White matter hyperintensity signals in psychiatric and nonpsychiatric subjects

Towards an understanding of the pathological basis of senile depression and incident dementia: Implications for treatment

Senile depression (SD) is a heterogeneous syndrome. Several clinical profiles are more likely to appear in SD than in early-life depression, but it remains unclear whether the pathophysiology is different. The prevalence of dementia increases with aging, and the underlying pathophysiological processes in the preclinical phase begin even before cognitive deficits or neurological signs appear. SD may be either a risk factor for developing dementia or a prodromal stage of dementia. The inconsistent findings regarding the association between SD and incident dementia may be attributable to the neuropathological heterogeneity underlying SD. Most studies have focused on patients with the clinical diagnosis of Alzheimer disease (AD) as an outcome, but several clinicopathological studies suggest that primary age-related tauopathy and argyrophilic grain disease may account for a proportion of cases clinically misdiagnosed as AD in the elderly population. Furthermore, most AD cases have additional neuropathologic changes such as cerebrovascular disease and Lewy body disease. Here, we review the neuropathological findings linking SD to incident dementia, focusing on common age-related neuropathologies. In particular, the roles of disturbance of neural circuity, imbalance of monoaminergic systems, dysregulation of the hypothalamic-pituitary-adrenal axis, and elevated neuroinflammatory status are discussed. Finally, we review the current treatment of SD in the context of age-related neuropathological changes.

Behavioral Disturbances in Dementia and Beyond: Time for a New Conceptual Frame?

Alzheimer’s disease and vascular dementia are estimated to be the most common causes of dementia, although mixed dementia could represent the most prevalent form of dementia in older adults aged more than 80 years. Behavioral disturbances are common in the natural history of dementia. However, so far, there is a paucity of studies that investigated the causal association between behavioral psychological symptoms of dementia and dementia sub-types, due to the high heterogeneity of methodology, study design and type of clinical assessment. To understand the scant evidence on such a relevant clinical issue, it could be hypothesized that a new shifting paradigm could result in a better identification of the relationship between behavioral disturbances and dementia. This narrative review provides an update of evidence on the behavioral patterns associated with different dementia sub-types and offers a potential future perspective as common ground for the development of new translational studies in the field of behavioral disturbances in dementia and the appropriateness of psychoactive treatments.

Confining the Concept of Vascular Depression to Late-Onset Depression: A Meta-Analysis of MRI-Defined Hyperintensity Burden in Major Depressive Disorder and Bipolar Disorder

Background: The vascular depression hypothesis emphasizes the significance of vascular lesions in late-life depression. At present, no meta-analytic model has investigated whether a difference in hyperintensity burden compared to controls between late-life and late-onset depression is evident. By including a substantial number of studies, focusing on a meaningful outcome measure, and considering several moderating and control variables, the present meta-analysis investigates the severity of hyperintensity burden in major depressive disorder (MDD) and bipolar disorder (BD). A major focus of the present meta-analysis refers to the role of age at illness onset. It is analyzed whether late-onset rather than late-life depression characterizes vascular depression. Method: In total, 68 studies were included in the meta-analysis and a multilevel random effects model was calculated using Hedges' g as the effect size measure. Results: The severity of hyperintensity burden was significantly greater in the patient group compared to the control group. This effect was evident regarding the whole patient group (g = 0.229) as well as both depression subgroups, with a significantly greater effect in BD (g = 0.374) compared to MDD (g = 0.189). Hyperintensity burden was more pronounced in late-onset depression than in early-onset depression or late-life depression. A considerable heterogeneity between the included studies was observed, which is reflected by the large variability in effects sizes. Conclusion: In conclusion, the present meta-analysis underscores the association of hyperintensities with MDD and BD. Especially late-onset depression is associated with an increased hyperintensity burden, which is in line with the vascular depression hypothesis. The results suggest that it might be more feasible to confine the concept of vascular depression specifically to late-onset depression as opposed to late-life depression. Further research is needed to understand the causal mechanisms that might underlie the relation between hyperintensity burden and depression.

Structural and functional MRI correlates of T2 hyperintensities of brain white matter in young neurologically asymptomatic adults

OBJECTIVES

Although white matter hyperintensities (WMHs) are quite commonly found incidentally, their aetiology, structural characteristics, and functional consequences are not entirely known. The purpose of this study was to quantify WMHs in a sample of young, neurologically asymptomatic adults and evaluate the structural and functional correlations of lesion load with changes in brain volume, diffusivity, and functional connectivity.

METHODS

MRI brain scan using multimodal protocol was performed in 60 neurologically asymptomatic volunteers (21 men, 39 women, mean age 34.5 years). WMHs were manually segmented in 3D FLAIR images and counted automatically. The number and volume of WMHs were correlated with brain volume, resting-state functional MRI (rs-fMRI), and diffusion tensor imaging (DTI) data. Diffusion parameters measured within WMHs and normally appearing white matter (NAWM) were compared.

RESULTS

At least 1 lesion was found in 40 (67%) subjects, median incidence was 1 lesion (interquartile range [IQR] = 4.5), and median volume was 86.82 (IQR = 227.23) mm³. Neither number nor volume of WMHs correlated significantly with total brain volume or volumes of white and grey matter. Mean diffusivity values within WMHs were significantly higher compared with those for NAWM, but none of the diffusion parameters of NAWM were significantly correlated with WMH load. Both the number and volume of WMHs were correlated with the changes of functional connectivity between several regions of the brain, mostly decreased connectivity of the cerebellum.

CONCLUSIONS

WMHs are commonly found even in young, neurologically asymptomatic adults. Their presence is not associated with brain atrophy or global changes of diffusivity, but the increasing number and volume of these lesions correlate with changes of brain connectivity, and especially that of the cerebellum.

KEY POINTS

• White matter hyperintensities (WMHs) are commonly found in young, neurologically asymptomatic adults. • The presence of WMHs is not associated with brain atrophy or global changes of white matter diffusivity. • The increasing number and volume of WMHs correlate with changes of brain connectivity, and especially with that of the cerebellum.

