Multiple dimensions of familial psychopathology affect risk of mood disorder in children of bipolar parents

Risk factors for suicidality across psychosis vulnerability spectrum

BACKGROUND

Suicide is a leading cause of death in individuals with psychotic disorders. Risk factors for suicidality across the psychosis vulnerability spectrum are insufficiently known.

METHODS

For patients (n = 830), siblings (n = 664) and controls (n = 444), suicidality was assessed by the use of a clinical interview. Multilevel modelling was used to investigate risk factors of suicidality. Lastly, risk factor × familial risk interaction effects were examined.

RESULTS

Multivariable models revealed a significant relation between suicidality and depressive symptoms across all three groups, and childhood trauma in patients and siblings. The association between suicidality and psychotic-like experiences is more pronounced in siblings compared to controls.

CONCLUSION

Across the psychosis vulnerability spectrum, depressive symptoms and childhood trauma have been associated with suicidality. Clinicians should pay attention to suicidality in individuals at high familial risk for psychosis with psychotic-like experiences.

Familial load of psychiatric disorders and overall functioning in patients newly diagnosed with bipolar disorder and their unaffected first-degree relatives

BACKGROUND

Overall functioning is already impaired in patients newly diagnosed with bipolar disorder (BD) and, to a lesser degree, also in their unaffected first-degree relatives (UR). Further, aggregation of psychiatric disorders among the patients' first-degree relatives seems to be associated with higher illness burden and poorer prognosis. However, whether this aggregation of psychiatric disorders among first-degree relatives, the familial load (FL), impacts overall functioning in patients newly diagnosed with BD and their UR remains unresolved.

METHODS

In total, 388 patients newly diagnosed with BD, 144 of their UR and 201 healthy control individuals were included. Overall functioning was assessed using three different assessment methods: The interviewer based "Functioning Assessment Short Test" (FAST), the questionnaire "Work and Social Adjustment Scale" (WSAS) and six outcome measures covering the participants' socio-economic status (SES); educational achievement, employment, work ability, relationship, cohabitation and marital status. Familial load of psychiatric disorder was assessed using the "Family History Research Diagnostic Criteria" interview. Associations between FL and overall functioning in patients and UR were investigated categorically using logistic and continuously in linear regression models.

RESULTS

Contrasting with the hypotheses, the FL of psychiatric disorders was not associated with impaired overall functioning, neither in patients newly diagnosed with BD nor in their UR.

CONCLUSION

The findings indicate that impaired functioning in the early phase of BD is not associated with aggregation of psychiatric disorders among first-degree relatives. The observed functional impairment in patients newly diagnosed with BD seems driven by the personal impact of the disorder rather than the impact of having first-degree relatives with psychiatric disorders.

Familial risk for depressive and anxiety disorders: associations with genetic, clinical, and psychosocial vulnerabilities

BACKGROUND

In research and clinical practice, familial risk for depression and anxiety is often constructed as a simple Yes/No dichotomous family history (FH) indicator. However, this measure may not fully capture the liability to these conditions. This study investigated whether a continuous familial loading score (FLS), incorporating family- and disorder-specific characteristics (e.g. family size, prevalence of depression/anxiety), (i) is associated with a polygenic risk score (PRS) for major depression and with clinical/psychosocial vulnerabilities and (ii) still captures variation in clinical/psychosocial vulnerabilities after information on FH has been taken into account.

METHODS

Data came from 1425 participants with lifetime depression and/or anxiety from the Netherlands Study of Depression and Anxiety. The Family Tree Inventory was used to determine FLS/FH indicators for depression and/or anxiety.

RESULTS

Persons with higher FLS had higher PRS for major depression, more severe depression and anxiety symptoms, higher disease burden, younger age of onset, and more neuroticism, rumination, and childhood trauma. Among these variables, FH was not associated with PRS, severity of symptoms, and neuroticism. After regression out the effect of FH from the FLS, the resulting residualized measure of FLS was still associated with severity of symptoms of depression and anxiety, rumination, and childhood trauma.

CONCLUSIONS

Familial risk for depression and anxiety deserves clinical attention due to its associated genetic vulnerability and more unfavorable disease profile, and seems to be better captured by a continuous score that incorporates family- and disorder-specific characteristics than by a dichotomous FH measure.

