Medical and substance-related comorbidity in bipolar disorder: translational research and treatment opportunities

Nutraceuticals in mood disorders: current knowledge and future directions

PURPOSE OF REVIEW

There is a large evidence base of clinical trials that have investigated the efficacy of a range of nutraceuticals on mood disorders. The aim of the current review is to provide an update regarding the efficacy and safety of nutraceutical agents in mood disorders and to highlight considerations for future research.

RECENT FINDINGS

Nutraceuticals such as omega-3, probiotics, zinc, saffron and curcumin have been recommended as adjunctive interventions to standard treatments for people with depression, while St John's wort has been recommended as a monotherapy. In contrast, less research has been devoted to investigating the effect of nutraceuticals in bipolar disorder, with omega-3 being weakly recommended as an adjunctive to standard treatments. Although the safety profile of most nutraceuticals appears acceptable, more insight into the long-term effects within a range of cohorts is recommended.

SUMMARY

There are a number of nutraceuticals that have clinical trial support for their use as either adjunctive interventions for depression; however, there is mostly limited support for their use in bipolar disorder. Further randomized controlled trials that take into consideration a number of emerging mechanisms, potential nutraceutical combinations and factors that may predict treatment response are required to inform clinical use.

Prevalence and association of comorbid substance dependence on the course and outcome of bipolar disorder: Findings from the bipolar disorder course and outcome study from India (BiD-CoIN study)

AIM

To evaluate the prevalence of substance use disorder (SUD) and its association with the course and outcome of bipolar disorder (BD).

MATERIALS AND METHODS

A total of 773 patients with BD were recruited from 14 centers in different parts of India, and they were evaluated for the prevalence of comorbid substance dependence, course and outcome, subjective cognitive functioning, and disability.

RESULTS

About one-fourth (22.9%) of the participants had one or more substance dependence. In terms of specific substance of abuse, 136 (17.6%) had nicotine dependence, 80 (10.3%) patients had alcohol dependence, 13 (1.7%) had cannabis dependence, and nine (1.2%) had opioid dependence. Compared to those without comorbid substance dependence, those with a dual diagnosis (i.e., using at least one substance in a dependent pattern) were less educated, more often males, more often currently single, more often employed, had a lower number of depressive episodes per year of illness, had a higher number of manic and mixed episodes per year of illness in the first 5 years of illness, had a higher level of disability, and more often had a history of hospitalization and a history of receiving electroconvulsive therapy (ECT); also, a higher proportion of them had manic predominant polarity, more often had recurrent mania course, and were more often receiving a combination of lithium and valproate.

CONCLUSION

About one-fourth of BD patients have comorbid SUDs, and presence of SUD has a negative impact on the course and outcome of BD.

Machine Learning Prediction of Comorbid Substance Use Disorders among People with Bipolar Disorder

Substance use disorder (SUD) is a common comorbidity in individuals with bipolar disorder (BD), and it is associated with a severe course of illness, making early identification of the risk factors for SUD in BD warranted. We aimed to identify, through machine-learning models, the factors associated with different types of SUD in BD. We recruited 508 individuals with BD from a specialized unit. Lifetime SUDs were defined according to the DSM criteria. Random forest (RF) models were trained to identify the presence of (i) any (SUD) in the total sample, (ii) alcohol use disorder (AUD) in the total sample, (iii) AUD co-occurrence with at least another SUD in the total sample (AUD+SUD), and (iv) any other SUD among BD patients with AUD. Relevant variables selected by the RFs were considered as independent variables in multiple logistic regressions to predict SUDs, adjusting for relevant covariates. AUD+SUD could be predicted in BD at an individual level with a sensitivity of 75% and a specificity of 75%. The presence of AUD+SUD was positively associated with having hypomania as the first affective episode (OR = 4.34 95% CI = 1.42-13.31), and the presence of hetero-aggressive behavior (OR = 3.15 95% CI = 1.48-6.74). Machine-learning models might be useful instruments to predict the risk of SUD in BD, but their efficacy is limited when considering socio-demographic or clinical factors alone.