Cerebral White Matter Hyperintensities and Microbleeds in Acute Ischemic Stroke: Impact on Recanalization Therapies. A Review of the Literature

Cerebral white matter hyperintensities (WMH) and cerebral microbleeds (CMBs) are frequently seen on brain imaging acquired for acute ischemic stroke. Given the raising use of recanalization therapies - both intravenous and endovascular - the interest on the impact of WMH and CMBs on the risk of intracerebral hemorrhage and on functional outcome is growing. In this review, we will discuss the relevance of WMH and CMBs among patients with an acute ischemic stroke, focusing on the implications for recanalization therapies.

Exome-sequencing in a large population-based study reveals a rare Asn396Ser variant in the LIPG gene associated with depressive symptoms

Despite a substantial genetic component, efforts to identify common genetic variation underlying depression have largely been unsuccessful. In the current study we aimed to identify rare genetic variants that might have large effects on depression in the general population. Using high-coverage exome-sequencing, we studied the exonic variants in 1265 individuals from the Rotterdam study (RS), who were assessed for depressive symptoms. We identified a missense Asn396Ser mutation (rs77960347) in the endothelial lipase (LIPG) gene, occurring with an allele frequency of 1% in the general population, which was significantly associated with depressive symptoms (P-value=5.2 × 10^-08, β=7.2). Replication in three independent data sets (N=3612) confirmed the association of Asn396Ser (P-value=7.1 × 10^-03, β=2.55) with depressive symptoms. LIPG is predicted to have enzymatic function in steroid biosynthesis, cholesterol biosynthesis and thyroid hormone metabolic processes. The Asn396Ser variant is predicted to have a damaging effect on the function of LIPG. Within the discovery population, carriers also showed an increased burden of white matter lesions (P-value=3.3 × 10^-02) and a higher risk of Alzheimer's disease (odds ratio=2.01; P-value=2.8 × 10^-02) compared with the non-carriers. Together, these findings implicate the Asn396Ser variant of LIPG in the pathogenesis of depressive symptoms in the general population.

Neuropsychological and neuroimaging evidence for the involvement of the frontal lobes in depression: 20 years on

In 1997, neuropsychological and neuroimaging evidence supported the involvement of the frontal lobes and indeed the brain in depression. This was a challenge to conventional phenomenology and linked with the imperative to use neuroscience to understand major mental illness. Since that time, we are seeing ever more convincing evidence for the genetic basis of mental illness (including depression), relevant abnormality in grey and white matter and neuropsychological analysis of brain function. It has proved more difficult to pin down structural abnormality in major depression at the cellular level, but a focus on glial cells is increasingly justified by the evidence. Neuroscience continues to be a buttress against anti-scientific impulses in psychiatry and can help attract young people to enter it as a profession.

Anxiety and depression-Important psychological comorbidities of COPD

Anxiety and depression are common and important comorbidities in patients with chronic obstructive pulmonary disease (COPD). The pathophysiology of these psychological comorbidities in COPD is complex and possibly explained by common risk factors, response to symptomatology and biochemical alterations. The presence of anxiety and/or depression in COPD patients is associated with increased mortality, exacerbation rates, length of hospital stay, and decreased quality of life and functional status. There is currently no consensus on the most appropriate approach to screening for anxiety and depression in COPD. Treatment options include psychological [relaxation, cognitive behavioural therapy (CBT), self-management] and pharmacological interventions. Although there is some evidence to support these treatments in COPD, the data are limited and mainly comprised by small studies. Pulmonary rehabilitation improves anxiety and depression, and conversely these conditions impact rehabilitation completion rates. Additional high quality studies are urgently required to optimise screening and effective treatment of anxiety and depression in patients with COPD, to enhance complex chronic disease management for these patients.

Cerebral white matter lesions and perceived cognitive dysfunction: the role of pregnancy

OBJECTIVE

Women who suffered eclampsia or preterm preeclampsia are twice as likely to demonstrate cerebral white matter lesions (WML) on magnetic resonance imaging compared with age-matched women who had normotensive pregnancies, and they report more cognitive dysfunctions in everyday life. We aimed to determine whether pregnancy in and of itself has a relationship with the presence of WML and subjective cognitive dysfunction.

STUDY DESIGN

Eighty-one parous women who had a normotensive pregnancy were matched for age with 65 nulliparous women and all underwent cerebral magnetic resonance imaging. Presence of cerebral WML was rated and blood pressure was measured. Subjective cognitive functioning was assessed using the Cognitive Failures Questionnaire.

RESULTS

There was no difference in the presence (22% vs 19%) of WML between parous and nulliparous women. Age was a predictor for the presence of WML, whereas the presence of current hypertension was not. Average score on the Cognitive Failures Questionnaire was not different between both groups, nor related to WML.

CONCLUSION

A history of pregnancy in and of itself is not related to the presence of cerebral WML and the perception of cognitive dysfunction. Because of the relationship with preterm preeclampsia and eclampsia, future research should focus on the clinical importance and development throughout the years of such cerebral WML in young women and focus on risk factors for cardiovascular disease.

White matter alterations in antipsychotic- and mood stabilizer-naïve individuals with bipolar II/NOS disorder

Structural magnetic resonance imaging (MRI) studies using voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) have been inconsistent in demonstrating impairments in gray matter (GM) and white matter (WM) structures in bipolar disorder (BD). This may be a consequence of significant confounding effects of medication, illness history and selection of controls in existing studies. Study of bipolar II or not-otherwise-specified (BD II/NOS) disorder provides a solution to these confounds and a bridge to unipolar cases across the affective spectrum. Thirty-eight euthymic, antipsychotic- and mood stabilizer-naïve young adults (mean age = 20.9 years) with BD II/NOS and 37 age-, cognitive ability- and gender-matched healthy controls (HCs) underwent MRI. Voxel-wise and regional gray matter volume comparisons were conducted using voxel-based morphometry (VBM). Tract-based spatial statistics (TBSS) were used to assess whole-brain WM, as indexed using fractional anisotropy (FA), mean diffusivity (MD), parallel and perpendicular diffusion values. No between-group differences were observed for whole-brain VBM comparisons. By contrast, in comparison to HCs, participants with BD II/NOS had significant widespread reductions in FA and increased MD and perpendicular diffusion values in virtually all the major cortical white matter tracts. These data suggest pathophysiological involvement of WM microstructures - but not GM macrostructures - in high functioning BD II/NOS patients at an early age and before significant clinical adversity has been recorded. We propose that white matter development is a valid candidate target for understanding genetic and environmental antecedents to bipolar disorder and mood disorder more generally.

