Predictors of later bipolar disorder in patients with subthreshold symptoms

Course of subthreshold manic symptoms and related risk factors in the general population: A three-year follow-up study

OBJECTIVES

Subthreshold manic symptoms (subM) are a risk factor for the onset and recurrence of bipolar disorder (BD). Individuals with subM may benefit from preventive interventions, however, their development is hampered by a lack of knowledge on subM prevalence and subsequent course. This study examines subM characteristics, course, and risk factors for an unfavourable course.

METHODS

In a Dutch representative, population-based sample aged 18-64 (N = 4618), we assessed subM, defined as the occurrence of manic core symptoms (elation/irritability), without meeting full DSM-IV criteria for BD I or II in the past 3 years. Comparison groups had either no manic symptoms (noM) or hypomania/mania in the context of BD (mBD) in the past 3 years. Furthermore, we differentiated a mild and moderate type of subM, based on the number of manic symptoms. A subsequent three-year course was assessed prospectively.

RESULTS

SubM had a three-year prevalence of 4.9%. Its prevalence, characteristics, and course were in between noM and mBD, and there were few differences between mild and moderate subM. Over the 3-year follow-up, 25.0% of individuals with subM had persistent subM and another 6.1% transitioned to mBD. Eleven significant risk factors for this unfavourable course were found. The most important were a history of depression/dysthymia (OR 3.75, p ≤ 0.001), living alone (OR 2.61, p ≤ 0.01) and elevated neuroticism score (OR 1.21, p ≤ 0.001).

CONCLUSIONS

This study supports the validity and clinical relevance of subM as a BD prodrome. It demonstrates that subM symptoms often persist or increase during follow-up and identifies 11 risk factors that are associated with an unfavourable course.

Risk factors for new-onset bipolar disorder in a community cohort: A five-year follow up study

The aim of this study was to assess the risk factors for new-onset Bipolar Disorder (BD) in a community sample of young adults. This is a prospective cohort study including a population-based sample of young adults aged between 18-24 years. The baseline took place from 2007 to 2009, and 1560 subjects were included. Five years after, 1244 individuals were re-evaluated (79.7% retention). Substance abuse/dependence was assessed using the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), and mental disorders were assessed using the Mini International Neuropsychiatric Interview 5.0 (MINI) at both waves. The cumulative incidence of BD in five years was 4.6%. There was no significant association between sociodemographic factors and BD incidence. Tobacco, cannabis, cocaine/crack, other substances abuse/dependence increased the relative risk for BD. Depressive, anxiety, post-traumatic stress disorders, and the suicide risk increased the relative risk to BD. Depressive episode was the strongest risk factor for BD, followed by other mental disorders and substance abuse/dependence in a probabilistic community sample of young adults. Preventive actions in mental health directed at the non-clinical population are needed for early detection and better management of BD.

Precursors of self-reported subclinical hypomania in adolescence: A longitudinal general population study

Symptoms of subclinical hypomania (SHM) are common in the general population of adolescents and young adults. SHM are most often transient yet might be risk markers of later bipolar disorder. The current study aimed to assess the clinical correlates of SHM at age 11 in the general population, examine the continuity of SHM from age 11-age 16 and explore the clinical precursors of age 16 SHM. As part of the Copenhagen Child Cohort 2000, 1,632 preadolescents participated in the examination of SHM and various clinical correlates at age 11, 893 were re-assessed for SHM at age 16 years. At age 11, SHM, psychotic experiences and depressive symptoms were assessed by semi-structured psychopathological interviews. Furthermore, the participants were diagnostically assessed by the Development and Well-Being Assessment and interviewed about sleep length. At age 16, SHM was assessed by self-report, using the Hypomania Checklist-32. Cannabis use occurring at age 15 or earlier was assessed at age 16. At age 11, SHM was associated with depressive disorders (Relative Risk [RR] = 2.96 [95% CI 1.26–6.96]), interview-based depressive symptoms (RR = 9.22 [5.93–14.34]), neurodevelopmental disorders (RR = 2.94 [1.66–5.20]), psychotic experiences (RR = 4.51 [2.90–7.01]) and insufficient sleep (RR = 2.10 [1.28–3.43]. In the longitudinal analyses, age 16 SHM was preceded by age 11 SHM (RR = 1.89 [1.02–3.49]), psychotic experiences (RR = 2.06, [1.28–3.33]), emotional disorders (RR = 1.77, [1.02–3.09]) and cannabis use (RR = 3.14, [1.93–5.10]), after mutual adjustment and adjustment for sex, and sociodemographic factors. In conclusion, age 11 SHM was statistically significantly associated with other types of psychopathology in cross-sectional analyses and showed some continuity with later self-reported SHM at age 16. Particularly early psychotic experiences and cannabis use stood out as independent precursors of self-reported SHM and might constitute important risk markers for the development of future SHM and bipolar disorder. An important potential caveat of the current study includes the self-report assessment of SHM.

