Obsessive-Compulsive Disorder,Psychosis, and Bipolarity: A Longitudinal Cohort and Multigenerational Family Study

Obsessive-compulsive disorder (OCD) often co-occurs with psychotic and bipolar disorders; this comorbidity complicates the clinical management of these conditions. In this population-based longitudinal and multigenerational family study, we examined the patterns of comorbidity, longitudinal risks, and shared familial risks between these disorders. Participants were individuals with a diagnosis of OCD (n = 19814), schizophrenia (n = 58336), bipolar disorder (n = 48180), and schizoaffective disorder (n = 14904) included in the Swedish Patient Register between January 1969 and December 2009; their first-, second-, and third-degree relatives; and population-matched (1:10 ratio) unaffected comparison individuals and their relatives. The Swedish Prescribed Drug Register was used to control for the potential effect of medication in the longitudinal analyses. Individuals with OCD had a 12-fold increased risk of having a comorbid diagnosis of schizophrenia and a 13-fold increased risk of bipolar disorder and schizoaffective disorder. Longitudinal analyses showed that individuals first diagnosed with OCD had an increased risk for later diagnosis of all other disorders, and vice versa. The risk of bipolar disorder was reduced, but not eliminated, when the use of selective serotonin reuptake inhibitors was adjusted for. OCD-unaffected first-, second-, and third-degree relatives of probands with OCD had a significantly increased risk for all 3 disorders; the magnitude of this risk decreased as the genetic distance increased. We conclude that OCD is etiologically related to both schizophrenia spectrum and bipolar disorders. The results have implications for current gene-searching efforts and for clinical practice.Key words: OCD, schizophrenia, schizoaffective disorder, bipolar disorder, genetic epidemiology     

Investigating Direct and Indirect Genetic Effects in Attention-Deficit/Hyperactivity Disorder Using Parent-Offspring Trios

BackgroundAttention-deficit/hyperactivity disorder (ADHD) is highly heritable, but little is known about the relative effects of transmitted (i.e., direct) and nontransmitted (i.e., indirect) common variant risks. Using parent-offspring trios, we tested whether polygenic liability for neurodevelopmental and psychiatric disorders and lower cognitive ability is overtransmitted to ADHD probands. We also tested for indirect or genetic nurture effects by examining whether nontransmitted ADHD polygenic liability is elevated. Finally, we examined whether complete trios are representative of the clinical ADHD population.MethodsPolygenic risk scores (PRSs) for ADHD, anxiety, autism, bipolar disorder, depression, obsessive-compulsive disorder, schizophrenia, Tourette syndrome, and cognitive ability were calculated in UK control subjects (n = 5081), UK probands with ADHD (n = 857), their biological parents (n = 328 trios), and also a replication sample of 844 ADHD trios.ResultsADHD PRSs were overtransmitted and cognitive ability and obsessive-compulsive disorder PRSs were undertransmitted. These results were independently replicated. Overtransmission of polygenic liability was not observed for other disorders. Nontransmitted alleles were not enriched for ADHD liability compared with control subjects. Probands from incomplete trios had more hyperactive-impulsive and conduct disorder symptoms, lower IQ, and lower socioeconomic status than complete trios. PRS did not vary by trio status.ConclusionsThe results support direct transmission of polygenic liability for ADHD and cognitive ability from parents to offspring, but not for other neurodevelopmental/psychiatric disorders. They also suggest that nontransmitted neurodevelopmental/psychiatric parental alleles do not contribute indirectly to ADHD via genetic nurture. Furthermore, ascertainment of complete ADHD trios may be nonrandom, in terms of demographic and clinical factors.     