Biological basis of late life depression

Late life depression (LLD) is an important area of research given the growing elderly population. The purpose of this review is to examine the available evidence for the biological basis of LLD. Structural neuroimaging shows specific gray matter structural changes in LLD as well as ischemic lesion burden via white matter hyperintensities. Similarly, specific neuropsychological deficits have been found in LLD. An inflammatory response is another possible underlying contributor to the pathophysiology of LLD. We review the available literature examining these multiple facets of LLD and how each may affect clinical outcome in the depressed elderly.

Depressive Symptoms and Amygdala Volume in Elderly with Cerebral Small Vessel Disease: The RUN DMC Study

Introduction. Late onset depressive symptoms (LODSs) frequently occur in elderly with cerebral small vessel disease (SVD). SVD cannot fully explain LODS; a contributing factor could be amygdala volume. We investigated the relation between amygdala volume and LODS, independent of SVD in 503 participants with symptomatic cerebral SVD. Methods. Patients underwent FLAIR and T1 scanning. Depressive symptoms were assessed with structured questionnaires; amygdala and WML were manually segmented. The relation between amygdala volume and LODS/EODS was investigated and adjusted for age, sex, intracranial volume, and SVD. Results. Patients with LODS had a significantly lower left amygdala volume than those without (P = 0.02), independent of SVD. Each decrease of total amygdala volume (by mL) was related to an increased risk of LODS (OR = 1.77; 95% CI 1.02–3.08; P = 0.04). Conclusion. Lower left amygdala volume is associated with LODS, independent of SVD. This may suggest differential mechanisms, in which individuals with a small amygdala might be vulnerable to develop LODS.

Structural neuroimaging studies in major depressive disorder. Meta-analysis and comparison with bipolar disorder

CONTEXT

Although differences in clinical characteristics exist between major depressive disorder (MDD) and bipolar disorder (BD), consistent structural brain abnormalities that distinguish the disorders have not been identified.

OBJECTIVES

To investigate structural brain changes in MDD using meta-analysis of primary studies; assess the effects of medication, demographic, and clinical variables; and compare the findings with those of a meta-analysis of studies on BD.

DATA SOURCES

The MEDLINE, EMBASE, and PsycINFO databases were searched for studies from January 1, 1980, to February 2, 2010.

STUDY SELECTION

Two hundred twenty-five studies that used magnetic resonance imaging or x-ray computed tomography to compare brain structure in patients with MDD with that of controls were included in an online database, and 143 that measured common brain structures were selected for meta-analysis.

DATA EXTRACTION

Twenty-five variables, including demographic and clinical data, were extracted from each study, when available. For the meta-analysis, mean structure size and standard deviation were extracted for continuous variables, and the proportion of patients and controls with an abnormality in brain structure was extracted for categorical variables.

DATA SYNTHESIS

Compared with the structure of a healthy brain, MDD was associated with lateral ventricle enlargement; larger cerebrospinal fluid volume; and smaller volumes of the basal ganglia, thalamus, hippocampus, frontal lobe, orbitofrontal cortex, and gyrus rectus. Patients during depressive episodes had significantly smaller hippocampal volume than patients during remission. Compared with BD patients, those with MDD had reduced rates of deep white matter hyperintensities, increased corpus callosum cross-sectional area, and smaller hippocampus and basal ganglia. Both disorders were associated with increased lateral ventricle volume and increased rates of subcortical gray matter hyperintensities compared with healthy controls.

CONCLUSIONS

The meta-analyses revealed structural brain abnormalities in MDD that are distinct from those observed in BD. These findings may aid investigators attempting to discriminate mood disorders using structural magnetic resonance imaging data.

Increased prevalence of white matter hyperintensities in patients with panic disorder

The aim of the current study is to compare the prevalence, severity and location of cerebral white matter hyperintensities (WMH) between patients with panic disorder (PD) and healthy control subjects. Patients with PD (n = 24) and matched healthy control subjects (n = 24) were scanned using a 3.0 Tesla whole-body magnetic resonance scanner. Axial T2-weighted and fluid-attenuated inversion recovery images were acquired and evaluated for the prevalence, severity and location of WMH using the modified composite scale of Fazekas and Coffey and coded separately for deep and periventricular WMH. Logistic regression analyses were used to assess the association between WMH and the diagnosis of PD. A greater severity of total WMH was associated with a diagnosis of PD in a dose-dependent pattern (odds ratio [OR] = 8.8, P = 0.005 for mild WMH; OR = 27.7, P = 0.007 for moderate to severe WMH). Deep WMH, where most group differences originated, were predominantly located in the frontal region of the brain (n = 16 in PD, n = 1 in control). The current report is the first study to report an increased prevalence of WMH in patients with PD.

White matter lesions in euthymic patients with bipolar disorder

OBJECTIVE

We aimed to quantify both load and regional distributions of hyperintensities on magnetic resonance imaging (MRI) in prospectively verified euthymic bipolar patients and matched controls.

METHOD

Cerebral hyperintensities on T2, proton density and fluid-attenuated inversion recovery (FLAIR) MRI were compared between 48 bipolar and 47 control subjects using semi-quantitative rating scales.