Allostatic load and systemic comorbidities in psychiatric disorders

Psychiatric disorders are complex, disabling, and chronic conditions that are often accompanied by one or more systemic medical comorbidities. In this narrative review, we provide an overview of the allostatic load concept, which represents a multi-system dysregulation in response to chronic stress and link it to systemic comorbidities associated with psychiatric disorders. We synthesized published literature gathered using Medline (Ovid), Scopus, and PsychInfo and identified a high frequency of systemic comorbidities for both mood and psychotic disorders. The identified cardiovascular, metabolic, and immune comorbidities may represent the result of chronic wear and tear caused by a complex interaction between chronic psychosocial stress, health risk behaviors, pharmacological stressors, and the biological systems involved in the development of allostatic load. These findings support the notion that psychiatric disorders should be re-conceptualized as systemic disorders, affecting the brain and systemic biological pathways in an interconnected fashion to result in systemic comorbidities. We suggest that the multi-systemic and multi-dimensional approach that drives the allostatic load concept should be considered for understanding comorbidities in vulnerable psychiatric patients.

"Supporting Wellness": A depression and bipolar support alliance mixed-methods investigation of lived experience perspectives and priorities for mood disorder treatment

BACKGROUND

The lived experience of people with mood disorders may be leveraged to inform priorities for research, define key treatment outcomes, and support decision-making in clinical care. The aim of this mixed-methods project was to provide insight into how people with depression and bipolar disorder experience the impact of symptoms, their treatment preferences, and their definitions of wellness.

METHODS

The project was implemented in two phases. In Phase 1, community-based participatory research was used to develop a web-based survey enquiring about living with a mood disorder, treatment experiences, and wellness priorities. In Phase 2, a series of focus groups were conducted to explore aspects of wellness in greater detail.

RESULTS

Respondents (n= 6153) described the symptoms of mood disorders as having a significant, chronic impact on their lives. A holistic approach to treatment was desired by participants, but not necessarily experienced. Qualitative findings were used to further describe four highly ranked wellness priorities identified in the survey: ability to act independently or according to my own will; purpose in life; getting through the day; and contentment.

LIMITATIONS

Experience of a mood disorder was self-reported, and no formal confirmation of diagnosis occurred. Although the survey could not incorporate all possible wellness definitions, this was supplemented by qualitative focus groups.

CONCLUSION

The present findings provide important insights from the perspectives of individuals with lived experience of mood disorders. Implications of this for research and clinical practice are discussed, particularly with regards to measurement-based care and use of wellness-oriented clinical outcome assessments.

The effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder

Background

Persistent impairment in cognitive function has been described in euthymic individuals with bipolar disorder. Collective work indicates that obesity is associated with reduced cognitive function in otherwise healthy individuals. This sub-group post-hoc analysis preliminarily explores and examines the association between overweight/obesity and cognitive function in euthymic individuals with bipolar disorder.

Methods

Euthymic adults with DSM-IV-TR-defined bipolar I or II disorder were enrolled. Subjects included in this post-hoc analysis (n = 67) were divided into two groups (normal weight, body mass index [BMI] of 18.5–24.9kg/m2; overweight/obese, BMI≥25.0kg/m2). Demographic and clinical information were obtained at screening. At baseline, study participants completed a comprehensive cognitive battery to assess premorbid IQ, verbal learning and memory, attention and psychomotor processing speed, executive function, general intellectual abilities, recollection and habit memory, as well as self-perceptions of cognitive failures.

Results

BMI was negatively correlated with attention and psychomotor processing speed as measured by the Digit Symbol Substitution Test (P<0.01). Overweight and obese bipolar individuals had a significantly lower score on the Verbal Fluency Test when compared to normal weight subjects (P<0.05). For all other measures of cognitive function, non-significant trends suggesting a negative association with BMI were observed, with the exception of measures of executive function (i.e. Trail Making Test B) and recollection memory (i.e. process-dissociation task).