More childhood onset bipolar disorder in the United States than Canada or Europe: Implications for treatment and prevention

Evidence of a high or increasing incidence of childhood onset bipolar disorder in the United States (US) has been viewed skeptically. Here we review evidence that childhood onsets of bipolar disorder are more common in the US than in Europe, treatment delays are longer, and illness course is more adverse and difficult. Epidemiological data and studies of offspring at high risk also support these findings. In our cohort of outpatients with bipolar disorder, two of the major vulnerability factors for early onset - genetics and environmental adversity in childhood - were also greater in the US than in Europe. An increased familial loading for multiple psychiatric disorders was apparent in 4 generations of the family members of the patients from the US, and that familial burden was linked to early onset bipolar disorder. Since both early onset and treatment delay are risk factors for a poor outcome in adulthood, new clinical, research, and public health initiatives are needed to begin to address and ameliorate this ongoing and potentially devastating clinical situation.

Increases in multiple psychiatric disorders in parents and grandparents of patients with bipolar disorder from the USA compared with The Netherlands and Germany

OBJECTIVE

We previously found that compared with Europe more parents of the USA patients were positive for a mood disorder, and that this was associated with early onset bipolar disorder. Here we examine family history of psychiatric illness in more detail across several generations.

METHODS

A total of 968 outpatients (average age 41) with bipolar disorder from four sites in the USA and three in the Netherlands and Germany (abbreviated as Europe) gave informed consent and provided detailed demographic and family history information on a patient questionnaire. Family history of psychiatric illness (bipolar disorder, unipolar depression, suicide attempt, alcohol abuse, substance abuse, and other illness) was collected for each parent, four grandparents, siblings, and children.

RESULTS

Parents of the probands with bipolar disorder from the USA compared with Europe had a significantly higher incidence of both unipolar and bipolar mood disorders, as well as each of the other psychiatric conditions listed above. With a few exceptions, this burden of psychiatric disorders was also significantly greater in the grandparents, siblings, and children of the USA versus European patients.

CONCLUSION

The increased complexity of psychiatric illness and its occurrence over several generations in the families of patients with bipolar disorder from the USA versus Europe could be contributing to the higher incidence of childhood onsets and greater virulence of illness in the USA compared with Europe. These data are convergent with others suggesting increased both genetic and environmental risk in the USA, but require replication in epidemiologically-derived populations with data based on interviews of the family members.

More pernicious course of bipolar disorder in the United States than in many European countries: implications for policy and treatment

BACKGROUND

There is some controversy but growing evidence that childhood onset bipolar disorder may be more prevalent and run a more difficult course in the United States than some European countries.

METHODS

We update and synthesize course of illness data from more than 960 outpatients with bipolar disorder (average age 40) from 4 sites in the U.S. and 3 sites in Netherlands and Germany. After giving informed consent, patients reported on parental history, childhood and lifetime stressors, comorbidities, and illness characteristics.

RESULTS

Almost all aspects of bipolar disorder were more adverse in patients from the US compared with Europe, including a significantly higher prevalence of: bipolar disorder in one parent and a mood disorder in both parents; childhood verbal, physical, or sexual abuse; stressors in the year prior to illness onset and the last episode; childhood onsets of bipolar illness; delay to first treatment; anxiety disorder, substance abuse, and medical comorbidity; mood episodes and rapid cycling; and nonresponse to prospective naturalistic treatment.

LIMITATIONS

Selection bias in the recruit of patients cannot be ruled out, but convergent data in the literature suggest that this does not account for the findings. Potential mechanisms for the early onset and more adverse course in the U.S. have not been adequately delineated and require further investigation.

CONCLUSIONS

The data suggest the need for earlier and more effective long-term treatment intervention in an attempt to ameliorate this adverse course and its associated heavy burden of psychiatric and medical morbidity.

A meta-analysis of the risk of major affective disorder in relatives of individuals affected by major depressive disorder or bipolar disorder

BACKGROUND

To conduct a meta-analysis to estimate the incidence of major depressive disorder (MDD) and bipolar disorder (BD) in first-degree relatives (FDRs) of probands affected by MDD or BD. The risk for MDD in FDR of BD probands and vice versa is also investigated.

