Register (FPQR), a comprehensive database on availability, quality, and outcomes of psychotherapies.

METHODS

We describe the development of the FPQR and outcome for outsourced psychotherapies for adults in Helsinki and Uusimaa hospital district (HUS). Symptom severity and functioning are measured with validated measures (e.g. CORE-OM, PHQ-9, OASIS, AUDIT, and SOFAS). Questionnaires on therapeutic alliance, risks, methods, and goals are gathered from patients and psychotherapist.

RESULTS

During 2018-2021, the FPQR included baseline data for 7274 unique patients and 336 psychotherapists. Response rate of measures was 85-98%. The use of the register was mandatory for the outsourced therapist of the hospital districts, and the patients were strongly recommended to fulfill the questionnaires. We report outcome for three groups of patients (n = 1844) with final/midterm data. The effect sizes for long psychotherapy (Hedge's g = 0.65 of SOFAS) were smaller than those for short psychotherapy (g = 0.75-0.91). Within three months of referral, 26-60% entered treatment depending on short- or long-term therapy.

CONCLUSION

The FPQR forms a novel rich database with commensurate data on availability and outcomes of outsourced psychotherapies. It may serve as a basis for a national comprehensive follow-up system of psychosocial treatments. The Finnish system seems to refer patients with milder symptoms to more intensive treatments and achieve poorer results compared to the IAPT model in UK, Norway, or Australia.

Bipolar disorder predicted shorter and borderline personality disorder symptoms longer time to remission - A prospective cohort study of major depressive patients

BACKGROUND

Major depressive episodes (MDEs) of major depressive (MDD) or bipolar disorders (BD) are frequently complicated by features of borderline personality disorder (BPD). Mixed features are a hallmark of BD and affective lability of BPD, and both may markedly influence illness course. However, direct comparisons of outcome of depression in MDD, BD, and BPD are scarce.

METHODS

In a cohort study based on stratified sampling, we diagnosed psychiatric MDE patients with SCID-I/P and SCID-II interviews and examined mixed symptoms using the Mix-MDE scale and borderline symptoms using the Borderline Personality Disorder Severity Index. During a six-month prospective follow-up, the MDE patients with MDD (n = 39), BD (n = 33), or BPD (n = 23) completed biweekly online assessments. Using life chart methodology, we divided the follow-up period into qualitatively different mood state periods. We investigated durations of mood episodes, times to first full symptomatic remission, and their predictors.

RESULTS

Remission rates were similar in MDD, MDE/BD, and MDE/BPD patients. MDE/BD patients experienced more numerous and shorter distinct mood state periods during follow-up than the others. MDE/BD was associated with shorter (HR = 2.44, 95 % CI = 1.27-4.67) and dimensionally assessed BPD severity with longer time to first remission (HR = 0.95, 95 % CI = 0.91-1.00).

LIMITATIONS

Moderate sample size and follow-up duration.

CONCLUSIONS

Course of illness over six months differs between the three depressive groups. Bipolar depressive patients have the most alternating course and the shortest time to first period of remission. Dimensionally assessed severity of BPD may predict longer time to remission from depression.

Bipolar disorder correlated to shorter remission latency and borderline personality disorder symptom severity to longer in depression – a prospective cohort study of major depressive patients

Introduction

Major depressive episodes (MDE) occur in major depressive (MDD) and bipolar disorders (BD), and are frequently complicated by borderline personality disorder (BPD). Mixed affective symptomatology is a hallmark of BD, and affective lability of BPD; both may markedly influence illness course. However, direct comparisons of outcome of depression in MDD, BD and BPD are scarce.

Objectives

To investigate course of illness and outcome of depression in MDD, bipolar and borderline patients.

Methods

In this six-month, prospective cohort study of secondary-level psychiatric MDE patients (n = 95), after initial assessment, the patients (N = 95) completed biweekly online assessments of mood symptoms. We divided the follow up period into qualitatively different mood state periods based on multiple prospective information sources. We examined mixed affective symptoms and borderline symptom severity dimensionally. Outcomes assessed included clinical course, time to first full symptomatic remission, and factors predicting these.

Results

Remission rates according to DSM-5 were similar in MDD, MDE/BD and MDE/BPD patients. Bipolar patients experienced more shorter qualitatively distinct mood state periods during follow-up than the others. Bipolar disorder was associated with shorter (HR = 2.44, 95% CI = 1.27–4.67, see fig. 1) and dimensionally assessed BPD severity with longer time to first remission (HR = 0.95 per point., CI = 0.91–1.00).

Conclusions

Course of illness differs between the three depressive groups in the medium term. Bipolar depressive patients have the most alternating course and the shortest time to first remission. Dimensionally assessed severity of BPD may be prognostic of longer depressive remission latency.

Disclosure

I am employed by a psychiatric treatment provider, treating e.g. patients suffering from depression, bipolar disorder and borderline personality disorder.

Reduced visual contrast suppression during major depressive episodes

BACKGROUND

Previous studies have suggested that processing of visual contrast information could be altered in major depressive disorder. To clarify the changes at different levels of the visual hierarchy, we behaviourally measured contrast perception in 2 centre-surround conditions, assessing retinal and cortical processing.

METHODS

As part of a prospective cohort study, our sample consisted of controls (n = 29; 21 female) and patients with unipolar depression, bipolar disorder and borderline personality disorder who had baseline major depressive episodes (n = 111; 74 female). In a brightness induction test that assessed retinal processing, participants compared the perceived luminance of uniform patches (presented on a computer screen) as the luminance of the backgrounds was varied. In a contrast suppression test that assessed cortical processing, participants compared the perceived contrast of gratings, which were presented with collinearly or orthogonally oriented backgrounds.

RESULTS

Brightness induction was similar for patients with major depressive episodes and controls (p = 0.60, d = 0.115, Bayes factor = 3.9), but contrast suppression was significantly lower for patients than for controls (p < 0.006, d = 0.663, Bayes factor = 35.2). We observed no statistically significant associations between contrast suppression and age, sex, or medication or diagnostic subgroup. At follow-up (n = 74), we observed some normalization of contrast perception.

LIMITATIONS

We assessed contrast perception using behavioural tests instead of electrophysiology.

CONCLUSION

The reduced contrast suppression we observed may have been caused by decreased retinal feedforward or cortical feedback signals. Because we observed intact brightness induction, our results suggest normal retinal but altered cortical processing of visual contrast during a major depressive episode. This alteration is likely to be present in multiple types of depression and to partially normalize upon remission.

Presence and Overlap of Bipolar Symptoms and Borderline Features during Major Depressive Episodes

BACKGROUND

Bipolar symptoms and borderline personality features occur in both unipolar and bipolar major depressive episodes (MDEs). We investigated their prevalence, severity, co-occurrence and overlap.

METHODS

We interviewed 124 psychiatric outpatients with MDE using the Structured Clinical Interview for DSM-IV-TR Axis I and II Disorders, the Borderline Personality Disorder Severity Index (BPDSI-IV), and about past (hypo)manic episodes, and stratified them according to the principal diagnosis into subcohorts of major depressive disorder (MDD, n = 50), bipolar disorder (BD, n = 43), and borderline personality disorder (BPD, n = 31). We quantified (hypo)manic symptoms using a novel semi-structured interview (MIXed symptoms during MDE, MIX-MDE) with good psychometric qualities.

