Unipolar vs. bipolar mania: a review of 247 patients

Characterizing the clinical profile of mania without major depressive episodes: a systematic review and meta-analysis of factors associated with unipolar mania

BACKGROUND

The diagnostic concept of unipolar mania (UM), i.e. the lifetime occurrence of mania without major depressive episodes, remains a topic of debate despite the evidence accumulated in the last few years. We carried out a systematic review and meta-analysis of observational studies testing factors associated with UM as compared to bipolar disorder with a manic-depressive course (md-BD).

METHODS

Studies indexed up to July 2022 in main electronic databases were searched. Random-effects meta-analyses of the association between UM and relevant correlates yielded odds ratio (OR) or standardized mean difference (SMD), with 95% confidence intervals (CIs).

RESULTS

Based on data from 21 studies, factors positively or negatively associated with UM, as compared to md-BD, were: male gender (OR 1.47; 95% CI 1.11-1.94); age at onset (SMD -0.25; 95% CI -0.46 to -0.04); number of hospitalizations (SMD 0.53; 95% CI 0.21-0.84); family history of depression (OR 0.55; 95% CI 0.36-0.85); suicide attempts (OR 0.25; 95% CI 0.19-0.34); comorbid anxiety disorders (OR 0.35; 95% CI 0.26-0.49); psychotic features (OR 2.16; 95% CI 1.55-3.00); hyperthymic temperament (OR 1.99; 95% CI 1.17-3.40). The quality of evidence for the association with previous suicide attempts was high, moderate for anxiety disorders and psychotic features, and low or very low for other correlates.

CONCLUSIONS

Despite the heterogeneous quality of evidence, this work supports the hypothesis that UM might represent a distinctive diagnostic construct, with peculiar clinical correlates. Additional research is needed to better differentiate UM in the context of affective disorders, favouring personalized care approaches.

Characterization of clinical features and comorbidities between bipolar affective disorder with and without depressive episodes

BACKGROUNDS

A proportion of patients with bipolar disorder (BD) manifests with only unipolar mania (UM). This study examined relevant clinical features and psychosocial characteristics in UM compared with depressive-manic (D-M) subgroups. Moreover, comorbidity patterns of physical conditions and psychiatric disorders were evaluated between the UM and D-M groups.

METHODS

This clinical retrospective study (N = 1015) analyzed cases with an average of 10 years of illness duration and a nationwide population-based cohort (N = 8343) followed up for 10 years in the Taiwanese population. UM was defined as patients who did not experience depressive episodes and were not prescribed adequate antidepressant treatment during the disease course of BD. Logistic regression models adjusted for relevant covariates were used to evaluate the characteristics and lifetime comorbidities in the two groups.

RESULTS

The proportion of UM ranged from 12.91% to 14.87% in the two datasets. Compared with the D-M group, the UM group had more psychotic symptoms, fewer suicidal behaviors, a higher proportion of morningness chronotype, better sleep quality, higher extraversion, lower neuroticism, and less harm avoidance personality traits. Substantially different lifetime comorbidity patterns were observed between the two groups.

CONCLUSIONS

Patients with UM exhibited distinct clinical and psychosocial features compared with patients with the D-M subtype. In particular, a higher risk of comorbid cardiovascular diseases and anxiety disorders is apparent in patients with D-M. Further studies are warranted to investigate the underlying mechanisms for diverse presentations in subgroups of BDs.

Association of Polymorphism within the Putative miRNA Target Site in the 3'UTR Region of the DRD2 Gene with Neuroticism in Patients with Substance Use Disorder

The study aims at looking into associations between the polymorphism rs6276 that occurs in the putative miRNA target site in the 3'UTR region of the DRD2 gene in patients with substance use disorder (SUD) comorbid with a maniacal syndrome (SUD MANIA). In our study, we did not state any essential difference in DRD2 rs6276 genotype frequencies in the studied samples of SUD MANIA, SUD, and control subjects. A significant result was found for the SUD MANIA group vs. SUD vs. controls on the Neuroticism Scale of NEO FFI test, and DRD2 rs6276 (p = 0.0320) accounted for 1.7% of the variance. The G/G homozygous variants were linked with lower results on the neuroticism scale in the SUD MANIA group because G/G alleles may serve a protective role in the expression of neuroticism in patients with SUD MANIA. So far, there have been no data in the literature on the relationship between the miRSNP rs6276 region in the DRD2 gene and neuroticism (personal traits) in patients with a diagnosis of substance use disorder comorbid with the affective, maniacal type disturbances related to SUD. This is the first report on this topic.

