White matter hyperintensities in bipolar and unipolar mood disorder subjects with relatively mild-to-moderate illness severity

BACKGROUND: Increased rates of white matter hyperintense lesions have been reported in mood disorder patients. However, the potential effects of age and illness severity on reported findings are not fully established. We examined the rates of hyperintense lesions in adult, non-elderly bipolar and unipolar patients, with a relatively mild-to-moderate illness severity, and in matched healthy controls. METHOD: We examined brain MRI images in 24 bipolar (19-56 years, mean+/-S.D.=34.2+/-9.9 years) and 17 unipolar patients (24-59 years, 42.8+/-9.2 years), and 38 healthy controls (21-59 years, 36.8+/-9.7 years). T2-weighted and proton-density axial MRI images were obtained at 1.5 Tesla. The lesions were rated by two independent raters, using a semi-quantitative rating scale. RESULTS: There were no significant differences in the frequency of hyperintensities between bipolar or unipolar patients and healthy controls. Age was related to the presence of subcortical gray matter hyperintensities for the whole sample. Among the unipolar patients, length of illness and presence of mood disorder in a first-degree relative were related to deep and periventricular white matter lesions, respectively. LIMITATIONS: The methodology utilized for measurement of the white matter hyperintensities was semi-quantitative. CONCLUSIONS: Increased rates of white matter hyperintensities do not appear to be present in a group of relatively young mood disorder patients, with relatively mild to moderate illness severity. These brain lesions may be more directly related to late-life and more severe cases of these illnesses

Corpus callosum signal intensity in bipolar and unipolar disorder patients

BACKGROUND: Anatomical abnormalities in the corpus callosum have been reported in magnetic resonance imaging (MRI) studies in patients with bipolar but not unipolar disorder. MRI signal intensity can be used as a putative index of corpus callosum myelination. OBJECTIVES: To measure MRI signal intensity in patients with bipolar and unipolar disorder to investigate abnormalities of corpus callosum myelination. METHODS: The study involved 29 DSM-IV bipolar patients (mean (SD) age, 35 (11) years; 16 male, 13 female), 23 DSM-IV unipolar patients (41 (10) years; 4 male, 19 female), and 36 healthy controls (37 (10) years; 23 male, 13 female). A 1.5T GE Signa magnet was employed, with a fast spin echo sequence. Corpus callosum signal intensity was obtained blindly using the semiautomated software NIH Image 1.62. RESULTS: Bipolar patients had lower corpus callosum signal intensity for all callosal subregions (genu, anterior and posterior body, isthmus, splenium) than healthy controls (ANCOVA, age and sex as covariates, p0.05). CONCLUSIONS: The findings suggest abnormalities in corpus callosum white matter in bipolar but not unipolar patients, possibly because of altered myelination. Such abnormalities could lead to impaired interhemispheric communication in bipolar disorder. Longitudinal MRI studies involving first episode and early onset bipolar patients will be necessary for a better understanding of the potential role of abnormalities of corpus callosum myelination in the pathophysiology of bipolar disorder

MRI study of posterior fossa structures and brain ventricles in bipolar disorder patients

Previous brain imaging studies have suggested anatomical abnormalities in posterior fossa structures and brain ventricles in bipolar patients. Such abnormalities could possibly be implicated in the pathophysiology of bipolar disorder. Twenty-two DSM-IV bipolar outpatients (mean age+/-S.D.=36+/-10 years) and 22 healthy controls (mean age+/-S.D.=38+/-10 years) underwent an 1.5T MRI (3D-gradient echo-imaging SPGR), performed in the coronal plane (TR=25 ms, TE=5 ms, slice thickness=1.5 mm). The brain structures of interest were traced blindly with a semi-automated software. No significant differences were found between bipolar patients and healthy controls for any posterior fossa measures, or for measures of third or lateral ventricles (MANOVA, age covariate, P>0.05). Age was directly correlated with 3rd ventricle volumes in bipolar patients (Pearson correlation coefficient=0.458, P=0.032), but not in healthy controls (Pearson correlation coefficient=0.313, P=0.155). There was a significant direct correlation between the number of prior illness episodes and right lateral ventricle volumes (Partial correlation coefficient=0.658, P=0.011). Familial patients had smaller left and right cerebellar hemispheres and total vermis volumes, and larger left lateral ventricle volumes compared with non-familial ones (MANOVA, age covariate, P<0.05). In this preliminary study, we were not able to replicate previous findings of abnormalities in cerebellum or brain ventricles in bipolar individuals. However, there were suggestions that abnormalities in cerebellum, vermis, and lateral ventricle sizes may be present in familial cases of the disorder, which should be further examined in future studies with larger patient samples

