A naturalistic effectiveness study of maintenance therapies for the bipolar disorders.

BACKGROUND: Treatment decision-making for individuals with bipolar disorder can be difficult. Recommendations from clinical practice guidelines can be affected by multiple methodological limitations, while pharmaco-epidemiological data suggest great variety in prescription practices across regions. Given these inconsistencies, this study aimed to provide an alternative perspective on the effectiveness of common bipolar disorder maintenance treatments through considering naturalistic data. METHODS: A total of 246 individuals with bipolar disorder (84 bipolar I [BP-I], 162 bipolar II [BP-II]) were recruited through clinics and/or websites. All were euthymic and had trialled at least one mood stabiliser. They completed an online survey containing questions on demographics, clinical variables, symptomatology, and the effectiveness/side effect profiles of any mood stabilisers (MSTs) or atypical antipsychotics (AAPs) that they have taken. RESULTS: Lithium and lamotrigine were the most commonly prescribed MSTs and the most effective at mood stabilisation. Lithium and lamotrigine appeared marginally more effective for BP-I and BP-II respectively, however, only the latter difference was statistically significant. Furthermore, lamotrigine had the more favourable side effect profile. Amongst the AAPs, quetiapine and olanzapine were the most commonly prescribed, but they were negligibly superior to other AAPs. CONCLUSION: This study clearly established a preference for lamotrigine in the maintenance treatment of BP-II. While the literature consistently emphasises the primacy of lithium in bipolar disorder treatment, its side effect profile as observed in this study remains a concern. Future research considering moderators of treatment response and concomitant medications could help to identify further nuances to consider for treatment decision-making.

An observer-rated strategy for differentiating schizophrenic and manic states in inpatient settings.

OBJECTIVES: Differentiating schizophrenia from mania in acutely psychotic patients can be difficult, but is important in determining immediate and subsequent management. Such differentiation is generally addressed by clinical interviews, but an observational approach may assist. This paper therefore describes the development of a relevant observational measure. METHODS: We developed a provisional list of 49 items (weighting features with suggested specificity to schizophrenia and mania) for independent completion by two nurses and judged its ability to predict diagnosis provided by consultant psychiatrists. RESULTS: Eighty-seven psychotic patients were recruited, and 173 completed data sets were analysed. We refined the item set to two sets of 10 items that best-differentiated schizophrenia from mania and vice versa. Optimal differentiation was achieved with a score of at least 7 on both the schizophrenia and mania item sets. Difference scores (i.e. schizophrenia items affirmed minus mania items affirmed) were also generated, with a difference score of +1 (i.e. one or more schizophrenia items being affirmed than mania items) showing optimal differentiation (sensitivity 0.67, specificity 0.82) between the two conditions. Evaluating all potential difference scores, we demonstrated that, as difference scores increased, diagnostic accuracy in identifying each condition was very high. CONCLUSION: Analyses allow the properties of an observational measure (the 20-item Sydney Psychosis Observation Tool) to be described. While a single cut-off difference score was derived with acceptable discriminatory ability, we also established the capacity of varying difference scores to assign both schizophrenia and mania diagnoses with high accuracy.

A chat about bipolar disorder.

OBJECTIVES: This study aimed to assess the capabilities of ChatGPT (Chat Generative Pre-Trained Transformer) in generating informative content related to bipolar disorders. The objectives were to evaluate its ability to provide accurate information on symptoms, classification, causes, and management of bipolar disorder and to explore its creativity in generating topic-related songs. METHODS: ChatGPT3 was used for the study, and a series of clinically relevant questions were asked to test its knowledge and creativity. Questions ranged from common symptom descriptions to more artistic requests for songs related to bipolar disorder. RESULTS: ChatGPT demonstrated the capacity to provide basic and informative material on bipolar disorders, including descriptions of symptoms, classification types, causes, and treatment options. It also showed creativity in generating songs that capture the nuances of bipolar symptoms, both during high and low states. CONCLUSIONS: While ChatGPT3 can offer superficial information on psychiatric topics like bipolar disorder, its inability to provide accurate and up-to-date references limits its utility for creating a comprehensive review article for scientific journals. However, it may be helpful in generating educational material and assisting in component tasks for those with bipolar disorder or other psychiatric conditions. As newer versions of AI models are continually developed, their capabilities in producing more accurate and advanced content will need further evaluation.

Modelling self-diagnosed burnout as a categorical syndrome.