METHODS

A systematic review of case-control and cohort studies, which were published between 1977 and 2012; reported relative risks (RR) or odd ratios (OR) or equivalent raw data; made an explicit distinction between MDD and BD; used operational diagnostic criteria; and reported systematic proband recruitment and ascertainment of relatives. Studies were obtained by electronic MEDLINE and EMBASE searches and hand-searching. Estimates were derived from pooled data using random effects methods.

RESULTS

Of an initial sample of 241 articles, 22 were eligible for inclusion. For FDRs of one proband with MDD compared to healthy control probands, estimates for MDD were OR=2.14 (95% CI 1.72-2.67), increasing to OR=3.23 (95% CI 2.11-4.94) for two MDD probands. For FDRs of one BD proband compared to healthy control probands, estimates for BD were OR=7.92 (95% CI 2.45-25.61), and OR=6.58 (95% CI 2.64-16.43) for FDRs of two BD probands.

CONCLUSIONS

These findings support previously published data indicating strong familiality for both MDD and BD. Data will be useful in providing individuals with a family history of MDD or BPD with tailored risk estimates.

A three generations nation-wide population study of family load estimates in bipolar disorder with different age at onset

OBJECTIVES

This nation-wide register-based study investigates how often bipolar disorder (BD) occurs in affected families compared to control families by estimating the family load as a random effect; this effect measures the degree of dependence among family members in relation to BD. Furthermore, the study addresses the impact of certain risk factors, namely, sex, age at onset of BD, degree of urbanization, year of birth, month of birth, and maternal and paternal age at birth.

METHOD

A total of N=1204 children and adolescent psychiatric cases born between 1950 and 1997 and registered in the Danish Central Psychiatric Register (DPCR) developed BD before the age of 58 years. N=3553 controls without any psychiatric diagnosis were matched for age, gender, and region of residence. Psychiatric diagnoses were also obtained on the relatives, e.g. parents, siblings, and offspring as a part of the Danish Three Generation Study (3GS). A family component was obtained by using different regression models.

RESULTS

Familial factors accounted for 20% of the variation in disease outcome when controlling for year and month of birth, sex, and degree of urbanization. Only female sex was associated with an increased hazard ratio of BD. Also having a mother, father or a sibling with the disorder was proven to be a significant risk factor. Furthermore, case relatives did not develop BD earlier than control relatives.

CONCLUSION

These findings based on a very large and representative dataset provide further and very solid evidence for the high family aggregation of BD.

Mental disorders in offspring of parents with bipolar and major depressive disorders

OBJECTIVES

There is limited information on the specificity of associations between parental bipolar disorder (BPD) and major depressive disorder (MDD) and the risk of psychopathology in offspring. The chief aim of the present study was to investigate the association between mood disorder subtypes in the two parents and mental disorders in the offspring.

METHODS

A total of 376 offspring (aged 6.0-17.9 years; mean=11.5years) of 72 patients with BPD (139 offspring), 56 patients with MDD (110 offspring), and 66 controls (127 offspring) participated in a family study conducted in two university hospital centers in Switzerland. Probands, offspring, and biological co-parents were interviewed by psychologists blind to proband diagnoses, using a semi-structured diagnostic interview.

RESULTS

Rates of mood and anxiety disorders were elevated among offspring of BPD probands (34.5% any mood; 42.5% any anxiety) and MDD probands (25.5% any mood; 44.6% any anxiety) as compared to those of controls (12.6% any mood; 22.8% any anxiety). Moreover, recurrent MDD was more frequent among offspring of BPD probands (7.9%) than those of controls (1.6%). Parental concordance for bipolar spectrum disorders was associated with a further elevation in the rates of mood disorders in offspring (64.3% both parents versus 27.2% one parent).

CONCLUSIONS

  These findings provide unique information on the broad manifestations of parental mood disorders in their offspring. The earlier onset and increased risk of recurrent MDD in the offspring of parents with BPD compared to those of controls suggests that the episodicity characterizing BPD may emerge in childhood and adolescence.