Differential effects of age on brain gray matter in bipolar patients and healthy controls

This study examined possible differences in total gray and white matter brain content in bipolar patients and healthy individuals, and their relationship with age. 22 DSM-IV bipolar patients and 22 healthy controls underwent a 1.5-tesla Spoiled Gradient Recalled Acquisition (SPGR) MRI. Evaluators blind to patients' identities measured total brain, gray and white matter volumes using a semi-automated software. No differences were found for total brain volume, gray matter or white matter volumes between bipolar patients and healthy controls (MANCOVA, age as covariate, p > 0.05). Age was inversely correlated with total gray matter volume in patients (r = -0.576, p = 0.005), but not in controls (r = -0.193, p = 0.388). Our findings suggest that any existing gray matter deficits in bipolar disorder are likely to be localized to specific brain regions, rather than generalized. The inverse correlation between age and brain gray matter volumes in bipolar patients, not present in healthy controls, in this sample of mostly middle-aged adults, could possibly indicate more pronounced age-related gray matter decline in bipolar patients, and may be of potential relevance for the pathophysiology of the disorder

MRI study of corpus callosum abnormalities in bipolar patients

BACKGROUND: This study was conducted to further examine the hypothesis of abnormalities in size of corpus callosum in subjects with bipolar disorder. METHODS: Sixteen right-handed DSM-IV bipolar I patients and 27 right-handed healthy control subjects were studied. A 1.5-T GE Signa magnet was used, and three-dimensional gradient echo imaging (spoiled gradient recall acquisition) was conducted. Area measurements of corpus callosum were obtained blindly, with a semi-automated software, by a well-trained rater. RESULTS: Right-handed bipolar I patients had significantly smaller total corpus callosum, genu, posterior body, and isthmus areas compared with right-handed healthy control subjects (analysis of covariance with age, gender, and intracranial volume as covariates, p .05). CONCLUSIONS: Smaller callosal areas may lead to altered inter-hemispheric communication and be involved in the pathophysiology and cognitive impairment found in bipolar disorder

1H MRS Brain Measures and acute lorazepam administration in healthy human subjects

The effects of acute lorazepam administration on 1H magnetic resonance spectroscopy (MRS) in vivo brain spectra were examined in the left dorsolateral prefrontal cortex (L-DLPFC) of healthy human subjects. We wanted to examine whether lorazepam administration would result in significant changes in the levels of 1H-MRS metabolites in this brain region. Ten healthy controls underwent a short echo-time 1H-MRS session immediately before, and a second one 1 h after lorazepam administration (2mg/orally). The measured 1H-metabolites included N-acetyl-aspartate, phosphocreatine+creatine, trimethylamines, myo-inositol, glutamate, and glutamine, which were expressed as absolute values and ratios. No significant differences were found after lorazepam administration for any of the measured metabolite levels or ratios (paired t-tests, p >.05). This study demonstrated that lorazepam can potentially be utilized to acutely sedate psychiatric subjects during in vivo 1H-MRS sessions, as it does not appear to produce significant changes in the 1H-MRS spectra in this specific brain region