RESULTS

The subcohorts did not differ in MDE severity. They differed significantly in some (hypo)manic symptoms being present on most days in 24% of MDD, 30% of BD, and 42% of BPD subcohort, but only 5% of the BD subcohort fulfilled the DSM-5 mixed features. The mean MIX-MDE scores were 5.7 (SD 4.0), 12.0 (8.2) and 10.5 (7.5), and BPDSI-IV scores 15.6 (7.0), 17.2 (6.2) and 26.9 (8.7), respectively (both p < 0.001). (Hypo)manic days and unspecific symptoms of distractibility and irritability inflated the correlation of observed (hypo)manic symptoms and borderline features.

LIMITATIONS

Moderate sample size, limited age variation (18-50 years); no previous validation of MIX-MDE.

CONCLUSIONS

Presence of some mixed and borderline features is common in MDEs, with overlap and diagnosis-specific differences. Unspecific symptoms of irritability and distractibility and the aggravating impact of hypomania on perceived BPD features blur the differential diagnosis.

Borderline Personality Disorder With Depression Confers Significant Risk of Suicidal Behavior in Mood Disorder Patients-A Comparative Study

OBJECTIVE

We investigated risk factors for suicidal ideation and behavior among currently depressed patients with major depressive disorder (MDD), major depressive episode (MDE) in bipolar disorder (BD), or MDE with comorbid borderline personality disorder (MDE/BPD). We compared current and lifetime prevalence of suicidal ideation and behavior, and investigated dimensional measures of BPD or mixed affective features of the MDE as indicators of risk.

METHODS

Based on screening of 1,655 referrals, we recruited 124 psychiatric secondary care outpatients with MDE and stratified them into three subcohorts (MDD, BD, and MDE/BPD) using the Structured Clinical Interview for DSM-IV I and II. We examined suicidal ideation and behavior with the Columbia Suicide Severity Rating Scale (CSSRS). In addition, we quantified the severity of BPD symptoms and BD mixed features both categorically/diagnostically and dimensionally (using instruments such as the Borderline Personality Disorder Severity Index) in two time frames.

RESULTS

There were highly significant differences between the lifetime prevalences of suicide attempts between the subcohorts, with attempts reported by 16% of the MDD, 30% of the BD, and 60% of the BPD subcohort. Remarkably, the lifetime prevalence of suicide attempts in patients with comorbid BD and BPD exceeded 90%. The severity of BPD features was independently associated with risk of suicide attempts both lifetime and during the current MDE. It also associated in a dose-dependent manner with recent severity of ideation in both BPD and non-BPD patients. In multinominal logistic regression models, hopelessness was the most consistent independent risk factor for severe suicidal ideation in both time frames, whereas younger age and more severe BPD features were most consistently associated with suicide attempts.

CONCLUSIONS

Among patients with major depressive episodes, diagnosis of bipolar disorder, or presence of comorbid borderline personality features both imply remarkably high risk of suicide attempts. Risk factors for suicidal ideation and suicidal acts overlap, but may not be identical. The estimated severity of borderline personality features seems to associate with history of suicidal behavior and current severity of suicidal ideation in dose-dependent fashion among all mood disorder patients. Therefore, reliable assessment of borderline features may advance the evaluation of suicide risk.

Short-term escitalopram treatment normalizes aberrant self-referential processing in major depressive disorder

BACKGROUND

Increased self-focus and negative self-concept play an important role in depression. Antidepressants influence self-referential processing in healthy volunteers, but their function in self-processing of depressed patients remains unknown.

METHODS

Thirty-two depressed patients were randomly allocated to receive either escitalopram 10 mg or placebo for one week. After one week, neural responses to positive and negative self-referential adjectives and neutral control stimuli were assessed with functional magnetic resonance imaging. A group of matched healthy volunteers served as a control group.

RESULTS

Escitalopram decreased responses of medial fronto-parietal regions to self-referential words relative to non-emotional control stimuli, driven by increased responses to the control condition. Escitalopram also increased responses in the pre-defined region of the medial prefrontal cortex (MPFC) and the anterior cingulate cortex (ACC) to positive relative to negative words. Importantly, the changes in neural responses occurred before any effect on depressive symptoms, implying a direct effect of escitalopram. Furthermore, the placebo group had decreased responses of the MPFC and the ACC to positive self-referential processing relative to the matched healthy controls. However, neural responses of the escitalopram group and the healthy unmedicated controls were similar.

LIMITATIONS

Differences between the groups in self-reported depression symptoms and personality traits may have influenced the results.

CONCLUSION

One-week treatment with escitalopram normalized aberrant self-referential processing in depressed patients, shifting the focus from the self to the external environment and potentiating positive self-referential processing. This may be an important factor in mechanism of action of antidepressants.

Genome-Wide Association Study of Psychosis Proneness in the Finnish Population

The current study examined quantitative measures of psychosis proneness in a nonpsychotic population, in order to elucidate their underlying genetic architecture and to observe if there is any commonality to that already detected in the studies of individuals with overt psychotic conditions, such as schizophrenia and bipolar disorder. Heritability, univariate and multivariate genome-wide association (GWAs) tests, including a series of comprehensive gene-based association analyses, were developed in 4269 nonpsychotic persons participating in the Northern Finland Birth Cohort 1966 study with information on the following psychometric measures: Hypomanic Personality, Perceptual Aberration, Physical and Social Anhedonia (also known as Chapman's Schizotypia scales), and Schizoidia scale. Genome-wide genetic data was available for ~9.84 million SNPs. Heritability estimates ranged from 16% to 27%. Phenotypic, genetic and environmental correlations ranged from 0.04-0.43, 0.25-0.73, and 0.12-0.43, respectively. Univariate GWAs tests revealed an intronic SNP (rs12449097) at the TMC7 gene (16p12.3) that significantly associated (P = 3.485 × 10-8) with the hypomanic scale. Bivariate GWAs tests including the hypomanic and physical anhedonia scales suggested a further borderline significant SNP (rs188320715; P-value = 5.261 × 10-8, ~572 kb downstream the ARID1B gene at 6q25.3). Gene-based tests highlighted 20 additional genes of which 5 had previously been associated to schizophrenia and/or bipolar disorder: CSMD1, CCDC141, SLC1A2, CACNA1C, and SNAP25. Altogether the findings explained from 3.7% to 14.1% of the corresponding trait heritability. In conclusion, this study provides preliminary genomic evidence suggesting that qualitatively similar biological factors may underlie different psychosis proneness measures, some of which could further predispose to schizophrenia and bipolar disorder.