Conclusion

Notwithstanding the post-hoc methodology and relatively small sample size, the results of this study suggest a possible negative effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder. Taken together, these data provide the impetus for more rigorous evaluation of the mediational role of overweight/obesity (and other medical co-morbidity) on cognitive function in psychiatric populations.

Association between CANCA1C gene rs1034936 polymorphism and alcohol dependence in bipolar disorder

INTRODUCTION

Bipolar disorder (BD) is a highly heritable and disabling mental illness, commonly associated with substance abuse, being alcohol abuse the most frequent. Comorbid BD and substance abuse disorders are often associated with high levels of health service utilization and destabilization of the course of illness resulting in poor treatment outcomes. Although recent genome-wide association studies have detected a number of risk genes for BD, the data is still sparse and inconclusive for those genes that may contribute to the increased risk of comorbid alcohol abuse (AA) in BD. The primary aim of the present study was to investigate the effects of 46 single-nucleotide polymorphisms (SNPs) within eight genes on different phenotypes of BD patients, such as comorbid alcohol abuse. We further assessed clinical variables associated with AA.

METHODS

One-hundred fifty-eight BD I and II patients were enrolled in a naturalistic cohort study. Genomic DNA of 92 patients was extracted from whole blood using standard procedures and 46 tag SNPs in eight genes of interest (ANK, CACNA1C, CACNB2, FKBP5, GRM7, ITIH3, SYNE1 and TCF4) were genotyped.

RESULTS

Seventy-one patients out of 158 (45%) satisfied diagnostic criteria for comorbid AA. Among 46 SNPs analyzed, the only SNP associated with comorbid AA was rs1034936 polymorphism in the CANCA1C gene. This polymorphism was also associated with lifetime cocaine abuse, manic switch and current atypical antipsychotics.

CONCLUSIONS

Our findings suggest a role of rs1034936 CACNA1C gene variant in BD-AA group. Despite their preliminary nature, the present results may provide new insight on mechanisms underlying AA in BD.

Adiponectin is decreased in bipolar depression

Objectives: Bipolar disorder (BD) is often accompanied by medical comorbidities, which affect illness course and prognosis. Adipokines may not only be involved in the aetiopathogenetic mechanisms of these comorbidities; there might be an association between adipokines and the neuropsychiatric core features of BD such as mood disturbances and cognitive deficits.Methods: In this investigation, fasting blood samples from 120 individuals with BD (75 euthymic and 45 with mild depressive symptoms) and 68 control subjects were taken and adiponectin and leptin concentrations were analysed.Results: We found that, in female participants, adiponectin levels differed significantly between patients and controls indicating lower levels in individuals with BD, even after controlling for BMI (F(1,92) = 4.65, P = 0.034, partial η² = 0.05). After stratification by mood status we found a significant difference in adiponectin between controls, euthymic and depressive patients (F(2, 180) = 4.90, P = 0.008, partial η² = 0.05).Conclusions: This investigation confirms previous findings of an association between low adiponectin levels and depressive state in individuals with BD. Beyond its immediate effect on central nervous system function, adiponectin might interfere with pathophysiological mechanisms of BD and its somatic comorbidities via involvement in metabolic and inflammatory processes.

Bipolar disorder in Asia: Illness course and contributing factors

BACKGROUND

Epidemiological studies analysing the course of Bipolar Disorder (BD) are relatively rare in the Asian context, contributing to the uncertainty regarding the prevalent course patterns and factors influencing such patterns. The current review identifies the regional characteristics of BD course patterns and the associated factors.

METHODS

A review of the existing literature was done using 'PubMed' and 'Cochrane' databases which yielded 145 studies including those from all 48 Asian countries. Relevant discussions from the Western literature were incorporated.