An International Society of Bipolar Disorders task force report: Precursors and prodromes of bipolar disorder

OBJECTIVES

To clarify the clinical features preceding the onset of bipolar disorder (BD) has become a public health priority for the prevention of high morbidity and mortality. BD remains frequently under- or misdiagnosed, and under- or mistreated, often for years.

METHODS

We assessed the predictive value of precursors and prodromes of BD. We assessed precursors of first-lifetime manic or hypomanic episodes with/without mixed features in retrospective and prospective studies. The task force evaluated and summarized separately assessments of familial risk, premorbid personality traits, retrospective, and prospective studies.

RESULTS

Cyclothymic features, a family history of BD, retrospectively reported attenuated manic symptoms, prospectively identified subthreshold symptoms of hypomania, recurrence of depression, panic anxiety and psychotic features, have been identified as clinical precursors of BD. The prodromal symptoms like [hypo]mania often appears to be long enough to encourage early identification and timely intervention.

CONCLUSIONS

The predictive value of any risk factor identified remains largely unknown. Prospective controlled studies are urgently needed for prevention and effective treatment.

Anxiety disorders anticipate the diagnosis of bipolar disorder in comorbid patients: Findings from an Italian tertiary clinic

BACKGROUND

Studies indicate bipolar disorder (BD) syndromal symptoms are commonly preceded by sub-syndromal BD symptoms, dysregulated sleep, irritability, and anxiety. We aimed to evaluate prevalence and clinical correlates of anxiety disorders (ADs) at BD onset in outpatients with versus without at least one AD at BD onset.

METHODS

246 bipolar spectrum outpatients, according to the text revision of the fourth edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM- IV-TR), attending Sacco University Hospital in Milan, were recruited and their onset and clinical features assessed retrospectively. Patients were stratified into those with versus without an AD at BD onset (w/A and wo/A), according to a semi-structured clinical interview to provide diagnoses according to (DSM- IV-TR).

RESULTS

29% of patients reported being w/A, among whom Panic Disorder (PD, in 55.6%) was the most frequent AD, and first AD occurred approximately 4 years before BD diagnosis. Patients w/A versus wo/A had higher (p < 0.05) rates of BDII and first mood episode being depression versus elevation (mania/hypomania), and lifetime rates of separation anxiety disorder, substance poly-abuse and benzodiazepine abuse. In contrast, patients wo/A had higher lifetime rates of alcohol and illicit drug use.

CONCLUSION

In this naturalistic sample, ADs, in particular PD, preceded BD in almost 1/3 of BD outpatients, and had distinctive clinical correlates. Further investigation into relationships between BD and AD at onset may enhance early BD diagnosis and treatment.

Clinical and Environmental Risk Factors for Bipolar Disorder: Review of Prospective Studies

After participating in this activity, learners should be better able to:• Evaluate factors that have been identified in prospective studies as predicting the onset of bipolar disorder ABSTRACT: The prodromal phase of bipolar disorder (BD) remains incompletely characterized, limiting early detection of BD and delaying interventions that might limit future morbidity and disability. Retrospective and family-risk studies have consistently found evidence of prodromal psychopathology in subjects later diagnosed with BD. Here, we review prospective studies of clinical risk factors and exposures identified before diagnosis of BD: our findings are consistent with those from retrospective and family-risk studies. Affective psychopathology often precedes diagnosis to suggest a homotypic trajectory in developing BD. Early non-affective (heterotypic) psychopathological disturbances, including anxiety and disruptive behavior disorders, as well as environmental factors and exposures, have been found in prospective studies to increase the risk of BD, but tend to lack specificity in predicting BD. Findings from prospective studies are encouragingly similar to those of retrospective and family-risk studies.