Single dose of mirtazapine modulates whole-brain functional connectivity during emotional narrative processing

The link between neurotransmitter-level effects of antidepressants and their clinical effect remain poorly understood. A single dose of mirtazapine decreases limbic responses to fearful faces in healthy subjects, but it is unknown whether this effect applies to complex emotional situations and dynamic connectivity between brain regions. Thirty healthy volunteers listened to spoken emotional narratives during functional magnetic resonance imaging (fMRI). In an open-label design, 15 subjects received 15mg of mirtazapine two hours prior to fMRI while 15 subjects served as a control group. We assessed the effects of mirtazapine on regional neural responses and dynamic functional connectivity associated with valence and arousal. Mirtazapine attenuated responses to unpleasant events in the right fronto-insular cortex, while modulating responses to arousing events in the core limbic regions and the cortical midline structures (CMS). Mirtazapine decreased responses to unpleasant and arousing events in sensorimotor areas and the anterior CMS implicated in self-referential processing and formation of subjective feelings. Mirtazapine increased functional connectivity associated with positive valence in the CMS and limbic regions. Mirtazapine triggers large-scale changes in regional responses and functional connectivity during naturalistic, emotional stimuli. These span limbic, sensorimotor, and midline brain structures, and may be relevant to the clinical effectiveness of mirtazapine.

Physical activity before radical prostatectomy reduces sick leave after surgery - results from a prospective, non-randomized controlled clinical trial (LAPPRO)

BACKGROUND

Studies have reported that early physical rehabilitation after surgical procedures is associated with improved outcome measured as shorter hospital stay and enhanced recovery. The aim of this study was to explore the relationship between the preoperative physical activity level and subsequent postoperative complications, sick-leave and hospital stay after radical prostatectomy for prostate cancer in the setting of the LAPPRO trial (LAParoscopic Prostatectomy Robot Open).

METHODS

LAPPRO is a prospective controlled trial, comparing robot-assisted laparoscopic and open surgery for localized prostate cancer between 2008 and 2011. 1569 patients aged 64 or less with an occupation were included in this sub-study. The Gleason score was <7 in 52 % of the patients. Demographics and the level of self-assessed preoperative physical activity, length of hospital stay, complications, quality of life, recovery and sick-leave were extracted from clinical record forms and questionnaires. Multivariable logistic regression, with log-link and logit-link functions, was used to adjust for potential confounding variables.

RESULTS

The patients were divided into four groups based on their level of activity. As the group with lowest engagement of physical activity was found to be significantly different in base line characteristics from the other groups they were excluded from further analysis. Among patients that were physically active preoperativelly (n = 1467) there was no significant difference between the physical activity-groups regarding hospital stay, recovery or complications. However, in the group with the highest self-assessed level of physical activity, 5-7 times per week, 13 % required no sick leave, compared to 6.3 % in the group with a physical activity level of 1-2 times per week only (p < 0.0001).

CONCLUSIONS

In our study of med operated with radical prostatectomy, a high level of physical activity preoperatively was associated with reduced need for sick leave after radical prostatectomy compared to men with lower physical activity.

TRIAL REGISTRATION

The trial is registered at the ISCRTN register. ISRCTN06393679 .

A single dose of mirtazapine attenuates neural responses to self-referential processing

Increased self-focus is a core factor in the psychopathology of depression. Cortical midline structures (CMS) are implicated in the neurobiology of self, depression and antidepressant treatment response. Mirtazapine, an antidepressant that increases serotonin and norepinephrine release, enhances processing of positive and attenuates processing of negative emotional information in healthy volunteers after a single dose. These early changes, which are opposite to the negative information bias in depression, may be important for the therapeutic effect of mirtazapine. It nevertheless remains unresolved whether/how mirtazapine specifically influences processing of self-referential emotional information.Half of the healthy volunteers (n=15/30) received a single dose of mirtazapine, in an open-label design, two hours before functional magnetic resonance imaging (fMRI), and the other half was scanned as a control group without medication. During fMRI the participants categorized positive and negative self-referential adjectives.Mirtazapine attenuated responses to self-referential processing in the medial prefrontal cortex and the anterior cingulate cortex. Mirtazapine further decreased responses to positive self-referential processing in the posterior cingulate cortex and parietal cortex.These decreased responses of the CMS suggest that mirtazapine may rapidly improve the ability of the CMS to down-regulate self-referential processing. In depressed patients, this could lead to decreased self-focus and rumination, contributing to the antidepressant effect.

The effect of personality on daily life emotional processes

Personality features are associated with individual differences in daily emotional life, such as negative and positive affectivity, affect variability and affect reactivity. The existing literature is somewhat mixed and inconclusive about the nature of these associations. The aim of this study was to shed light on what personality features represent in daily life by investigating the effect of the Five Factor traits on different daily emotional processes using an ecologically valid method. The Experience Sampling Method was used to collect repeated reports of daily affect and experiences from 104 healthy university students during one week of their normal lives. Personality traits of the Five Factor model were assessed using NEO Five Factor Inventory. Hierarchical linear modeling was used to analyze the effect of the personality traits on daily emotional processes. Neuroticism predicted higher negative and lower positive affect, higher affect variability, more negative subjective evaluations of daily incidents, and higher reactivity to stressors. Conscientiousness, by contrast, predicted lower average level, variability, and reactivity of negative affect. Agreeableness was associated with higher positive and lower negative affect, lower variability of sadness, and more positive subjective evaluations of daily incidents. Extraversion predicted higher positive affect and more positive subjective evaluations of daily activities. Openness had no effect on average level of affect, but predicted higher reactivity to daily stressors. The results show that the personality features independently predict different aspects of daily emotional processes. Neuroticism was associated with all of the processes. Identifying these processes can help us to better understand individual differences in daily emotional life.

Neuropeptide precursor VGF is genetically associated with social anhedonia and underrepresented in the brain of major mental illness: its downregulation by DISC1

In a large Scottish pedigree, disruption of the gene coding for DISC1 clearly segregates with major depression, schizophrenia and related mental conditions. Thus, study of DISC1 may provide a clue to understand the biology of major mental illness. A neuropeptide precursor VGF has potent antidepressant effects and has been reportedly associated with bipolar disorder. Here we show that DISC1 knockdown leads to a reduction of VGF, in neurons. VGF is also downregulated in the cortices from sporadic cases with major mental disease. A positive correlation of VGF single-nucleotide polymorphisms (SNPs) with social anhedonia was also observed. We now propose that VGF participates in a common pathophysiology of major mental disease.

Budesonide/formoterol maintenance and reliever therapy in Asian patients (aged ≥16 years) with asthma: a sub-analysis of the COSMOS study

BACKGROUND

The combination of an inhaled corticosteroid (ICS), budesonide, and a rapid long-acting β(2)-agonist (LABA), formoterol, in a single inhaler for use as maintenance and reliever therapy (Symbicort Turbuhaler SMART™) effectively achieves a high level of asthma control and reduces exacerbations and asthma-related hospitalizations. The COSMOS study, a multinational, 12-month study (N = 2143), compared budesonide/formoterol maintenance and reliever therapy with salmeterol/fluticasone propionate plus as-needed salbutamol, allowing physicians to modify maintenance doses of both combinations according to routine clinical practice.

OBJECTIVE

The aim of this post hoc sub-group analysis of the COSMOS study is to provide focused data on budesonide/formoterol maintenance and reliever therapy compared with salmeterol/fluticasone propionate plus as-needed salbutamol in patients (aged ≥16 years) enrolled across Asian countries, specifically China, Korea, Taiwan and Thailand.

