The comorbidity of ADHD and bipolar disorder: any less confusion?

Comorbid attention-deficit hyperactivity disorder and bipolar disorder

The rate of comorbid attention-deficit hyperactivity disorder and bipolar disorder far exceeds chance if the two are independent conditions. Explanations for such a high comorbid prevalence and management implications are considered.

Focus on function: Therapies for adults with attention-deficit/hyperactivity disorder

ABSTRACT

Attention-deficit/hyperactivity disorder (ADHD) is a common disorder affecting people of all ages, and is characterized by inattention, hyperactivity, and impulsivity. Adults frequently have less hyperactivity or impulsivity but struggle more with inattentiveness and restlessness. Adults also may have comorbid psychiatric conditions and substance use issues that can make ADHD challenging to detect and treat. If left untreated, ADHD may harm the patient's quality of life. This article examines therapies for treating adults with ADHD.

Risks of major mental disorders after parental death in children, adolescents, and young adults and the role of premorbid mental comorbidities: a population-based cohort study

Previous studies have shown an association between early parental death and the risk of subsequent major mental disorders (MMDs) among the bereaved children and adolescents; however, it is unclear whether this risk exists in young adults and in individuals with premorbid mental comorbidities. We aimed to explore differences between children, adolescents, and young adults in the risk of MMDs after parental death. We analyzed data from the Taiwan National Health Research Database. The index cohort was offspring (divided into four groups: aged < 6, 6-11, 12-17, and 18-29 years) whose parents had died. The control cohort was demographically matched offspring whose parents were still alive. Cox regression with adjustments for demographics was used to estimate the risk of subsequent MMDs between the index and control cohorts, including schizophrenia, bipolar disorder, and depressive disorder. We included 202,837 cases and 2,028,370 matched controls. As with the bereaved children and adolescents, the bereaved young adults had a significantly higher risk of schizophrenia (hazard ratio with 95% confidence interval: 5.63; 5.01-6.33), bipolar disorder (3.37; 2.96-3.84), and depressive disorder (2.78; 2.68-2.90) than the control cohort. The risk of MMDs was similar for maternal death and paternal death. Among premorbid mental comorbidities, bereaved individuals with premorbid substance use disorder were associated with the highest risk of schizophrenia (10.43; 8.57-12.71), bipolar disorder (12.93; 10.59-15.79), and depressive disorder (10.97; 10.22-11.78). Healthcare workers should be aware that young adults and individuals with premorbid mental comorbidities are at a higher risk of subsequent MMDs than those without premorbid mental comorbidities after parental death.

Characterization of affective lability across subgroups of psychosis spectrum disorders

BACKGROUND

Affective lability is elevated and associated with increased clinical burden in psychosis spectrum disorders. The extent to which the level, structure and dispersion of affective lability varies between the specific disorders included in the psychosis spectrum is however unclear. To have potential value as a treatment target, further characterization of affective lability in these populations is necessary. The main aim of our study was to investigate differences in the architecture of affective lability in different psychosis spectrum disorders, and if putative differences remained when we controlled for current symptom status.

METHODS

Affective lability was measured with The Affective Lability Scale Short Form (ALS-SF) in participants with schizophrenia (SZ, n = 76), bipolar I disorder (BD-I, n = 105), bipolar II disorder (BD-II, n = 68) and a mixed psychosis-affective group (MP, n = 48). Multiple analyses of covariance were conducted to compare the ALS-SF total and subdimension scores of the diagnostic groups, correcting for current psychotic, affective and anxiety symptoms, substance use and sex. Double generalized linear models were performed to compare the dispersion of affective lability in the different groups.

RESULTS

Overall group differences in affective lability remained significant after adjusting for covariates (p = .001). BD-II had higher affective lability compared to SZ and BD-I (p = .004), with no significant differences between SZ and BD-I. There were no significant differences in the contributions of ALS-SF dimensions to the total affective lability or in dispersion of affective lability between the groups.

CONCLUSIONS

This study provides the construct of affective lability in psychosis spectrum disorders with more granular details that may have implications for research and clinical care. It demonstrates that despite overlap in core symptom profiles, BD-I is more similar to SZ than it is to BD-II concerning affective lability and the BD groups should consequently be studied apart. Further, affective lability appears to be characterized by fluctuations between depressive- and other affective states across different psychosis spectrum disorders, indicating that affective lability may be related to internalizing problems in these disorders. Finally, although the level varies between groups, affective lability is evenly spread and not driven by extremes across psychosis spectrum disorders and should be assessed irrespective of diagnosis.

