Development of bipolar disorder in patients with attention-deficit/hyperactivity disorder: A systematic review and meta-analysis of prospective studies

Different brain functional network abnormalities between attention-deficit/hyperactivity disorder youth with and without familial risk for bipolar disorder

Attention-deficit/hyperactivity disorder (ADHD) commonly precedes the initial onset of mania in youth with familial risk for bipolar disorder (BD). Although ADHD youth with and without BD familial risk exhibit different clinical features, associated neuropathophysiological mechanisms remain poorly understood. This study aimed to identify brain functional network abnormalities associated with ADHD in youth with and without familial risk for BD. Resting-state functional magnetic resonance imaging scans were acquired from 37 ADHD youth with a family history of BD (high-risk), 45 ADHD youth without a family history of BD (low-risk), and 32 healthy controls (HC). Individual whole-brain functional networks were constructed, and graph theory analysis was applied to estimate network topological metrics. Topological metrics, including network efficiency, small-worldness and nodal centrality, were compared across groups, and associations between topological metrics and clinical ratings were evaluated. Compared to HC, low-risk ADHD youth exhibited weaker global integration (i.e., decreased global efficiency and increased characteristic path length), while high-risk ADHD youth showed a disruption of localized network components with decreased frontoparietal and frontolimbic connectivity. Common topological deficits were observed in the medial superior frontal gyrus between low- and high-risk ADHD. Distinct network deficits were found in the inferior parietal lobule and corticostriatal circuitry. Associations between global topological metrics and externalizing symptoms differed significantly between the two ADHD groups. Different patterns of functional network topological abnormalities were found in high- as compared to low-risk ADHD, suggesting that ADHD in youth with BD familial risk may represent a phenotype that is different from ADHD alone.

Adults with both bipolar disorder and ADHD

ADHD and bipolar disorder (BP) commonly coexist, and both share key symptoms, depending on affective state and emotional dysregulation. The overlap poses diagnostic challenges and may lead to underdiagnoses. Comorbid cases exhibit worsened symptom burden, increased psychiatric morbidity, admissions, and suicide attempts. Treating BP before ADHD is recommended. Stimulant use combined with mood stabilisers may be effective and relatively safe; however, this review finds that well-designed randomised controlled studies in the area is warranted.

Aberrant Neurofunctional Responses During Emotional and Attentional Processing Differentiate ADHD Youth With and Without a Family History of Bipolar I Disorder

OBJECTIVE

To compare neurofunctional responses in emotional and attentional networks of psychostimulant-free ADHD youth with and without familial risk for bipolar I disorder (BD).

METHODS

ADHD youth with (high-risk, HR, n = 48) and without (low-risk, LR, n = 50) a first-degree relative with BD and healthy controls (n = 46) underwent functional magnetic resonance imaging while performing a continuous performance task with emotional distracters. Region-of-interest analyses were performed for bilateral amygdala (AMY), ventrolateral (VLPFC) and dorsolateral (DLPFC) prefrontal cortex, and anterior (ACC) and posterior cingulate cortex (PCC).

RESULTS

Compared with HC, HR, but not LR, exhibited predominantly left-lateralized AMY, VLPFC, DLPFC, PCC, and rostral ACC hyperactivation to emotional distractors, whereas LR exhibited right VLPFC and bilateral dorsal ACC hypoactivation to attentional targets. Regional responses correlated with emotional and attention symptoms.

CONCLUSION

Aberrant neurofunctional responses during emotional and attentional processing differentiate ADHD youth with and without a family history of BD and correlate with relevant symptoms ratings.

Cause-specific mortality and comorbid neurodevelopmental disorder in 167,515 patients with bipolar disorder: An entire population longitudinal study

OBJECTIVE

Studies addressing premature mortality in bipolar disorder (BD) patients are limited by small sample sizes. Herein, we used almost 99 % of the population of Taiwan to address this issue, and its association with comorbid neurodevelopmental disorders and severe BD.