Comparison of serum BDNF, IL-1β, IL-6, TNF-α, CRP and leucocyte levels in unipolar mania and bipolar disorder

OBJECTIVE

Unipolar mania is not included in the diagnostic and statistical manual of mental disorders-5 (DSM-5) as a separate diagnosis, although it is defined by widely accepted diagnostic criteria. The aim of this study was to investigate the differences between unipolar mania and bipolar disorder in terms of clinical and inflammatory parameters.

METHODS

The data of 495 hospitalised patients with bipolar disorder diagnoses were analysed retrospectively. Forty met the diagnostic criteria for unipolar mania. Two patients refused to participate in the study. Thirty-eight unipolar mania patients and 42 randomly selected patients with bipolar disorder diagnosis were included in the study. The two groups were compared in terms of sociodemographic, clinical characteristics, serum brain-derived neurotrophic factor, C-reactive protein (CRP), leucocyte and cytokine levels.

RESULTS

A total of 40 (8.08%) of 495 patients diagnosed with bipolar disorder met the unipolar mania diagnostic criteria. The number of manic episodes and the number of hospitalisations were statistically higher in the unipolar mania group than in the bipolar disorder group. Among all the manic symptoms, the incidence of symptoms such as euphoria, increased sexual interest, grandiosity and delusions were found to be statistically higher in the unipolar mania group. Interleukin (IL)-6 and CRP levels were significantly higher in the unipolar mania group than in the bipolar disorder group.

CONCLUSION

Unipolar mania differs from bipolar disorder in terms of clinical features and serum IL-6 and CRP levels.

Differences between unipolar mania and bipolar-I disorder: Evidence from nine epidemiological studies

OBJECTIVES

Although clinical evidence suggests important differences between unipolar mania and bipolar-I disorder (BP-I), epidemiological data are limited. Combining data from nine population-based studies, we compared subjects with mania (M) or mania with mild depression (Md) to those with BP-I with both manic and depressive episodes with respect to demographic and clinical characteristics in order to highlight differences.

METHODS

Participants were compared for gender, age, age at onset of mania, psychiatric comorbidity, temperament, and family history of mental disorders. Generalized linear mixed models with adjustment for sex and age as well as for each study source were applied. Analyses were performed for the pooled adult and adolescent samples, separately.

RESULTS

Within the included cohorts, 109 adults and 195 adolescents were diagnosed with M/Md and 323 adults and 182 adolescents with BP-I. In both adult and adolescent samples, there was a male preponderance in M/Md, whereas lifetime generalized anxiety and/panic disorders and suicide attempts were less common in M/Md than in BP-I. Furthermore, adults with mania revealed bulimia/binge eating and drug use disorders less frequently than those with BP-I.

CONCLUSIONS

The significant differences found in gender and comorbidity between mania and BP-I suggest that unipolar mania, despite its low prevalence, should be established as a separate diagnosis both for clinical and research purposes. In clinical settings, the rarer occurrence of suicide attempts, anxiety, and drug use disorders among individuals with unipolar mania may facilitate successful treatment of the disorder and lead to a more favorable course than that of BP-I disorder.

Unipolar Mania: A Particular Aspect of Bipolar Disorder in Tunisia

Objective

Unipolar mania is a clinical reality in our daily practice. Many authors suggested that bipolar patients can have only manic episodes without depressions. These findings lead us to explore more this particularity.

Methods

We conduct a retrospective, descriptive and comparative study including 173 patients, followed for bipolar disorder type I, according to the Diagnostic and Statistical Manual of Mental Disorders fifth edition criteria, during the period between January 2008 and December 2015. Two groups were identified. The first one was composed of 98 patients who had presented only manic episodes. The second group contained the rest of the sample. Unipolar mania was defined as the presence of three or more manic states without a depressive episode during the period of the study.