Pre-pubertal bipolar disorder: origins and current status of the controversy

BACKGROUND

Evidence from epidemiological, clinical and high-risk studies has established that the peak period of risk for onset of bipolar disorder spans late adolescence and early adulthood. However, the proposal of the existence of a pre-pubertal form of bipolar disorder manifesting in early childhood created substantial debate. In this narrative review, the literature and contributing factors pertaining to the controversy surrounding the proposed pre-pubertal bipolar disorder subtype are discussed. The resolution of the debate and lessons learned are highlighted.

MAIN BODY

In the mid 1990s US researchers proposed that chronic irritability and explosive temper in pre-pubertal children with pre-existing ADHD and/or other learning and developmental disorders might represent a variant of mania. A number of factors contributed to this proposal including severely ill children with no diagnostic home given changes in the ADHD DSM diagnostic criteria and over-reliance on symptoms and structured interviews rather than on a clinical assessment incorporating developmental history, social context and clinical course. Prospective studies of children at high familial risk did not support the proposed pre-pubertal bipolar phenotype; but rather provided convergent evidence that bipolar disorder onset in adolescence and early adulthood not uncommonly preceded by sleep and internalizing symptoms and most often debuting as depression in adolescence (after puberty). Epidemiological studies of population and hospital discharge data provided evidence that the pre-pubertal bipolar phenotype was largely a US driven phenomenon.

CONCLUSIONS

Psychiatric diagnosis is particularly challenging given the current lack of objective biomarkers. However, validity and utility of clinical diagnoses can be strengthened if all available predictive information is used to formulate a diagnosis. As in other areas of medicine, critical information required to make a valid diagnosis includes developmental history, clinical course, family history and treatment response-weighed against the known trajectories of classical disorders. Moreover, given that psychiatric disorders are in evolution over childhood and adolescence and symptoms, in of themselves, are often non-specific, a thorough clinical assessment incorporating collateral history and psychosocial context is paramount. Such an approach might have avoided or at least brought a more timely resolution to the debate on pre-pubertal mania.

A systematic review of the frequency and severity of manic symptoms reported in studies that compare phenomenology across children, adolescents and adults with bipolar disorders

BACKGROUND

In the last two decades, there has been a significant increase in the diagnosis of Bipolar Disorder (BD) in children. The notion of prepubertal onsets of BD is not without controversy, with researchers debating whether paediatric cases have a distinct symptom profile or follow a different illness trajectory from other forms of BD. The latter issue is difficult to address without long-term prospective follow-up studies. However, in the interim, it is useful to consider the phenomenology observed in groups of cases with different ages of onset and particularly to compare manic symptoms in children diagnosed with BD compared to cases presenting with BD in adolescence and adulthood. This review systematically explores the phenomenology of manic or hypomanic episodes in groups defined by age at onset of BD (children, adolescents and adults; or combined age groups e.g. children and adolescents versus adults).

METHODS

Literature reviews of PubMed and Scopus were conducted to identify publications which directly compared the frequency or severity of manic symptoms in individuals with BD presenting with a first episode of mania in childhood, adolescence or adulthood.

RESULTS

Of 304 studies identified, 55 texts warranted detailed review, but only nine studies met eligibility criteria for inclusion. Comparison of manic symptoms across age groups suggested that irritability is a key feature of BD with an onset in childhood, activity is the most prominent in adolescent-onset BD and pressure of speech is more characteristic of adult-onset BD. However, none of the eligible studies made a direct comparison of phenomenology in children versus adults. Assessment procedures varied in quality and undermined the reliability of cross-study comparisons. Other limitations were: the scarcity of comparative studies, the geographic bias (most studies originated in the USA), the failure to fully consider the impact of psychiatric comorbidities on recorded symptoms and methodological heterogeneity.

CONCLUSIONS

Despite frequent discussion of similarities and differences in phenomenology of mania presenting in different age groups, systematic research is lacking and studies are still required to reliably establish whether the frequency and severity of manic symptoms varies. Such information has implications for clinical practice and the classification of mental disorders.

Bipolar Disorder in Children With ADHD: A Clinical Sample Study

OBJECTIVE

To explore the impact of early-onset bipolar disorder (pediatric bipolar disorder [PBD]) on ADHD.

METHOD

We compared ADHD symptom severity, ADHD subtype distribution, and rates of comorbid and familial psychiatric disorders between 49 ADHD children with comorbid PBD and 320 ADHD children without PBD.

RESULTS

Children with ADHD and PBD showed higher scores in the Hyperactive and Inattentive subscales of the ADHD Rating Scale, than children with ADHD alone. The frequency of combined subtype was significantly higher in ADHD children with PBD, than in those with ADHD alone. ADHD children with PBD showed a higher rate of familial psychiatric disorders than ADHD children without PBD. The rate of conduct disorder was significantly greater in children with PBD and ADHD compared with children with ADHD alone.