A Nationwide Cohort Study of Nonrandom Mating in Schizophrenia and Bipolar Disorder

Nonrandom mating in parents with schizophrenia or bipolar disorder increases the population-level genetic variance among the offspring generation and creates familial (risk) environments likely to be shaped by specific conditions. The objective of this study was to investigate the occurrence of mental disorder and levels of cognitive and social functioning in individuals who have children by partners with schizophrenia or bipolar disorder compared to controls. The Danish High Risk and Resilience Study VIA 7 is a population-based cohort study conducted in Denmark between 2013 and 2016. This study focus on parents diagnosed with schizophrenia (n = 150) or bipolar disorder (n = 100) and control parents (n = 182), as well as their partners without schizophrenia or bipolar disorder (n = 440). We used linear mixed-effect models, and main outcomes were mental disorders, intelligence, processing speed, verbal working memory, and social functioning. We found that parents having children by a partner with schizophrenia or bipolar disorder more often fulfilled the criteria for a mental disorder and had poorer social functioning compared to parents having children by a partner without schizophrenia or bipolar disorder. Furthermore, parents having children by a partner with schizophrenia performed poorer on processing speed compared to parents in the control group. The presence of nonrandom mating found in this study has implications for our understanding of familial transmission of these disorders and our findings should be considered in future investigations of potential risk factors for children with a parent with schizophrenia or bipolar disorder.     

Replicating extensive brain structural heterogeneity in individuals with schizophrenia and bipolar disorder

Identifying brain processes involved in the risk and development of mental disorders is a major aim. We recently reported substantial interindividual heterogeneity in brain structural aberrations among patients with schizophrenia and bipolar disorder. Estimating the normative range of voxel‐based morphometry (VBM) data among healthy individuals using a Gaussian process regression (GPR) enables us to map individual deviations from the healthy range in unseen datasets. Here, we aim to replicate our previous results in two independent samples of patients with schizophrenia (n1 = 94; n2 = 105), bipolar disorder (n1 = 116; n2 = 61), and healthy individuals (n1 = 400; n2 = 312). In line with previous findings with exception of the cerebellum our results revealed robust group level differences between patients and healthy individuals, yet only a small proportion of patients with schizophrenia or bipolar disorder exhibited extreme negative deviations from normality in the same brain regions. These direct replications support that group level‐differences in brain structure disguise considerable individual differences in brain aberrations, with important implications for the interpretation and generalization of group‐level brain imaging findings to the individual with a mental disorder.     

Abnormalities in the fatty acid composition of the postmortem entorhinal cortex of patients with schizophrenia,bipolar disorder,and major depressive disorder

Previous studies of postmortem orbitofrontal cortex have shown abnormalities in levels of n−3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA), in individuals with schizophrenia, bipolar disorder, and major depressive disorder (MDD). We have previously measured PUFA levels in the postmortem hippocampus from patients with schizophrenia or bipolar disorder and control subjects; however, we found no significant differences between the groups except for small changes in n−6 PUFAs. Furthermore, our study of the postmortem amygdala showed no significant differences in major PUFAs in individuals with schizophrenia, bipolar disorder, or MDD in comparison with controls. In the present study, we investigated whether there were any changes in PUFAs in the entorhinal cortexes of patients with schizophrenia (n=15), bipolar disorder (n=15), or MDD (n=15) compared with unaffected controls (n=15) matched for characteristics including age and sex. In contrast to previous studies of the orbitofrontal cortex and hippocampus, we found no significant differences in major PUFAs. However, we found a 34.3% decrease in docosapentaenoic acid (DPA) (22:5n−3) in patients with MDD and an 8.7% decrease in docosatetraenoic acid (22:4n−6) in those with schizophrenia, compared with controls. Changes in PUFAs in patients with these psychiatric disorders may be specific to certain brain regions.     

The relationship between syndromes of the psychotic illness and familial liability to schizophrenia and major mood disorders

