Long-term outcome of lithium prophylaxis in bipolar disorder with mood-incongruent psychotic features: a prospective study

Sex differences in bipolar disorder: The dorsolateral prefrontal cortex as an etiopathogenic region

Bipolar disorder (BD) is worldwide a prevalent mental illness and a leading risk factor for suicide. Over the past three decades, it has been discovered that sex differences exist throughout the entire panorama of BD, but the etiologic regions and mechanisms that generate such differences remain poorly characterized. Available evidence indicates that the dorsolateral prefrontal cortex (DLPFC), a critical region that controls higher-order cognitive processing and mood, exhibits biological disparities between male and female patients with psychiatric disorders, which are highly correlated with the co-occurrence of psychotic symptoms. This review addresses the sex differences in BD concerning epidemiology, cognitive impairments, clinical manifestations, neuroimaging, and laboratory abnormalities. It also provides strong evidence linking DLPFC to the etiopathogenesis of these sex differences. We emphasize the importance of identifying gene signatures using human brain transcriptomics, which can depict sexually different variations, explain sex-biased symptomatic features, and provide novel targets for sex-specific therapeutics.

Clinicodemographic correlates of psychotic features in bipolar disorder - a multicenter study in China

BACKGROUND

Psychotic symptoms are prevalent in patients with bipolar disorder (BD). However, nearly all previous studies on differences in sociodemographic and clinical factors between patients with (BD P +) and without (BD P-) psychotic symptoms were conducted in Western populations, and limited information is known in China.

METHOD

A total of 555 patients with BD from seven centers across China were recruited. A standardized procedure was used to collect patients' sociodemographic and clinical characteristics. The patients were divided into BD P + or BD P- groups based on the presence of lifetime psychotic symptoms. Mann-Whitney U test or chi-square test was used to analyze differences in sociodemographic and clinical factors between patients with BD P + and BD P-. Multiple logistic regression analysis was conducted to explore factors that were independently correlated with psychotic symptoms in BD. All the above analyses were re-conducted after the patients were divided into BD I and BD II group according to their types of diagnosis.

RESULTS

A total of 35 patients refused to participate, and the remaining 520 patients were included in the analyses. Compared with patients with BD P-, those with BD P + were more likely to be diagnosed with BD I and mania/hypomania/mixed polarity in the first mood episode. Moreover, they were more likely to be misdiagnosed as schizophrenia than major depressive disorder, were hospitalized more often, used antidepressants less frequently, and used more antipsychotics and mood stabilizers. Multivariate analyses revealed that diagnosis of BD I, more frequent misdiagnosis as schizophrenia and other mental disorders, less frequent misdiagnosis as major depressive disorder, more frequent lifetime suicidal behavior, more frequent hospitalizations, less frequent use of antidepressants, more frequent use of antipsychotics and mood stabilizers were independently correlated with psychotic symptoms in BD. After dividing the patients into BD I and BD II groups, we observed notable differences in sociodemographic and clinical factors, as well as clinicodemographic correlates of psychotic features between the two groups.

CONCLUSIONS

Differences in clinical factors between patients with BD P + and BD P- showed cross-cultural consistency, but results on the clinicodemographic correlates of psychotic features were not. Notable differences between patients with BD I and BD II were found. Future work exploring the psychotic features of BD needs to take types of diagnosis and cultural differences into consideration.

TRIAL REGISTRATION

This study was first registered on the website of the ClinicalTrials.gov ( https://clinicaltrials.gov/ ) on 18/01/2013. Its registration number is NCT01770704.

Psychotic features, particularly mood incongruence, as a hallmark of severity of bipolar I disorder

BACKGROUND

The occurrence of psychotic features within mood episodes in patients with bipolar I disorder (BD I) has been associated in some studies with a more severe clinical and socio-professional profile. In contrast, other studies establishing the associations of psychotic features in BD I, and in particular of mood-congruent (MC) and mood-incongruent (MI) features, with clinical characteristics have yielded contradictory results. However, many pre-existing studies have been affected by serious methodological limitations. Using a sample of thoroughly assessed patients with BD I our aims were to: (1) establish the proportion of those with MI and MC features, and (2) compare BD I patients with and without psychotic features as well as those with MI to those with MC features on a wide array of socio-demographic and clinical characteristics including course, psychiatric comorbidity and treatment.