RESULTS

Bipolar subjects had more severe frontal deep white matter lesions (DWML). Hyperintensity load was independent of age in bipolar patients but increased with age in controls. Global prevalence and severity of hyperintensities did not differ between groups. Exploratory analysis showed DWML in excess in the left hemisphere in bipolar subjects but not in controls.

CONCLUSION

Findings are consistent with clinical, particularly some neurocognitive, features of bipolar disorder and implicate fronto-subcortical circuits in its neurobiology. They more probably reflect a trait abnormality or illness scar rather than a mood state-dependent finding. Processes other than ageing and vascular factors may underlie their development.

A role for white matter abnormalities in the pathophysiology of bipolar disorder

Bipolar disorder is a chronically disabling psychiatric disorder characterized by manic states that is often interspersed with periods of depression whose neurobiology remains largely unknown. There is, however, increasing evidence that white matter (WM) abnormalities may play an important role in the neurobiology of the disorder. In this review we critically evaluate evidence for WM abnormalities in bipolar disorder obtained from neuroimaging, neuropathological, and genetic research. Increased rates of white matter hyperintensities, regional volumetric abnormalities, abnormal water diffusion along prefrontal-subcortical tracts, fewer oligodendrocytes in prefrontal WM, and alterations in the expression of myelin- and oligodendrocyte-related genes are among the most consistent findings. Abnormalities converge in the prefrontal WM and, in particular, tracts that connect prefrontal regions and subcortical gray matter structures known to be involved in emotion. Taken together, the evidence supports and clarifies a model of BD that involves disconnectivity in regions implicated in emotion generation and regulation.

Bipolar and major depressive disorder: neuroimaging the developmental-degenerative divide

Both major depressive disorder and bipolar disorder are the subject of a voluminous imaging and genetics literature. Here, we attempt a comprehensive review of MRI and metabolic PET studies conducted to date on these two disorders, and interpret our findings from the perspective of developmental and degenerative models of illness. Elevated activity and volume loss of the hippocampus, orbital and ventral prefrontal cortex are recurrent themes in the literature. In contrast, dorsal aspects of the PFC tend to display hypometabolism. Ventriculomegaly and white matter hyperintensities are intimately associated with depression in elderly populations and likely have a vascular origin. Important confounding influences are medication, phenotypic and genetic heterogeneity, and technological limitations. We suggest that environmental stress and genetic risk variants interact with each other in a complex manner to alter neural circuitry and precipitate illness. Imaging genetic approaches hold out promise for advancing our understanding of affective illness.

Hyperintense MRI lesions in bipolar disorder: A meta-analysis and review

BACKGROUND

Cortical and subcortical hyperintensities in magnetic resonance imaging (MRI) scans are thought to represent areas of ischemic damage to brain tissue. Researchers have focused on the possible role these lesions may have in psychiatric disorders, including bipolar disorder. In 1997, the proposed 'vascular mania' diagnosis suggested utilizing not only the presence of strokes, but also confluent hyperintensities in its diagnostic criteria. This study was conducted to use meta-analytic techniques to investigate the association of hyperintensities and bipolar illness and to evaluate the current state of the literature.

METHODS

Using the PubMed and MEDLINE databases, we conducted a systematic literature search of studies investigating hyperintensities in subjects with bipolar disorder and controls or other psychiatric illnesses. We identified 44 publications from which 35 studies were included for review and 27 were selected for meta-analysis. Summary statistics of the prevalence were estimated through odds-ratios and confidence interval. Heterogeneity of the results across studies was tested using Q-statistics.

RESULTS

Meta-analysis identified an odds ratio of 2.5 (95% CI 1.9, 3.3) for hyperintensities in bipolar subjects compared to controls; however, there was significant heterogeneity among the studies (Q-statistics = 32; p = 0.04). This finding was most prominent for adolescents and children where the odds ratio was 5.7 (95% CI 2.3, 13.7). Deep white matter hyperintensities (odd ratio 3.2; 95% CI 2.2, 4.5) and subcortical grey matter hyperintensities (odds ratio 2.7; 95% CI 1.3, 2.9) were more strongly associated with bipolar subjects. There were no differences between bipolar subjects and controls for perivascular hyperintensities (odds ratio 1.3; 95% CI 0.8, 1.9). Though hyperintensities were numerically greater in bipolar subjects, meta-analysis did not demonstrate any significant differences between bipolar subjects and unipolar depression subjects (OR 1.6; 95% CI 0.9, 2.7) nor subjects with schizophrenia (OR 1.5; 95% CI 0.9, 2.7).

CONCLUSIONS

This meta-analysis continues to support the association of bipolar disorder and hyperintensities, especially in the deep white matter and subcortical grey matter. It also highlights the increased incidence in children and adolescence with bipolar disorder. However, hyperintensities are not specific to bipolar disorder, but appear at similar rates in unipolar depression and schizophrenia. Thus, the role of hyperintensities in the pathogenesis, pathophysiology, and treatment of bipolar disorder remains unclear. Further studies are required that are large enough to decrease the heterogeneity of the samples and MRI techniques, assess size and location of hyperintensities, and the impact on treatment response. Coordination with newer imaging techniques, such as diffusion tensor imaging (DTI) may be especially helpful in understanding the pathology of these lesions.

Periventricular white matter hyperintensities as predictors of suicide attempts in bipolar disorders and unipolar depression

The aim of this study was to evaluate whether deep white matter hyperintensities (DWMH) and periventricular white matter hyperintensities (PVH) are associated with suicidal behavior in patients with major affective disorders. Subjects were 99 consecutively admitted inpatients (42 men; 57 women; mean age: 46.5 years [SD=15.2; Min./Max.=19/79]) with a diagnosis of major affective disorder (bipolar disorder type I, bipolar disorder type-II and unipolar major depressive disorder). 44.4% of the participants had made at least one previous suicide attempt. T2-weighted brain magnetic resonance images were rated for the presence and extension of WMH using the modified Fazekas scale. Patients were interviewed for clinical data on average 5 days after admission. Bivariate analyses, corrected for multiple-testing, and logistic regression analysis were used to test the association between suicide attempts and clinical variables. Attempters and nonattempters differed only in the presence of PVH--the former were more likely to have PVH. The logistic regression indicated that the presence of PVH was robustly associated with suicidal behaviors after controlling for age (OR: 8.08). In conclusion, neuroimaging measures may be markers of risk for suicidal attempts in patients with major affective disorders.