Cluster analysis with MOODS-SR illustrates a potential bipolar disorder risk phenotype in young adults with remitted major depressive disorder

OBJECTIVES

Delays in the diagnosis and detection of bipolar disorder can lead to adverse consequences, including improper treatment and increased suicide risk. The Mood Spectrum Self-Report Measure (MOODS-SR) was designed to capture the full spectrum of lifetime mood symptomology with factor scores for depression and mania symptom constellations. The utility of the MOODS-SR as a tool to investigate homogeneous subgroups was examined, with particular focus on a possible bipolar risk subgroup. Moreover, potential patterns of differences in MOODS-SR subtypes were probed using cognitive vulnerabilities, neuropsychological functioning, and ventral striatum connectivity.

METHODS

K-mean cluster analysis based on factor scores of MOODS-SR was used to determine homogeneous subgroupings within a healthy and remitted depressed young adult sample (N = 86). Between-group comparisons (based on cluster subgroupings) were conducted on measures of cognitive vulnerabilities, neuropsychological functioning, and ventral striatum rs-fMRI connectivity.

RESULTS

Three groups of participants were identified: one with minimal symptomology, one with moderate primarily depressive symptomology, and one with more severe manic and depressive symptomology. Differences in impulsivity, neuroticism, conscientiousness, facial perception accuracy, and rs-fMRI connectivity exist between moderate and severe groups.

CONCLUSIONS

Within a sample of people with and without depression histories, a severe subgroup was identified with potentially increased risk of developing bipolar disorder through use of the MOODS-SR. This small subgroup had higher levels of lifetime depression and mania symptoms. Additionally, differences in traits, affective processing, and connectivity exist between those with a more prototypic unipolar subgrouping and those with potential risk for developing bipolar disorder.

Measuring racing thoughts in healthy individuals: The Racing and Crowded Thoughts Questionnaire (RCTQ)

Racing thoughts refer to an acceleration and overproduction of thoughts, which have been associated with manic and mixed episodes. Phenomenology distinguishes 'crowded' from 'racing' thoughts, associated with mixed depression and mania, respectively. Recent data suggest racing thoughts might also be present in healthy individuals with sub-affective traits and symptoms. We investigated this assumption, with a 34-item self-rating scale, the Racing and Crowded Thoughts Questionnaire (RCTQ), and evaluated its reliability, factor structure, and concurrent validity. 197 healthy individuals completed the RCTQ, the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego - autoquestionnaire (TEMPS-A), the Beck Depression Inventory (BDI), the Altman Self-Rating Mania scale (ASRM), and the Ruminative Response Scale (RRS). Exploratory factor analysis yielded a three-factor solution, labeled 'thought overactivation', 'burden of thought overactivation', and 'thought overexcitability'. Internal consistency of each of the three subscales of the RCTQ was excellent. The TEMPS-A cyclothymia score was associated with the three factors, suggesting good concurrent validity. The 'thought activation' subscale was selectively associated with current elated mood and included items conveying both the notion of increased amount and velocity of thoughts, whereas the 'burden of thought overactivation' subscale was associated with current low mood. The 'thought overexcitability' subscale included items conveying the notion of distractibility, and was associated with both elated and low mood. Rumination was not a significant predictor of RCTQ subscores. These results suggest that the RCTQ has good psychometric properties. Racing and crowded thoughts, as measured by the RCTQ, are a multi-faceted phenomenon, distinct from rumination, and particularly associated with mood instability even in its milder forms.

Do some anxiety disorders belong to the prodrome of bipolar disorder? A clinical study combining retrospective and prospective methods to analyse the relationship between anxiety disorder and bipolar disorder from the perspective of biorhythms

BACKGROUND

In clinical practice, some patients diagnosed with anxiety disorder (AD) may develop bipolar disorder (BD) many years later, and some cases of AD may be cured by the use of mood stabilizers. However, the relationship between AD and BD should be explored further.

METHOD

To track how many cases of AD turned to BD and to discover the differences between them, we recruited 48 patients diagnosed with BD, who were assigned to the BD group for the retrospective analysis, and we also recruited 186 patients diagnosed with AD at enrolment; this latter group was asked to complete follow-up surveys conducted 3 months, 6 months, 12 months and 18 months after the primary stage of the study. We defined another two groups according to the usage of mood stabilizers, the rates of reduction in scores on the Hamilton Anxiety Scale and Yale-Brown Obsessive Compulsive Scale, and the changes in Clinical Global Impression scores at different follow-up times: the anxiety group and the atypical BD group (who used mood stabilizers to treat AD). All subjects also completed the NEO Five-Factor Inventory and supplied blood samples to be tested for several endocrine indices (TSH, T3, FT3, T4, FT4, ACTH,PTC) and inflammatory cytokines (IL-6, IL-8, IL-10, TNF-α, CRP) at enrolment.