Concomitants of family histories of mood disorders and alcoholism in a clinical cohort of patients with bipolar I and II disorder

We diagnosed 191 secondary-care outpatients and inpatients with DSM-IV BD I or II. Sociodemographic and clinical characteristics, including axis I and II comorbidity, neuroticism, and prospective life-chart were evaluated at intake and at 6 and 18 months. The family history (FH) of mood disorders, alcoholism, or any major psychiatric disorders among first-degree relatives was investigated in a semistructured interview. Most (74%) patients had some positive FH; 55% of mood disorder, 36% of alcoholism. Positive FH was associated with psychiatric comorbidity and depressive course in the proband. Based on a multinomial logistic regression model, patients with an FH of mood disorder and alcoholism had an odds ratio of 4.8 (p = 0.001) for having an anxiety disorder. Overall, the first-degree relatives of patients with BD have multiple types of mental disorders, which correlate with bipolar patients' course of illness and psychiatric comorbidity. The strongest associations are between FH of mood disorders and presence of comorbid anxiety disorders.

Lifetime psychopathology among the offspring of Bipolar I parents

BACKGROUND

Recent studies have demonstrated high rates of psychopathology in the offspring of parents with bipolar disorder. The aim of this study was to identify psychiatric diagnoses in a sample of children of bipolar parents.

METHOD

This case series comprised 35 children and adolescents aged 6 to 17 years, with a mean age of 12.5 ± 2.9 years (20 males and 15 females), who had at least one parent with bipolar disorder type I. The subjects were assessed using the Schedule for Affective Disorders and Schizophrenia for School-Age Children - Present and Lifetime version (K-SADS-PL). Family psychiatric history and demographics were also evaluated.

RESULTS

Of the offspring studied, 71.4% had a lifetime diagnosis of at least one psychiatric disorder (28.6% with a mood disorder, 40% with a disruptive behavior disorder and 20% with an anxiety disorder). Pure mood disorders (11.4%) occurred less frequently than mood disorders comorbid with attention deficit hyperactivity disorder (17.1%). Psychopathology was commonly reported in second-degree relatives of the offspring of parents with bipolar disorder (71.4%).

CONCLUSIONS

Our results support previous findings of an increased risk for developing psychopathology, predominantly mood and disruptive disorders, in the offspring of bipolar individuals. Prospective studies with larger samples are needed to confirm and expand these results.

Clinical diagnoses in young offspring from eastern Québec multigenerational families densely affected by schizophrenia or bipolar disorder

OBJECTIVE

The follow-up since 1989 of a large sample of multigenerational families of eastern Québec that are densely affected by schizophrenia (SZ) or bipolar disorder (BP) has permitted to look at the rates of DSM diagnoses in the young offspring of a SZ parent (HRSZ) and of a BP parent (HRBP) who had an extremely loaded family history.

METHOD

The sample (average age of 17.5, SD 4.5) consisted of 54 high-risk offspring (HR) having one parent affected by a DSM-IV SZ or BP. The parents descended from 21 multigenerational families that constitute a quasi-total sample of such kindred in eastern Québec. The HRs were administered a lifetime best estimate DSM-IV diagnosis.

RESULTS

We observed that the rates, the diversity of diagnoses, the high comorbidity, the severity and the age of onset of the clinical diagnoses tended to be similar with those already reported in the offspring of affected parents with a low familial loading. Although the sample size was small, HRSZ and HRBP also tended to show similarities in their clinical status.

CONCLUSION

Overall, taking into account methodological limitations, the observation early in life of some shared characteristics among HRSZ and HRBP in terms of non-psychotic diagnosis may be congruent with the accumulating evidence that several phenotypic features are shared in adulthood by the two major psychoses.

Prediction of change in level of problem behavior among children of bipolar parents

OBJECTIVE

To determine the effects of familial loading, birth weight, and family problems on change in parent-reported problems across a 14-month period among children of bipolar parents.

METHOD

Emotional and behavioral problems in a sample of 140 offspring of bipolar parents and familial loading in first- and second-degree relatives were assessed at two measurements. Parents reported the birth weight of their offspring and completed a questionnaire on family problems. Multiple linear regression analyses were performed to assess associations of the three predictors with change in problem scores at follow-up.

RESULTS

Familial loading of unipolar disorder was a unique predictor for an increase in problem scores from the first to the second measurement with beta-coefficients ranging from 0.17 to 0.25. Birth weight and family problems were not associated with change in problem scores across the two measurements.

CONCLUSION

Familial loading of unipolar disorder predicted an increase in behavioral and emotional problems across the 14-month follow-up.

Pediatric bipolar disorder: a review of the past 10 years

OBJECTIVE

To review the literature of the past decade covering the epidemiology, clinical characteristics, assessment, longitudinal course, biological and psychosocial correlates, and treatment and prevention of pediatric bipolar disorder (BD).