METHODS

This sub-analysis of the COSMOS study concerns all 404 randomized patients ≥16 years of age (mean forced expiratory volume in 1 second [FEV(1)] 69.1%) who were recruited from Asian countries. Patients received either budesonide/formoterol (Symbicort Turbuhaler SMART™, n = 198), starting dose 160 mg/4.5 mg two inhalations twice daily (bid) [plus additional as-needed inhalations], or salmeterol/fluticasone propionate (Seretide(®) Diskus(®), n = 206), starting dose 50 mg/250 mg bid (plus salbutamol [Ventolin(®)] as needed). Maintenance doses could be titrated by clinicians after the first 4 weeks (budesonide/formoterol maintenance plus as needed, n = 198; salmeterol/fluticasone propionate plus salbutamol, n = 206). To allow for free adjustment in maintenance doses in both arms, the trial was performed open-label; maintenance doses could be titrated by clinicians after the first 4 weeks. The time to first severe exacerbation (defined as deterioration in asthma resulting in hospitalization/emergency room treatment, oral corticosteroids for ≥3 days or unscheduled visit leading to treatment change) was the primary variable.

RESULTS

The time to first severe exacerbation was prolonged in patients using maintenance plus as-needed budesonide/formoterol compared with salmeterol/fluticasone propionate plus salbutamol (log-rank p = 0.024). The risk of a first exacerbation was reduced by 44% (hazard ratio 0.56; 95% confidence interval [CI] 0.32, 0.95; p = 0.033) in patients using the adjusted budesonide/formoterol regimen versus titrated salmeterol/fluticasone propionate. The overall exacerbation rates were 0.16 versus 0.26 events/patient-year, respectively, with a 38% reduction (rate ratio 0.62/patient/year; 95% CI 0.41, 0.94; p = 0.024) in favour of the budesonide/formoterol regimen. Compared with baseline, both regimens provided clinically relevant improvements in asthma control, quality of life and FEV(1); no statistically significant differences between the treatment groups were observed. Mean adjusted (standard deviation) ICS dose (expressed as beclomethasone dose equivalents) during treatment, including as-needed budesonide doses, was 944 (281) and 1034 (394) μg/day, respectively, in patients using maintenance plus as-needed budesonide/formoterol compared with salmeterol/fluticasone propionate.

CONCLUSION

In patients (aged ≥16 years) enrolled from Asian countries as part of the COSMOS study, the budesonide/formoterol maintenance and reliever regimen was associated with a lower future risk of exacerbations versus the physicians' free choice of salmeterol/fluticasone propionate dose plus salbutamol. Single inhaler combination treatment with maintenance plus as-needed budesonide/formoterol was also at least as efficacious as salmeterol/fluticasone propionate dose plus salbutamol in improving current asthma control.

Temperament clusters in a normal population: implications for health and disease

Background

The object of this study was to identify temperament patterns in the Finnish population, and to determine the relationship between these profiles and life habits, socioeconomic status, and health.

Methods/Principal Findings

A cluster analysis of the Temperament and Character Inventory subscales was performed on 3,761 individuals from the Northern Finland Birth Cohort 1966 and replicated on 2,097 individuals from the Cardiovascular Risk in Young Finns study. Clusters were formed using the k-means method and their relationship with 115 variables from the areas of life habits, socioeconomic status and health was examined.

Results

Four clusters were identified for both genders. Individuals from Cluster I are characterized by high persistence, low extravagance and disorderliness. They have healthy life habits, and lowest scores in most of the measures for psychiatric disorders. Cluster II individuals are characterized by low harm avoidance and high novelty seeking. They report the best physical capacity and highest level of income, but also high rate of divorce, smoking, and alcohol consumption. Individuals from Cluster III are not characterized by any extreme characteristic. Individuals from Cluster IV are characterized by high levels of harm avoidance, low levels of exploratory excitability and attachment, and score the lowest in most measures of health and well-being.

Conclusions

This study shows that the temperament subscales do not distribute randomly but have an endogenous structure, and that these patterns have strong associations to health, life events, and well-being.

Proteomic, genomic and translational approaches identify CRMP1 for a role in schizophrenia and its underlying traits

Schizophrenia is a chronic illness of heterogenous biological origin. We hypothesized that, similar to chronic progressive brain conditions, persistent functional disturbances of neurons would result in disturbed proteostasis in the brains of schizophrenia patients, leading to increased abundance of specific misfolded, insoluble proteins. Identification of such proteins would facilitate the elucidation of molecular processes underlying these devastating conditions. We therefore generated antibodies against pooled insoluble proteome of post-mortem brains from schizophrenia patients in order to identify unique, disease-specific epitopes. We successfully identified such an epitope to be present on collapsin-response mediator protein 1 (CRMP1) in biochemically purified, insoluble brain fractions. A genetic association analysis for the CRMP1 gene in a large Finnish population cohort (n = 4651) corroborated the association of physical and social anhedonia with the CRMP1 locus in a DISC1 (Disrupted-in-schizophrenia 1)-dependent manner. Physical and social anhedonia are heritable traits, present as chronic, negative symptoms of schizophrenia and severe major depression, thus constituting serious vulnerability factors for mental disease. Strikingly, lymphoblastoid cell lines derived from schizophrenia patients mirrored aberrant CRMP1 immunoreactivity by showing an increase of CRMP1 expression, suggesting its potential role as a blood-based diagnostic marker. CRMP1 is a novel candidate protein for schizophrenia traits at the intersection of the reelin and DISC1 pathways that directly and functionally interacts with DISC1. We demonstrate the impact of an interdisciplinary approach where the identification of a disease-associated epitope in post-mortem brains, powered by a genetic association study, is rapidly translated into a potential blood-based diagnostic marker.

A genome-wide meta-analysis of association studies of Cloninger's Temperament Scales

Temperament has a strongly heritable component, yet multiple independent genome-wide studies have failed to identify significant genetic associations. We have assembled the largest sample to date of persons with genome-wide genotype data, who have been assessed with Cloninger's Temperament and Character Inventory. Sum scores for novelty seeking, harm avoidance, reward dependence and persistence have been measured in over 11,000 persons collected in four different cohorts. Our study had >80% power to identify genome-wide significant loci (P<1.25 × 10(-8), with correction for testing four scales) accounting for ≥0.4% of the phenotypic variance in temperament scales. Using meta-analysis techniques, gene-based tests and pathway analysis we have tested over 1.2 million single-nucleotide polymorphisms (SNPs) for association to each of the four temperament dimensions. We did not discover any SNPs, genes, or pathways to be significantly related to the four temperament dimensions, after correcting for multiple testing. Less than 1% of the variability in any temperament dimension appears to be accounted for by a risk score derived from the SNPs showing strongest association to the temperament dimensions. Elucidation of genetic loci significantly influencing temperament and personality will require potentially very large samples, and/or a more refined phenotype. Item response theory methodology may be a way to incorporate data from cohorts assessed with multiple personality instruments, and might be a method by which a large sample of a more refined phenotype could be acquired.

DISC1 conditioned GWAS for psychosis proneness in a large Finnish birth cohort

Background

Genetic evidence implicates the DISC1 gene in the etiology of a number of mental illnesses. Previously, we have reported association between DISC1 and measures of psychosis proneness, the Revised Social Anhedonia Scale (RSAS) and Revised Physical Anhedonia Scale (RPAS), in the Northern Finland Birth Cohort 1966 (NFBC66). As part of the studies of this Finnish birth cohort genome-wide association analysis has recently been performed.