METHODS

Between 2003 and 2017, we enrolled 167,515 individuals with BD and controls matched 1:4 for sex and birth year from the National Health Insurance Database linked to the Database of National Death Registry in Taiwan. Time-dependent Cox regression models were used to examine cause-specific mortality (all-cause, natural, and unnatural causes [accidents or suicide]).

RESULTS

With adjustments of sex, age, income, urbanization, and physical conditions, suicide was associated with the highest risk of mortality (reported as hazard ratio with 95 % confidence interval: 9.15; 8.53-9.81) among BD patients, followed by unnatural (4.94; 4.72-5.17), accidental (2.15; 1.99-2.32), and natural causes (1.02; 1.00-1.05). Comorbid attention-deficiency hyperactivity disorder did not contribute to the increased risk of cause-specific mortality; however, comorbid autism spectrum disorder (ASD) increased such risks, particularly for natural (3.00; 1.85-4.88) and accidental causes (7.47; 1.80-31.1). Cause-specific mortality revealed a linear trend with the frequency of psychiatric hospitalization (all, p for trend <0.001), and BD patients hospitalized twice or more each year had 34.63-fold increased risk of suicide mortality (26.03-46.07).

CONCLUSIONS

BD patients with a higher frequency of psychiatric hospitalization have the highest risk of suicide mortality, and comorbid ASD was associated with an increased risk of natural and accidental causes of mortality.

Cortical and subcortical structural differences in psychostimulant-free ADHD youth with and without a family history of bipolar I disorder: a cross-sectional morphometric comparison

Although attention-deficit/hyperactivity disorder (ADHD) and a family history of bipolar I disorder (BD) are associated with increased risk for developing BD, their neuroanatomical substrates remain poorly understood. This study compared cortical and subcortical gray matter morphology in psychostimulant-free ADHD youth with and without a first-degree relative with BD and typically developing healthy controls. ADHD youth (ages 10-18 years) with ('high-risk', HR) or without ('low-risk', LR) a first-degree relative with BD and healthy comparison youth (HC) were enrolled. High-resolution 3D T1-weighted images were acquired using a Philips 3.0 T MR scanner. The FreeSurfer image analysis suite was used to measure cortical thickness, surface area, and subcortical volumes. A general linear model evaluated group differences in MRI features with age and sex as covariates, and exploratory correlational analyses evaluated associations with symptom ratings. A total of n = 142 youth (mean age: 14.16 ± 2.54 years, 35.9% female) were included in the analysis (HC, n = 48; LR, n = 49; HR, n = 45). The HR group exhibited a more severe symptom profile, including higher mania and dysregulation scores, compared to the LR group. For subcortical volumes, the HR group exhibited smaller bilateral thalamic, hippocampal, and left caudate nucleus volumes compared to both LR and HC, and smaller right caudate nucleus compared with LR. No differences were found between LR and HC groups. For cortical surface area, the HR group exhibited lower parietal and temporal surface area compared with HC and LR, and lower orbitofrontal and superior frontal surface area compared to LR. The HR group exhibited lower left anterior cingulate surface area compared with HC. LR participants exhibited greater right pars opercularis surface area compared with the HC. Some cortical alterations correlated with symptom severity ratings. These findings suggest that ADHD in youth with a BD family history is associated with a more a severe symptom profile and a neuroanatomical phenotype that distinguishes it from ADHD without a BD family history.

Characterizing the clinical profile of mania without major depressive episodes: a systematic review and meta-analysis of factors associated with unipolar mania

BACKGROUND

The diagnostic concept of unipolar mania (UM), i.e. the lifetime occurrence of mania without major depressive episodes, remains a topic of debate despite the evidence accumulated in the last few years. We carried out a systematic review and meta-analysis of observational studies testing factors associated with UM as compared to bipolar disorder with a manic-depressive course (md-BD).

METHODS

Studies indexed up to July 2022 in main electronic databases were searched. Random-effects meta-analyses of the association between UM and relevant correlates yielded odds ratio (OR) or standardized mean difference (SMD), with 95% confidence intervals (CIs).