RESULTS

Regional and cross-national studies reveal a mania-predominant course in BD in Asian countries. Prolonged depressive episodes and comorbid anxiety disorders worsen the course of BD-II. Certain risk factors such as the young age of onset and greater episode frequency are useful predictors of bipolar diatheses. Substance use disorder comorbidity is more prevalent in males whereas depression and suicidal behaviours are more frequent in females with BD. Comorbid anxiety and personality disorders also encumber the illness course. Logistic reasons and ignorance of side-effects were specifically associated with poor adherence. An 'eveningness' chronotype and poor sleep quality were associated with frequent recurrences. Seasonal patterns vary among men and women, especially for depressive episodes.

LIMITATIONS

The effects of treatment and childhood BD course features were not discussed.

CONCLUSIONS

There are region-specific characteristics in bipolar illness course and factors influencing such course patterns compared to the rest of the World. Future research from Asia shall attempt to study the neurobiological underpinnings of such characteristics and plan appropriate strategies to address the same.

Association between antipsychotic drug use and cataracts in patients with bipolar disorder: A population-based, nested case-control study

BACKGROUND

No previous study has focused on the association between use of antipsychotic drugs and the development of cataracts in patients with bipolar disorder (BD); hence, we aimed to examine this association in the present study.

METHODS

We conducted a retrospective nested case-control study using data from the National Health Insurance Database of Taiwan between 2000 and 2011. A total of 3292 BD patients, 1684 with cataracts and 1608 controls matched for age, sex, and index date, were included. Antipsychotic drug exposure was categorized by type of drug and duration of use. A conditional logistic regression analysis was used to analyze the association.

RESULTS

Among BD patients, we found significantly reduced odds ratio (OR) of cataract development among past (adjusted OR (AOR), 0.74; 95% confidence interval (CI), 0.62-0.89; p=0.001) and continuous users (AOR, 0.71; 95% CI, 0.59-0.85; p<0.001) of atypical antipsychotics. No association was found between the odds of cataract development and typical antipsychotics. Besides, concomitant use of antidepressants (AOR, 1.23; 95% CI, 1.06-1.43; p=0.007) and mood stabilizers (AOR, 1.23; 95% CI, 1.06-1.42; p=0.007) were associated with increased odds of cataract development.

LIMITATIONS

Some important contributors to cataract development such as family history of cataract, smoking and alcohol exposure could not be measured from the claims data and this may confound the results.

CONCLUSIONS

Reduced odds of cataract were found in patients with BD taking atypical antipsychotics. However, given that BD patients often have risk factors for developing cataract, regular ocular evaluations are recommended for those treated with antipsychotics drugs.

Glutamatergic and HPA-axis pathway genes in bipolar disorder comorbid with alcohol- and substance use disorders

Glutamatergic neurotransmission has been shown to be dysregulated in bipolar disorder (BD), alcohol use disorder (AUD) and substance use disorder (SUD). Similarly, disruption in the hypothalamic-pituitary-adrenal (HPA)-axis has also been observed in these conditions. BD is often comorbid with AUD and SUD. The effects of the glutamatergic and HPA systems have not been extensively examined in individuals with BD-AUD and BD-SUD comorbidity. The aim of this investigation was to determine whether variants in the glutamatergic pathway and HPA-axis are associated with BD-AUD and BD-SUD comorbidity. The research cohort consisted of 498 individuals with BD type I from the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD). A subset of the cohort had comorbid current AUD and current SUD. A total of 1935 SNPs from both the glutamatergic and HPA pathways were selected from the STEP-BD genome-wide dataset. To identify population stratification, IBS clustering was performed using the program Plink 1.07. Single SNP association and gene-based association testing were conducted using logistic regression. A pathway analysis of glutamatergic and HPA genes was performed, after imputation using IMPUTE2. No single SNP was associated with BD-AUD or BD-SUD comorbidity after correction for multiple testing. However, from the gene-based analysis, the gene PRKCI was significantly associated with BD-AUD. The pathway analysis provided overall negative findings, although several genes including GRIN2B showed high percentage of associated SNPs for BD-AUD. Even though the glutamatergic and HPA pathways may not be involved in BD-AUD and BD-SUD comorbidity, PRKCI deserves further investigation in BD-AUD.