Methodology

In the present study, we re-analyzed the genome-wide association data with regard to these two measures of psychosis proneness, conditioning on our previous DISC1 observation. From the original NFBC66 sample (N = 12 058), 4 561 individuals provided phenotype and genotype data. No markers were significant at the genome-wide level. However, several genes with biological relevance to mental illnesses were highlighted through loci displaying suggestive evidence for association (≥3 SNP with P<10E-4). These included the protein coding genes, CXCL3, KIAA1128, LCT, MED13L, TMCO7, TTN, and the micro RNA MIR620.

Conclusions

By conditioning a previous genome-wide association study on DISC1, we have been able to identify eight genes as associating to psychosis proneness. Further, these molecules predominantly link to the DISC1 pathway, strengthening the evidence for the role of this gene network in the etiology of mental illness. The use of quantitative measures of psychosis proneness in a large population cohort will make these findings, once verified; more generalized to a broad selection of disorders related to psychoses and psychosis proneness.

[Somatic involuntary hospitalization]

In a situation where the patient's own wish concerning her/his somatic treatment cannot be reliably assessed, the attending physician is obliged to treat the patient in the best possible way. Such situations include for instance unconsciousness, confusion and also severe mental disorders, such as psychoses. If the decision making capacity of the patient is lowered and immediate threat to somatic health is present, treatment decisions are made by the physician responsible for somatic care. The patient may be under somatic treatment also during involuntary psychiatric care.

Impact of temperament on depression and anxiety symptoms and depressive disorder in a population-based birth cohort

BACKGROUND

The aim of this study was to characterize at the population level how innate features of temperament relate to experience of depressive mood and anxiety, and whether these symptoms have separable temperamental backgrounds.

METHODS

The study subjects were 4773 members of the population-based Northern Finland Birth Cohort 1966, a culturally and genetically homogeneous study sample. Temperament was measured at age 31 using the temperament items of the Temperament and Character Inventory and a separate Pessimism score. Depressive mood was assessed based on a previous diagnosis of depressive disorder or symptoms of depression according to the Hopkins Symptom Check List - 25. Anxiety was assessed analogously.

RESULTS

High levels of Harm avoidance and Pessimism were related to both depressive mood (effect sizes; d=0.84 and d=1.25, respectively) and depressive disorder (d=0.68 and d=0.68, respectively). Of the dimensions of Harm avoidance, Anticipatory worry and Fatigability had the strongest effects. Symptoms of depression and anxiety showed very similar underlying temperament patterns.

LIMITATIONS

Although Harm avoidance and Pessimism appear to be important endophenotype candidates for depression and anxiety, their potential usefulness as endophenotypes, and whether they meet all the suggested criteria for endophenotypes will remain to be confirmed in future studies.

CONCLUSIONS

Personality characteristics of Pessimism and Harm avoidance, in particular its dimensions Anticipatory worry and Fatigability, are strongly related to symptoms of depression and anxiety as well as to depressive disorder in this population. These temperamental features may be used as dimensional susceptibility factors in etiological studies of depression, which may aid in the development of improved clinical practice.

Impact of the dopamine receptor gene family on temperament traits in a population-based birth cohort

Although the genetic determinants of personality have been intensively investigated especially since Cloninger proposed his psychobiological model of temperament and character, findings to date remain inconclusive and very few studies have addressed the topic in large population cohorts. In the current study we investigated one gene family in its entirety by addressing the role of all known dopamine receptor genes, DRD1-DRD5, on Cloninger's temperament traits in a Finnish population-based birth cohort. The study sample (n = 1,434) was ascertained from the Northern Finland Birth Cohort 1966 with over 5,000 study individuals tested at the age of 31 years. We utilized the genetic homogeneity and genealogical structure of this population to uncover putative effects of these genes on temperament traits at the population level. Our strategy utilizing a large birth cohort and its well established genealogical structure represents an optimal design for studying normally distributed traits. We also wished to provide a comprehensive view to one biologically relevant gene family instead of testing single candidate genes. We report evidence of association of several SNPs at the 5' end of dopamine receptor D2 (DRD2) with Novelty seeking (low) and Harm avoidance (high), and at the 3' end of DRD2 with Persistence. The strongest evidence of association emerged from females. Our study supports the involvement of the dopamine pathway in temperament traits, in particular underlining the role of DRD2 in Novelty seeking, Harm avoidance and Persistence.

Association between genes of Disrupted in schizophrenia 1 (DISC1) interactors and schizophrenia supports the role of the DISC1 pathway in the etiology of major mental illnesses

BACKGROUND

Disrupted in Schizophrenia 1 (DISC1) is currently one of the most interesting candidate genes for major mental illness, having been demonstrated to associate with schizophrenia, bipolar disorder, major depression, autism, and Asperger's syndrome. We have previously reported a DISC1 haplotype, HEP3, and an NDE1 spanning tag haplotype to associate to schizophrenia in Finnish schizophrenia families. Because both DISC1 and NDE1 display association in our study sample, we hypothesized that other genes interacting with DISC1 might also have a role in the etiology of schizophrenia.

METHODS

We selected 11 additional genes encoding components of the "DISC1 pathway" and studied these in our study sample of 476 families including 1857 genotyped individuals. We performed single nucleotide polymorphism (SNP) and haplotype association analyses in two independent sets of families. For markers and haplotypes found to be consistently associated in both sets, the overall significance was tested with the combined set of families.

RESULTS

We identified three SNPs to be associated with schizophrenia in PDE4D (rs1120303, p = .021), PDE4B (rs7412571, p = .018), and NDEL1 (rs17806986, p = .0038). Greater significance was observed with allelic haplotypes of PDE4D (p = .00084), PDE4B (p = .0022 and p = .029), and NDEL1 (p = .0027) that increased or decreased schizophrenia susceptibility.

CONCLUSIONS

Our findings with other converging lines of evidence support the underlying importance of DISC1-related molecular pathways in the etiology of schizophrenia and other major mental illnesses.

Association of variants in DISC1 with psychosis-related traits in a large population cohort

CONTEXT

There is an abundance of data from human genetic studies and animal models that implies a role for the disrupted in schizophrenia 1 gene (DISC1) in the etiology of schizophrenia and other major mental illnesses.

OBJECTIVE

To study the effect of previously identified risk alleles of DISC1 on quantitative intermediate phenotypes for psychosis in an unselected population.

DESIGN

We examined 41 single-nucleotide polymorphisms within DISC1 and performed tests of association with 4 quantitative phenotypes.

SETTING

Academic research.

PARTICIPANTS

Individuals from an unselected birth cohort in Finland. Originally, everyone born in the catchment area in 1966 (N = 12 058) was included in the study. Of these, 4651 (38.6%) attended the 31-year follow-up and could be included in the study.

MAIN OUTCOME MEASURES

Scores on 4 psychometric instruments selected to function as proxies for positive and negative aspects of psychotic disorders, including the Perceptual Aberration Scale, Revised Social Anhedonia Scale, Revised Physical Anhedonia Scale, and Schizoidia Scale by Golden and Meehl.