White-matter hyperintensities in first-episode psychosis

BACKGROUND

White-matter hyperintensities have been associated with both schizophrenia and mood disorders, particularly bipolar disorder, but results are inconsistent across studies.

AIMS

To examine whether white-matter hyperintensities are a vulnerability marker for psychosis or are specifically associated with bipolar disorder.

METHOD

T(2)-weighted magnetic resonance imaging data were acquired in 129 individuals with first-episode psychosis (either affective or non-affective psychoses) and 102 controls who were randomly selected from the same geographical areas. Visual white-matter hyperintensity ratings were used for group and subgroup comparisons.

RESULTS

There were no statistically significant between-group differences in white-matter hyperintensity frequency or severity scores. No significant correlations were found between white-matter hyperintensity scores and duration of illness, duration of untreated psychosis, or severity of psychotic, manic or depressive symptoms.

CONCLUSIONS

White-matter hyperintensities are not associated with vulnerability to psychosis in general, or specifically with affective psychoses. Further, first-episode psychosis investigations using more quantitative methods are warranted to confirm these findings.

Neuroimaging endophenotypes: strategies for finding genes influencing brain structure and function

It is vitally important to identify the genetic determinants of complex brain-related disorders such as autism, dementia, mood disorders, and schizophrenia. However, the search for genes predisposing individuals to these illnesses has been hampered by their genetic and phenotypic complexity and by reliance upon phenomenologically based qualitative diagnostic systems. Neuroimaging endophenotypes are quantitative indicators of brain structure or function that index genetic liability for an illness. These indices will significantly improve gene discovery and help us to understand the functional consequences of specific genes at the level of systems neuroscience. Here, we review the feasibility of using neuroanatomic and neuropsychological measures as endophenotypes for brain-related disorders. Specifically, we examine specific indices of brain structure or function that are genetically influenced and associated with neurological and psychiatric illness. In addition, we review genetic approaches that capitalize on the use of quantitative traits, including those derived from brain images.

Current perspectives on management of co-morbid depression in COPD

Individuals with COPD have a higher prevalence of co-morbid depression than either the general population or patients with other chronic illnesses. The best estimates report a prevalence of approximately 40% in COPD patients, compared to 15% in the general population. Depression in COPD patients leads to a lower quality of life, greater objective impairment in function, and decreased adherence to therapeutic interventions. While many depressed COPD patients have been treated empirically with antidepressants--subjecting them to antidepressant side effects, toxicities, and costs--there is a surprising lack of evidence supporting or directing that treatment. We review the current literature regarding the management of depression in COPD, suggest strategies for management, and future research needs.

Prevalence of White Matter Hyperintensities in a Young Healthy Population

BACKGROUND AND PURPOSE

White matter hyperintensities (WMHs) are bright objects observed in the white matter on brain magnetic resonance (MR) imaging. WMHs are often reported as "normal" findings but may represent pathological changes. The prevalence of WMHs appears to increase with increasing age although both the typical timing and clinical significance of their appearance among medically and neurologically healthy persons remains unclear. We assessed the prevalence of WMHs in a cohort of younger healthy subjects.

METHODS

Our study comprised 243 healthy subjects ages 16-65 years from our prospective normative MR imaging database. MR scans were rated for presence of periventricular and centrum semiovale WMHs using a four-point visual semi-quantitative scale.

RESULTS

WMHs occurred in 5.3% (13 of 243) of subjects. All WMHs were small (rating of 0.5) except one subject age 65 years who had large WMHs (ratings of 2). The median age for subjects with no WMHs was 34.5 years compared to 57.0 years for subjects with WMHs. There were no gender differences (P= .76). Older age correlated with presence of WMHs (r = 0.24; P= .01). Age greater than 55 years had a 10-fold increase in the prevalence of WMHs compared to age < or =55 years (odds ratio = 10.01; 95% confidence interval = 3.1-32.3; P < .001).

CONCLUSION

WMHs were uncommon in a younger healthy population screened for comorbid diseases, but increased 10-fold in subjects over 55 years of age. When present, the WMHs are generally small (rating of 0.5). While large WMHs appear to be associated with cognitive deterioration, the optimum threshold for identification, clinical significance, and prognostic value of smaller white matter changes requires further research.

Prevalence and impact of depression in chronic obstructive pulmonary disease patients

PURPOSE OF REVIEW

This review presents recent advances in the study of the depression that is so often co-morbid with chronic obstructive pulmonary disease. The discussion includes prevalence, etiology, impact and management.

RECENT FINDINGS

Efforts continue to find a reliable prevalence rate for co-morbid depression in patients with chronic obstructive pulmonary disease but studies regularly find depression in 20-60% of these patients. Multiple etiologies contribute to this elevated rate including genetic predisposition, grief reaction, and effects of chronic obstructive pulmonary disease on the central nervous system. Once depression develops patients are less adherent to treatment plans, lose function and, potentially, suffer worse outcomes in exacerbations. Management of depression in chronic obstructive pulmonary disease continues to be primarily empirical. There are few quality studies demonstrating the usefulness of antidepressants in this population. Some studies suggest selective serotonin reuptake inhibitors will be effective, but require replication in larger groups. Other interventions including psychotherapy, physical rehabilitation, and improved social support are accumulating supporting data, but further research is needed.

SUMMARY

Depression is present in up to 60% of patients with chronic obstructive pulmonary disease. It jeopardizes patients' ability to utilize treatment and may increase their risk for poor outcomes. Effective management will require high-quality studies and a multidisciplinary approach.