OBJECTIVE: There is currently little consensus as to how burnout is best defined and measured, and whether the syndrome should be afforded clinical status. The latter issue would be advanced by determining whether burnout is a singular dimensional construct varying only by severity (and with some level of severity perhaps indicating clinical status), or whether a categorical model is superior, presumably reflecting differing 'sub-clinical' versus 'clinical' or 'burning out' vs 'burnt out' sub-groups. This study sought to determine whether self-diagnosed burnout was best modelled dimensionally or categorically. METHODS: We recently developed a new measure of burnout which includes symptoms of exhaustion, cognitive impairment, social withdrawal, insularity, and other psychological symptoms. Mixture modelling was utilised to determine if scores from 622 participants on the measure were best modelled dimensionally or categorically. RESULTS: A categorical model was supported, with the suggestion of a sub-syndromal class and, after excluding such putative members of that class, two other classes. Analyses indicated that the latter bimodal pattern was not likely related to current working status or differences in depression symptomatology between participants, but reflected subsets of participants with and without a previous diagnosis of a mental health condition. CONCLUSION: Findings indicated that sub-categories of self-identified burnout experienced by the lay population may exist. A previous diagnosis of a mental illness from a mental health professional, and therefore potentially a psychological vulnerability factor, was the most likely determinant of the bimodal data, a finding which has theoretical implications relating to how best to model burnout.

The AREDOC project and its implications for the definition and measurement of the bipolar disorders: A summary report.

OBJECTIVES: Judging that the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria for defining mania/hypomania (and thus bipolar I/II disorders, respectively) would benefit from review, we formed an expert taskforce to derive modified criteria for consideration. The aim of this paper is to summarise the component stages and detail the final recommended criteria. METHODS: We first sought taskforce members' views on the Diagnostic and Statistical Manual of Mental Disorders criteria and how they might be modified. Next, members recruited patients with a bipolar I or II disorder, and who were asked to judge new definitional options and complete a symptom checklist to determine the most differentiating items. The latter task was also completed by a small comparison group of unipolar depressed patients to determine the mood state items that best differentiate unipolar from bipolar subjects. Subsequent reports overviewed analyses arguing for bipolar I and II as being categorically distinct and generated empirically derived diagnostic criteria. RESULTS: Alternatives to all the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria were generated. Modifications included recognising that impairment is not a necessary criterion, removing hospitalisation as automatically assigning bipolar I status, adding an irritable/angry symptom construct to the symptom list, deleting a mandatory duration period for manic/hypomanic episodes, and requiring a greater number of affirmed symptoms for a bipolar diagnosis to manage the risk of overdiagnosis. Granular symptom criteria were identified by analyses and constructed to assist clinician assessment. A potential bipolar screening measure was developed with analyses showing that it could clearly distinguish bipolar versus unipolar status, whether symptom items were assigned as having equal status or weighted by their quantified diagnostic contribution. CONCLUSION: While requiring further validation, we suggest that the revised criteria overcome several current Diagnostic and Statistical Manual of Mental Disorders (5th ed.) limitations to defining and differentiating the two bipolar sub-types, while still respecting and preserving the Diagnostic and Statistical Manual of Mental Disorders template. It will be necessary to determine whether the bipolar screening measure has superiority to currently accepted measures.

Sugar consumption and behavioural inhibition in the rat.

The metabolic effects of sugary drinks have been extensively studied, whereas the effects on psychological processes have received relatively limited attention. Several studies have found that high-sugar diets can produce impaired performance by rats on tests assessing spatial learning and memory. In contrast, despite claims that weakened inhibitory control underlies many sugar-induced deficits, evidence supporting this proposal has been limited. The aim of the present study was to assess the impact of high-sugar diets on response inhibition, as measured by rats' performance on a differential reinforcement of low rates schedule (DRL) in Experiments 1 and 2 and on a Pavlovian discrimination reversal task in Experiment 3. In all three experiments a 30-day diet stage, in which Sugar groups were given unrestricted access to 10% sucrose solution and Control groups had access to water only, was followed by behavioural tests. In Experiment 1 the Sugar group performed poorly on a spatial memory task, but no difference was detected between the performances of the two groups in the DRL test. In Experiment 2 longer DRL training was given and post-diet performance was assessed both before and after access to sugar was withdrawn. Null results were obtained under both conditions. In Experiment 3 rats' performance on a discrimination learned prior to the diet intervention was not affected by the high-sugar diet, but neither was performance once the discrimination was reversed. The implications of these results for understanding of sugar-induced psychological deficits are discussed.