MRI investigation of temporal lobe structures in bipolar patients

Previous anatomical MRI studies have suggested abnormalities in amygdala volumes in bipolar disorder, whereas hippocampus, temporal lobe (TL), and superior temporal gyri (STG) measures have been reported to be normal. This study further investigated the existence of anatomical abnormalities in these brain structures in bipolar subjects, to attempt to replicate previously reported findings. Twenty-four DSM-IV bipolar patients (mean age+/-S.D.=35+/-10 years) and 36 healthy controls (mean age+/-S.D.=37+/-10 years) were studied. 3D SPGR images were obtained with a 1.5T-GE Signa magnet (TR=25 ms, TE=5 ms, FOV=24 cm, slice-thickness=1.5 mm, matrix-size=256 x 192). Volumetric measurements of TL, hippocampus, amygdala, and STG were performed blindly, with a semi-automated software. Bipolar patients had significantly larger left amygdala volumes compared with controls (mean volumes+/-S.D.=2.57+/-0.69 vs. 2.17+/-0.58 ml, respectively; ANCOVA, age, gender, ICV as covariates; F=4.42, df=1/55, P=0.04). The volumes of the other temporal lobe structures did not differ significantly between the two groups (ANCOVA, age, gender, and ICV as covariates, P>0.05). Our findings of enlarged left amygdala in bipolar patients are in agreement with prior MRI studies, suggesting that abnormalities in this brain structure may be implicated in pathophysiology of the illness. Longitudinal studies in high-risk offspring and first-episode patients will be needed to examine whether such abnormalities precede the appearance of symptoms, or whether they may appear subsequently as a result of illness course

Anatomical MRI study of basal ganglia in bipolar disorder patients

This study examined possible anatomical abnormalities in basal ganglia structures in bipolar disorder patients. Caudate and putamen gray matter volumes, and globus pallidus total volume were measured with magnetic resonance imaging (MRI) in 22 DSM-IV bipolar patients (age+/-S.D.=36+/-10 years; eight drug-free and 14 lithium monotherapy patients) and 22 matched healthy control subjects (age+/-S.D.=38+/-10 years). No significant differences were found between bipolar patients and healthy control subjects for any of the basal ganglia measures (t-tests, P>0.05). Age was inversely correlated with left putamen volumes in patients (R=-0.44, P=0.04), but not in healthy control subjects (R=-0.33, P=0.14). Older patients (>36 years old) had a significantly larger left globus pallidus than younger ones (0.05). In conclusion, our findings indicate that the basal ganglia may be anatomically preserved in bipolar patients. This is in contrast to available findings for unipolar disorder. However, our findings also suggest that age and length of illness may have significant effects on basal ganglia structures in bipolar patients, which may be more pronounced among bipolar I patients, and of relevance for the pathophysiology of the disorder

Anatomical MRI study of subgenual prefrontal cortex in bipolar and unipolar disorder patients

This study attempted to replicate previous findings of decreased gray matter content in the subgenual prefrontal cortex (SGPFC) in mood disorder patients. Eighteen DSM-IV unipolar patients, 27 DSM-IV bipolar patients, and 38 healthy controls were studied. A 1.5T GE Signa Imaging System with Signa 5.4.3 software was used. The semi-automated software MedX (Sensor Systems, Sterling, VA) was utilized for the anatomical measures of SGPFC volumes. There were no significant differences in SGPFC volumes in familial and non-familial unipolar and bipolar patients compared with healthy controls, nor between drug-free and lithium-treated bipolar patients (ANOVA, p >.05). In vivo abnormalities in the volumes of SGPFC were not identified in mildly depressed or euthymic unipolar or bipolar mood disorder outpatients, either familial or non-familial

Encounter of a racially mixed group with stressful situations

This conceptual article focuses on the dynamics of ethnically/racially mixed groups in the encounter with a highly stressful situation. To inform the understanding of groups at the intersection of stress and racially mixed group composition, stress and group work literature is critically reviewed and analyzed. Anchored in theoretical, clinical and empirical literature about small groups as microcosms of societal structure and power relationships, specifically as it relates to race and ethnicity, group processes that occur when an ethnically/racially mixed group experiences a stressful event are discussed.The challenges that such an experience poses to the group are presented and illustrated by the use of anecdotal examples from the author’s national and international experience as a social work practitioner, educator and trainer. Implications for practice and directions for future research are offered