Results

One hundred seventy three patients were included in the study. The average age of the sample was 43 years old. The first episode was manic in 129 patients (74.6%). The dominant polarity was manic in 90.8% of the cases. Seasonal characteristic and psychotic symptoms were observed in respectively 11.0% and 53.2% of the sample. Rapid cycling evolution was observed among 2.3% of patients. The unipolar manic profile accounted for 56.6% of the population. This result is equivalent to an annual incidence of 8%. Comparing the two groups, we did not find a significant difference concerning the sociodemographic and clinical variables except for the number of suicide attempts (p=0.014).

Conclusion

Our study shows that unipolar mania is clinical evidence. More studies should be conducted in order to understand its nosological and psychopathological foundations.

Predominant mania course in Indian patients with bipolar I disorder

Many long-term follow-up studies suggest that bipolar disorder (BD) is highly recurrent and that depressive episodes are commoner than hypomania/manic episodes. However, some studies from tropical countries including India suggest that the patients experience a greater proportion of manic episodes than depressive episodes. The aim of the present study was to examine the course of BD type 1 (BD I) in a sample of hospitalized Indian subjects. We examined the clinical course of 285 BD I subjects with at least 5 years of illness using standard life charting method. These subjects were hospitalized between October 2010 and October 2012. The predominant polarity (having at least two-thirds of their lifetime episodes at one polarity) was mania (79%). Unipolar mania (≥ 3 mania episodes and no episodes of depression) was observed in 48% of the subjects. The frequency of rapid cycling course was noted in 2.5% of the subjects. Predominant manic polarity group had the illness onset mostly with a manic episode (88.9%) and the predominant depressive polarity group with a depressive episode (73.8%). Mania was the predominant polarity with a high rate of unipolar mania and a majority of the subjects had greater number of manic episodes than depressive/mixed episodes. The onset polarity determined the predominant polarity during the course of illness. Predominantly, mania course could have significant implications in the treatment of bipolar disorder.

Recurrent unipolar mania: A comparative, cross-sectional study

INTRODUCTION

A significant number of patients experience recurrent episodes of mania without depressive episodes. Evidence from the available literature suggests that these patients differ from typical "bipolar" or "manic-depressive" patients, but results have been inconsistent. The current study aims to add to this literature by comparing the demographic, clinical and risk factor profiles of patients with recurrent mania with and without depression.

METHODS

66 patients with a diagnosis of bipolar I disorder were divided into "unipolar mania" (recurrent mania alone, MA) and "bipolar" (both mania and depression, MD) sub-groups. Comorbid diagnoses were assessed using the Mini International Neuropsychiatric Interview (MINI), and genetic and environmental risk factors were explored using the Diagnostic Interview for Genetic Studies (DIGS), Childhood Trauma Questionnaire (CTQ), and an additional questionnaire designed for the purpose of the study. Differences between the MA and MD groups in terms of demographic variables, clinical profile, comorbidities and antecedent risk factors were explored.

RESULTS

Patients with both mania and depression had higher frequencies of lifetime suicide attempts, antidepressant treatment, and catatonic symptoms. There was some evidence of an association between overcrowding in childhood and the presence of depressive episodes. No other differences in demographic, clinical or risk factor variables could be found between the two groups.

DISCUSSION

Our results are consistent with the view that unipolar mania is not a distinctive disorder, or even a distinctive subtype of bipolar disorder. However, this conclusion is provisional as it is based only on clinical and demographic data.

Unipolar mania: a necessary diagnostic concept

In the classification of mood disorders, major depressive disorder is separate from bipolar disorders whereas mania is not. Studies on pure mania are therefore rare. Our paper reviews the evidence for distinguishing pure mania (M) and mania with mild depression (Md) from bipolar disorder. Two large epidemiological studies found a prevalence of 1.7-1.8% of M/Md in adolescents and adults. Several clinical follow-up studies demonstrated good stability of the diagnosis after a previous history of three manic episodes. Compared to bipolar disorder, manic disorder is characterised by a weaker family history for depression, an earlier onset, fewer recurrences and better remission, and is less comorbid with anxiety disorders. In addition, mania is strongly associated with a hyperthymic temperament, manifests more psychotic symptoms and is more often treated with antipsychotics. Twin and family studies find mania to be more heritable than depression and show no significant transmission from depression to mania or from mania to depression. Cardiovascular mortality is elevated among patients with mood disorders generally and is highest among those with mania. In non-Western countries, mania and the manic episodes in bipolar disorder are reported to occur more frequently than in Western countries.