The utility of daily mood ratings in clinical trials of patients with bipolar II disorder.

OBJECTIVE: To demonstrate that there can be distinctive differences in information generated by standard interval measures as against using daily monitoring for evaluating progress in those with a bipolar disorder. METHOD: We undertook a 20-week study of individuals with a bipolar II disorder randomly assigned to receive either lamotrigine or lithium. Patients were rated on standard measures of depression and hypomania at monthly intervals, and they also completed a daily rating measure of their mood swings. We sought to demonstrate the potential for differing interpretations that emerge from these measurement strategies. RESULTS: We graphed data for one subject who showed distinct improvement but demonstrated distinctly differing trajectories provided by monthly and daily data. In a second analysis, we considered sets of those who were judged as improving distinctly with lithium or lamotrigine to determine whether the drugs differed in speed of action, and again observed differing patterns between monthly and daily rating measures. CONCLUSIONS: A daily rating strategy appeared to provide additional and differing data compared to standard monthly measures. We therefore argue for the inclusion of daily mood ratings in clinical trials evaluating mood stabilisers and their use by clinicians in managing those with a bipolar II disorder.

Does theta burst stimulation have differential benefit for those with melancholic or non-melancholic depression?

BACKGROUND: To determine if theta burst stimulation (TBS) is of preferential benefit to those with melancholic or non-melancholic depression as an adjunctive treatment for treatment resistant depression (TRD). METHODS: Fifty-two patients receiving TBS at a private psychiatric hospital participated in a naturalistic study. Four diagnostic strategies were used to assign melancholic versus non-melancholic depression subtype status. Depression symptoms were assessed at baseline, mid-treatment, and end of treatment using the Montgomery-Ǻsberg Depression Rating Scale - Self-Assessment (MADRS-S). Forty-one participants also completed the MADR-S at a six-week follow-up assessment. RESULTS: We quantified poor correlations between the four study measures of melancholia; a finding suggesting that valid measurement of melancholia is likely to remain problematic. TBS led to significant reductions in depression symptoms from baseline to end of treatment, with this effect maintained at follow up. Response rates for the whole sample were 61.5 % at end of treatment and 53.7 % at follow-up, while remission rates were 34.6 % at end of treatment and 31.7 % at follow-up. Improvement rates as well as responder and remission rates were comparable for the melancholic and non-melancholic groups, irrespective of the diagnostic strategy used. LIMITATIONS: The study was naturalistic (i.e., there being no control group, and concomitant medication changes were allowed), depression severity was assessed only by use of self-report measures, and the sample size was relatively small. CONCLUSION: TBS appears to be non-specific, in that we failed to quantify any statistically significant differential benefit for those with melancholic compared to those with non-melancholic depression.

Cognitive bias modification of interpretations for anxiety and depression in children and adolescents: A meta-analysis.

Background: Evidence suggests that cognitive bias modification of interpretations (CBM-I) is effective in modifying interpretation biases and has a small effect on reducing anxiety in children and adolescents. However, most evidence to date is based on studies which report anxiety or general distress using ad-hoc Likert-type or Visual Analogue Scales, which are useful but do not reliably index symptoms of clinical importance. This meta-analysis aimed to establish the effects of CBM-I for children and adolescents on both anxiety and depression using psychometrically validated symptom measures, as well as state negative affect and negative and positive interpretation bias. Methods: We identified studies through a systematic search. To be eligible for inclusion, studies needed to target interpretation biases, not combine CBM-I with another intervention, randomly allocate participants to CBM-I or a control condition, assess a mental health outcome (i.e., anxiety or depression symptoms using validated measures or state measures of negative affect) and/or interpretation bias and have a mean age less than 18 years. Results: We identified 36 studies for inclusion in the meta-analysis. CBM-I had a small and non-significant unadjusted effect on anxiety symptoms (g = 0.16), no effect on depression symptoms (g = -0.03), and small and non-significant unadjusted effects on state negative affect both at post-training (g = 0.16) and following a stressor task (g = 0.23). In line with previous findings, CBM-I had moderate to large unadjusted effects on negative and positive interpretations (g = 0.78 and g = 0.52). No significant moderators were identified. Conclusions: CBM-I is effective at modifying interpretation bias, however there were no effects on mental health outcomes. The substantial variability across studies and paucity of studies using validated symptom measures highlight the need to establish randomized controlled trial protocols that evaluate CBM-I in clinical youth samples to determine its future as a clinical intervention.