CONCLUSION

ADHD along with PBD presents with several characteristics that distinguish it from ADHD alone, suggesting that these may be distinct disorders.

Decreasing Rates of Pediatric Bipolar Within an Outpatient Practice

PROBLEM

Pediatric bipolar disorder (PBD) prevalence is estimated to be 1-3%. Nationally and internationally, rates of PBD have increased by over 400%. However, in Iowa and at one psychiatric clinic in Iowa, from 2008-2013, there was a decrease in PBD diagnosis of 33 and 51.2% respectively. This study examined the diagnosing practices of PBD by local providers in one outpatient mental health center.

METHOD

Parents completed a screening packet to differentiate between PBD and attention deficit hyperactivity disorder (ADHD) using three tools: Child Mania Rating Scale (CMRS), Child Behavior Checklist-Mania Scale (CBCL-MS), and the NICHQ Vanderbilt. Symptom agreement analysis between the screeners and the provider's clinical diagnoses was performed using ANOVA and Tukey HSD posthoc analysis.

FINDINGS

A 19.6% of the participants were positive for PBD on the CMRS and 55.9% were positive on the CBCL-MS.  A total of 36.60% were positive for ADHD on the Vanderbilt.  The screening data compared to the provider's clinical diagnosis showed no diagnostic agreement for PBD (p < .05). Providers' rates of diagnosing PBD did not match the rate of PBD symptoms identified by the screeners.

CONCLUSION

Further evidence to determine the criteria and use of current screening measures for PBD is needed to guide practice for distinguishing PBD from related disorders.

Attention-deficit hyperactivity disorder, its pharmacotherapy, and the risk of developing bipolar disorder: A nationwide population-based study in Taiwan

In this study, we aimed to evaluate the relationship between attention-deficit/hyperactivity disorder (ADHD) during childhood and subsequent diagnoses of bipolar disorder (BD), as well as to determine whether the pharmacotherapy for ADHD (methylphenidate and atomoxetine) influence the risks of developing BD. A nationwide cohort of patients newly diagnosed with ADHD (n = 144,920) and age- and gender-matching controls (n = 144,920) were found in Taiwan's National Health Insurance database from January 2000 to December 2011. Both patients and controls were observed until December 31, 2011. To determine the effect that the duration of methylphenidate and atomoxetine exposure had on BD, the difference in the risk of developing BD was compared among non-users, short-term users (≤ 365 days), and long-term users (>365 days). In comparison to the control group, the ADHD group showed a significantly increased risk of developing BD (ADHD: 2.1% vs.

CONTROLS

0.4%; aHR: 7.85, 95% CI: 7.09-8.70), and had a younger mean age at the time of first diagnosis (ADHD: 12.0 years vs.

CONTROLS

18.8 years). Compared to ADHD patients that had never taken methylphenidate, patients with long-term use of methylphenidate were less likely to be diagnosed with BD (aOR: 0.72, 95% CI: 0.65-0.80). However, the duration of exposure to atomoxetine did not have a significant relationship to a BD diagnosis. The results suggested that a previous diagnosis of ADHD was a powerful indicator of BD, particularly juvenile-onset BD. Nevertheless, the exact mechanisms of the relationships among ADHD, its pharmacotherapy, and BD require further clarification in the future.

Investigating the underlying mechanisms of aberrant behaviors in bipolar disorder from patients to models: Rodent and human studies

Psychiatric patients with bipolar disorder suffer from states of depression and mania, during which a variety of symptoms are present. Current treatments are limited and neurocognitive deficits in particular often remain untreated. Targeted therapies based on the biological mechanisms of bipolar disorder could fill this gap and benefit patients and their families. Developing targeted therapies would benefit from appropriate animal models which are challenging to establish, but remain a vital tool. In this review, we summarize approaches to create a valid model relevant to bipolar disorder. We focus on studies that use translational tests of multivariate exploratory behavior, sensorimotor gating, decision-making under risk, and attentional functioning to discover profiles that are consistent between patients and rodent models. Using this battery of translational tests, similar behavior profiles in bipolar mania patients and mice with reduced dopamine transporter activity have been identified. Future investigations should combine other animal models that are biologically relevant to the neuropsychiatric disorder with translational behavioral assessment as outlined here. This methodology can be utilized to develop novel targeted therapies that relieve symptoms for more patients without common side effects caused by current treatments.

Bipolar disorder and ADHD: comorbidity and diagnostic distinctions

Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) are neurodevelopmental disorders with onset in childhood and early adolescence, and common persistence in adulthood. Both disorders are often undiagnosed, misdiagnosed, and sometimes over diagnosed, leading to high rates of morbidity and disability. The differentiation of these conditions is based on their clinical features, comorbidity, psychiatric family history course of illness, and response to treatment. We review recent relevant findings and highlight epidemiological, clinical, family history, course, and treatment-response differences that can aid the differential diagnosis of these conditions in an outpatient pediatric setting.