RESULTS

Carriers of the minor allele of marker rs821577 had significantly higher scores on social anhedonia (P < .001). The minor allele of marker rs821633 was strongly associated with lower scores on social anhedonia when analyzed dependent on the absence of the minor alleles of markers rs1538979 and rs821577 (P < .001).

CONCLUSIONS

Variants in DISC1 affect the level of social anhedonia, a cardinal symptom of schizophrenia in the general population. DISC1 might be more central to human psychological functioning than previously thought, as it seems to affect the degree to which people enjoy social interactions.

Replication of linkage on chromosome 7q22 and association of the regional Reelin gene with working memory in schizophrenia families

Schizophrenia is a common and complex mental disorder. Hereditary factors are important for its etiology, but despite linkage signals reported to several chromosomal regions in different populations, final identification of predisposing genes has remained a challenge. Utilizing a large family-based schizophrenia study sample from Finland, we have identified several linked loci: 1q32.2-q42, 2q, 4q31, 5q and 7q22. In this study, an independent sample of 352 nuclear schizophrenia families (n=1626) allowed replication of linkage on 7q21-32. In a sample of 245 nuclear families (n=1074) originating from the same geographical region as the families revealing the linkage, SNP and microsatellite association analyses of the four regional candidate genes, GRM3, RELN, SEMA3A and VGF, revealed no significant association to the clinical diagnosis of schizophrenia. Instead, quantifiable trait component analyses with neuropsychological endophenotypes available from 186 nuclear families (n=861) of the sample showed significant association to RELN variants for traits related to verbal (P=0.000003) and visual working memory (P=0.002), memory (P=0.002) and executive functioning (P=0.002). Trait-associated allele-positive subjects scored lower in the tests measuring working memory (P=0.0004-0.0000000004), memory (P=0.02-0.0001) and executive functioning (P=0.001). Our findings suggest that allelic variants of RELN contribute to the endophenotypes of schizophrenia.

Temperament profiles in personality disorders among a young adult population

The objective of this study was to describe the temperament dimension profiles assessed by the Temperament and Character Inventory (TCI) among young adults with the DSM-III-R personality disorder (PD). Our hypothesis was that PD clusters and separate PDs can be distinguished from one another by their specific temperament profiles. As a part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the cohort members living in the city of Oulu at the age of 31 years (n=1609) were invited to participate in a two-phase field study. The Structured Clinical Interview for DSM-III-R for PDs (SCID-II) was used as diagnostic instrument. The final study sample consisted of the 1311 subjects who had completed the Hopkins Symptom Check List-25 questionnaire for screening and had given a written informed consent. Of the 321 SCID interviewed subjects, 74 met the criteria for at least one PD and had completed the TCI. The mean TCI scores of subjects with PD and control subjects without PD (n=910) were compared. Low Novelty Seeking, high Harm Avoidance and low Reward Dependence characterized cluster A and C PDs. Subjects with a cluster B PD did not differ from controls, except for Novelty Seeking, which was high. The temperament dimensions could not distinguish different PDs very well, with the only exception of persons with obsessive-compulsive PD. PD clusters were associated with different profiles of temperament, lending some support for Cloninger's typology.

In vivo DA D(1) receptor selectivity of NNC 112 and SCH 23390

PURPOSE

[(11)C]NNC 112 and [(11)C]SCH 23390 are selective positron emission tomography (PET) tracers for visualizing dopamine D(1) receptors. It is known that both have some affinity for serotonin 2A receptors, but previous studies have suggested this is negligible compared to D(1) affinity. We sought to verify this property in vivo.

PROCEDURES

Two baboons were scanned to measure the selectivity of both tracers with a displacement paradigm. Four baboons were scanned to directly assess [(11)C] NNC 112 affinity for both receptors.

RESULTS

In vivo, D(1) to 5-HT(2A) selectivity is six to fourteenfold, not 100-fold as previously reported by other investigators.

CONCLUSION

We conclude that about 1/4 of the cortical signal of both [(11)C]NNC 112 and [(11)C]SCH 23390 is due to binding to 5-HT(2A) receptors. If confirmed in humans, this suggests caution should be exercised when drawing conclusions from studies using either tracer. These results also indicate the need for more selective tracers for the D(1) receptor.

The role of DTNBP1, NRG1, and AKT1 in the genetics of schizophrenia in Finland

Several putative schizophrenia susceptibility genes have recently been identified. Significant associations between schizophrenia and neuregulin 1 (NRG1) and dysbindin (DTNBP1) were first reported in 2002 and studies in several populations have since independently reported positive associations to these gene regions. Further, both tentative functional and genetic data have implicated the role of AKT1 in the genetic background of this disorder. However, findings have not been consistent in all populations. We investigated the allelic diversity of these three genes NRG1, DTNBP1 and AKT1 in a representative nation-wide study sample of 441 Finnish schizophrenia families consisting of 865 affected individuals, in order to assess their role in one of the largest population-based study samples. DTNBP1 and AKT1 failed to show evidence of association, whereas two SNPs in the 3' region of the NRG1 gene yielded suggestive evidence of association (p=0.012 and p=0.048) in family-based association analyses. Thus, our study does not indicate that AKT1 or DTNBP1 play a role in the etiology of schizophrenia in the Finnish population. Furthermore, results do not support a major role for NRG1, but we cannot completely exclude a minor role of this gene in the Finnish population.

Families with the risk allele of DISC1 reveal a link between schizophrenia and another component of the same molecular pathway, NDE1

We have previously reported a robust association between an allelic haplotype of 'Disrupted in Schizophrenia 1' (DISC1) and schizophrenia in a nationwide collection of Finnish schizophrenia families. This specific DISC1 allele was later identified to associate with visual working memory, selectively in males. DISC1 association to schizophrenia has since been replicated in multiple independent study samples from different populations. In this study, we conditioned our sample of Finnish families for the presence of the Finnish tentative risk allele for DISC1 and re-analyzed our genome-wide scan data of 443 markers on the basis of this stratification. Two additional loci displayed an evidence of linkage (LOD > 3) and included a locus on 16p13, proximal to the gene encoding NDE1, which has been shown to biologically interact with DISC1. Although none of the observed linkages remained significant after multiple test correction through simulation, further analysis of NDE1 revealed an association between a tag-haplotype and schizophrenia (P = 0.00046) specific to females, which proved to be significant (P = 0.011) after multiple test correction. Our finding would support the concept that initial gene findings in multifactorial diseases will assist in the identification of other components of complex genetic etiology. Notably, this and other converging lines of evidence underline the importance of DISC1-related functional pathways in the etiology of schizophrenia.

Temperament profiles and somatization--an epidemiological study of young adult people

OBJECTIVE

We assessed the temperament profiles of young adult somatizers in an epidemiological setting. We hypothesized that somatizers would have a characteristic temperament profile.

METHODS

The sample consisted of 984 subjects at the age of 31 years. Data on somatization were gathered from a review of all public health outpatient records. Subjects with four or more somatization symptoms according to the DSM-III-R criteria were classified as somatizers. Temperament profiles were assessed using the Temperament and Character Inventory (TCI).

RESULTS

Six males (1.3%) and 61 females (11.5%) met our criteria for somatization. Harm avoidance and reward dependence of the TCI profiles were associated with somatization symptoms in the whole sample. In logistic regression analysis, sex and psychological distress were associated with somatization but not with temperament profiles.