New alterations at potentially regulated regions of the Glial Derived Neurotrophic Factor gene in bipolar disorder

INTRODUCTION

Glial Derived Neurotrophic Factor (GDNF) plays an important role in the survival and differentiation of neurons. We examined 5'upstream and 3' untranslated region of the GDNF gene by PCR amplification and direct sequencing to explore the effect of alteration in the potentially regulated part of GDNF in bipolar disorder.

MATERIALS AND METHODS

Sixty-six patients with bipolar disorder, 27 first degree relatives of these patients and 56 healthy volunteers were screened for mutations and polymorphisms in GDNF gene.

RESULTS

Seven previously reported polymorphisms and additional three novel allele variants of GDNF were detected. Association test of rs2075680 C>A SNP showed significant difference between patients and healthy subjects with higher allele frequency in healthy subjects performing Chi-square test. However, there was no significant difference after multiple test corrections between groups. There were no significant differences in association test of rs2075680 C>A SNP between first degree relatives and healthy volunteers/patients. rs142426358 T>C SNP was seen only in one patient with an early age of illness onset. New T>A alterations were found in chromosome locations 5:37812784 and 5:37812782 in two male bipolar disorder patients with age of illness onset 12 and 24 years.

LIMITATIONS

The sample size was relatively small.

DISCUSSION

Our study proposes the suggestive association between polymorphisms in the potential regulatory sites of GDNF and bipolar disorder.

Advancing biomarker research: utilizing 'Big Data' approaches for the characterization and prevention of bipolar disorder

OBJECTIVE

To provide a strategic framework for the prevention of bipolar disorder (BD) that incorporates a 'Big Data' approach to risk assessment for BD.

METHODS

Computerized databases (e.g., Pubmed, PsychInfo, and MedlinePlus) were used to access English-language articles published between 1966 and 2012 with the search terms bipolar disorder, prodrome, 'Big Data', and biomarkers cross-referenced with genomics/genetics, transcriptomics, proteomics, metabolomics, inflammation, oxidative stress, neurotrophic factors, cytokines, cognition, neurocognition, and neuroimaging. Papers were selected from the initial search if the primary outcome(s) of interest was (were) categorized in any of the following domains: (i) 'omics' (e.g., genomics), (ii) molecular, (iii) neuroimaging, and (iv) neurocognitive.

RESULTS

The current strategic approach to identifying individuals at risk for BD, with an emphasis on phenotypic information and family history, has insufficient predictive validity and is clinically inadequate. The heterogeneous clinical presentation of BD, as well as its pathoetiological complexity, suggests that it is unlikely that a single biomarker (or an exclusive biomarker approach) will sufficiently augment currently inadequate phenotypic-centric prediction models. We propose a 'Big Data'- bioinformatics approach that integrates vast and complex phenotypic, anamnestic, behavioral, family, and personal 'omics' profiling. Bioinformatic processing approaches, utilizing cloud- and grid-enabled computing, are now capable of analyzing data on the order of tera-, peta-, and exabytes, providing hitherto unheard of opportunities to fundamentally revolutionize how psychiatric disorders are predicted, prevented, and treated. High-throughput networks dedicated to research on, and the treatment of, BD, integrating both adult and younger populations, will be essential to sufficiently enroll adequate samples of individuals across the neurodevelopmental trajectory in studies to enable the characterization and prevention of this heterogeneous disorder.

CONCLUSIONS

Advances in bioinformatics using a 'Big Data' approach provide an opportunity for novel insights regarding the pathoetiology of BD. The coordinated integration of research centers, inclusive of mixed-age populations, is a promising strategic direction for advancing this line of neuropsychiatric research.

