Differences in symptom expression between unipolar and bipolar spectrum depression: Results from a nationally representative sample using item response theory (IRT)

Neurocognitive risk phenotyping to predict mood symptoms in adolescence

Predicting mood disorders in adolescence is a challenge that motivates research to identify neurocognitive predictors of symptom expression and clinical profiles. This study used machine learning to test whether neurocognitive variables predicted future manic or anhedonic symptoms in two adolescent samples risk-enriched for lifetime mood disorders (Sample 1, n = 73, ages = 13-25, M [SD] = 19.22 [2.49] years, 68% lifetime mood disorder) or familial mood disorders (Sample 2, n = 154, ages = 13-21, M [SD] = 16.46 [1.95] years, 62% first-degree family history of mood disorder). Participants completed cognitive testing and functional magnetic resonance imaging at baseline, for behavioral and neural measures of reward processing and executive functioning. Next, participants completed a daily diary procedure for 8-16 weeks. Penalized mixed-effects models identified neurocognitive predictors of future mood symptoms and stress-reactive changes in mood symptoms. Results included the following. In both samples, adolescents showing ventral corticostriatal reward hyposensitivity and lower reward performance reported more severe stress-reactive anhedonia. Poorer executive functioning behavior was associated with heightened anhedonia overall in Sample 1, but lower stress-reactive anhedonia in both samples. In Sample 1, adolescents showing ventral corticostriatal reward hypersensitivity and poorer executive functioning reported more severe stress-reactive manic symptoms. Clustering analyses identified, and replicated, five neurocognitive subgroups. Adolescents characterized by neural or behavioral reward hyposensitivities together with average-to-poor executive functioning reported unipolar symptom profiles. Adolescents showing neural reward hypersensitivity together with poor behavioral executive functioning reported a bipolar symptom profile (Sample 1 only). Together, neurocognitive phenotypes may hold value for predicting symptom expression and profiles of mood pathology. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Age differences in DSM-IV borderline personality disorder symptom expression: Results from a national study using item response theory (IRT)

Limited literature suggests that there may be age-related differences in borderline personality disorder (BPD) symptom expression. The present study used item response theory (IRT) methods to examine whether there are age differences in the likelihood of endorsing DSM-IV symptoms of BPD, when equating for levels of BPD symptom severity. Data were drawn from a nationally representative survey of adults in the US (n = 34,653), the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). We found that 7 out of the 9 DSM-IV symptoms of BPD were age invariant. However, there were statistically and clinically significant differences between the oldest and youngest age groups in two BPD symptoms: oldest adult women were less likely to report suicidal/self-harm behavior than the youngest adult women across levels of BPD severity and unstable/intense interpersonal relationships discriminated BPD severity better in the youngest age group compared to the oldest age group in both genders. Overall, our findings indicate substantial age-related differences in BPD symptom expression. Mental health care providers should be alert to these two age-related differences in BPD symptom expression when making assessment and treatment decisions across adult age groups.

Examining sex differences in DSM-IV-TR narcissistic personality disorder symptom expression using Item Response Theory (IRT)

The limited published literature on the subject suggests that there may be differences in how females and males experience narcissistic personality disorder (NPD) symptoms. The aim of this study was to use methods based on item response theory to examine whether, when equating for levels of NPD symptom severity, there are sex differences in the likelihood of reporting DSM-IV-TR NPD symptoms. We conducted these analyses using a large, nationally representative sample from the USA (n=34,653), the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). There were statistically and clinically significant sex differences for 2 out of the 9 DSM-IV-TR NPD symptoms. We found that males were more likely to endorse the item 'lack of empathy' at lower levels of narcissistic personality disorder severity than females. The item 'being envious' was a better indicator of NPD severity in males than in females. There were no clinically significant sex differences on the remaining NPD symptoms. Overall, our findings indicate substantial sex differences in narcissistic personality disorder symptom expression. Although our results may reflect sex-bias in diagnostic criteria, they are consistent with recent views suggesting that narcissistic personality disorder may be underpinned by shared and sex-specific mechanisms.

Validating a two-dimensional bipolar spectrum model integrating DSM-5's mixed features specifier for Major Depressive Disorder

INTRODUCTION

The literature on DSM-5's 'Major Depressive Disorder with lifetime mixed features' (MDD-MF) is limited. This study investigated MDD-MF's potential inclusion into a bipolar spectrum.

METHODS

We recruited 287 patients with Bipolar I disorder (BD-I), BD-II, MDD-MF or 'MDD without lifetime mixed features' (MDD-noMF); most (N=280) were stabilized for at least one year on medication. Sixteen validators (clinical features, psychiatric family history, temperament, stabilizing treatment) were compared across groups and subjected to trend analyses. Two discriminant function analyses (DFA; primary and secondary), excluding or including, respectively, treatment-related predictors, explored latent dimensions maximizing between-group discrimination; mahalanobis distances between group 'centroids' were calculated.

RESULTS

Eleven validators differed significantly across groups; nine varied monotonically along a bipolar diathesis gradient with significant linear trends; two peaked at MDD-MF and displayed significant quadratic trends. In the primary DFA, apart from a classic bipolarity dimension, correlating with hospitalizations, early age at onset, lifetime psychosis and lower anxious temperament scores, on which groups ranked along a bipolar propensity gradient, a second dimension was also significant, peaking at BD-II and MDD-MF (challenging the classic bipolar ranking), which correlated with lifetime psychiatric comorbidities, suicidality, lower lifetime psychosis rates, female gender, higher cyclothymic and lower depressive temperament scores; MDD-MF was equipoised amidst BD-II and MDD-noMF. After including treatment-related predictors (secondary DFA), discrimination improved overall but BD-II and MDD-MF were closest than any other pair, suggesting similar treatment patterns for these two groups at this naturalistic setting.

CONCLUSIONS

To our knowledge, this is the first time a two-dimensional bipolar spectrum based on classic external validators is proposed, fitting the data better than a unidimensional model. Additional predictors are warranted to improve BD-II/MDD-MF discrimination.

Historical Underpinnings of Bipolar Disorder Diagnostic Criteria

Mood is the changing expression of emotion and can be described as a spectrum. The outermost ends of this spectrum highlight two states, the lowest low, melancholia, and the highest high, mania. These mood extremes have been documented repeatedly in human history, being first systematically described by Hippocrates. Nineteenth century contemporaries Falret and Baillarger described two forms of an extreme mood disorder, with the validity and accuracy of both debated. Regardless, the concept of a cycling mood disease was accepted before the end of the 19th century. Kraepelin then described “manic depressive insanity” and presented his description of a full spectrum of mood dysfunction which could be exhibited through single episodes of mania or depression or a complement of many episodes of each. It was this concept which was incorporated into the first DSM and carried out until DSM-III, in which the description of episodic mood dysfunction was used to build a diagnosis of bipolar disorder. Criticism of this approach is explored through discussion of the bipolar spectrum concept and some recent examinations of the clinical validity of these DSM diagnoses are presented. The concept of bipolar disorder in children is also explored.