Unipolar mania: recent updates and review of the literature

Introduction. Unipolar mania (UM) has received less than the expected attention, when compared to its contemporary mood disorders, unipolar depression (UD) and bipolar disorder (BD). Method. The literature search included PUBMED and PSYCINFO databases. Cross-searches of key references were made to identify other articles of importance. Results. There seems to be a bipolar subgroup with a stable, unipolar recurrent manic course. Although UM does not have significant differences from bipolar mania in terms of sociodemographic variables, there are certain significant differences in clinical features. UM is reported to have more grandiosity, psychotic symptoms, and premorbid hyperthymic temperament, but less rapid cycling, suicidality, seasonality, and comorbid anxiety disorders. It seems to have a better course of illness with better social and professional adjustment. However, its response to lithium prophylaxis is found to be poor as compared to classical BD and valproate could be a better choice in this case. Conclusion. The available literature suggests that UM has certain differences from classical BD. The evidence, however, is insufficient to categorize it as separate diagnostic entity. However, considering UM as a course specifier of BD would be a reasonable step.

Unipolar mania: a distinct entity?

BACKGROUND

Whether or not unipolar mania is a separate nosological entity remains a subject of dispute. This review discusses that question in light of recent data.

METHODS

Unipolar mania studies in the PUBMED database and relevant publications and cross-references were searched.

RESULTS

There seems to be a bipolar subgroup with a stable, unipolar recurrent manic course, and that 15-20% of bipolar patients may be unipolar manic. Unipolar mania may be more common in females. It seems to have a slightly earlier age of illness onset, more grandiosity, psychotic symptoms, hyperthymic temperament, but less rapid-cycling, suicidality and comorbid anxiety disorders. It seems to have a better course of illness with better social and professional adjustment. However, its response to lithium prophylaxis seems to be worse, although its response to valproate is the same when compared to that of classical bipolar.

LIMITATIONS

The few studies on the subject are mainly retrospective, and the primary methodological criticism is the uncertainty of the diagnostic criteria for unipolar mania.

CONCLUSIONS

The results indicate that unipolar mania displays some different clinical characteristics from those of classical bipolar disorder. However, whether or not it is a separate nosological entity has not been determined due to the insufficiency of relevant data. Further studies with standardized diagnostic criteria are needed. Considering unipolar mania as a course specifier of bipolar disorder could be an important step in this respect.

The identification of unipolar mania subtype based on anxiety comorbidity

BACKGROUND

Unipolar mania is a controversial topic. Clinical research has focused on establishing specific characteristics that allow it to be distinguished from bipolar disorder (BD).

METHODS

Experienced and carefully trained clinicians evaluated a clinical sample of 298 patients with bipolar disorder using structured instruments to analyze the clinical and socio-demographics differences between people with manic episodes over the course of a 15-year illness compared with participants with histories of manic and depressive episodes.

RESULTS

According to adopted criteria, 16 (5.6%) participants presented unipolar mania (UM) and 282 participants presented manic and depressive (MD) phases. UM patients reported significantly more hospitalizations and medications, as well as more frequent psychosis at the first episode in the UM group than compared to the MD group. The UM group showed worse overall functioning, although differences in mood status between groups were not identified. Comorbid anxiety disorders and anxiety symptoms occurred significantly less frequently in the UM group.

LIMITATIONS

Because of the cross-sectional design, determining causal relationships was not possible. Furthermore, the retrospective nature of the UM diagnosis could not exclude a future depressive episode.

CONCLUSIONS

The presence of anxiety disorders can differentiate patients with unipolar mania from those with bipolar mania.

Is unipolar mania a distinct subtype?

BACKGROUND

Some recent reports raised the question whether unipolar mania, without severe or mild depression, really exists and whether it defines a distinct disorder. Literature on this topic is still scarce, although this was a matter of debate since several decades.