RESULTS

Based on data from 21 studies, factors positively or negatively associated with UM, as compared to md-BD, were: male gender (OR 1.47; 95% CI 1.11-1.94); age at onset (SMD -0.25; 95% CI -0.46 to -0.04); number of hospitalizations (SMD 0.53; 95% CI 0.21-0.84); family history of depression (OR 0.55; 95% CI 0.36-0.85); suicide attempts (OR 0.25; 95% CI 0.19-0.34); comorbid anxiety disorders (OR 0.35; 95% CI 0.26-0.49); psychotic features (OR 2.16; 95% CI 1.55-3.00); hyperthymic temperament (OR 1.99; 95% CI 1.17-3.40). The quality of evidence for the association with previous suicide attempts was high, moderate for anxiety disorders and psychotic features, and low or very low for other correlates.

CONCLUSIONS

Despite the heterogeneous quality of evidence, this work supports the hypothesis that UM might represent a distinctive diagnostic construct, with peculiar clinical correlates. Additional research is needed to better differentiate UM in the context of affective disorders, favouring personalized care approaches.

History of Childhood/Adolescence Referral to Speciality Care or Treatment in Adult Patients with Attention-Deficit/Hyperactivity Disorder: Mutual Relations with Clinical Presentation, Psychiatric Comorbidity and Emotional Dysregulation

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition that only rarely remits in adulthood. While several studies underlined differences between child and adult ADHD, the relationship between adult clinical presentation and early referral/treatment has been rarely investigated. In our study, 100 adults with ADHD were recruited and subdivided according to a history of referral to speciality care or treatment with methylphenidate (MPH) during childhood/adolescence. The early referral was associated with a history of disruptive behaviors during childhood/adolescence. Current ADHD symptoms were more pronounced in patients first referred during childhood/adolescence but never treated with MPH. Early MPH treatment was associated with lower rates of mood disorders and lower severity of emotional dysregulation at the time of assessment. Negative emotionality mediated the relationship between MPH treatment and mood disorders comorbidity. ADHD patients first referred during childhood/adolescence are characterized by more externalizing features than those first referred in adulthood. MPH treatment during the developmental age may have a role in preventing mood disorders in patients with ADHD, possibly by reducing emotional dysregulation.

Differential characteristics of bipolar I and II disorders: a retrospective, cross-sectional evaluation of clinical features, illness course, and response to treatment

BACKGROUND

The distinction between bipolar I and bipolar II disorder and its treatment implications have been a matter of ongoing debate. The aim of this study was to examine differences between patients with bipolar I and II disorders with particular emphasis on the early phases of the disorders.

METHODS

808 subjects diagnosed with bipolar I (N = 587) or bipolar II disorder (N = 221) according to DSM-IV criteria were recruited between April 1994 and March 2022 from tertiary-level mood disorder clinics. Sociodemographic and clinical variables concerning psychiatric and medical comorbidities, family history, illness course, suicidal behavior, and response to treatment were compared between the bipolar disorder types.

RESULTS

Bipolar II disorder patients were more frequently women, older, married or widowed. Bipolar II disorder was associated with later "bipolar" presentation, higher age at first (hypo)mania and treatment, less frequent referral after a single episode, and more episodes before lithium treatment. A higher proportion of first-degree relatives of bipolar II patients were affected by major depression and anxiety disorders. The course of bipolar II disorder was typically characterized by depressive onset, early depressive episodes, multiple depressive recurrences, and depressive predominant polarity; less often by (hypo)mania or (hypo)mania-depression cycles at onset or during the early course. The lifetime clinical course was more frequently rated as chronic fluctuating than episodic. More patients with bipolar II disorder had a history of rapid cycling and/or high number of episodes. Mood stabilizers and antipsychotics were prescribed less frequently during the early course of bipolar II disorder, while antidepressants were more common. We found no differences in global functioning, lifetime suicide attempts, family history of suicide, age at onset of mood disorders and depressive episodes, and lithium response.

CONCLUSIONS

Differences between bipolar I and II disorders are not limited to the severity of (hypo)manic syndromes but include patterns of clinical course and family history. Caution in the use of potentially mood-destabilizing agents is warranted during the early course of bipolar II disorder.

