1,721,031 research outputs found
Neurobiology of bipolar subtypes: multivariate structural neuroimaging approaches
Full text linkDebates persist regarding the optimal approach to manage the heterogeneity behind the broad concept of bipolar disorder (BD), with the precise neurobiological mechanisms differentiating the main BD subtypes, BD type I (BD-I) and BD type II (BD-II), remain a subject of ongoing research. The exploration of structural brain networks, coupled with an in-depth examination of the interplay between network covariance patterns, clinical, psychological functioning, and affective temperaments, has not been systematically investigated across the BD subtypes. Thirty BD-I, 30 BD-II, and 45 age- and sex-matched healthy controls (HC) underwent an MRI scan. For the neuropsychological measures, the Tower of Hanoi to investigate executive functions, the Facial Emotion Recognition (FER) task for emotional processing, and the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Scale to investigate affective temperaments were administered to participants. Clinical assessment was conducted, and a detailed history of mood disorders and pharmacological treatments were recorded. Gray matter volume (GMV) and white matter were estimated using voxel-based morphometry and fractional anisotropy (FA) analysis, respectively. Source-based morphometry (SBM) was performed to extract structural covariation patterns of GMV and white matter FA. GMV, FA values, and SBM components associated with morphometric and FA differences were compared across BD-I, BD-II, and HC. GMV of the cortico-limbic regions implicated in emotional processing was estimated and their relationship with FER performance was investigated using network analysis. To explore the relationships between structural changes, clinical data, executive and emotional processing measures, Pearson's or Spearman's correlation were performed. BD-I exhibited reduced GMV in the temporo-insular-parieto-occipital cortex and in the cerebellum compared with HC, while no significant differences between BD-II and HC nor between BD subtypes emerged. An SBM component encompassing the prefrontal-temporal-occipital network displayed significantly lower GMV in BD-I compared to HC, but not between the other groups. The reduced structural network covariance in BD-I was associated with the number of previous manic episodes and with worse executive performance. Compared with BD-II, BD-I showed a general impairment in FER performance, which was correlated with temporal-occipital GMV loss.
BD-I displayed the poorest sadness-related FER performance relative to the other groups. In BD-I, sadness-related FER performance was negatively correlated with illness duration and the number of previous manic episodes and positively associated with global functioning. Overall structure of the network of BD subtypes was altered compared with HC, with BD-I showing a reduced GMV interrelationship in the frontal–insular–occipital regions and greater edge strength between sadness-related FER performance and amygdala GMV relative to HC. Compared with HC, BD-I and BD-II showed significant FA reduction encompassing the corpus callosum, the genu of the corpus callosum, the cingulum and parahippocampal circumvolution bilaterally, and parieto-occipital regions bilaterally. BD-II had two clusters of significantly greater FA located in the genu of the corpus callosum and in the right parahippocampal circumvolution relative to BD-I. In BD-I, the SBM component of lower cingolo-callosal-parahippocampal FA covariance (IC1 loadings) had a significant positive correlation with the irritable temperament score, which was significantly higher in BD-I than HC. Using multivariate approaches, incorporating clinical, behavioral, and neuroimaging data analysis, we observed several structural and behavioral differences between BD-I and BD-II that confirm the clinical and nosological differentiation between the main BD subtypes. The identified networks can be targeted for more accurate prognosis prediction and tailored interventions
Effects of Treatment of Acute Major Depressive Episodes in Bipolar I Versus Bipolar II Disorders With Quetiapine
No full textBackground Several second-generation antipsychotic drugs (SGAs) have evidence of benefit for acute major depressive episodes in bipolar disorder (BD) patients. However, their comparative efficacy in types I vs II BD (BD1 vs BD2) remains uncertain. Methods We carried out a systematic literature search for randomized, double-blinded, controlled treatment trials for acute major depressive episodes involving head-to-head comparisons of BD1 versus BD2 subjects, followed by meta-analyses and meta-regression modeling. Results Seven reports met out inclusion criteria, yielding 22 comparisons of SGA versus placebo averaging 8.3 weeks in duration. All trials involved quetiapine, which was much more effective than placebo (pooled standardized mean difference [SMD] = 1.76 [95% confidence interval, 1.40-2.12], P BD2) to be the only factor significantly associated with the meta-analytic outcome. Conclusions Although data are limited, depressed BD1 patients may respond somewhat better to quetiapine than BD2. Additional head-to-head diagnostic comparisons are needed with other SGAs, as well as evaluation of monotherapy versus various combinations that include SGAs in both short- and long-term use