BACKGROUND: Previous studies examining the relationship between psychopathological syndromes of the psychotic illness and familial liability to schizophrenia and mood disorders have obtained inconclusive results. The aim of this study is to further examine this issue by analyzing a large sample of psychotic probands and their first-degree relatives. METHODS: The sample was composed of 660 psychotic inpatients and their 2987 first-degree relatives. Probands were assessed for index episode and lifetime symptoms, while relatives were assessed for lifetime diagnosis of schizophrenia and major mood disorders. Associations between factor-analysis derived syndromes in probands and familial loading for schizophrenia and major mood disorders were tested. RESULTS: Familial morbid risk of schizophrenia was predicted by the negative syndrome in probands and familial morbid risk of mood disorders was predicted by mania, depression and catatonia syndromes in probands. This association pattern was relatively independent of type of symptom rating (index episode or lifetime) and probands' diagnosis of schizophrenia or major mood disorder. Familial loading for schizophrenia and mood disorders cut-across the DSM-IV categories of psychotic disorders in probands. CONCLUSION: From a dimensional perspective, the negative syndrome is related to familial liability to develop schizophrenia. Mania, depression and catatonia syndromes are related to the familial liability to develop major mood disorders. Categories of psychotic disorders are on a continuum of familial liability to schizophrenia and major mood disorders.     

Associations between major psychiatric disorder polygenic risk scores and blood-based markers in UK biobank

Major depressive disorder (MDD), schizophrenia (SCZ), and bipolar disorder (BD) have both shared and discrete genetic risk factors, and are associated with peripheral abnormalities. The relationships between such genetic architectures and blood-based markers are, however, unclear.We investigated relationships between polygenic risk scores (PRS) for these disorders and peripheral markers in the UK Biobank cohort. We calculated polygenic risk scores for n = 367,329 (MDD PRS), n = 366,465 (SCZ PRS), and n = 366,383 (BD PRS) UK Biobank cohort subjects. We then examined associations between disorder PRS and 58 inflammatory/immune, hematological, bone, cardiovascular, hormone, liver, renal and diabetes-associated blood markers using two generalized linear regression models: ‘minimally adjusted’ controlling for variables such as age and sex, and ‘fully adjusted’ including additional lifestyle covariates: BMI, alcohol and smoking status, and medication intake.There were 38/58 MDD PRS, 32/58 SCZ PRS, and 20/58 BD PRS-blood marker associations detected for our minimally adjusted model. Of these, 13/38 (MDD PRS), 14/32 (SCZ PRS), and 10/20 (BD PRS) associations remained significant after controlling for lifestyle factors. Many were disorder-specific, with 8/13 unique MDD PRS associations identified. Several disorder-specific associations for MDD and SCZ were immune-related, with mostly positive and negative associations identified for MDD and SCZ PRS respectively.This study suggests that MDD, SCZ and BD have both shared and distinct peripheral markers associated with disorder-specific genetic risk. The results also implicate inflammatory dysfunction in MDD and SCZ, albeit with differences in patterns between the two conditions, and enrich our understanding of potential underlying pathophysiological mechanisms in major psychiatric disorders.     

Hospital Presentation for Self-Harm in Youth as a Risk Marker for Later Psychotic and Bipolar Disorders: A Cohort Study of 59 476 Finns

Expanding clinical strategies to identify high risk groups for psychotic and bipolar disorders is a research priority. Considering that individuals diagnosed with psychotic and bipolar disorder are at high risk of self-harm, we hypothesised the reverse order relationship would also be true (ie, self-harm would predict psychotic/bipolar disorder). Specifically, we hypothesised that hospital presentation for self-harm would be a marker of high risk for subsequent development of psychotic/bipolar disorder and sought to test this hypothesis in a large population sample. This prospective register-based study included everyone born in Finland in 1987, followed until age 28 years (N = 59 476). We identified all hospital records of self-harm presentations, as well as all ICD-10 healthcare registrations of first diagnoses of psychotic and bipolar disorders. Cox proportional hazards models were used to assess the relationship between self-harm and psychotic/bipolar disorders. Of all individuals who presented to hospital with self-harm (n = 481), 12.8% went on to receive a diagnosis of psychosis (hazard ratio [HR] = 6.03, 95% confidence interval [CI] 4.56–7.98) and 9.4% a diagnosis of bipolar disorder (HR = 7.85, 95% CI 5.73–10.76) by age 28 years. Younger age of first self-harm presentation was associated with higher risk—for individuals who presented before age 18 years, 29.1% developed a psychotic or bipolar disorder by age 28 years. Young people who present to hospital with self-harm are at high risk of future psychotic and bipolar disorders. They represent an important cohort for the prevention of serious mental illness.     