METHODS

A sample of 162 treated patients with BD I (60.5% female, mean age = 41.4 (s.d: 10.2) years) was recruited within a large family study of mood disorders. Clinical, course and treatment characteristics relied on information elicited through direct diagnostic interviews, family history reports and medical records.

RESULTS

(1) A total of 96 patients (59.3%) had experienced psychotic features over their lifetime. Among them, 44.8% revealed MI features at least once in their lives. (2) Patients with psychotic features were much less likely to be professionally active, revealed alcohol abuse more frequently and used health care, particularly inpatient treatment, more frequently than those without psychotic features. Within patients with psychotic symptoms, those with MI features showed more clinical severity in terms of a higher likelihood of reporting hallucinations, suicidal attempts and comorbid cannabis dependence.

CONCLUSION

Our data provide additional support for both the distinction between BD-I with and without psychotic features as well as the distinction between MI and MC psychotic features. The more severe course of patients with psychotic features, and particularly those with MI psychotic features, highlights the need for thorough psychopathological evaluations to assess the presence of these symptoms to install appropriate treatment.

Psychotic symptoms in bipolar disorder and their impact on the illness: A systematic review

BACKGROUND

Lifetime psychotic symptoms are present in over half of the patients with bipolar disorder (BD) and can have an adverse effect on its course, outcome, and treatment. However, despite a considerable amount of research, the impact of psychotic symptoms on BD remains unclear, and there are very few systematic reviews on the subject.

AIM

To examine the extent of psychotic symptoms in BD and their impact on several aspects of the illness.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. An electronic literature search of six English-language databases and a manual search was undertaken to identify published articles on psychotic symptoms in BD from January 1940 to December 2021. Combinations of the relevant Medical Subject Headings terms were used to search for these studies. Articles were selected after a screening phase, followed by a review of the full texts of the articles. Assessment of the methodological quality of the studies and the risk of bias was conducted using standard tools.

RESULTS

This systematic review included 339 studies of patients with BD. Lifetime psychosis was found in more than a half to two-thirds of the patients, while current psychosis was found in a little less than half of them. Delusions were more common than hallucinations in all phases of BD. About a third of the patients reported first-rank symptoms or mood-incongruent psychotic symptoms, particularly during manic episodes. Psychotic symptoms were more frequent in bipolar type I compared to bipolar type II disorder and in mania or mixed episodes compared to bipolar depression. Although psychotic symptoms were not more severe in BD, the severity of the illness in psychotic BD was consistently greater. Psychosis was usually associated with poor insight and a higher frequency of agitation, anxiety, and hostility but not with psychiatric comorbidity. Psychosis was consistently linked with increased rates and the duration of hospitalizations, switching among patients with depression, and poorer outcomes with mood-incongruent symptoms. In contrast, psychosis was less likely to be accompanied by a rapid-cycling course, longer illness duration, and heightened suicidal risk. There was no significant impact of psychosis on the other parameters of course and outcome.

CONCLUSION

Though psychotic symptoms are very common in BD, they are not always associated with an adverse impact on BD and its course and outcome.

A two-year follow-up study on the first manic episode due to mood-incongruent psychosis

BACKGROUND

Mood-incongruent psychosis during bipolar disorder has been associated with poor outcomes. However, it remains unknown whether this is secondary to persistent affective or psychotic symptoms or both.

METHOD

Sixty-eight patients with bipolar disorder between the ages of 16 and 45 were recruited during their first psychiatric hospitalization for mania. These patients were evaluated using structured and semi-structured clinical interview then followed longitudinally. Outcomes during the first twenty-four months of follow-up were compared between patients with mood-incongruent psychosis and those without (i.e., patients with mood-congruent psychosis or no psychosis) during the index manic episode. Specifically, ratings of the percent of weeks during follow-up with the duration of mood incongruent psychotic symptom, any psychotic symptom, affective syndromes, and scores of global outcomes were compared.