Allostasis as a conceptual framework linking bipolar disorder and addiction

Bipolar disorders (BDs) and addictions constitute reciprocal risk factors and are best considered under a unitary perspective. The concepts of allostasis and allostatic load (AL) may contribute to the understanding of the complex relationships between BD and addictive behaviors. Allostasis entails the safeguarding of reward function stability by recruitment of changes in the reward and stress system neurocircuitry and it may help to elucidate neurobiological underpinnings of vulnerability to addiction in BD patients. Conceptualizing BD as an illness involving the cumulative build-up of allostatic states, we hypothesize a progressive dysregulation of reward circuits clinically expressed as negative affective states (i.e., anhedonia). Such negative affective states may render BD patients more vulnerable to drug addiction, fostering a very rapid transition from occasional drug use to addiction, through mechanisms of negative reinforcement. The resulting addictive behavior-related ALs, in turn, may contribute to illness progression. This framework could have a heuristic value to enhance research on pathophysiology and treatment of BD and addiction comorbidity.

Selfish brain and neuroprogression in bipolar disorder

Bipolar disorder is associated with increases in mortality rates due to metabolic complications when compared to the general population. The "selfish brain" theory postulates that the CNS modulates energy metabolism in the periphery in order to prioritize its own demand and offers an heurist value framework to understand how and why metabolic abnormalities develop in the course of BD. Mood episodes, especially those of manic polarity are neurotoxic, because of the acute release of the neurotransmitters dopamine and glutamate, oxidative species, inflammatory cytokines and the deprivation of neuroprotective factors, such as neurotrophins. The cell loss and malfunctioning require from the brain an extra effort to repair itself, which will demand energetic supplies. Application of "selfish brain" theory in BD can potentially offer new insights about how to prevent and treat metabolic complications in BD.

The diagnosis and treatment of bipolar disorder: recommendations from the current s3 guideline

BACKGROUND

Bipolar disorder is a serious mental illness, characterized by frequent recurrences and major comorbidities. Its consequences can include suicide.

METHODS

An S3 guideline for the treatment of bipolar disorder was developed on the basis of a systematic literature search, evaluation of the retrieved publications, and a formal consensus-finding procedure. Several thousand publications were screened, and 611 were included in the analysis, including 145 randomized controlled trials (RCT).

RESULTS

Bipolar disorder should be diagnosed as early as possible. The most extensive evidence is available for pharmacological monotherapy; there is little evidence for combination therapy, which is nonetheless commonly given. The appropriate treatment may include long-term maintenance treatment, if indicated. The treatment of mania should begin with one of the recommended mood stabilizers or antipsychotic drugs; the number needed to treat (NNT) is 3 to 13 for three weeks of treatment with lithium or atypical antipsychotic drugs. The treatment of bipolar depression should begin with quetiapine (NNT = 5 to 7 for eight weeks of treatment), unless the patient is already under mood-stabilizing treatment that can be optimized. Further options in the treatment of bipolar depression are the recommended mood stabilizers, atypical antipsychotic drugs, and antidepressants. For maintenance treatment, lithium should be used preferentially (NNT = 14 for 12 months of treatment and 3 for 24 months of treatment), although other mood stabilizers or atypical antipsychotic drugs can be given as well. Psychotherapy (in addition to any pharmacological treatment) is recommended with the main goals of long-term stabilization, prevention of new episodes, and management of suicidality. In view of the current mental health care situation in Germany and the findings of studies from other countries, it is clear that there is a need for prompt access to need-based, complex and multimodal care structures. Patients and their families need to be adequately informed and should participate in psychiatric decision-making.

CONCLUSION

Better patient care is needed to improve the course of the disease, resulting in better psychosocial function. There is a need for further high-quality clinical trials on topics relevant to routine clinical practice.

The clinical implications of cognitive impairment and allostatic load in bipolar disorder

BACKGROUND

Allostatic load (AL) relates to the neural and bodily "wear and tear" that emerge in the context of chronic stress. This paper aims to provide clinicians with a comprehensive overview of the role of AL in patophysiology of bipolar disorder (BD) and its practical implications.