Differentiating melancholic and non-melancholic depression via biological markers: A review.

OBJECTIVES: Melancholia is a severe form of depression that is typified by greater genetic and biological influence, distinct symptomatology, and preferential response to physical treatment. This paper sought to broadly overview potential biomarkers of melancholia to benefit differential diagnosis, clinical responses and treatment outcomes. Given nuances in distinguishing melancholia as its own condition from other depressive disorder, we emphasised studies directly comparing melancholic to non-melancholic depression. METHODS: A comprehensive literature search was conducted. Key studies were identified and summarised qualitatively. RESULTS: 105 studies in total were identified. These studies covered a wide variety of biomarkers, and largely fell into three domains: endocrinological (especially cortisol levels, particularly in response to the dexamethasone suppression test), neurological, and immunological (particularly inflammatory markers). Less extensive evidence also exists for metabolic, genetic, and cardiovascular markers. CONCLUSIONS: Definitive conclusions were predominantly limited due to substantial heterogeneity in how included studies defined melancholia. Furthermore, this heterogeneity could be responsible for the between- and within-group variability observed in the candidate biomarkers that were examined. Therefore, clarifying these definitional parameters may help identify underlying patterns in biomarker expression to improve diagnostic and therapeutic precision for the depressive disorders.

Phase-based concerns of caregivers for individuals with a bipolar disorder.

BACKGROUND: Caregivers have a key role in providing social and practical support for individuals with bipolar disorder. As such, their perspectives are uniquely important when collaborative decisions are made on management priorities and potential treatment options. AIMS: This study aims to identify common concerns that caregivers have in the management of an individual with a bipolar disorder. METHOD: 111 caregivers were recruited from online advertisements and social media support groups. They completed a questionnaire that obtained demographic and clinical feature details, in addition to whether a series of generic and phase-specific (i.e. depressive or hypo/manic) management concerns reflected their experiences of caregiving. RESULTS: Concerns about work capacity and family impacts were almost ubiquitous, as were general feelings of ineffectiveness and irritation. Depressive phases were more likely to elicit fears of suicide by caregivers, while during hypo/manic phases caregivers were more likely to be angered, have concerns for their own safety, call emergency services or to take safety precautions. There were no differences between bipolar subtypes with regards to concerns during depressive phases, but concerns around safety, reputational damage and risky behaviours were more likely in relation to those experiencing bipolar I manic phases compared to bipolar II hypomanic phases. CONCLUSIONS: The concerns identified by caregivers in this paper are consistent with clinical expectations, with concerns regarding insularity and externalisation being prominent for depression and hypo/mania respectively. Not all of these caregivers' concerns would necessarily be communicated in a healthcare setting, highlighting the need for an embracive approach to improve management outcomes. Additionally, caregivers' emphasis on their distinctive altruistic concerns highlights their commitment to care despite the challenges, and thus further highlights the potential for clinicians to implement a more proactive role for them in patient care.

Estimated Prevalence of Depressive Disorders in Children From 2004 to 2019: A Systematic Review and Meta-Analysis.

Importance: Depression during childhood (ie, age <13 years) poses a major health burden. Recent changes in environmental and lifestyle factors may increase children's risk of mental health problems. This has been reported for anxiety disorders, but it is unclear whether this occurs for depressive disorders. Objective: To provide prevalence estimates for the depressive disorders (ie, major depressive disorder [MDD], dysthymia, disruptive mood dysregulation disorder [DMDD], and overall) in children, and whether they have changed over time. Data Sources: The MEDLINE, PsycINFO, Embase, Scopus, and Web of Science databases were searched using terms related to depressive disorders, children, and prevalence. This was supplemented by a systematic gray literature search. Study Selection: Studies were required to provide population prevalence estimates of depressive disorder diagnoses (according to an established taxonomy and standardized interviews) for children younger than 13 years, information about participants' year of birth, and be published in English. Data Extraction and Synthesis: Data extraction was compliant with the Meta-Analysis of Observational Studies in Epidemiology guidelines. A total of 12 985 nonduplicate records were retrieved, and 154 full texts were reviewed. Data were analyzed from 2004 (the upper limit of a previous review) to May 27, 2023. Multiple proportional random-effects meta-analytic and mixed-effects meta-regression models were fit. Main Outcomes and Measures: Pooled prevalence rates of depressive disorders, prevalence rate differences between males vs females and high-income countries (HICs) vs low-and middle-income countries (LMICs), and moderating effects of time or birth cohort. Results: A total of 41 studies were found to meet the inclusion criteria. Pooled prevalence estimates were obtained for 1.07% (95% CI, 0.62%-1.63%) for depressive disorders overall, 0.71% (95% CI, 0.48%-0.99%) for MDD, 0.30% (95% CI, 0.08%-0.62%) for dysthymia, and 1.60% (95% CI, 0.28%-3.90%) for DMDD. The meta-regressions found no significant evidence of an association with birth cohort, and prevalence rates did not differ significantly between males and females or between HICs and LMICs. There was a low risk of bias overall, except for DMDD, which was hindered by a lack of studies. Conclusions and Relevance: In this systematic review and meta-analysis, depression in children was uncommon and did not increase substantially between 2004 and 2019. Future epidemiologic studies using standardized interviews will be necessary to determine whether this trend will continue into and beyond the COVID-19 pandemic.