RESULTS

Comparing the 24-month follow-up results between the two groups, patients with mood incongruent psychotic symptoms had a lower global functional rating scale, efficacy index, while the duration of mood incongruent psychotic symptom, any psychotic symptom, and complete affective symptom showed statistically significant differences between the two groups. There were also statistically significant differences between the two groups in the duration of mood stabilizers, and antidepressants use, typical antipsychotics, and atypical antipsychotics. Partial correlation analysis reveals the scores of the global assessment of functioning scale (GAF) after 24 months showed a significant negative correlation with the length of time of incongruent psychotic symptoms. Still, the correlation was intermediate (correlation coefficients less than 0.5，r² = -0.471, P < 0.001).

CONCLUSION

Mood-incongruent psychosis that occurs during the first manic episode appears to predict an increased likelihood of persistent psychotic symptoms during the subsequent twenty-four months. This persistence of psychosis is associated with a worse overall course of illness than patients without mood-incongruent psychosis.

LIMITATIONS

These results apply to a relatively short outcome period, and the sample size is relatively small.

Guidelines for the management of psychosis in the context of mood disorders

Psychotic episodes occur in a substantial proportion of patients suffering from major mood disorders (both unipolar and bipolar) at some point in their lives. The nature of these episodes is less well understood than the more common, non-psychotic periods of illness and hence their management is also less sophisticated. This is a concern because the risk of suicide is particularly high in this subtype of mood disorder and comorbidity is far more common. In some cases psychotic symptoms may be signs of a comorbid illness but the relationship of psychotic mood to other forms of psychosis and in particular its interactions with schizophrenia is poorly understood. Therefore, our targeted review draws upon extant research and our combined experience to provide clinical context and a framework for the management of these disorders in real-world practice - taking into consideration both biological and psychological interventions.

The characteristics of psychotic features in bipolar disorder

BACKGROUND

In a large and comprehensively assessed sample of patients with bipolar disorder type I (BDI), we investigated the prevalence of psychotic features and their relationship with life course, demographic, clinical, and cognitive characteristics. We hypothesized that groups of psychotic symptoms (Schneiderian, mood incongruent, thought disorder, delusions, and hallucinations) have distinct relations to risk factors.

METHODS

In a cross-sectional study of 1342 BDI patients, comprehensive demographical and clinical characteristics were assessed using the Structured Clinical Interview for DSM-IV (SCID-I) interview. In addition, levels of childhood maltreatment and intelligence quotient (IQ) were assessed. The relationships between these characteristics and psychotic symptoms were analyzed using multiple general linear models.

RESULTS

A lifetime history of psychotic symptoms was present in 73.8% of BDI patients and included delusions in 68.9% of patients and hallucinations in 42.6%. Patients with psychotic symptoms showed a significant younger age of disease onset (β = -0.09, t = -3.38, p = 0.001) and a higher number of hospitalizations for manic episodes (F11 338 = 56.53, p < 0.001). Total IQ was comparable between groups. Patients with hallucinations had significant higher levels of childhood maltreatment (β = 0.09, t = 3.04, p = 0.002).

CONCLUSIONS

In this large cohort of BDI patients, the vast majority of patients had experienced psychotic symptoms. Psychotic symptoms in BDI were associated with an earlier disease onset and more frequent hospitalizations particularly for manic episodes. The study emphasizes the strength of the relation between childhood maltreatment and hallucinations but did not identify distinct subgroups based on psychotic features and instead reported of a large heterogeneity of psychotic symptoms in BD.

Genome-wide association of mood-incongruent psychotic bipolar disorder

Mood-incongruent psychotic features (MICP) are familial symptoms of bipolar disorder (BP) that also occur in schizophrenia (SZ), and may represent manifestations of shared etiology between the major psychoses. In this study we have analyzed three large samples of BP with imputed genome-wide association data and have performed a meta-analysis of 2196 cases with MICP and 8148 controls. We found several regions with suggestive evidence of association (P<10(-6)), although no marker met genome-wide significance criteria. The top associations were on chromosomes: 6q14.2 within the PRSS35/SNAP91 gene complex (rs1171113, P=9.67 × 10(-8)); 3p22.2 downstream of TRANK/LBA1 (rs9834970, P=9.71 × 10(-8)); and 14q24.2 in an intron of NUMB (rs2333194, P=7.03 × 10(-7)). These associations were present in all three samples, and both rs1171113 and rs2333194 were found to be overrepresented in an analysis of MICP cases compared with all other BP cases. To test the relationship of MICP with SZ, we performed polygenic analysis using the Psychiatric GWAS Consortium SZ results and found evidence of association between SZ polygenes and the presence of MICP in BP cases (meta-analysis P=0.003). In summary, our analysis of the MICP phenotype in BP has provided suggestive evidence for association of common variants in several genes expressed in the nervous system. The results of our polygenic analysis provides support for a modest degree of genetic overlap between BP with MICP and SZ, highlighting that phenotypic correlations across syndromes may be due to the influence of polygenic risk factors.