METHOD

A computerized search for articles published during the past 10 years was made and selected studies are presented.

RESULTS

Pediatric BD is increasingly recognized, and there are several prevailing views on core features of this disorder. The incidence and prevalence of the disorder and the associated comorbidities vary according to study setting and criteria used. This disorder is highly recurrent and accompanied by substantial psychiatric and psychosocial morbidity. Familial studies, including "top down" (offspring of parents with BD) and "bottom up" (relatives of youths with BD) studies indicate that pediatric BD is aggregated in families with adult or later-onset BD and suggest the existence of genetic predisposition. Greater understanding of the risk factors for early onset BD and recognition of the phenomenology of prodromal symptoms offers hope for early identification and prevention. Neuroimaging studies indicate frontotemporal and frontostriatal pathology, but none of these findings seems to be disorder specific. Combination pharmacotherapies appear promising, and the field awaits further short- and long-term randomized, placebo-controlled trials. Preliminary studies of various psychotherapies, including psychoeducation strategies tailored specifically for BD in youths, look encouraging.

CONCLUSIONS

Considerable advances have been made in our knowledge of pediatric BD; however, differing viewpoints on the clinical presentation of BD in children are the rule. Phenomenological and longitudinal studies and biological validation using genetic, neurochemical, neurophysiological, and neuroimaging methods may strengthen our understanding of the phenocopy. Randomized, controlled treatment studies for the acute and maintenance treatment of BD disorder are warranted.

Stressful life events and onset of mood disorders in children of bipolar parents during 14-month follow-up

BACKGROUND

Although multiple studies have examined the association between stressful life events (SLEs) and the development of mood disorders, the exact nature of the association and the degree to which it is independent from familial loading (FL) and gender-specific are still not fully elucidated.

AIMS

To study the association between person-independent and -dependent SLEs and first onset or recurrence of a DSM-IV mood disorder episode (MDE) in offspring of bipolar parents. To examine interaction effects of SLEs with familial loading and gender.

METHOD

Offspring of bipolar parents (N=132) were assessed with the K-LEDS, the FHRDC and the K-SADS. Logistic regression analysis was used to examine main and interaction effects of various operationalizations of SLEs, familial loading and gender.

RESULTS

Dependent SLEs were more likely to occur before onset among the 13 offspring who had a MDE onset during the 14-month follow-up (39%) than in a comparable period among the 67 controls without any lifetime diagnosis (10%). Associations were slightly stronger for first onsets than for recurrences. The association between SLEs and MDE onset/recurrence was independent of socio-demographic characteristics and familial loading, but disappeared when adjusted for baseline anxious/depressive symptoms. Gender and familial loading did not modify the influence of any SLE measure on the development of mood disorders.

CONCLUSIONS

In this sample of bipolar offspring dependent stressful SLEs triggered the onset of MDEs, but this association disappeared after adjustment of prior anxious/depressive symptoms, indicating that the association between SLEs and MDE is probably a spurious association. No interaction was found between SLE and FL and gender. Prior anxious/depressive symptoms seem to increase the risk for both occurrence of dependent SLEs and MDE onset or recurrence.

LIMITATIONS

Limited statistical power due to small number of MDE onsets.

Impact of stressful life events, familial loading and their interaction on the onset of mood disorders: study in a high-risk cohort of adolescent offspring of parents with bipolar disorder

BACKGROUND

Stressful life events are established as risk factors for the onset of mood disorders, but few studies have investigated their impact on the development of mood disorders in adolescents.

AIMS

To study the effect of life events on the development of mood disorders in the offspring of parents with bipolar disorder, with respect to the possibility of a decay effect and modification by familial loading.

METHOD

In a high-risk cohort of 140 Dutch adolescent offspring of parents with bipolar disorder, we assessed life events, current and past DSM-IV diagnoses and familial loading. To explore their interaction and impact on mood disorder onset, we constructed four different models and used a multivariate survival analysis with time-dependent covariates.

RESULTS

The relationship between life events and mood disorder was described optimally with a model in which the effects of life events gradually decayed by 25% per year. The effect of life event load was not significantly stronger in the case of high familial loading.

CONCLUSIONS

Independent of familial loading, life events increase the liability to mood disorders in children of patients with bipolar disorder but the effects slowly diminish with time.