T2 Hyperintensities in Bipolar Patients and their Healthy Siblings

BACKGROUND

This study investigates the frequency of hyperintensities, which are common in bipolar disorder, in sufferers' siblings who are free of bipolar disorder and to ascertain whether these lesions reflect any familial characteristics. It offers an assessment of the relationship between these lesions and clinical characteristics.

METHODS

The study group consisted of 12 patients with bipolar disorder, their siblings who had no history of mental disorder, and a matched control group. All three groups were assessed using SCID-I (Structured Clinical Interview for DSM-IV Axis I Disorders) for diagnosis, and MRI (magnetic resonance imaging) for signal hyperintensity.

RESULTS

No periventricular white matter lesions were encountered in any groups. It was found that in the patients and siblings, the location was in the right cerebral hemisphere in the deep white matter, whereas it was in the left cerebral hemisphere for the control group. Only in the patient group were lesions detected in subcortical white matter in the right cerebral hemisphere. The lesions were localized in the fronto-parietal area. Considering the brain as a whole, more hyperintensities were detected in the patient group compared to the other two groups. The onset of the disorder with a manic episode was increasing probably in the presence of hyperintensities.

CONCLUSIONS

Despite being alike in terms of age, more hyperintensities were detected in the patient group than in the siblings and control groups. Contrary to the control group, however, hyperintensities were localized in the right cerebral hemisphere in both the patients and the siblings groups. Hyperintensities seen in the left cerebral hemisphere yield a nonspecific impression. Siblings who have hyperintensities in the right cerebral hemisphere should be followed up and investigated with regard to bipolar disorder.

Cortical magnetic resonance imaging findings in familial pediatric bipolar disorder

BACKGROUND

Morphometric magnetic resonance imaging (MRI) studies of pediatric bipolar disorder (BD) have not reported on gray matter volumes but have reported increased lateral ventricular size and presence of white matter hyperintensities (WMH). We studied gray matter volume, ventricular-to-brain ratios (VBR), and number of WMH in patients with familial, pediatric BD compared with control subjects.

METHODS

Twenty subjects with BD (aged 14.6 +/- 2.8 years; 4 female) according to the Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia, each with a parent with BD, and 20 age-, gender-, and intelligence quotient-matched healthy control subjects (aged 14.1 +/- 2.8 years; 4 female) were scanned at 3 T. Most subjects were taking psychotropic medications. A high-resolution T1-weighted spoiled gradient echo three-dimensional MRI sequence was analyzed by BrainImage for volumetric measurements, and T2-weighted images were read by a neuroradiologist to determine presence of WMH.

RESULTS

After covarying for age and total brain volume, there were no significant differences between subjects with BD and control subjects in volume of cerebral (p = .09) or prefrontal gray matter (p = .34). Subjects with BD did not have elevated numbers of WMH or greater VBR when compared with control subjects.

CONCLUSIONS

Children and adolescents with familial BD do not seem to have decreased cerebral grey matter or increased numbers of WMH, dissimilar to findings in adults with BD. Gray matter decreases and development of WMH might be later sequelae of BD or unique to adult-onset BD.

Magnetic resonance findings in bipolar disorder

The MR findings reviewed in this article suggest structural, chemical, and functional abnormalities in specific brain regions participating in mood and cognitive regulation, such as the DLPFC, anterior cingulate, amygdala,STG, and corpus callosum in subjects with bipolar disorder. These abnormalities would represent an altered anterior-limbic network disrupting inter- and intrahemispheric communication and underlying the expression of bipolar disorder. Available studies are limited by several confounding variables, such as small and heterogeneous patient samples, differences in clinical and medication status, and cross-sectional design. It is still unclear whether abnormalities in neurodevelopment or neurodegeneration play a major role in the pathophysiology of bipolar disorder. These processes could act together in a unitary model of the disease, with excessive neuronal pruning/apoptosis during childhood and adolescence being responsible for the onset of the disorder and subsequent neurotoxic mechanisms and impaired neuroplasticity and cellular resilience being responsible for further disease progression. Future MR studies should investigate larger samples of first-episode drug-free patients, pediatric patients, subjects at high risk for bipolar disorder, and unaffected family members longitudinally. Such a study population is crucial to examine systematically whether brain changes are present before the appearance of symptoms (eg, maldevelopment) or whether they develop afterwards, as a result of illness course (eg, neurodegeneration). These studies will also be instrumental in minimizing potentially confounding factors commonly found in adult samples, such as the effects of long-term medication, chronicity, and hospitalizations. Juvenile bipolar patients often have a strong family history of bipolar disorder. Future studies could help elucidate the relevance of brain abnormalities as reflections of genetic susceptibility to the disorder. MR studies associated with genetic, post-mortem, and neuropsychologic studies will be valuable in separating state from trait brain abnormalities and in further characterizing the genetic determinants, the neuropathologic underpinnings, and the cognitive disturbances of bipolar disorder.

Brain function and structure in adults with attention-deficit/hyperactivity disorder

Cross-sectional data suggest that brain dysfunctions are a central component of attention-deficit/hyperactivity disorder (ADHD) in children, and a growing literature is suggesting the same for adults. This article reviews the current state of the literature pertaining to the structural and functional brain abnormalities that are found in adults with ADHD. Because the literature on ADHD in children is more extensive than that reported heretofore in ADHD in adults,the authors include brief summaries of the child literature to help inform that found in adults.

Mood disorders - review of structural MRI studies

BACKGROUND

Mood disorders are related to considerable morbidity and mortality, and although there is little doubt that they are brain-based disorders, their neural correlates still remain elusive. A neuro-anatomic model of mood regulation comprising the prefrontal cortex, amygdala-hippocampus complex, thalamus, basal ganglia, and connections among these areas has been proposed.

OBJECTIVE

We reviewed the evidence for regional brain abnormalities in bipolar disorder, and attempted to integrate available findings into a comprehensive pathophysiological model of illness.