Microtubule-associated protein tau in development, degeneration and protection of neurons

As a principal neuronal microtubule-associated protein, tau has been recognized to play major roles in promoting microtubule assembly and stabilizing the microtubules and to maintain the normal morphology of the neurons. Recent studies suggest that tau, upon alternative mRNA splicing and multiple posttranslational modifications, may participate in the regulations of intracellular signal transduction, development and viability of the neurons. Furthermore, tau gene mutations, aberrant mRNA splicing and abnormal posttranslational modifications, such as hyperphosphorylation, have also been found in a number of neurodegenerative disorders, collectively known as tauopathies. Therefore, changes in expression of the tau gene, alternative splicing of its mRNA and its posttranslational modification can modulate the normal architecture and functions of neurons as well as in a situation of tauopathies, such as Alzheimer's disease. The primary aim of this review is to summarize the latest developments and perspectives in our understanding about the roles of tau, especially hyperphosphorylation, in the development, degeneration and protection of neurons.

The behavioral actions of lithium in rodent models: leads to develop novel therapeutics

For nearly as long as lithium has been in clinical use for the treatment of bipolar disorder, depression, and other conditions, investigators have attempted to characterize its effects on behaviors in rodents. Lithium consistently decreases exploratory activity, rearing, aggression, and amphetamine-induced hyperlocomotion; and it increases the sensitivity to pilocarpine-induced seizures, decreases immobility time in the forced swim test, and attenuates reserpine-induced hypolocomotion. Lithium also predictably induces conditioned taste aversion and alterations in circadian rhythms. The modulation of stereotypy, sensitization, and reward behavior are less consistent actions of the drug. These behavioral models may be relevant to human symptoms and to clinical endophenotypes. It is likely that the actions of lithium in a subset of these animal models are related to the therapeutic efficacy, as well the side effects, of the drug. We conclude with a brief discussion of various molecular mechanisms by which these lithium-sensitive behaviors may be mediated, and comment on the ways in which rat and mouse models can be used more effectively in the future to address persistent questions about the therapeutically relevant molecular actions of lithium.

Olanzapine versus placebo in acute mania: treatment responses in subgroups

Two double-blind, placebo-controlled trials of olanzapine in acute mania showed significant overall antimanic efficacy, based on reductions in mania ratings. Their subject-level data were pooled to increase statistical power to test for differences in treatment responses among 10 subgroup pairs of interest using generalized estimating equations methods. Similar drug/placebo superiority and responsiveness to olanzapine was found in men versus women, psychotic versus nonpsychotic subjects, and those presenting in mania versus mixed states, and responses were independent of onset age, current age, or prior illness based on episodes, hospitalizations, recent rapid cycling, lifetime substance use, or previous antipsychotic treatment. Olanzapine and placebo responses paralleled closely (r(s) = 0.73). Patients were relatively more responsive to olanzapine who were younger at illness onset, lacked prior substance abuse, and had not previously received antipsychotic treatment (efficacy ratios 1.5-1.7, all P < 0.01). These well-powered comparisons of subgroups of interest indicate broad efficacy of olanzapine in the treatment of acute mania.

The effect of lithium in bipolar disorder: a review of recent research evidence

Recently published clinical research on lithium is briefly reviewed. The antimanic effect of lithium is supported by recent evidence. It is confirmed that a drastic reduction of affective morbidity is very frequent in bipolar patients receiving lithium prophylaxis regularly for several years, but that the impact of prophylaxis on the course of bipolar disorder is significantly limited by the high drop-out rate. Lithium does seem to be efficacious also in bipolar disorder with mood-incongruent psychotic features or with rapid cycling. The effect of lithium prophylaxis does not seem to decrease over time, at least in the large majority of patients. The recurrence risk is increased in the months following lithium discontinuation. Lithium seems to exert an antisuicidal effect in bipolar patients.