METHOD

Eighty-seven inpatients with Diagnostic and Statistical Manual of Mental Disorder, Revised Third Edition, manic episode and at least 3 major affective episodes, in 10 years of illness duration, were systematically evaluated to collect demographic and clinical information. The symptomatological evaluation was conducted by means of the Comprehensive Psychopathological Rating Scale. Clinical features, social disability, first-degree family history, and temperaments were compared between unipolar and bipolar manics.

RESULTS

Nineteen (21.8%) of 87 patients presented a course of illness characterized by recurrent unipolar manic episodes without history of major or mild depression (MAN). When this group was compared with 68 (78.2%) manic patients with a previous history of depressive episodes (BIP), we found substantial similarities in most demographic, familial, and clinical characteristics. MAN group reported more congruent psychotic symptoms and more frequent chronic course of the current episode in comparison to BIP group. In the MAN patients, we also observed a high percentage of hyperthymic temperament and a complete absence of depressive temperament. This latter difference was statistically significant. MAN patients compared with BIP ones also reported lower severity scores in social, familial, and work disability, and they showed less depressive features, hostility, and anxiety.

CONCLUSION

The numerous demographic, clinical, and psychopathological overlapping characteristics in unipolar and bipolar mania raise questions about the general nosographic utility of this categorization. Nonetheless, our data suggest a clinical and prognostic validity of keeping unipolar manic patients as a separate subgroup, in particular, as social adjustment and disability are concerned.

The nature and treatment of depression in bipolar disorder: A review and implications for future psychological investigation

Bipolar depression is poorly understood and researched, yet it is has a huge impact on functioning in bipolar disorder. This review explores the current status of research regarding the phenomenology, natural history, neuropsychology, psychosocial predictors and cognitive style of bipolar depression. The current status of pharmacotherapy and psychological treatment of bipolar depression is also described. In particular, the manner in which cognitive behaviour therapy for bipolar depression has been adapted from CBT for unipolar depression is critically evaluated. It is concluded that there appears to be a considerable overlap between the features of unipolar and bipolar depression, yet there is also emerging evidence for specific elements. The ability of current psychological theories of bipolar disorder to account for the findings are compared, and as a consequence, a new preliminary integrative model is proposed to direct future hypothesis-led research, which will need to incorporate more suitable populations and utilise more objective methods of assessment.

Unipolar mania: a distinct disorder?

BACKGROUND

This study aimed to identify the differences between unipolar mania and classical bipolar disorder.

METHODS

Patients with at least four manic episodes and at least 4 years of follow-up without any depressive episodes were classified as unipolar mania. This group was compared to other bipolar-I patients defined according to DSM-IV regarding their clinical and socio-demographic variables.

RESULTS

The rate for unipolar mania as defined by the study criteria was found to be 16.3% in the whole group of bipolar-I patients. Unipolar manic patients tended to have more psychotic features and be less responsive to lithium prophylaxis compared to other bipolar-I patients.

LIMITATIONS

Because it was a retrospective study, there may be some minor depressive episodes left unrecorded in the unipolar mania group despite careful and thorough investigation. In addition, even with our fairly strict criteria for the diagnosis of unipolar mania, the possibility of a future depressive episode cannot be excluded.

CONCLUSIONS

Unipolar mania may be the presentation of a nosologically distinct entity.

Clinical characteristics of familial and non-familial bipolar disorder

OBJECTIVE

To explore the clinical characteristics of familial and non-familial bipolar disorder.

METHOD

Twenty subjects with bipolar disorder, who also had a family history of bipolar disorder in a first degree relative, were matched for current age, age of first onset of bipolar disorder and gender with 20 subjects with bipolar disorder who had no family history of any psychiatric disorders in first or second degree relatives.

RESULTS

Fourteen subjects in each group were female. The mean age at interview was 45.2 years and the mean age at first admission was 26 years. Although familial and non-familial probands had an equivalent number of illness episodes, familial probands were significantly more likely to experience mixed states as compared to non-familial probands. The latter experienced significantly more depressive episodes and had significantly higher neuroticism (N) scores on the Eysenck Personality Inventory (EPI; Eysenck H, Eysenck S. Manual of the Eysenck Personality Inventory. London: University of London Press, 1964.).