Proband-mediated interventions to increase disclosure of genetic risk in families with a BRCA or Lynch syndrome condition: a systematic review.

Interventions to assist family communication about inherited cancer risk have the potential to improve family cancer outcomes. This review aimed to evaluate the efficacy of proband-mediated interventions employed within genetics clinics to increase disclosure of genetic risk to at-risk relatives. MEDLINE, Embase, CINAHL, PubMed and PsycINFO were searched for publications between 1990-2020. The quality of studies was assessed. From 5605 records reviewed, 9 studies (4 randomised control trials and 5 cohort studies) were included involving families with BRCA1, BRCA2 and Lynch syndrome. Intervention delivery modes included genetic counselling with additional telephone or in-person follow-up, letters, videos, and decision aids. The percentages of at-risk relatives informed by the proband about their risk ranged from 54.0% to 95.5% in the intervention or family-mediated comparison group. Of those who were informed, 24.4-60.0% contacted a genetics clinic and 22.8-76.2% had genetic testing after they were counselled at a genetics clinic. Significant differences between intervention and control group were reported on all three outcomes by one study, and with relatives contacting a genetics clinic by another study. The studies suggest but do not conclusively show, that tailored genetic counselling with additional follow-up can increase both the proportion of informed relatives and relatives who contact the genetics clinic. With the increase in germline testing, interventions are required to consider the family communication process and address post-disclosure variables (e.g., relative's perceptions, emotional reactions) through engagement with probands and relatives to maximise the public health benefit of identifying inherited cancer risk in families.

Why might bipolar disorder and borderline personality disorder be bonded?

The prevalence of comorbid bipolar disorder (BD) and borderline personality disorder (BPD) is distinctly higher in community samples than would be expected if the two conditions are independent. While there have been multiple explanations suggested for their interdependence, no clear model has been established. This paper reviews a broader set of explanations than considered previously, where relevant prevalence studies of the conditions are reported, previous explanations overviewed, and additional potential linkage causes are considered. It was found that there is unlikely to be any single determinant of the comorbid presence of BD and BPD. The most likely candidates are the artefactual impact of transdiagnostic features, with true comorbid status reflecting both pleiotropic genetic influences and environmental factors. Measurement errors in diagnostic assignment emerging from transdiagnostic features are likely to have clouded previous studies and therefore the interpretations. Comorbid BD/BPD is likely to be distinctly more common than estimated by clinicians, and clarification of the reasons why this is may well assist clinical management.

Medical treatment decision-making in rural cancer patients: A qualitative systematic review and meta-synthesis.

OBJECTIVE: Rural cancer patients have unique care needs which may impact upon treatment decision-making. Our aim was to conduct a qualitative systematic review and meta-synthesis to understand their perspectives and experiences of making treatment decisions. METHODS: A systematic search of MEDLINE, PsycINFO, CINAHL and RURAL was conducted for qualitative studies in rural cancer patients regarding treatment decision-making. Articles were screened for relevance, and data from the included articles were extracted and analysed using meta-thematic synthesis. RESULTS: Twelve studies were included, with 4 themes and 9 subthemes identified. Many studies reported patients were not given a choice regarding their treatment. Choice, if given, was influenced by personal factors such as finances, proximity to social supports, convenience, and their personal values. Patients were also influenced by the opinions of others and cultural norms. Finally, it was reported that patients made choices in the context of seeking the best possible medical care and the patient-clinician relationship. CONCLUSIONS: In the rural context, there are universal and unique factors that influence the treatment decisions of cancer patients. PRACTICAL IMPLICATIONS: Our findings are an important consideration for clinicians when engaging in shared decision-making, as well as for policymakers, to understand and accommodate the unique rural perspective.