Risk of Mental Illness in Offspring of Parents With Schizophrenia,Bipolar Disorder,and Major Depressive Disorder: A Meta-Analysis of Family High-Risk Studies

Objective: Offspring of parents with severe mental illness (SMI; schizophrenia, bipolar disorder, major depressive disorder) are at an increased risk of developing mental illness. We aimed to quantify the risk of mental disorders in offspring and determine whether increased risk extends beyond the disorder present in the parent. Method: Meta-analyses of absolute and relative rates of mental disorders in offspring of parents with schizophrenia, bipolar disorder, or depression in family high-risk studies published by December 2012. Results: We included 33 studies with 3863 offspring of parents with SMI and 3158 control offspring. Offspring of parents with SMI had a 32% probability of developing SMI (95% CI: 24%–42%) by adulthood (age >20). This risk was more than twice that of control offspring (risk ratio [RR] 2.52; 95% CI 2.08–3.06, P < .001). High-risk offspring had a significantly increased rate of the disorder present in the parent (RR = 3.59; 95% CI: 2.57–5.02, P < .001) and of other types of SMI (RR = 1.92; 95% CI: 1.48–2.49, P < .001). The risk of mood disorders was significantly increased among offspring of parents with schizophrenia (RR = 1.62; 95% CI: 1.02–2.58; P = .042). The risk of schizophrenia was significantly increased in offspring of parents with bipolar disorder (RR = 6.42; 95% CI: 2.20–18.78, P < .001) but not among offspring of parents with depression (RR = 1.71; 95% CI: 0.19–15.16, P = .631). Conclusions: Offspring of parents with SMI are at increased risk for a range of psychiatric disorders and one third of them may develop a SMI by early adulthood.Key words: schizophrenia, bipolar disorder, depression, offspring, meta-analysis     

Theta Phase Synchrony Is Sensitive to Corollary Discharge Abnormalities in Early Illness Schizophrenia but Not in the Psychosis Risk Syndrome

BackgroundPrior studies have shown that the auditory N1 event-related potential component elicited by self-generated vocalizations is reduced relative to played back vocalizations, putatively reflecting a corollary discharge mechanism. Schizophrenia patients and psychosis risk syndrome (PRS) youth show deficient N1 suppression during vocalization, consistent with corollary discharge dysfunction. Because N1 is an admixture of theta (4–7 Hz) power and phase synchrony, we examined their contributions to N1 suppression during vocalization, as well as their sensitivity, relative to N1, to corollary discharge dysfunction in schizophrenia and PRS individuals.MethodsTheta phase and power values were extracted from electroencephalography data acquired from PRS youth (n = 71), early illness schizophrenia patients (ESZ; n = 84), and healthy controls (HCs; n = 103) as they said “ah” (Talk) and then listened to the playback of their vocalizations (Listen). A principal component analysis extracted theta intertrial coherence (ITC; phase consistency) and event-related spectral power, peaking in the N1 latency range. Talk–Listen suppression scores were analyzed.ResultsTalk–Listen suppression was greater for theta ITC (Cohen’s d = 1.46) than for N1 in HC (d = 0.63). Both were deficient in ESZ, but only N1 suppression was deficient in PRS. When deprived of variance shared with theta ITC suppression, N1 suppression no longer differentiated ESZ and PRS individuals from HC. Deficits in theta ITC suppression were correlated with delusions (P = .007) in ESZ. Theta power suppression did not differentiate groups.ConclusionsTheta ITC-suppression during vocalization is a more sensitive index of corollary discharge-mediated auditory cortical suppression than N1 suppression and is more sensitive to corollary discharge dysfunction in ESZ than in PRS individuals.     