METHODS

A computerized Medline Ovid search was conducted for the period 1966-2002, and complemented by a manual search of bibliographical references from recent reviews. Articles meeting specified criteria were included.

RESULTS

Hyperintense lesions in cortical and subcortical regions are the most consistently reported and widely studied structural abnormalities. Smaller prefrontal cortical volume is a common finding in bipolar disorder and unipolar depression. Enlarged amygdala (in bipolar disorder) and smaller hippocampus (in unipolar depression) have been reported by several groups. Decreased volumes (in unipolar depression) and increased or unaltered volumes (in bipolar disorder) of striatal structures have been reported.

CONCLUSIONS

Bipolar and unipolar mood disorders are associated with detectable structural brain abnormalities. The histopathology underlying such anatomical changes remains to be elucidated. To reach more definitive conclusions about neuroanatomical changes that take place during the course of mood disorders, prospective longitudinal studies are needed. Also, integration with functional imaging is necessary in order to elucidate the relevance of identified structural abnormalities.

Neuroimaging studies of mood disorder effects on the brain

Studies of early-onset recurrent depression, late life depression associated with neurologic disorders, and bipolar illness have revealed structural brain changes within a neuroanatomical circuit. This circuit, originally described by, has been termed the limbic-cortical-striatal-pallidal-thalamic tract and is comprised of structures which are extensively interconnected. In three-dimensional magnetic resonance imaging studies of affective illness, many of the structures that comprise this tract have been found to have volume loss or structural abnormalities. Mechanisms proposed to explain volume loss in depression include glucocorticoid neurotoxicity, decreased brain-derived growth factor, decreased neurogenesis, and loss of plasticity.

Diabetes, the brain, and behavior: is there a biological mechanism underlying the association between diabetes and depression?

In summary, our review of the literature suggests that diabetes, especially type 1 diabetes, may place patients at risk for a depressive disorder through a biological mechanism linking the metabolic changes of diabetes to changes in brain structure and function. Further studies are warranted examining these relationships in order to better understand the impact of diabetes on brain functioning and structure as well as one potential manifestation of such changes--affective disorder. Moreover, such studies could play a useful role in better understanding mechanisms that commonly underlie the development of depression in individuals without diabetes but with other medical problems or conditions.

Deep white matter hyperintensities in patients with bipolar depression, unipolar depression and age-matched control subjects

OBJECTIVE

Hyperintensities in the white matter of the brain (DWH) and in the periventricular area (PVH) seen on magnetic resonance imaging (MRI) have been reported to be more frequent in patients with bipolar disorder (BP) than in normal subjects. To examine this further we compared MRI of patients with BP with age-matched patients with major depressive disorder (unipolar depression, UP) and healthy control subjects.

METHODS

T2 weighted axial and coronal brain MRI scans were obtained from 13 patients in the depressive phase of BP, 11 with current UP and 19 age-matched control subjects. The degree of DWH and PVH present in each scan was determined using a standardized scoring method.

RESULTS

The PVH ratings were similar in the three groups of subjects. However, proportionately more BP patients had higher DWH scores than either UP patients or controls. Although this difference did attain statistical significant, a main effect of age was noted. Further, subjects over the age of 50 were under-represented in the UP group.

CONCLUSIONS

Notwithstanding the small total sample size and relative lack of older subjects in the UP group, the fact that almost twice as many BP patients showed more severe DWH suggests that patients with BP may be more vulnerable to develop these changes than UP patients and healthy controls.

Anatomic location and laterality of MRI signal hyperintensities in late-life depression

OBJECTIVES

Evidence is mounting linking cerebrovascular disease with the development of major depression in the elderly. Lesions in both white and gray matter have been associated with geriatric depression. In addition, the literature on poststroke depression suggests that left-sided lesions are associated with depression. We sought to examine the severity and location of white- and gray-matter lesions in a group of elderly depressives and nondepressed control subjects.

METHOD

115 depressed patients (69 with late onset, 46 with early onset) and 37 controls, all over age 45, received magnetic resonance imaging (MRI). Semiquantitative severity ratings and quantitative measurements of number and size of MRI hyperintensities were obtained, and groups were compared using Cochran-Mantel-Haenszel (CMH) analyses and repeated-measures analyses of covariance adjusting for age.

RESULTS

Late-onset depressed patients had more severe hyperintensity ratings in deep white matter than early-onset patients and controls. Late- and early-onset patients had more severe subcortical gray-matter hyperintensities (particularly in the putamen) compared with controls. Left-sided white-matter lesions were significantly associated with older age of depression onset, whereas right-anterior white matter and left-subcortical lesions (particularly in the putamen) were associated with melancholia in the depressed group.

CONCLUSION

These findings extend previous reports of an association between cerebrovascular disease and depression, as well as recent studies showing lateralized lesion involvement in geriatric depression. Such vascular pathology may disrupt neural pathways involved in affective processing and the maintenance of a normal mood and psychomotor state.

Anatomical MRI findings in mood and anxiety disorders

OBJECTIVE

In vivo structural magnetic resonance imaging (MRI) studies have evaluated the brain anatomy of various psychiatric disorders, allowing the investigation of putative abnormal brain circuits possibly involved in the patophysiology of psychiatric disorders. Here we reviewed the structural MRI literature in mood and anxiety disorders.

METHODS

All anatomical MRI studies evaluating mood and anxiety disorder patients were identified through a comprehensive Medline search conducted for the period from 1966 to January 2002, and a manual search of bibliographic cross-referencing complemented the Medline search.

RESULTS

Differential patterns of anatomical brain abnormalities appear to be involved in subtypes of mood disorders, with hippocampus and basal ganglia being abnormal in unipolar disorder, and amygdala and cerebellum in bipolar disorders, suggesting that these two mood disorders are biologically distinct. As for anxiety disorders, orbital frontal regions and basal ganglia have been reported to be anatomically abnormal in obsessive-compulsive disorder, temporal lobe was found to be abnormally reduced in panic disorder, and abnormal hippocampus shrinkage was shown in posttraumatic stress disorder.