METHODS

PubMed searches were conducted on English-language articles published from 1970 to June 2011 using the search terms allostatic load, oxidative stress, staging, and bipolar disorder cross-referenced with cognitive impairment, comorbidity, mediators, prevention.

RESULTS

Progressive neural and physical dysfunction consequent to mood episodes in BD can be construed as a cumulative state of AL. The concept of AL can help to reconcile cognitive impairment and increased rates of clinical comorbidities that occur over the course of cumulative BD episodes.

CONCLUSIONS

Data on transduction of psychosocial stress into the neurobiology of mood episodes converges to the concept of AL. Mood episodes prevention would not only alleviate emotional suffering, but also arrest the cycle of AL, cognitive decline, physical morbidities and, eventually, related mortality. These objectives can be achieved by focusing on effective prophylaxis from the first stages of the disorder, providing mood-stabilizing agents and standardized psychoeducation and, potentially, addressing cognitive deficits by the means of specific medication and neuropsychological interventions.

Childhood treatment with psychotropic medication and development of comorbid medical conditions in adolescent-onset bipolar disorder

OBJECTIVE

This study aims to investigate the association between early treatment with psychotropic medications and the development of medical comorbidities in pediatric patients who develop bipolar disorder (BD).

METHODS

Data from the South Carolina Medicaid program covering all medical services and medication prescriptions between January 1996 and December 2005 were used to determine the association between childhood exposure to psychotropic medications (i.e., psychostimulants, antidepressants, and antipsychotics) and the diagnosis of select comorbid medical conditions in 1841 children and adolescents diagnosed with Diagnostic and Statistical Manual IV defined BD.

RESULTS

In separate regressions controlling for all psychotropic medications prescribed and all comorbid medical conditions diagnosed prior to the BD, hypertension and cardiovascular disorders were more likely in those prescribed second generation antipsychotics or psychostimulants, whereas obesity/overweight was more likely in those taking serotonin norepinephrine reuptake inhibitor/heterocyclic antidepressants, and asthma was more likely in those taking selective serotonin reuptake inhibitors.

CONCLUSION

Childhood cardiometabolic events appear to be systematically associated with specific classes of psychotropic medications, but no innate, developmental sequencing of cardiometabolic abnormalities was apparent before early adolescence in patients subsequently diagnosed and treated for BD.

Patterns of Axis I comorbidity in relation to age in patients with Bipolar Disorder: a cross-sectional analysis

BACKGROUND

Several data indicate that the clinical course and treatment response of Bipolar Disorder (BD) is influenced by comorbidity. However, whether differences in comorbidity patterns exist in relation to classes of age remains debated. The present study was aimed to evaluate differences in terms of cross-sectional Axis I comorbidity among young (≤30 years), adult (>30 and ≤45 years) and older adult patients with BD (>45 years).

METHODS

Study sample included 508 patients with BD, subdivided into 3 groups of age: ≤30 years (n=52), >30 and ≤45 years (n=186) and >45 years (n=270). Demographic and clinical variables, with specific emphasis on Axis I comorbidity, were compared across the different groups using chi-square tests. Furthermore, a binary logistic regression was performed.

RESULTS

Two-hundred eleven patients (41.5%) showed at least another concomitant Axis I disorder. The 3 groups were homogenous in terms of type of diagnosis (type 1 or 2 BD) and gender. However, they were different in terms of cross-sectional Axis I comorbidity (p=0.001) with a higher frequency of substance abuse (p=0.04) and Anorexia (p=0.014) in young patients, and of Obsessive Compulsive Disorder in adult patients (p=0.001). In addition, young patients showed more frequently the presence of a second comorbid Axis I condition compared to the other sub-groups (p=0.05). With regard to the type of abuse, young subjects were more frequently cannabis (p<0.001) and cocaine abusers (p<0.001) compared to the other subgroups.

LIMITATIONS

Lifetime Axis I and Axis II and cross-sectional Axis II comorbidity patterns were not analyzed.