Understanding the causal relationships of attention-deficit/hyperactivity disorder with mental disorders and suicide attempt: a network Mendelian randomisation study

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a lifespan neurodevelopmental condition resulting from complex interactions between genetic and environmental risk factors. There is evidence that ADHD is associated with other mental disorders, but it remains unclear whether and in what way a causal relationship exists.

OBJECTIVE

To investigate the direct and indirect causal paths between ADHD and seven common mental disorders.

METHODS

Two-sample network Mendelian randomisation analysis was performed to identify psychiatric disorders causally related to ADHD. Total and direct effects were estimated in an univariable and multivariable setting, respectively. Robustness of results was ensured in three ways: a range of pleiotropy-robust methods, an iterative approach identifying and excluding outliers, and use of up to two genome-wide association studies per outcome to replicate results and calculate subsequently pooled meta-estimates.

RESULTS

Genetic liability to ADHD was independently associated with the risk of anorexia nervosa (OR 1.28 (95% CI 1.11 to 1.47); p=0.001). A bidirectional association was found with major depressive disorder (OR 1.09 (95% CI 1.03 to 1.15); p=0.003 in the forward direction and OR 1.76 (95% CI 1.50 to 2.06); p=4×10-12 in the reverse direction). Moreover, after adjustment for major depression disorder, a direct association with both suicide attempt (OR 1.30 (95% CI 1.16 to 1.547); p=2×10-5) and post-traumatic stress disorder (OR 1.18 (95% CI 1.05 to 1.33); p=0.007) was observed. There was no evidence of a relationship with anxiety, bipolar disorder or schizophrenia.

CONCLUSIONS

This study suggests that ADHD is an independent risk factor for a number of common psychiatric disorders.

CLINICAL IMPLICATIONS

The risk of comorbid psychiatric disorders in individuals with ADHD needs to be considered both in diagnosis and treatment.

Revisiting stimulant use for emotional dysregulation in attention-deficit/hyperactivity disorder (ADHD)

INTRODUCTION

Emotional dysregulation (ED) symptoms are present in a considerable portion of patients with attention-deficit/hyperactivity disorder (ADHD). In recent years, an increasing number of studies investigated the effects of stimulant medications on ED in patients with ADHD.

AREAS COVERED

A narrative review of the literature on stimulant treatment for ED is provided, including controlled and observational clinical studies conducted on pediatric and adult samples and neurobiological investigations. Positive effects of stimulants on irritability have been demonstrated in children. Comorbidity with disruptive behavior disorders (DBD) and disruptive mood dysregulation disorder does not prevent stimulant effectiveness. Methylphenidate has also been found to reduce temper problems, affective instability, and emotional over-reactivity in adults with ADHD, although with variable effect sizes. A variety of adverse emotional effects have been reported, especially at high doses and in special populations. However, several possible confounders of treatment-emergent ED have been highlighted. Finally, according to neuroimaging studies, stimulants may mitigate emotional processing anomalies associated with ADHD.

EXPERT OPINION

The findings are consistent with models including ED within the core features of ADHD. Stimulant treatment should be prioritized over antipsychotics in ADHD-DBD. It remains to be elucidated whether other medications may be more effective in specific populations with ADHD and/or ED.

Regional microstructural differences in ADHD youth with and without a family history of bipolar I disorder

BACKGROUND

Having a first-degree relative with bipolar I disorder (BD) in conjunction with prodromal attention deficit/hyperactivity disorder (ADHD) may represent a unique phenotype that confers greater risk for developing BD than ADHD alone. However, underlying neuropathoetiological mechanisms remain poorly understood. This cross-sectional study compared regional microstructure in psychostimulant-free ADHD youth with ('high-risk', HR) and without ('low-risk', LR) a first-degree relative with BD, and healthy controls (HC).

METHODS

A total of 140 (high-risk, n = 44; low-risk, n = 49; and HC, n = 47) youth (mean age: 14.1 ± 2.5 years, 65 % male) were included in the analysis. Diffusion tensor images were collected and fractional anisotropy (FA) and mean diffusivity (MD) maps calculated. Both tract-based and voxel-based analyses were performed. Correlations between clinical ratings and microstructural metrics that differed among groups were examined.

