Lithium blocks 45Ca2+ uptake into platelets in bipolar affective disorder and controls.

The basal uptake of radiolabelled 45Ca2+ into platelets and the effect of 1 mM lithium on uptake was measured in manic (n = 13) and depressed (n = 15) patients with bipolar disorder and in controls (n = 13). Lithium was significantly associated with inhibition of uptake of 45Ca2+ into platelets in all three groups. There were no significant intergroup differences in either basal levels of calcium uptake or the effects of lithium on calcium uptake (analysis of variance).

The impact of age at onset of bipolar I disorder on functioning and clinical presentation

Objectives: Recent studies have proposed the existence of three distinct subgroups of bipolar 1 disorder based on age at onset (AAO). The present study aims to investigate potential clinical and functional differences between these subgroups in an Australian sample.

Methods: Participants (n = 239) were enrolled in the Bipolar Comprehensive Outcomes Study (BCOS), a 2-year longitudinal, observational, cross-sectional study. Assessment measures included the Young Mania Rating Scale (YMRS), Hamilton Depression Rating Scale (HAMD21), Clinical Global Impressions Scale (CGI-BP), SF-36, SLICE/Life Scale, and the EuroQol (EQ-5D). Participants were also asked about their age at the first major affective episode.

Results: Three AAO groups were compared: early (AAO < 20, mean = 15.5 ± 2.72; 44.4% of the participants); intermediate (AAO 20–39, mean = 26.1 ± 4.8; 48.14% of the participants) and late (AAO > 40, mean = 50.6 ± 9.04; 7.4% of the participants). Higher rates of depression, suicidal ideation and binge drinking were reported by the early AAO group. This group also reported poorer quality of life in a number of areas. The early AAO group had a predominant depressive initial polarity and the intermediate group had a manic predominance.

Conclusion: Early AAO is associated with an adverse outcome.

Bipolar II disorder : a review

Objectives: To review the current knowledge of bipolar II disorder.

Methods: Literature was reviewed after conducting a Medline search and a hand search of relevant literature.

Results: Bipolar II disorder is a common disorder, with a prevalence of approximately 3–5%. Distinct clinical features of bipolar II disorder have been described. The key to diagnosis is the recognition of past hypomania, while depression is the typical presenting feature of the illness. This is responsible for a significant rate of missed diagnosis, and consequent management according to unipolar guidelines. It is unclear if bipolar II disorder is over-represented amongst resistant depression populations and if abrupt offset of antidepressant action is a phenomenon over represented in bipolar II disorder, reflecting induction of predominantly depressive cycling. A few mood-stabilizer studies available provide provisional suggestion of utility. A supportive role for psychosocial therapies is suggested, however, there is a sparsity of published studies specific to bipolar II disorder cohorts. A small number of short-term antidepressant trials have suggested efficacy, however, compelling long-term maintenance data is absent.

Conclusions: An emerging literature on the specific clinical signature and management of the disorder exists, however, this is disproportionately small relative to the epidemiology and clinical significance of the disorder.

A prospective study of the impact of subthreshold mixed states on the 24-month clinical outcomes of bipolar I disorder or schizoaffective disorder

Objectives: Subthreshold mixed states are common, yet their clinical significance is unclear. This study investigated the clinical outcomes of subthreshold mixed states in participants with bipolarI disorder or schizoaffective disorder, using the Cassidy and Benazzi criteria for manic and depressive mixed states, respectively.

Methods: The Bipolar Comprehensive Outcomes Study (BCOS) is a prospective observational study of treatment and outcomes for patients with bipolar I or schizoaffective disorder, bipolar type. Participants (N=239) were grouped based on study entry clinical presentation as having pure depression (n=63) if they satisfied DSM-IV-TR criteria for a Major Depressive Episode (MDE), depressive mixed state (DMX) if they also had at least three concurrent hypomanic symptoms (n=33), or not depressed (n=143) if they did not satisfy the criteria for MDE. Participants were similarly grouped as having pure mania (n=3) if they satisfied DSM-IV criteria for a Manic Episode, manic mixed state (MMX) if they also had at least two concurrent depressive symptoms (n=33), or not manic (n=203). Clinical data were collected by interview every 3-months over a 24-month period.

Results: Measures of quality of life, mental and physical health over the 24-month period were significantly worse for participants who were classified as having mixed states at study entry on most outcome measures compared to participants who were not in an illness episode at study entry. DMX was predictive of greater manic symptomatology over the 24 months compared to participants with pure depression.

Conclusion: In participants with a current episode of mood disorder, the presence of subthreshold symptoms of opposite polarity was associated with poorer clinical outcomes over a 24-month period.

Meta-analytic review of neurocognition in bipolar II disorder

Objective: The clinical distinction between bipolar II disorder (BD II) and bipolar I disorder (BD I) is not clear-cut. Cognitive functioning offers the potential to explore objective markers to help delineate this boundary. To examine this issue, we conducted a quantitative review of the cognitive profile of clinically stable patients with BD II in comparison with both patients with BD I and healthy controls.
Method: Meta-analytical methods were used to compare cognitive functioning of BD II disorder with both BD I disorder and healthy controls.
Results: Individuals with BD II were less impaired than those with BD I on verbal memory. There were also small but significant difference in
visual memory and semantic fluency. There were no significant differences in global cognition or in other cognitive domains. Patients with BD II performed poorer than controls in all cognitive domains.
Conclusion: Our findings suggest that with the exception of memory and semantic fluency, cognitive impairment in BD II is as severe as in BD I. Further studies are needed to investigate whether more severe deficits in BD I are related to neurotoxic effects of severe manic episodes on medial temporal structures or neurobiological differences from the onset of the illness.

Influence of birth cohort on age of onset cluster analysis in bipolar I disorder

Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.