CONCLUSIONS

If the results are replicated, they have important implications. For example, such data may aid decisions about the targeting of additional psychosocial interventions in high N score cases. Researchers will wish to investigate whether mixed states show a stronger association with early age of onset or family history of BD.

Unipolar mania reconsidered: evidence from an elderly cohort

Earlier studies have failed to differentiate the unipolar manic subtype from bipolar patients with both manic and depressive episodes. This retrospective cohort study of 50 elderly manic in-patients identified six patients (12%) who met strict criteria for a course of unipolar mania. Significant differences emerged in age at onset, with a mean of 41.2 years for unipolar mania compared with 64.7 years for the others. Consequently, clinical course was significantly longer, 27.7 v. 7.4 years. Elderly patients pursuing a unipolar manic course are among the very few elderly 'bipolars' whose illness begins early in life. Recent neuroradiological investigations and data from geriatric studies suggest that the concept of unipolar mania is worthy of further investigation.

Socio-cultural parameters in Yoruba Nigerian patients with affective disorders

One hundred and ten consecutive new patients presenting with major affective disorders were divided into five categories according to pattern of presentation: recurrent manic disorder, recurrent depressive disorder, bipolar disorder, single episodes of manic disorder, and single episodes of major depressive disorder. Manic patients predominated, and recurrent manic disorder was much more frequent than either recurrent depressive or bipolar disorder. The manic and bipolar patients were younger. Females predominated in all five groups of patients. The two manic groups were less likely to be married, but this was probably a reflection of their younger age. No differences were demonstrated with regard to educational status or occupation. There were no significant differences with regard to sibship position, family size, or polygamous/monogamous parents. Manic patients were more likely to have suffered permanent separation from one or both parents before the age of 12 years. A relatively low proportion of the patients had a positive history of mental disorder among first- or second-degree relatives. Manic and bipolar patients tended to present in hospital relatively early in their illness.

Bipolar affective disorder: causes and prevention of relapse

The majority of patients with bipolar affective disorder relapse at least once during their lifetime, most several times, often with disastrous consequences. In this review we examine those factors which appear to play a facilitatory and in some cases, a causal role in determining whether a relapse will occur and, if so, when. Such factors include: the season of the year, with most admissions for mania in the British Isles occurring in the summer months; change in endocrine status, as after childbirth or when there is impaired thyroid function; treatment with drugs affecting central monoamine, particularly dopamine, neurotransmission; untoward life events. We evaluate the relative efficacy of treatments for the prevention of relapse, such as lithium, carbamazepine and antipsychotics, in the context of social and psychological support systems.

Clinical and socio-cultural parameters in Nigerian psychiatric patients. A prospective study

Three hundred and eighteen consecutive new patients presenting at a psychiatric unit in Yorubaland were prospectively studied. The majority were young, and the sexes were equally represented. Most patients came from within 50 km of the unit. Most were brought by their blood-relatives. Significant delay before presentation was observed in most cases. Previous treatment by religious and/or traditional healers was common. According to the DSM-III classification, the majority suffered from functional psychoses, most commonly schizophrenia. Three quarters received neuroleptic medication. The immediate clinical outcome was good in the majority of cases; however, within 6 months of presentation almost half defaulted from treatment. Variables which appeared to be related to delay in presentation, prior treatment by religious or traditional healers and defaulting are presented.

Recurrent unipolar manic disorder in the Yoruba Nigerian: further evidence

One hundred and four Yoruba Nigerian patients are described who presented with manic disorder over a five-year period; 55 could be classified as suffering from recurrent unipolar manic disorder, while 36 had suffered only one attack of mania. Only 13 patients suffered from bipolar disorder, in contrast to studies from Western societies, in which bipolar disorder is much more common than unipolar. The unipolar manic and bipolar patients could not be differentiated on the basis of clinical and social data, apart from a possible preponderance of the female sex in the bipolar group. The clinical presentation of mania was similar to that described from Western Countries. Long-term prophylaxis with depot neuroleptics may be advisable in such cases.