RESULTS

In total, 14 subjects developed BD by the end of the study. One hundred eleven subjects were included in the anxiety group. Sixty-three subjects were assigned to the atypical BD group, and they had similar features to the 48 subjects in the BD group in terms of personality traits, abnormality rates of endocrine indices and levels of inflammatory cytokines. From the anxiety group to the atypical BD group and then the BD group, the age of first onset gradually decreased, while the frequency of onset and the score of suicidal ideation gradually increased. Furthermore, the atypical BD group showed markedly higher levels of TSH, IL-6, TNF-α and CRP than the other two groups.

CONCLUSIONS

Some ADs with unique features might belong to the prodromal stage or the atypical presentation of BD, and recognizing these ADs early will economize many medical resources.

A 10-year evaluation on adolescents with anxiety disorders: are they at risk of bipolarity?

OBJECTIVE

Anxiety disorders are the most frequent disorders comorbid with bipolar disorder (BD) often preceding the BD onset. The presence of comorbid anxiety in patients diagnosed with BD is associated with worsening of their BD symptoms, increased risky behaviour, decreased response to pharmacological treatment and deterioration in their quality of life and global functioning. The aim of this study was to investigate if anxiety disorders in adolescence could be considered as predictors of BD.

METHODS

Adolescents with a primary anxiety disorder were recruited consecutively from the Mood and Anxiety Disorders Unit, Department of Neuroscience, University of Turin. Subjects were evaluated for Axis I psychiatric disorders, family history and global functioning, and followed up on average 10 years later.

RESULTS

A total of 29 patients (59.2%) were male and the mean age at the onset of anxiety disorder was 16.3 (±0.8). Ten years following recruitment, 11 (22.4%) patients fulfilled the criteria for BD. Of them, 10 (90.9%) had a family history of BD and four (36.4%) presented a comorbid substance use disorder.

CONCLUSIONS

Our study shows that both family history of BD and substance use disorder, in adolescent patients with a primary anxiety disorder, should be considered as potential predictors of BD onset.

Is There a Bipolar Prodrome Among Children and Adolescents?

Bipolar disorder in youth substantially impairs behavior, family, and social functioning and interferes with developmental course. There is increasing interest in defining a bipolar prodrome similar to that reported in early-onset psychosis that will allow for earlier intervention and reduction in overall morbidity and mortality. Several lines of research have addressed this important issue including studies of offspring of bipolar parents, high-risk cohorts, and longitudinal follow-up of subjects with major depressive disorder (MDD), ADHD, and bipolar spectrum disorder. The development and validation of bipolar prodrome rating scales also shows promise. Recent attempts to intervene at earlier stages of bipolar disorder have led to some positive outcomes. However, a controversy remains concerning the identification and management of the earliest symptoms. Further research is needed to fully validate a bipolar prodrome and to determine the optimal course of action at various stages of illness.

Inflammation, neurotrophism and oxidative stress and childhood psychopathology in a large community sample

OBJECTIVE

To investigate the association between peripheral biomarkers and child psychopathology in a large community sample.

METHOD

A total of 625 aged 6- to 13-year old subjects were recruited from a community school-based study. Psychopathology was assessed using the Child Behaviour Checklist (CBCL). Psychiatric diagnosis was evaluated using the Development and Well-Being Assessment. The following biomarkers were examined in peripheral blood: brain-derived neurotrophic factor, cytokines (IL-2, IL-4, IL-6, IL-10, IL-17, IFN-g, and TNF-α), chemokines (eotaxin/CCL11, IP-10, MCP-1), cytokine receptors (sTNFR1 and sTNFR2), and the oxidative stress marker TBARS.

RESULTS

We found significant associations between sTNFR2, eotaxin/CCL11 and CBCL total score, as well as with specific dimensions of psychopathology. There were different patterns of association between these biomarkers and psychological and behavioural symptoms in children with and without a mental disorder. TBARS, IL-6 and MCP-1 were more specific to some clusters of symptoms in children with a psychiatric diagnosis.

CONCLUSION

Our data support the potential use of biomarkers, especially those involved in immune-inflammatory pathways, in investigating neurodevelopmental psychopathology. Their association with different dimensions of symptoms might be of useful when analyzing illness severity and clusters of symptoms within specific disorders.