Neurocognitive Dysfunction in Bipolar and Schizophrenia Spectrum Disorders Depends on History of Psychosis Rather Than Diagnostic Group

Objectives: Neurocognitive dysfunction is milder in bipolar disorders than in schizophrenia spectrum disorders, supporting a dimensional approach to severe mental disorders. The aim of this study was to investigate the role of lifetime history of psychosis for neurocognitive functioning across these disorders. We asked whether neurocognitive dysfunction in bipolar and schizophrenia spectrum disorders depends more on history of psychosis than diagnostic category or subtype. Methods: A sample of individuals with schizophrenia (n = 102), schizoaffective disorder (n = 27), and bipolar disorder (I or II) with history of psychosis (n = 75) and without history of psychosis (n = 61) and healthy controls (n = 280), from a large ongoing study on severe mental disorder, were included. Neurocognitive function was measured with a comprehensive neuropsychological test battery. Results: Compared with controls, all 3 groups with a history of psychosis performed poorer across neurocognitive measures, while the bipolar group without a history of psychosis was only impaired on a measure of processing speed. The groups with a history of psychosis did not differ from each other but performed poorer than the group without a history of psychosis on a number of neurocognitive measures. These neurocognitive group differences were of a magnitude expected to have clinical significance. In the bipolar sample, history of psychosis explained more of the neurocognitive variance than bipolar diagnostic subtype. Conclusions: Our findings suggest that neurocognitive dysfunction in bipolar and schizophrenia spectrum disorders is determined more by history of psychosis than by Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) diagnostic category or subtype, supporting a more dimensional approach in future diagnostic systems.     

Pituitary volume in unaffected relatives of patients with schizophrenia and bipolar disorder

BACKGROUND: Hypothalamic-pituitary-adrenal (HPA) axis hyperactivity has been demonstrated in both schizophrenia and bipolar disorder, but the mechanisms underlying this abnormality are still unclear. Enlarged pituitary volume has been recently reported in patients with first episode psychosis and been interpreted as a consequence of an increased activation of the HPA axis. The aim of this study was to assess the contribution of familial liability to pituitary volume in schizophrenia and bipolar disorder. Pituitary volume may be an indirect measure of HPA axis activity. METHODS: MRI brain scans and measurements of pituitary volumes were obtained for 183 subjects: 26 patients with established schizophrenia or schizoaffective disorder, 44 of their unaffected first-degree relatives (22 familial schizophrenia, 22 non-familial schizophrenia), 29 patients with established bipolar disorder, 38 of their unaffected first-degree relatives, and 46 healthy comparison subjects. RESULTS: We found a significantly larger pituitary volume (effect size=0.7) in unaffected relatives of patients with schizophrenia compared with controls (p=0.002); the pituitary was even larger in relatives of patients with familial schizophrenia (effect size=0.8, p=0.005). We did not find a significant difference in pituitary volume when comparing the relatives of bipolar patients with controls. Among patients, those with schizophrenia who were receiving prolactin-elevating antipsychotics had an increased pituitary volume compared with controls (effect size=1.0, p=0.006). CONCLUSIONS: These results suggest that the larger pituitary volume previously reported in first episode schizophrenia could be partly due to a genetic susceptibility to over-activate the HPA axis.     

Medical Co-morbidities Among Patients with Severe Mental Illnesses in a Community Health Facility in Nigeria

To examine prevalence of medical comorbidity (MCM) in schizophrenia (n?=?1310) and in bipolar disorder (n?=?1307) and the association of high burden of MCM (≥3 MCM) with duration of untreated illness, number of episodes, functioning, poly-medication and lifetime hospitalization for the mental disorder. Participants were recruited from a private psychiatric facility in Ibadan, Nigeria between 2004 and 2013 and enquiry made about the lifetime occurrence of 20 common chronic diseases including common tropical diseases. Psychiatric diagnosis was made using the Structured Clinical Interview for DSM IV Axis I disorder (SCID). Except for nutritional anemia, dermatitis and intestinal Helminthiasis, patients with schizophrenia were not at higher odds of reporting MCM than those with bipolar disorder. DUI?≥2 years, episodes of illness?≥3, being on multiple neuroleptics and history of previous hospitalization were significantly associated with high burden of MCM in schizophrenia and episodes of illness?≥3, reduced functioning and history of previous hospitalization with bipolar disorder. Schizophrenia and bipolar disorder are associated with high rates of medical comorbidity. Treatment of this medical comorbidity is essential in order to improve the outcomes for patients with bipolar disorder and schizophrenia.     