A new machine learning-derived screening measure for differentiating bipolar from unipolar mood disorders.

BACKGROUND: While there are several accepted screening measures for identifying those with a bipolar disorder, variations in overall classification rates argue for the pursuit of a more discriminating measure. Extant measures, as well as the DSM-5, rate each diagnostic criterion as having equivalent weighting values; an approach which may compromise diagnostic assignment if symptoms vary considerably in their diagnostic sensitivity. We therefore sought to develop a new measure and examine whether a weighted rating scale was superior to one assigning equivalent weightings to each item. METHODS: An international sample of 165 bipolar patients and a comparison sample of 29 unipolar patients completed a measure assessing 96 putative manic/hypomanic symptoms. A previous machine learning analysis had identified the twenty most discriminating items. In this study, analysis was undertaken involving only the ten most discriminating items. RESULTS: Whether items were scored as each having equivalent value or as weighted by their machine learning-generated values, classificatory accuracy was extremely high (in the order of 96%). Analyses also identified optimal cut-off scores. High classificatory accuracy was also obtained when scores for separate bipolar I and bipolar II groups were compared with scores from the unipolar group. LIMITATIONS: The sample consisted of comparatively few unipolar patients. CONCLUSIONS: The ten-item set allows a new measure for researchers to evaluate, while the items should assist clinician assessment as to whether a patient has a bipolar or unipolar mood disorder.

Melancholia defined with the precision of a machine.

BACKGROUND: The status of melancholia as a categorical or dimensional condition remains unclear, and no measure of melancholia has achieved definitive status. This study aimed to use a machine learning approach to assess whether a pre-established cut-off score on the Sydney Melancholia Prototype Index (SMPI) provided clear differentiation of melancholic/non-melancholic depression, and to identify the items making the most distinct contribution. METHODS: We analysed amalgamated data sets of 1513 clinically depressed patients assessed via the clinician-rated version of the SMPI (SMPI-CR). We also evaluated the self-report version of the SMPI (SMPI-SR) in a combined clinical/community sample of 2025 depressed patients and senior high school students. Rule ensembles were derived in which the outcome measure was the presence/absence of melancholia (defined as scoring at or above a SMPI cut-off score that had been established in previous studies) and the predictive variables were the individual SMPI items. RESULTS: The pre-established SMPI cut-off score was confirmed as differentiating melancholic/non-melancholic with near perfect accuracy for the SMPI-CR, and with very high accuracy for the SMPI-SR. The relative importance of all SMPI items was quantified. LIMITATIONS: It is difficult to validate SMPI-assigned diagnoses due to the lack of any similar measures. CONCLUSIONS: The SMPI-CR was confirmed to be a highly precise instrument for differentiating melancholic and non-melancholic depression. Its use will advance clinical decision making and studies evaluating causes, mechanisms and treatments for the two depressive sub-types, as well as assist clarification as to whether melancholia is categorically or dimensionally distinct from non-melancholic depression.

Differentiation of bipolar disorder versus borderline personality disorder: A machine learning approach.

BACKGROUND: Differentiation of bipolar disorder (BP) from borderline personality disorder (BPD) is a common diagnostic dilemma. We undertook a machine learning (ML) approach to distinguish the conditions. METHODS: Participants meeting DSM criteria for BP or BPD were compared on measures examining cognitive and behavioral BPD constructs, emotion regulation strategies, and parental behaviors during childhood. Two analyses used continuous and dichotomised data, with ML-allocated diagnoses compared to DSM. RESULTS: 82 participants met DSM criteria for BP and 52 for BPD. Accuracy of ML classification was 84.1% - 87.8% for BP, 50% - 57.7% for BPD, with overall accuracy of 73.1% - 73.9%. Importance of items differed between the analyses with the overall most important items including identity difficulties, relationship problems, female gender, feeling suicidal after a relationship breakdown and age. LIMITATIONS: Participants were volunteers, preponderance of bipolar II (BP II) participants, comorbidity of BP and BPD not examined, and small BPD sample contributed to the relatively low classification accuracies for this group CONCLUSIONS: Study findings may assist distinguishing BP and BPD based on differences in cognitive and behavioral domains, emotion regulation strategies and parental behaviors. Future studies using larger datasets could further improve predictive accuracy and assist in differential diagnosis.