Comorbidity in pediatric bipolar disorder: prevalence, clinical impact, etiology and treatment

BACKGROUND

Research on pediatric bipolar disorder (PBD) is providing a plethora of empirical findings regarding its comorbidity. We addressed this question through a systematic review concerning the prevalence, clinical impact, etiology and treatment of main comorbid disorders involved.

METHOD

A comprehensive database search was performed from 1990 to August 2014. Overall, 167 studies fulfilled the inclusion criteria.

RESULTS

Bipolar youth tend to suffer from comorbid disorders, with highest weighted mean prevalence rate arising from anxiety disorders (54%), followed by attention deficit hyperactivity disorder (ADHD) (48%), disruptive behavior disorders (31%), and substance use disorders (SUD) (31%). Furthermore, evidence indicates that ADHD and anxiety disorders negatively affect the symptomatology, neurocognitive profile, clinical course and the global functioning of PBD. Likewise, several theories have been posited to explain comorbidity rates in PBD, specifically common risk factors, one disorder being a risk factor for the other and nosological artefacts. Lastly, randomized controlled trials highlight a stronger therapeutic response to stimulants and atomoxetine (vs. placebo) as adjunctive interventions for comorbid ADHD symptoms. In addition, research focused on the treatment of other comorbid disorders postulates some benefits from mood stabilizers and/or SGA.

LIMITATIONS

Epidemiologic follow-up studies are needed to avoid the risk of nosological artefacts. Likewise, more research is needed on pervasive developmental disorders and anxiety disorders, especially regarding their etiology and treatment.

CONCLUSIONS

Psychiatric comorbidity is highly prevalent and is associated with a deleterious clinical effect on pediatric bipolarity. Different etiological pathways may explain the presence of these comorbid disorders among bipolar youth. Standardized treatments are providing ongoing data regarding their effectiveness for these comorbidities among bipolar youth.

How to Understand Divergent Views on Bipolar Disorder in Youth

There are two divergent viewpoints on the phenomenology and outcome of bipolar I (BP I) disorder in youth. Disparities evolved as unintended consequences from investigators' inconsistencies both in translating the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III, DSM-III-R, and DSM-IV criteria and in operationalizing them differently in their standardized assessments. Rates of conservatively diagnosed BP I are lower both in community studies of youths than in adults and from liberally defined BP I in youths. Rates of co-occurring attention-deficit hyperactivity disorder (ADHD) are lower in conservatively than liberally defined children and adolescents with BP I. Rates of both BP I and of ADHD are lower in offspring of BP I probands, and outcome more closely approximates that of adults with BP I in conservatively versus liberally defined children and teens with BP I. Both perspectives can claim evidence for reliability and validity that support their positions. However, the samples are so different that it is difficult to compare studies conducted from these different perspectives.

Pediatric Bipolar Disorder: Subtype Trend and Impact of Behavioral Comorbidities

The diagnosis of pediatric bipolar disorder (PBD) has increased dramatically in community-treated youth in the past 20 years. No previous study has assessed the trend in PBD subtype diagnoses or the impact of clinician-reported behavioral comorbidities (BC) on psychotropic medication prescribing patterns. This study aims: (1) to characterize national trends in PBD visits in relation to PBD subtypes; and (2) to assess differences in socio-demographic PBD subtype diagnostic patterns and psychotropic medications prescribed in PBD visits with and without behavioral comorbidities (w/w/o BC). PBD visits for 1999–2010 from the National Ambulatory Medical Care Survey (NAMCS) data were assessed using population-weighted chi-square and logistic regression analyses. While PBD visit rates were stable across 12 years, the proportional shift of subtype diagnosis from Bipolar I (89.0%) in 1999–2002 to Bipolar Not Otherwise Specified (NOS) (74.1%) in 2007–2010 was notable. Compared with PBD without behavioral comorbidities (w/o BC), PBD visits w/BC had greater proportions of the bipolar-NOS subtype, more males, 2–14-year-olds, and more publicly-insured visits. The prescription of antipsychotics (60% vs. 61%) was common in PBD visits regardless of the presence of behavioral comorbidities. Stimulants were the predominant class prescribed for PBD visits with BC (67.8% vs. 9.4%). Antidepressants were significantly greater in PBD visits without BC (41.6% vs. 21.0%). Overall one-third of PBD youth visits were prescribed antipsychotics concomitant with other psychotropic classes. Behavioral conditions accompanying PBD visits were prominent, suggesting the need for monitoring and evaluating the outcomes of complex medication regimens in community populations.