Abnormal neural functions associated with motor inhibition deficits in schizophrenia and bipolar disorder

Deficits in response inhibition have been observed in schizophrenia and bipolar disorder; however, the neural origins of the abnormalities and their relevance to genetic liability for psychosis are unknown. We used a stop‐signal task to examine motor inhibition and associated neural processes in schizophrenia patients (n = 57), bipolar disorder patients (n = 21), first‐degree biological relatives of patients with schizophrenia (n = 34), and healthy controls (n = 56). Schizophrenia patients demonstrated motor control deficits reflected in longer stop‐signal reaction times and elongated reaction times. With the possibility of needing to inhibit a button press, both schizophrenia and bipolar disorder patients showed diminished reductions of the P300 brain response and only the healthy controls demonstrated adjustments in response execution time, as measured by response‐locked lateralized readiness potentials. Schizotypal traits in the biological relatives were associated with less P300 modulation consistent with the motor‐related anomalies being associated with subtle schizophrenia‐spectrum symptomatology in family members. The two patient groups had elongated response selection processes as manifest in the delayed onset of the stimulus‐locked lateralized readiness potential. The bipolar disorder group was unique in showing significantly diminished neural responses to the stop‐signal to inhibit a response. Antipsychotic medication dosage was related to worse motor inhibition, thus motor inhibition deficits in schizophrenia may be partially explained by the effect of pharmacological agents. Failed modulation of brain processes in relation to response inhibition probability and the lengthening of motor response selection appear to be transdiagnostic abnormalities spanning schizophrenia and bipolar disorder.     

The epidemiology of bipolar disorder: sociodemographic, disability and service utilization data from the Australian National Study of Low Prevalence (Psychotic) Disorders

OBJECTIVES: Data from the Australian National Study of Low Prevalence (Psychotic) Disorders were used to describe the clinical and sociodemographic profile of individuals with bipolar disorder, their levels of impairment and disability, and use of medication and treatment services. METHODS: A 1-month census of contacts with mental health services, private psychiatric and general practices, as well as contact points in marginalized settings, was conducted in a national catchment of 1.1 million adults. The census yielded 3,800 individuals who screened positive for psychosis, of whom a random sample of 980 were administered a comprehensive semi-structured interview schedule. Results are presented on 112 persons with an ICD-10 diagnosis of bipolar disorder. RESULTS: Overall, 69.6% of the 112 persons who met the ICD-10 criteria for bipolar disorder reported a recurrent episodic illness, 25.0% had a chronic course without clear remissions, and 5.4% had a single episode of mania. Assessed on a lifetime basis, suicidal ideation was common (78.6%) and levels of drug and alcohol abuse/dependence were high (32.1%). The majority (84.8%) had had at least one contact with inpatient, outpatient or emergency services in the previous year. Those with serious impairment had levels of service utilization similar to the rest of the sample, but were more likely to report a poorer quality of life and unmet service needs. While the percentage experiencing social and occupational dysfunction was substantial and similar for both sexes, women appeared to be better integrated socially than men. Comparisons with schizophrenia patients within the same survey sample highlighted less chronic impairment but equal or greater utilization of services by bipolar patients. CONCLUSIONS: Despite low levels of chronicity, the burden of social disablement associated with bipolar disorder is high. The data suggest a number of important gaps in the provision of services for this predominantly treated population.     