CONCLUSIONS

Preliminary results from the present exploratory study seem to suggest different profiles of cross-sectional Axis I comorbidity and abuse in bipolar patients in relation to age. This aspect should be taken into account for the choice of pharmacological treatments and global management in clinical practice.

Prevalence and correlates of eating disorders in 875 patients with bipolar disorder

OBJECTIVE

Relatively little is known about the co-occurrence of bipolar and eating disorders. We therefore assessed the prevalence and clinical correlates of eating disorders in 875 patients with bipolar disorder.

METHOD

875 outpatients with DSM-IV bipolar I or II disorder were evaluated with structured diagnostic interviews and clinician- and self-administered questionnaires to determine bipolar and eating disorder diagnoses, other comorbid Axis I disorder diagnoses, and demographic and historical illness characteristics.

RESULTS

125 (14.3%) patients met DSM-IV criteria for at least one comorbid lifetime Axis I eating disorder, with binge eating disorder (N=77) being more common than bulimia nervosa (n=42) and anorexia nervosa (N=27). There were no significant eating disorder comorbidity differences between bipolar I and bipolar II patients. Presence of a lifetime comorbid eating disorder was associated with female gender, younger age, earlier age of onset of mood symptoms and of bipolar disorder, presentation in a mixed episode, greater number of prior mood episodes, history of rapid cycling and suicide attempts, greater mean BMI, obesity and severe obesity, and family history of depression, bipolar disorder, alcoholism, and drug abuse. When the three eating disorder groups were compared, lifetime anorexia nervosa was associated with normal weight and a lifetime anxiety disorder, lifetime bulimia nervosa was associated with overweight, and lifetime binge eating disorder was associated with obesity and severe obesity.

CONCLUSIONS

Patients with bipolar disorder, especially women, not infrequently have comorbid eating disorders, and this comorbidity is associated with an earlier age of onset and more severe course of bipolar illness.

Modeling complex genetic and environmental influences on comorbid bipolar disorder with tobacco use disorder

Background

Comorbidity of psychiatric and substance use disorders represents a significant complication in the clinical course of both disorders. Bipolar Disorder (BD) is a psychiatric disorder characterized by severe mood swings, ranging from mania to depression, and up to a 70% rate of comorbid Tobacco Use Disorder (TUD). We found epidemiological evidence consistent with a common underlying etiology for BD and TUD, as well as evidence of both genetic and environmental influences on BD and TUD. Therefore, we hypothesized a common underlying genetic etiology, interacting with nicotine exposure, influencing susceptibility to both BD and TUD.

Methods

Using meta-analysis, we compared TUD rates for BD patients and the general population. We identified candidate genes showing statistically significant, replicated, evidence of association with both BD and TUD. We assessed commonality among these candidate genes and hypothesized broader, multi-gene network influences on the comorbidity. Using Fisher Exact tests we tested our hypothesized genetic networks for association with the comorbidity, then compared the inferences drawn with those derived from the commonality assessment. Finally, we prioritized candidate SNPs for validation.

Results

We estimate risk for TUD among BD patients at 2.4 times that of the general population. We found three candidate genes associated with both BD and TUD (COMT, SLC6A3, and SLC6A4) and commonality analysis suggests that these genes interact in predisposing psychiatric and substance use disorders. We identified a 69 gene network that influences neurotransmitter signaling and shows significant over-representation of genes associated with BD and TUD, as well as genes differentially expressed with exposure to tobacco smoke. Twenty four of these genes are known drug targets.

Conclusions

This work highlights novel bioinformatics resources and demonstrates the effectiveness of using an integrated bioinformatics approach to improve our understanding of complex disease etiology. We illustrate the development and testing of hypotheses for a comorbidity predisposed by both genetic and environmental influences. Consistent with our hypothesis, the selected network models multiple interacting genetic influences on comorbid BD with TUD, as well as the environmental influence of nicotine. This network nominates candidate genes for validation and drug testing, and we offer a panel of SNPs prioritized for follow-up.