CONCLUSION

We did not find a characteristic temperament profile for somatizers. This finding is in contrast to suggestions that somatization is associated with temperament profiles.

Biodistribution and radiation dosimetry of the dopamine D2 ligand 11C-raclopride determined from human whole-body PET

Whole-body radiation dosimetry of 11C-raclopride was performed in healthy human volunteers.

METHODS

Subjects (n = 6) were scanned with PET. Subjects received single-bolus injections of 11C-raclopride (S-(-)-3,5-dichloro-N-[(1-ethyl-2-pyrrolidinyl)]methyl-2-hydroxy-6-methoxybenzamide) (533 +/- 104 MBq) and were scanned for approximately 110 min with a 2-dimensional whole-body protocol. Regions of interest were placed over all visually identifiable organs and time-activity curves were generated. Residence times were computed as the area under the curve of the time-activity curves, normalized to injected activities and standard values of organ volumes. Absorbed doses were computed according to the MIRD schema with MIRDOSE3.1 software.

RESULTS

Organs with the highest radiation burden were gallbladder wall, small intestine, liver, and urinary bladder wall.

CONCLUSION

On the basis of the estimated absorbed dose, the maximum allowable single study dose under U.S. federal regulations for studies performed under Radiation Drug Research Committee is 1.58 GBq (42.8 mCi). This is still considerably higher than the doses of 11C-raclopride commonly used in research PET (370-555 MBq).

A haplotype within the DISC1 gene is associated with visual memory functions in families with a high density of schizophrenia

We have previously reported evidence of linkage and association between markers on 1q42 and schizophrenia in a study sample of 498 multiply affected Finnish nuclear families, leading to the recent identification of four significantly associated haplotypes that specifically implicate the Translin-Associated Factor X (TRAX) and Disrupted in Schizophrenia 1 and 2 (DISC1 and DISC2) genes in the genetic etiology of schizophrenia. Previously, the DISC genes were found to be disrupted by a balanced translocation (1;11)(q42.1;q14.3) that cosegregated with schizophrenia and related disorders in a large Scottish pedigree. Interestingly, we also reported earlier suggestive linkage between endophenotypic quantitative traits of visual and verbal memory and microsatellite markers in close proximity to TRAX/DISC, on 1q41. Here, we tested if the identified allelic haplotypes of TRAX/DISC would be associated with visual and/or verbal memory function impairments that are known to aggregate with schizophrenia in families. One haplotype of DISC1, HEP3, displayed association with poorer performance on tests assessing short-term visual memory and attention. Analysis of affected and unaffected offspring separately revealed that both samples contribute to the observed association to visual working memory. These results provide genetic support to the view that the DISC1 gene contributes to sensitivity to schizophrenia and associated disturbances and affects short-term visual memory functions. This finding should stimulate studies aiming at the molecular characterization of how the specific alleles of DISC1 affect the visual memory functions and eventually participates in the development of schizophrenia.

Measurement of the proportion of D2 receptors configured in state of high affinity for agonists in vivo: a positron emission tomography study using [11C]N-propyl-norapomorphine and [11C]raclopride in baboons

Dopamine D2 receptors are configured in interconvertible states of high (D(2 high)) or low (D(2 low)) affinity for agonists. The in vivo proportion of sites in high-affinity state remains poorly documented. Previous studies have established the D2 agonist [11C]N-propyl-norapomorphine (NPA) as a suitable positron emission tomography radiotracer for imaging D(2 high) in the living brain. To elucidate the proportion of D2 receptors configured in D(2 high) states in vivo, imaging studies were conducted in three baboons with both [11C]NPA and the D2 receptor antagonist [11C]raclopride. These studies were performed under noncarrier- and carrier-added conditions, to compare the Bmax of [11C]NPA and [11C]raclopride in the same animals. [11C]raclopride in vivo KD and Bmax were 1.59 +/- 0.28 nM (n = 3) and 27.3 +/- 3.9 nM (n = 3), respectively. The in vivo KD of [11C]NPA was 0.16 +/- 0.01 nM (n = 3), consistent with its affinity for D(2 high) reported in vitro. The maximal density of sites for [11C]NPA was 21.6 +/- 2.8 nM (n = 3), i.e., 79% of the [11C]raclopride Bmax. This result suggested that 79% of D2 receptors are configured as D(2 high) in vivo. This large proportion of D(2 high) sites might explain the vulnerability of D2 radiotracers to competition by endogenous dopamine, and is consistent with a previous report that the in vivo binding of agonist radiotracer [11C]NPA is more vulnerable to competition by endogenous dopamine than that of antagonist radiotracer [11C]raclopride.

The new PET imaging agent [11C]AFE is a selective serotonin transporter ligand with fast brain uptake kinetics

A new positron emission tomography (PET) radioligand for the serotonin transporter (SERT), [(11)C]2-[2-[[(dimethylamino)methyl]phenyl]thio]-5-(2-fluoroethyl)phenylamine ([(11)C]AFE, 12), was synthesized and evaluated in vivo in rats and baboons. [(11)C]AFE (12) was prepared from its monomethylamino precursor 11 by reaction with high specific activity [(11)C]methyl triflate. Radiochemical yield was 32+/-17% based on [(11)C]methyl triflate (n=6) and specific activity was 1670+/-864 Ci/mmol at end of synthesis (EOS, n=6). Binding assays indicated that AFE displays high affinity for SERT (K(i)=1.80 nM for hSERT) and lower affinity for norepinephrine transporter (K(i)=946 nM for hNET) or dopamine transporter (K(i)>10,000 nM for hDAT). In addition, AFE displays negligible binding affinities for other serotonin and dopamine receptors, indicating an excellent binding selectivity in vitro. Biodistribution studies in rats indicated that [(11)C]AFE enters the brain readily and localizes in regions known to contain high concentrations of SERT, such as the thalamus, hypothalamus, frontal cortex and striatum. Moreover, such binding in SERT-rich brain regions is reduced significantly by pretreatment with either citalopram or the cold compound itself, but not by nisoxetine or GBR 12935, thus demonstrating that [(11)C]AFE binding in the rat brain is saturable, specific and selective for the SERT. Imaging experiments in baboons indicated that the uptake pattern of [(11)C]AFE is consistent with the known distribution of SERT in the baboon brain, with high levels of radioactivity detected in the midbrain and thalamus, moderate levels in the hippocampus and striatum and low levels in the cortical regions. The uptake kinetics of [(11)C]AFE in the baboon brain is rapid, with activity in the midbrain and thalamus peaking at 15-40 min postinjection. Pretreatment of the baboon with citalopram (4 mg/kg) 20 min before radioactivity injection reduced the binding of [(11)C]AFE in all SERT-containing brain regions to the level in the cerebellum. Kinetic analysis revealed that in all brain regions examined, [(11)C]AFE specific-to-nonspecific partition coefficients (V(3)'') are similar to those of [(11)C]McN5652 and [(11)C]2-[2-[[(dimethylamino)methyl]phenyl]thio]-5-fluorophenylamine ([(11)C]AFA), but lower than those of [(11)C]2-[2-[[(dimethylamino)methyl]phenyl]thio]-5-fluoromethylphenylamine ([(11)C]AFM) or [(11)C]DASB. In summary, [(11)C]AFE appears to be a PET radioligand with fast brain uptake kinetics and can be used for the visualization and quantification of SERT in vivo.