Features preceding diagnosis of bipolar versus major depressive disorders

BACKGROUND

Better and earlier predictive differentiation of bipolar (BD) vs. unipolar major depressive disorder (UD) diagnoses should improve long-term clinical planning.

METHODS

We reviewed randomly selected clinical records of 334 adults diagnosed with DSM-IV-TR BD-I (n=109), BD-II (n=106), and UD (n=119) and compared features preceding major affective episodes or diagnoses, using bivariate, multivariate, and Bayesian methods.

RESULTS

We identified antecedents selectively associated with later BD vs. UD in 52.6% vs. 31.1% of subjects in childhood, starting at age 7.4 years, and 60.0% vs. 32.8% in adolescence, with far more features in BD than UD cases (10.3 vs. 4.64/100 person-years; p<0.001). In multivariate modeling, BD-selective factors were: younger at first clinical event > male sex > family BD-history > cyclothymic or hyperthymic temperament > antecedents/person-year. Nonaffective (anxiety, eating, or substance-use) disorders preceded BD vs. UD in 41.4% vs. 28.6% of subjects (p=0.02). By ROC analysis, differential prediction of BD vs. UD was optimal with any ≥ 3 factors/person.

LIMITATIONS

The validity and timing of antecedent events and factors identified retrospectively from clinical records could not be verified independently, but information was recorded systematically and consistently by a single mood-disorder expert prior to diagnosis, and extracted by two independent observers.

COMMENT

Early clinical features distinguished later BD from UD, often by years. Such prediction should improve treatment-planning and limit risk of mood-switching.

Clinical risk factors for bipolar disorders: a systematic review of prospective studies

BACKGROUND

Early phases and suspected precursor states of bipolar disorder are not well characterized. We evaluate the prevalence, duration, clinical features and predictive value of non-affective psychopathology as clinical risk factors for bipolar disorder in prospective studies.

METHODS

We screened PubMed, CINAHL, PsycINFO, Embase, SCOPUS, and ISI-Web of Science databases from inception up to January 31, 2014, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and searched: bipolar disorder AND [antecedent⁎ OR predict⁎ OR prodrom⁎ OR prospect⁎ OR risk⁎] AND [diagnosis OR development]. We included only English language reports on prospective, longitudinal studies with two structured clinical assessments (intake and follow-up); no DSM intake diagnosis of bipolar-I or -II; diagnostic outcome was bipolar-I or -II. Details of study design, risk factors, and predictive value were tabulated.

RESULTS

We found 16 published reports meeting selection criteria, with varying study design. Despite heterogeneity in methods, findings across studies were consistent. Clinical risk factors of bipolar disorder were early-onset panic attacks and disorder, separation anxiety and generalized anxiety disorders, conduct symptoms and disorder, ADHD, impulsivity and criminal behavior.

LIMITATIONS

Since risk factors identified in some prospective studies are predictive of other conditions besides bipolar disorder, these preliminary findings require replication, and their sensitivity, specificity and predictive value need to be assessed.

CONCLUSIONS

Clinical risk factors for bipolar disorder typically arise years prior to syndromal onset, include anxiety and behavioral disorders with unclear sensitivity and specificity. Prospectively identified clinical risk factors for bipolar disorder are consistent with retrospective and family-risk studies. Combining clinical risk factors with precursors and family-risk may improve early identification and timely and appropriate treatment of bipolar disorder.

Is the combination of a mood stabilizer plus an antipsychotic more effective than mono-therapies in long-term treatment of bipolar disorder? A systematic review

BACKGROUND

Bipolar Disorder (BD) long-term treatment is aimed to prevent relapses associated with worsening cognitive impairment and chronicity. Available mood stabilizers, including lithium, fail to prevent relapses in about 40% of bipolar patients. Purpose of the present paper is to review the available data about the efficacy and tolerability of mood stabilizer plus antipsychotic combined treatments.

METHOD

A research in the main database sources has been conducted to obtain an overview about the efficacy and tolerability of the combination of a mood stabilizer plus an antipsychotic in the long-term treatment of BD. Papers with different methodologies but having relapse prevention as main outcome have been included.

RESULTS

Despite the heterogeneity of studies in terms of methodology, almost all papers reported a major efficacy of combined treatments respect to mood stabilizer mono-therapies but lower tolerability. The antipsychotic that presents more evidence of efficacy in combination with mood stabilizers is quetiapine.

DISCUSSION

Combined treatments can be a valid option to improve relapse prevention in BD. However, the higher risk for side effects has to be taken into account and specific combinations should be preferred according to patients' medical comorbidity.