RESULTS

No significant group differences in major long-distance fiber tracts were observed. The high-risk ADHD group exhibited predominantly higher FA and lower MD in frontal, limbic, and striatal subregions compared with the low-risk ADHD group. Both low-risk and high-risk ADHD groups exhibited higher FA in unique and overlapping regions compared with HC subjects. Significant correlations between regional microstructural metrics and clinical ratings were observed in ADHD groups.

LIMITATIONS

Prospective longitudinal studies will be required to determine the relevance of these findings to BD risk progression.

CONCLUSIONS

Psychostimulant-free ADHD youth with a BD family history exhibit different microstructure alterations in frontal, limbic, and striatal regions compared with ADHD youth without a BD family history, and may therefore represent unique phenotypes relevant to BD risk progression.

Predicting bipolar disorder I/II in individuals at clinical high-risk: Results from a systematic review

INTRODUCTION

No systematic review has estimated the consistency and the magnitude of the risk of developing bipolar disorder I-II (BD-I/II) in individuals at clinical high risk for bipolar disorder (CHR-BD).

METHODS

PubMed and Web of Science databases were searched until April 2022 in this pre-registered (PROSPERO CRD42022346515) PRISMA-compliant systematic review to identify longitudinal studies in individuals meeting pre-defined CHR-BD criteria. The risk of bias was assessed using the Newcastle-Ottawa Scale, and results were systematically synthesized around CHR-BD criteria across follow-up periods and different subgroups.

RESULTS

Altogether, 13 studies were included reporting on nine prospective independent cohorts (n = 678 individuals at CHR-BD). The mean age of participants was 15.7 years (range 10.1-22.6 years), and 54.2 % were females. The most common CHR-BD subgroup was subthreshold mania (55.5 %), followed by BD-Not Otherwise Specified (BD-NOS: 33.3 %). Development of BD I/II ranged from 7.1 % to 23.4 % after 2 years. Development of BD-I ranged from 3.4 % at 4 years to 23 % at 8 years. Development of BD-II ranged from 10 % at 2 years to 63.8 % at 4 years. The risk of developing BD-I appeared highest in those meeting BD-NOS criteria (23 % at eight years). Predictors of development of BD were identified but remained mostly unreplicated. The quality of the included studies was moderate (NOS = 5.2 ± 1.1).

CONCLUSIONS

Emerging data from research studies point towards the promising utility of CHR-BD criteria. These studies may pave the way to the next generation of research, implementing detection, prognostication, and preventive interventions in individuals at CHR-BD identified and followed in clinical practice.

Meta-analysis of personal and familial co-occurrence of Attention Deficit/Hyperactivity Disorder and Bipolar Disorder

BACKGROUND

Attention Deficit Disorder / Hyperactivity (ADHD) and Bipolar Disorder (BD) are highly comorbid disorders. Studies have raised the hypothesis of shared genetic, neurobiological, and clinical factors. This would entail an excess risk of co-occurrence of both disorders.

OBJECTIVE

We present the first meta-analysis of individual and familial associations between ADHD and BD.

METHODS

From 2688 references, 59 were included, with a total of 550,379 ADHD patients, 57,799 BD patients and 12,608,137 controls.

RESULTS

Personal history of ADHD increased the risk of BD (OR = 6.06), and conversely individuals with BD had an increased risk of ADHD (OR = 8.94). First-degree relatives of ADHD patients had an increased risk of BD (OR = 1.94). Offspring of individuals with BD had a higher risk for ADHD (OR = 2.33). Finally, first-degree relatives of BD patients had an increased risk of ADHD (OR = 2.71).

CONCLUSION

We show a clear epidemiological overlap between ADHD and BD, as well as a strong familial association which advocates in favor of a more systematic screening.

Comparison of bipolar disorder type II and major depressive disorder

OBJECTIVE

Compare patients diagnosed as DSM-5 type II bipolar disorder (BD2) vs. major depressive disorder (MDD).

