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Relatively few studies have investigated whether relatives of patients with bipolar disorder show brain functional changes, and these have focused on activation changes. Failure of de-activation during cognitive task performance is also seen in the disorder and may have trait-like characteristics since it has been found in euthymia.
A total of 20 euthymic patients with bipolar disorder, 20 of their unaffected siblings and 40 healthy controls underwent functional magnetic resonance imaging during performance of the n-back working memory task. An analysis of variance (ANOVA) was fitted to individual whole-brain maps from each set of patient–relative–matched pair of controls. Clusters of significant difference among the groups were used as regions of interest to compare mean activations/de-activations between them.
A single cluster of significant difference among the three groups was found in the whole-brain ANOVA. This was located in the medial prefrontal cortex, a region of task-related de-activation in the healthy controls. Both the patients and their siblings showed significantly reduced de-activation compared with the healthy controls in this region, but the failure was less marked in the relatives.
Failure to de-activate the medial prefrontal cortex in both euthymic bipolar patients and their unaffected siblings adds to evidence for default mode network dysfunction in the disorder, and suggests that it may act as a trait marker.
Little is known about how functional imaging changes in bipolar disorder
relate to different phases of the illness.
To compare cognitive task activation in participants with bipolar
disorder examined in different phases of illness.
Participants with bipolar disorder in mania (n = 38),
depression (n = 38) and euthymia (n =
38), as well as healthy controls (n = 38), underwent
functional magnetic resonance imaging during performance of the n-back
working memory task. Activations and de-activations were compared between
the bipolar subgroups and the controls, and among the bipolar subgroups.
All participants were also entered into a linear mixed-effects model.
Compared with the controls, the mania and depression subgroups, but not
the euthymia subgroup, showed reduced activation in the dorsolateral
prefrontal cortex, the parietal cortex and other areas. Compared with the
euthymia subgroup, the mania and depression subgroups showed
hypoactivation in the parietal cortex. All three bipolar subgroups showed
failure of de-activation in the ventromedial frontal cortex. Linear
mixed-effects modelling revealed a further cluster of reduced activation
in the left dorsolateral prefrontal cortex in the patients; this was
significantly more marked in the mania than in the euthymia subgroup.
Bipolar disorder is characterised by mood state-dependent hypoactivation
in the parietal cortex. Reduced dorsolateral prefrontal activation is a
further feature of mania and depression, which may improve partially in
euthymia. Failure of de-activation in the medial frontal cortex shows
Schizo-affective disorder has not been studied to any significant extent using functional imaging. The aim of this study was to examine patterns of brain activation and deactivation in patients meeting strict diagnostic criteria for the disorder.
Thirty-two patients meeting Research Diagnostic Criteria (RDC) for schizo-affective disorder (16 schizomanic and 16 schizodepressive) and 32 matched healthy controls underwent functional magnetic resonance imaging (fMRI) during performance of the n-back task. Linear models were used to obtain maps of activations and deactivations in the groups.
Controls showed activation in a network of frontal and other areas and also deactivation in the medial frontal cortex, the precuneus and the parietal cortex. Schizo-affective patients activated significantly less in prefrontal, parietal and temporal regions than the controls, and also showed failure of deactivation in the medial frontal cortex. When task performance was controlled for, the reduced activation in the dorsolateral prefrontal cortex (DLPFC) and the failure of deactivation of the medial frontal cortex remained significant.
Schizo-affective disorder shows a similar pattern of reduced frontal activation to schizophrenia. The disorder is also characterized by failure of deactivation suggestive of default mode network dysfunction.
The long-term efficacy of psychological interventions for bipolar
disorders has not been tested.
This study assessed the efficacy of group psychoeducation to prevent
recurrences and to reduce time spent ill for people with bipolar
A randomised controlled trial with masked outcome assessment comparing
group psychoeducation and non-structured group intervention during 5-year
follow-up. One hundred and twenty people with bipolar disorders were
included in the study and 99 completed 5-year follow-up. Time to any
recurrence, number of recurrences, total number of days spent ill,
frequency and length of hospitalisations were the main outcome
At the 5-year follow-up, time to any recurrence was longer for the
psychoeducation group (log rank=9.953, P<0.002). The
psychoeducation group had fewer recurrences (3.86 v.
8.37, F=23.6, P<0.0001) of any type
and they spent less time acutely ill (154 v. 586 days,
F=31.66, P=0.0001). The median
number of days of hospitalisation per hospitalised participant was also
lower for the psychoeducation group (45 v. 30,
Six-month group psychoeducation has long-lasting prophylactic effects in
individuals with bipolar disorders. Group psychoeducation is the first
psychological intervention showing such a long-term maintained efficacy
in people with bipolar disorders.
More than 20% of bipolar patients may present with seasonal pattern (SP). Seasonality can alter the course of bipolar disorder. However, to date, long-term follow-up studies of bipolar patients presenting with SP are scarce. We present a 10-year follow-up study comparing clinical and demographic features of bipolar patients with and without SP.
Three hundred and twenty-five bipolar I and II patients were followed up for at least 10 years. SP was defined according to DSM-IV criteria. Clinical variables were obtained from structured interviews with the patients and their relatives. Patients with and without SP were compared regarding clinical and sociodemographic variables and a stepwise logistic regression was performed.
Seventy-seven patients (25·5%) were classified as presenting with SP, while 225 (74·5%) were considered as presenting with no significant seasonal variation. Twenty-three patients (7%) were excluded from the study because it was unclear whether they had seasonality or not. There were no differences between groups regarding demographic variables. Patients with SP predominantly presented with bipolar II disorder, depressive onset, and depressive predominant polarity. The greater burden of depression did not correlate with indirect indicators of severity, such as suicidality, hospitalizations or psychotic symptoms.
Our study links the presence of SP with both bipolar II disorder and predominant depressive component. However, we could not find any difference regarding functionality or hospitalization rates. Modifications in the criteria to define SP are suggested for a better understanding of bipolar disorder.
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