An auditory processing abnormality specific to liability for schizophrenia

Abnormal brain activity during the processing of simple sounds is evident in individuals with increased genetic liability for schizophrenia; however, the diagnostic specificity of these abnormalities has yet to be fully examined. Because recent evidence suggests that schizophrenia and bipolar disorder may share aspects of genetic etiology the present study was conducted to determine whether individuals with heightened genetic liability for each disorder manifested distinct neural abnormalities during auditory processing. Utilizing a dichotic listening paradigm, we assessed target tone discrimination and electrophysiological responses in schizophrenia patients, first-degree biological relatives of schizophrenia patients, bipolar disorder patients, first-degree biological relatives of bipolar patients and nonpsychiatric control participants. Schizophrenia patients and relatives of schizophrenia patients demonstrated reductions in an early neural response (i.e. N1) suggestive of deficient sensory registration of auditory stimuli. Bipolar patients and relatives of bipolar patients demonstrated no such abnormality. Both schizophrenia and bipolar patients failed to significantly augment N1 amplitude with attention. Schizophrenia patients also failed to show sensitivity of longer-latency neural processes (N2) to stimulus frequency suggesting a disorder specific deficit in stimulus classification. Only schizophrenia patients exhibited reduced target tone discrimination accuracy. Reduced N1 responses reflective of early auditory processing abnormalities are suggestive of a marker of genetic liability for schizophrenia and may serve as an endophenotype for the disorder.     

Relationship of birth cohort and early age at onset of illness in a bipolar disorder case registry

OBJECTIVE: Utilizing data from a previously characterized registry of subjects with bipolar illness, the authors examined age at onset of the first illness episode in cohorts of subjects born from 1900 through 1939 and from 1940 through 1959. METHOD: Demographic and clinical characteristics at the first full episode of bipolar disorder of subjects in a diagnostically validated voluntary bipolar disorder registry (N=1,218) were reviewed and subjected to statistical analyses. RESULTS: The median age at onset of the first episode of bipolar illness was lower by 4.5 years in subjects born during or after 1940 (median age=19 years), compared with subjects born before 1940 (median age=23.5 years). The proportion of subjects with bipolar disorder presenting with a prepubertal onset was significantly higher in the later birth-year cohort than in the earlier birth-year cohort. More than 50% of male and female subjects in both cohorts had a depressive episode as the first episode of bipolar illness. Subjects in each cohort who had a parent with major depression, bipolar disorder, or schizophrenia experienced their first episode nearly 4 to 5 years earlier than the other subjects in the cohort. CONCLUSIONS: Prospective epidemiological studies conducted with bipolar disorder subjects are needed to either affirm or refute these data on age at illness onset. If the results are affirmed, the early recognition of prepubertal bipolar disorder will be important, so that the condition can be treated with appropriate medications and medications that could potentially worsen the illness course can be avoided. Similarly, early recognition of bipolar illness is important, especially in women, to minimize use of antidepressant monotherapy for patients with bipolar illness. Among young people presenting with major depression as the first illness episode, a parental history of major depression, bipolar disorder, or psychosis may be a useful pointer to future bipolar disorder. Early recognition and appropriate treatment of bipolar illness may prevent the development of chronicity and serious functional impairment.     

ESPECTRA: Searching the Bipolar Spectrum in Eating Disorder patients

Background

Genome wide association studies reported two single nucleotide polymorphisms in ANK3 (rs9804190 and rs10994336) as independent genetic risk factors for bipolar disorder. Another SNP in ANK3 (rs10761482) was associated with schizophrenia in a large European sample. Within the debate on common susceptibility genes for schizophrenia and bipolar disorder, we tried to investigate common findings by analyzing association of ANK3 with schizophrenia, bipolar disorder and unipolar depression.

Methods

We genotyped three single nucleotide polymorphisms (SNPs) in ANK3 (rs9804190, rs10994336, and rs10761482) in a case-control sample of German descent including 920 patients with schizophrenia, 400 with bipolar affective disorder, 220 patients with unipolar depression according to ICD 10 and 480 healthy controls. Sample was further differentiated according to Leonhard's classification featuring disease entities with specific combination of bipolar and psychotic syndromes.

Results

We found no association of rs9804190 and rs10994336 with bipolar disorder, unipolar depression or schizophrenia. In contrast to previous findings rs10761482 was associated with bipolar disorder (p = 0.015) but not with schizophrenia or unipolar depression. We observed no association with disease entities according to Leonhard's classification.

Conclusion

Our results support a specific genetic contribution of ANK3 to bipolar disorder though we failed to replicate findings for schizophrenia. We cannot confirm ANK3 as a common risk factor for different diseases.