METHODS

We compared characteristics of 3246 closely and repeatedly evaluated, consenting, adult patient-subjects (n = 706 BD2, 2540 MDD) at a specialty clinic using bivariate methods and multivariable modeling.

RESULTS

Factors more associated with BD2 than MDD included: [a] descriptors (more familial psychiatric, mood and bipolar disorders and suicide; younger at onset, diagnosis and first-treatment; more education; more unemployment; fewer marriages and children; higher cyclothymic, hyperthymic and irritable temperament ratings, lower anxious); [b] morbidity (more hypomanic, mixed or panic first episodes; more co-occurring general medical diagnoses, more Cluster B personality disorder diagnoses and ADHD; more alcohol and drug abuse and smoking; shorter depressive episodes and interepisode periods; lower intake ratings of depression and anxiety, higher for hypomania; far more mood-switching with antidepressants; lower %-time depressed; DMI > MDI course-pattern in BD2; more suicide attempts and violent suicidal behavior); [c] item-scores with intake HDRS₂₁ higher for suicidality, paranoia, anhedonia, guilt, and circadian variation; lower somatic anxiety, depressed mood, insight, hypochondriasis, agitation, and insomnia; and [d] treatment (more lithium, mood-stabilizing anticonvulsants and antipsychotics, less antidepressants and benzodiazepines).

CONCLUSIONS

BD2 and MDD subjects differed greatly in many descriptive, psychopathological and treatment measures, notably including more familial risk, earlier onset, more frequent recurrences and greater suicidal risk with BD2. Such differences can contribute to improving differentiation of the disorders and planning for their treatment.

Long-term treatment of adult ADHD in a naturalistic setting: clinical predictors of attrition, medication choice, improvement, and response

Objectives: The aim of this study was to identify clinical predictors of treatment attrition, medication choice, improvement and response to pharmacotherapy in adult attention-deficit/hyperactivity disorder (ADHD). Methods: 150 ADHD patients were enrolled and naturalistically followed-up for at least 4 months. Conners' Adult ADHD Rating Scales-Observer: Screening Version (CAARS-O:SV) were used to measure ADHD severity. Results: 58 subjects (38.7%) were lost at follow-up, while 75 (50%) completed follow-up assessment, on average after 26.05 ± 11.99 weeks; 35 were treated with atomoxetine (ATX) and 40 with methylphenidate (MPH). Treatments were moderately effective (d = 0.72) and 37 patients (49.3%) were responders (≥30% CAARS-O:SV decrease). Patients lost at follow-up had lower inattentive symptoms, less generalized anxiety and family history of bipolar disorder, more amphetamine use disorder than follow-up completers. Compared to ATX-treated subjects, MPH-treated patients had greater severity of hyperactivity/impulsivity and were more frequently diagnosed with alcohol use disorder. While MPH and ATX showed similar efficacy, more pronounced improvements were observed in patients with combined ADHD, anxiety and substance use disorders. ADHD severity and comorbid substance use positively predicted response. Conclusions: Consensus-based hierarchical treatment of ADHD comorbidity is not consistently supported. Comorbid anxiety, mood and substance use disorders should not discourage the treatment of adult ADHD.

Comorbidities in Youth with Bipolar Disorder: Clinical Features and Pharmacological Management

BACKGROUND

Bipolar Disorder (BD) is a highly comorbid condition, and rates of cooccurring disorders are even higher in youth. Comorbid disorders strongly affect clinical presentation, natural course, prognosis, and treatment.

METHODS

This review focuses on the clinical and treatment implications of the comorbidity between BD and Attention-Deficit/Hyperactivity Disorder, disruptive behavior disorders (Oppositional Defiant Disorder and/or Conduct Disorder), alcohol and substance use disorders, Autism Spectrum Disorder, anxiety disorders, Obsessive-Compulsive Disorder, and eating disorders.

RESULTS

These associations define specific conditions which are not simply a sum of different clinical pictures, but occur as distinct and complex combinations with specific developmental pathways over time and selective therapeutic requirements. Pharmacological treatments can improve these clinical pictures by addressing the comorbid conditions, though the same treatments may also worsen BD by inducing manic or depressive switches.