Novelty seeking: interaction between parental alcohol use and dopamine D4 receptor gene exon III polymorphism over 17 years

Recent meta-analyses have questioned the association between the dopamine receptor D4 (DRD4) gene polymorphism and the temperament trait of novelty seeking, and proposed an interaction between the polymorphism and other factors. We wanted to test whether parental alcohol use during childhood moderated the effect of an offspring dopamine receptor gene (DRD4) polymorphism on the temperament trait of novelty seeking in adulthood. A population-based sample of children and adolescents (n=2149) and their parents was examined in 1980 and 1983 on parental alcohol use and rearing practices. In 1997, study participants completed the Temperament and Character Inventory for the novelty-seeking temperament trait, and a subsample (n=150) was genotyped for the DRD4 exon III polymorphism. For the participants with the father, but not the mother, reporting more frequent alcohol consumption or drunkenness in examinations 17 and/or 14 years before the novelty-seeking assessment, an association between the short (two- or five-repeat) alleles of the DRD4 gene and extremely high novelty-seeking scores was observed. When the father reported less frequent alcohol consumption or drunkenness, the genotype was not associated with novelty seeking. The association remained after controlling for sex, age, and maternal child-rearing. These results provide preliminary information on gene-environment interaction on the temperament trait of novelty seeking and may partly explain the heterogeneity of findings concerning the association between DRD4 polymorphisms and novelty seeking.

Replication of 1q42 linkage in Finnish schizophrenia pedigrees

Chromosome 1q has been implicated in the etiology of schizophrenia in several independent studies. However, the peak linkage findings have been dispersed over a large chromosomal region, with negative findings in this region also being reported. Our group has previously observed linkage on chromosome 1q42, maximizing within the DISC1 gene, which has also been implied in the etiology of schizophrenia based on functional studies. In the study presented here, we genotyped 300 polymorphic markers on chromosome 1 using a study sample of 70 families with multiple individuals affected with schizophrenia or related conditions, independent of the study samples in our previous reports. We again found evidence for linkage on 1q42 maximizing within the DISC1 gene (rs1000731, lod=2.70). Further, a haplotype containing the most strongly linked markers showed some evidence of association with the disease. This replicates the previous linkage finding in the same region and constitutes supportive evidence for a susceptibility gene in this region.

A large population cohort provides normative data for investigation of temperament

OBJECTIVE

We evaluated the psychometric properties of widely used scales for assessing temperament in a large birth cohort. We simultaneously compared the properties of the temperament dimensions of the Tridimensional Personality Questionnaire (TPQ) and of the Temperament and Character Inventory (TCI).

METHOD

As part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the TPQ and TCI temperament questions were filled in by 4349 subjects (1974 males, 2375 males). Factor analysis and Cronbach's alpha were used to explore the psychometric properties of the scales.

RESULTS

Of the three higher-order dimensions the reward dependence (RD) was the only one performing poorly in our study sample. Cronbach's alpha was higher in the TCI than in the TPQ.

CONCLUSION

The results indicate good performance of the TCI and TPQ. Factor analysis support adoption of four temperament dimensions and suggest that developmental work is still needed in the RD dimension.

Nature and nurture in novelty seeking

A sample of children (n=92), derived from a representative population sample of healthy young Finns (n=2149), was studied from childhood to adulthood over 14 years to determine whether the childhood environment moderated the effect of dopamine receptor gene (DRD4) polymorphism on novelty seeking (NS). A significant interaction between the DRD4 alleles and environmental variables was observed. When the childhood-rearing environment was more hostile (emotionally distant, low tolerance of the child's normal activity, and strict discipline), the participants carrying any two- or five-repeat alleles of the DRD4 gene had a significantly greater risk of exhibiting NS scores that were above the 10th percentile on a population distribution of 2149 adult Finnish women and men. The genotype had no effects on NS when the childhood environment was more favorable. Although the results are preliminary, pending replication, they nevertheless provide important information on the long-term effects of nurture and nature on NS temperament.

Haplotype transmission analysis provides evidence of association for DISC1 to schizophrenia and suggests sex-dependent effects

We have previously reported a linkage peak on 1q42 in a Finnish schizophrenia sample. In this study we genotyped 28 single nucleotide polymorphisms (SNPs) from 1q42 covering the three candidate genes TRAX, DISC1 and DISC2, using a study sample of 458 Finnish families ascertained for schizophrenia. Two-point and haplotype association analysis revealed a significant region of interest within the DISC1 gene. A common haplotype (HEP3) was observed to be significantly under-transmitted to affected individuals (P=0.0031). HEP3 represents a two SNP haplotype spanning from intron 1 to exon 2 of DISC1. This haplotype also displayed sex differences in transmission distortion, the under-transmission being significant only to affected females (P=0.00024). Three other regions of interest were observed in the TRAX and DISC genes. However, analysis of only those families with complete genotype information specifically highlights the HEP3 haplotype as a true observation. The finding of a common under-transmitted SNP haplotype might imply that this particular allele offers some protection from the development of schizophrenia. Analysis of component-traits of schizophrenia, derived from the Operational Criteria Checklist of Psychotic Illness (OCCPI), displayed association of HEP3 to features of the general phenotype of schizophrenia, including traits representing delusions, hallucinations and negative symptoms. This study provides further evidence for the hypothesis that the DISC1 gene is involved in the aetiology of schizophrenia, and implies a putative sex difference for the effect of the gene. Our findings would also encourage more detailed analyses of the effect of DISC1 on the component-traits of schizophrenia.

No association between micrometer-sized particles in human cerebrospinal fluid and schizophrenia

The pathogenetic processes underlying schizophrenia are unknown, but the organic changes observed in the brain tissue of schizophrenic patients suggest the possibility of findings also in the cerebrospinal fluid (CSF) of patients suffering from this disorder. In a recently published study micrometer-sized spherical particles in CSF were isolated from significantly more schizophrenic patients compared to controls. The functional importance of these particles is unknown, but if replicated in independent study samples they could function as trait markers and spur further investigations. We analyzed CSF samples from five patients with a diagnosis of schizophrenia, nine patients with chronic pain syndrome and six healthy controls with scanning electron microscopy in accordance with the protocol described in the original report. Similar particles were identified as in the previous study, but they were not associated with disease status (P=1.00). It cannot be excluded that these divergent results are due to methodological differences, but presently the most parsimonious explanation would be that the original finding was a false positive result. More investigation is needed to clarify the source and relevance of these particles.

An MDL method for finding haplotype blocks and for estimating the strength of haplotype block boundaries

We describe a new method for finding haplotype blocks based on the use of the minimum description length principle. We give a rigorous definition of the quality of a segmentation of a genomic region into blocks, and describe a dynamic programming algorithm for finding the optimal segmentation with respect to this measure. We also describe a method for finding the probability of a block boundary for each pair of adjacent markers: this gives a tool for evaluating the significance of each block boundary. We have applied the method to the published data of Daly et al. The results are in relatively good agreement with the published results, but also show clear differences in the predicted block boundaries and their strengths. We also give results on the block structure in population isolates.