Whole-brain structural and functional neuroimaging of individuals who attempted suicide and people who did not: A systematic review and exploratory coordinate-based meta-analysis
Full text linkSuicide is the cause of death of approximately 800,000 people a year. Despite the relevance of this behaviour, risk assessment tools rely on clinician experience and subjective ratings. Given that previous suicide attempts are the single strongest predictors of future attempts, we designed a systematic review and coordinate-based meta-analysis to demonstrate whether neuroimaging features can help distinguish individuals who attempted suicide from subjects who did not. Out of 5,659 publications from PubMed, Scopus, and Web of Science, we summarised 102 experiments and meta-analysed 23 of them. A cluster in the right superior temporal gyrus, a region implicated in emotional processing, might be functionally hyperactive in individuals who attempted suicide. No statistically significant differences in brain morphometry were evidenced. Furthermore, we used JuSpace to show that this cluster is enriched in 5-HT1A heteroreceptors in the general population. This exploratory meta-analysis provides a putative neural substrate linked to previous suicide attempts. Heterogeneity in the analytical techniques and weak or absent power analysis of the studies included in this review currently limit the applicability of the findings, the replication of which should be prioritised
Factors associated with onset-age in major affective disorders
No full textBackground: Research findings on factors associated with onset-age (OA) with bipolar (BD) and major depressive disorders (MDD) have been inconsistent, but often indicate greater morbidity following early OA. Methods: We considered factors associated with OA in 1033 carefully evaluated, systematically followed mood disorder subjects with DSM-5 BD (n = 505) or MDD (n = 528), comparing rates of descriptive and clinical characteristics following early (age <18), intermediate (18–40), or later onset (≥40 years), as well as regressing selected measures versus OA. Exposure time (years ill) was matched among these subgroups. Results: As hypothesized, many features were associated with early OA: familial psychiatric illness, including BD, greater maternal age, early sexual abuse, nondepressive first episodes, co-occurring ADHD, suicide attempts and violent suicidal behavior, abuse of alcohol or drugs, smoking, and unemployment. Other features increased consistently with later OA: %-time-depressed (in BD and MDD, women and men), as well as depressions/year and intake ratings of depression, educational levels, co-occurring medical disorders, rates of marriage and number of children. Conclusions: OA averaged 7.5 years earlier in BD versus MDD (30.7 vs. 38.2). Some OA-associated measures may reflect maturation. Associations with family history and suicidal risk with earlier OA were expected; increases of time-depressed in both BD and MDD with later OA were not. We conclude that associations of OA with later morbidity are complex and not unidirectional but may be clinically useful
Characteristics of rapid cycling in 1261 bipolar disorder patients
Full text linkBackground: Rapid-cycling (RC; ≥ 4 episodes/year) in bipolar disorder (BD) has been recognized since the 1970s and associated with inferior treatment response. However, associations of single years of RC with overall cycling rate, long-term morbidity, and diagnostic subtypes are not clear. Results: We compared descriptive and clinical characteristics in 1261 BD patients with/without RC, based on history and prospective follow-up for several years. RC in any previous year was identified in 9.36% of BD subjects (3.74% in BD1, 15.2% BD2), and somewhat more among women than men. RC-BD subjects had 3.21-fold greater average prospective annual rates of recurrence but not hospitalizations, had less difference in %-time-ill, received more mood-stabilizing treatments, and had greater suicidal risk, lacked familial psychiatric illnesses, had more cyclothymic temperament, were more likely to be married, had more siblings and children, experienced early sexual abuse, but were less likely to abuse drugs (not alcohol) or smoke. In multivariable regression modeling, older age, mood-switching with antidepressants, and BD2 > BD1 diagnosis, as well as more episodes/year were independently associated with RC. Notably, prospective mean recurrence rates were below 4/year in 79.5% of previously RC patients, and below 2/year in 48.1%. Conclusions: Lifetime risk of RC in BD was 9.36%, more likely in women, with older age, and in BD2 > BD1. With RC, recurrence rates were much higher, especially for depression with less effect on %-time ill, suggesting shorter episodes. Variable associations with unfavorable outcomes and prospective recurrence rates well below 4/year in most previously RC patients indicate that RC was not a sustained characteristic and probably was associated with use of antidepressants