CONCLUSION

The timely identification of BD comorbidities may have relevant clinical implications in terms of symptomatology, course, treatment and outcome. Specific studies addressing the pharmacological management of BD and comorbidities are still scarce, and information is particularly lacking in children and adolescents; for this reason, the present review also included studies conducted on adult samples. Developmentally-sensitive controlled clinical trials are thus warranted to improve the prognosis of these highly complex patients, requiring timely and finely personalized therapies.

Clinical correlates of comorbid attention deficit hyperactivity disorder in adults suffering from bipolar disorder: A meta-analysis

OBJECTIVE

Attention deficit hyperactivity disorder is a frequent comorbid condition in adults with bipolar disorder. We performed a meta-analysis aimed at assessing sociodemographic and clinical correlates of attention deficit hyperactivity disorder in bipolar disorder.

METHOD

We searched main electronic databases up to June 2021. Random-effects meta-analyses, with relevant meta-regression and quality-based sensitivity analyses, were carried out to estimate the association between attention deficit hyperactivity disorder and putative correlates, grading the quality of evidence.

RESULTS

We included 43 studies, based on 38 independent samples. Attention deficit hyperactivity disorder participants were more likely to be males (odds ratio = 1.46; p < 0.001) and unemployed (odds ratio = 1.45; p = 0.045), and less likely to be married (odds ratio = 0.62; p = 0.014). They had an earlier onset of bipolar disorder (standardized mean difference = -0.36; p < 0.001); more mood episodes (standardized mean difference = 0.35; p = 0.007), particularly depressive (standardized mean difference = 0.30; p = 0.011) and mixed (standardized mean difference = 0.30; p = 0.031) ones; higher odds of using antidepressants (odds ratio = 1.80; p = 0.024) and attempted suicides (odds ratio = 1.83; p < 0.001) and lower odds of psychotic features (odds ratio = 0.63; p = 0.010). Moreover, they were more likely to have generalized anxiety disorder (odds ratio = 1.50; p = 0.019), panic disorder (odds ratio = 1.89; p < 0.001), social phobia (odds ratio = 1.61; p = 0.017), eating disorders (odds ratio = 1.91; p = 0.007), antisocial personality disorder (odds ratio = 3.59; p = 0.004) and substance (odds ratio = 2.29; p < 0.001) or alcohol (odds ratio = 2.28; p < 0.001) use disorders. Quality of the evidence was generally low or very low for the majority of correlates, except for bipolar disorder onset and alcohol/substance use disorders (high), and suicide attempts (moderate).

CONCLUSION

Comorbid bipolar disorder/attention deficit hyperactivity disorder may have some distinctive clinical features including an earlier onset of bipolar disorder and higher comorbid alcohol/substance use disorder rates. Further research is needed to identify additional clinical characteristics of this comorbidity.

Symptom Profiles, But Not Prefrontal Neurochemistry, Differentiate ADHD Youth With and Without a Family History of Bipolar I Disorder

Objective: To identify clinical and central features that differentiate ADHD youth with and without familial risk for bipolar I disorder (BD). Methods: Psychostimulant-free ADHD youth (10-18 years) with and without a first-degree relative with BD and healthy controls were enrolled. Bilateral ventrolateral prefrontal cortex (VLPFC) proton magnetic resonance spectroscopy (¹H MRS) scans and a range of symptom ratings were performed. Results: A total of n = 145 youth were enrolled. ADHD youth with a family history of BD exhibited greater manic and depressive symptom severity, ADHD hyperactivity/impulsive symptom severity, and higher parent-reported ratings of dysregulation compared with ADHD youth without a BD family history. Although VLPFC metabolite levels did not differ across groups, choline levels in the left VLPFC correlated with different symptom ratings. Conclusion: Symptom profiles including more severe mood and externalizing symptoms, but not VLPFC neurochemistry, differentiate psychostimulant-free ADHD youth with and without a family history of BD.

Understanding the development of bipolar disorder and borderline personality disorder in young people: a meta-review of systematic reviews

BACKGROUND

There is ongoing debate on the nosological position of bipolar disorder (BD) and borderline personality disorder (BPD). Identifying the unique and shared risks, developmental pathways, and symptoms in emerging BD and BPD could help the field refine aetiological hypotheses and improve the prediction of the onset of these disorders. This study aimed to: (a) systematically synthesise the available evidence from systematic reviews (SRs) and meta-analyses (MAs) concerning environmental, psychosocial, biological, and clinical factors leading to the emergence of BD and BPD; (b) identify the main differences and common features between the two disorders to characterise their complex interplay and, (c) highlight remaining evidence gaps.

METHODS

Data sources were; PubMed, PsychINFO, Embase, Cochrane, CINAHL, Medline, ISI Web of Science. Overlap of included SRs/MAs was assessed using the corrected covered area process. The methodological quality of each included SR and MA was assessed using the AMSTAR.

RESULTS

22 SRs and MAs involving 249 prospective studies met eligibility criteria. Results demonstrated that family history of psychopathology, affective instability, attention deficit hyperactivity disorder, anxiety disorders, depression, sleep disturbances, substance abuse, psychotic symptoms, suicidality, childhood adversity and temperament were common predisposing factors across both disorders. There are also distinct factors specific to emerging BD or BPD.

CONCLUSIONS

Prospective studies are required to increase our understanding of the development of BD and BPD onset and their complex interplay by concurrently examining multiple measures in BD and BPD at-risk populations.

Familial risk for bipolar I disorder is associated with erythrocyte omega-3 polyunsaturated fatty acid deficits in youth with attention-deficit hyperactivity disorder

Although attention-deficit/hyperactivity disorder (ADHD) and a family history of bipolar I disorder (BD) increase the risk for developing BD, associated pathoetiological mechanisms remain poorly understood. One candidate risk factor is a neurodevelopmental deficiency in omega-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated erythrocyte EPA+DHA biostatus in psychostimulant-free ADHD youth with ('high-risk', HR) and without ('low-risk', LR) a first-degree relative with BD, and healthy controls (HC). Erythrocyte EPA+DHA composition was determined by gas chromatography, and symptom ratings were performed. A total of n = 123 (HR, n = 41; LR, n = 42; HC, n = 40) youth (mean age: 14.4 ± 2.5 years) were included in the analysis. Compared with HC, erythrocyte EPA+DHA composition was significantly lower in HR (-13%) but not LR (-3%), and there was a trend for HR to be lower than LR (-11%). Both HR and LR differed significantly from HC on all symptom ratings. HR had greater ADHD hyperactivity/impulsive symptom severity, manic symptom severity, and higher parent-reported ratings of internalization, externalization, and dysregulation, compared with LR. ADHD youth with a BD family history exhibit erythrocyte EPA+DHA deficits and a more severe clinical profile, including greater manic and dysregulation symptoms, compared with ADHD youth without a BD family history.

Differentiation and comorbidity of bipolar disorder and attention deficit and hyperactivity disorder in children, adolescents, and adults: A clinical and nosological perspective

Bipolar Disorder (BD) and Attention Deficit and Hyperactivity Disorder (ADHD) are mental disorders with high degree of lifetime comorbidity. Both BD and ADHD are disorders with onset in childhood and early adolescence. Both disorders are often undiagnosed, misdiagnosed, and sometimes overdiagnosed, leading to high rates of morbidity and disability. The psychiatric and behavioral symptoms associated with ADHD and BD have significant overlap. Albeit the existence of a large body of literature, it is far from being clear whether comorbidity can be explained by the confounding overlap of operationally defined criteria or whether it reflects a genuine comorbidity of two biologically distinct disorders. The aim of this paper is to recognize and/or differentiate the pattern of ADHD across the course of BD from a nosological point of view, focusing on specific clinical and neurobiological dimensions. We found that some critical issues may help to fulfill the purpose of our perspective. We suggest that the relationship between ADHD and BD, based on clinical, developmental, and epidemiological commonalities, can be better clarified using four different scenarios.