Differences between bipolar disorder types 1 and 2 support the DSM two-syndrome concept
Full text linkObjective: To compare characteristics of bipolar disorder patients diagnosed as DSM-5 types I (BD-1) vs. II (BD-2). Methods: We compared descriptive, psychopathological, and treatment characteristics in a sample of 1377 consenting, closely and repeatedly evaluated adult BD patient-subjects from a specialty clinic, using bivariate methods and logistic multivariable modeling. Results: Factors found more among BD-2 > BD-1 cases included: [a] descriptors (more familial affective disorder, older at onset, diagnosis and first-treatment, more education, employment and higher socioeconomic status, more marriage and children, and less obesity); [b] morbidity (more general medical diagnoses, less drug abuse and smoking, more initial depression and less [hypo]mania or psychosis, longer episodes, higher intake depression and anxiety ratings, less mood-switching with antidepressants, less seasonal mood-change, greater %-time depressed and less [hypo]manic, fewer hospitalizations, more depression-predominant polarity, DMI > MDI course-pattern, and less violent suicidal behavior); [c] specific item-scores with initial HDRS21 (higher scores for depression, guilt, suicidality, insomnia, anxiety, agitation, gastrointestinal symptoms, hypochondriasis and weight-loss, with less psychomotor retardation, depersonalization, or paranoia); and [d] treatment (less use of lithium or antipsychotics, more antidepressant and benzodiazepine treatment). Conclusions: BD-2 was characterized by more prominent and longer depressions with some hypomania and mixed-features but not mania and rarely psychosis. BD-2 subjects had higher socioeconomic and functional status but also high levels of long-term morbidity and suicidal risk. Accordingly, BD-2 is dissimilar to, but not necessarily less severe than BD-1, consistent with being distinct syndromes
Suicidal risk and protective factors in major affective disorders: A prospective cohort study of 4307 participants
Full text linkBackground: Suicidal behavior is strongly associated with major affective disorders, but there is a need to quantify and compare specific risk and protective factors in bipolar disorder (BD) and major depressive disorder (MDD). Methods: In 4307 extensively evaluated major affective-disorder participants with BD (n = 1425) or MDD (n = 2882) diagnosed by current international criteria, we compared characteristics among those with versus without suicidal acts from illness-onset through 8.24 years of follow-up. Results: Suicidal acts were identified in 11.4 % of participants; 25.9 % were violent and 6.92 % (0.79 % of all participants) were fatal. Associated risk factors included: diagnosis (BD > MDD), manic/psychotic features in first-episodes, family history of suicide or BD, separation/divorce, early abuse, young at illness-onset, female sex with BD, substance abuse, higher irritable, cyclothymic or dysthymic temperament ratings, greater long-term morbidity, and lower intake functional ratings. Protective factors included marriage, co-occurring anxiety disorder, higher ratings of hyperthymic temperament and depressive first episodes. Based on multivariable logistic regression, five factors remained significantly and independently associated with suicidal acts: BD diagnosis, more time depressed during prospective follow-up, younger at onset, lower functional status at intake, and women > men with BD. Limitations: Reported findings may or may not apply consistently in other cultures and locations. Conclusions: Suicidal acts including violent acts and suicides were more prevalent with BD than MDD. Of identified risk (n = 31) and protective factors (n = 4), several differed with diagnosis. Their clinical recognition should contribute to improved prediction and prevention of suicide in major affective disorders
Relationships of affective temperament ratings to diagnosis and morbidity measures in major affective disorders
Full text linkBackground Ratings of affective temperament types show promise in helping to differentiate diagnostic groups among major affective disorders as well as to predict associations with important aspects of morbidity including suicidal risk. Methods The Temperament Evaluation of Memphis, Pisa, Paris, and San Diego auto-rating (TEMPS-A) questionnaire was completed by 858 unselected, consecutive, consenting adults diagnosed with a DSM-5 major affective disorder (173 bipolar-1 [BD-1]), 250 BD-2, 435 major depressive disorder [MDD]) to score for anxious (anx), cyclothymic (cyc), dysthymic (dys), hyperthymic (hyp), and irritable (irr) affective temperaments. We tested their associations with diagnosis and selected clinical factors, including diagnosis, depression scores, suicidal ideation or acts, substance abuse, episodes/year, and %-Time ill. Results Scores for cyc ranked: BD-2Â >Â BD-1Â >Â MDD; anx ranked: MDDÂ >Â BD-2Â >Â BD-1; irr was greater in BD than MDD; dys was greater in MDD than BD; ..
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