CONCLUSIONS

The structural MRI findings reviewed here suggest abnormalities in specific brain regions participating in proposed neuroanatomic models possibly involved in the pathophysiology of mood disorders and anxiety disorders. Nonetheless, available MRI studies have suffered from limitations related to relatively small patient samples and involvement of medicated patients, and were largely cross-sectional investigations. Therefore, longitudinal MRI studies involving more sizeable samples of drug-free patients, patients at first episode of illness or at high risk for mood or anxiety disorders, associated to genetic studies, are likely to be extremely valuable to separate state from trait brain abnormalities and to characterize further the pathophysiology of these disorders.

Increased presence of white matter hyperintensities in adolescent patients with bipolar disorder

Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adult patients with bipolar disorder. We investigated whether this increase was also evident in a group of adolescent patients with bipolar disorder. The sample consisted of 15 bipolar patients, 19 patients with schizophrenia and 16 healthy comparison subjects. All subjects were adolescents. WMH were blindly rated on T2-weighted and PD-weighted MRI scans using our own scale with documented inter-rater reliability. WMH were present in 10 of 15 bipolar patients (67%), seven of 19 patients with schizophrenia (37%) and five of 16 comparison subjects (31%). The bipolar adolescent group had a statistically significant increased presence of WMH compared both with healthy comparison subjects and the schizophrenic group. The association between WMH and bipolar disorder appears to extend to the adolescent years.

Hipersinais subcorticais no exame de ressonância magnética: comparação entre idosos deprimidos e idosos normais

É relatado em alguns estudos que idosos deprimidos apresentam maior frequência de hipersinais ao exame de ressonância magnética do que controles normais. No entanto os indivíduos estudados tinham fatores de risco para doenças cerebrovasculares. Este estudo analisou pacientes com história de depressão maior e indivíduos controles compatíveis, excluindo-se fatores de risco cerebrovasculares, com o objetivo de determinar se indivíduos deprimidos apresentam maior frequência de hipersinais em substância branca e outras lesões. Avaliamos a prevalência e a severidade dos hipersinais à ressonância magnética de encéfalo em 30 pacientes idosos deprimidos e 20 controles pareados para a idade. Hipersinais de substância branca profunda, hipersinais periventriculares e hipersinais em substância cinzenta subcortical foram classificados em escala padrão 0-3, por dois radiologistas que desconheciam o diagnóstico clínico. Não foram encontradas diferenças significativas entre os grupos para hipersinais subcorticais. Estes achados sugerem que os fatores de risco cerebrovasculares provavelmente medeiam a relação entre depressão e hipersinais, encontrada em estudos anteriores.

The neuropsychology and neuroanatomy of bipolar affective disorder: a critical review

Bearden CE, Hoffman KM, Cannon TD. The neuropsychology and neuroanatomy of bipolar affective disorder: a critical review. Bipolar Disord 2001: 3: 106 150. C Munksgaard, 2001

OBJECTIVES

To present a comprehensive review of the existing neuropsychological and neuroimaging literature on bipolar affective disorder. This review critically evaluates two common conceptions regarding the neuropsychology of bipolar disorder: 1) that, in contrast to schizophrenia, bipolar affective disorder is not associated with general cognitive impairment independent of illness episodes, and 2) relative right hemisphere (RH) dysfunction is implicated in bipolar illness patients, supported by reports of relatively greater impairment in visuospatial functioning, lateralization abnormalities, and mania secondary to RH lesions.

METHODS

The major computerized databases (Medline and PSYCInfo) were consulted in order to conduct a comprehensive, integrated review of the literature on the neuropsychology and neuroanatomy of bipolar disorder. Articles meeting specified criteria were included in this review.

RESULTS

In a critical evaluation of the above notions, this paper determines that: 1) while there is little evidence for selective RH dysfunction, significant cognitive impairment may be present in bipolar illness, particularly in a subgroup of chronic, elderly or multiple-episode patients, suggesting a possible toxic disease process, and 2) the underlying functional correlate of these cognitive deficits may be white matter lesions ('signal hyperintensities') in the frontal lobes and basal ganglia, regions critical for executive function, attention, speeded information processing, learning and memory, and affect regulation. While this hypothesized neural correlate of cognitive impairment in bipolar disorder is speculative, preliminary functional neuroimaging evidence supports the notion of frontal and subcortical hypometabolism in bipolar illness.

CONCLUSIONS

The etiology of the structural brain abnormalities commonly seen in bipolar illness, and their corresponding functional deficits, remains unknown. It is possible that neurodevelopmental anomalies may play a role, and it remains to be determined whether there is also some pathophysiological progression that occurs with repeated illness episodes. More research is needed on first-episode patients, relatives of bipolar probands, and within prospective longitudinal paradigms in order to isolate disease-specific impairments and genetic markers of neurocognitive function in bipolar disorder.

Cognitive deficits in depression: possible implications for functional neuropathology

BACKGROUND

While depression is known to involve a disturbance of mood, movement and cognition, its associated cognitive deficits are frequently viewed as simple epiphenomena of the disorder.

AIMS

To review the status of cognitive deficits in depression and their putative neurobiological underpinnings.

METHOD

Selective computerised review of the literature examining cognitive deficits in depression and their brain correlates.

RESULTS

Recent studies report both mnemonic deficits and the presence of executive impairment--possibly selective for set-shifting tasks--in depression. Many studies suggest that these occur independent of age, depression severity and subtype, task 'difficulty', motivation and response bias: some persist upon clinical 'recovery'.

CONCLUSIONS

Mnemonic and executive deficits do no appear to be epiphenomena of depressive disorder. A focus on the interactions between motivation, affect and cognitive function may allow greater understanding of the interplay between key aspects of the dorsal and ventral aspects of the prefrontal cortex in depression.

Impact of white matter changes on clinical manifestation of Alzheimer's disease: A quantitative study

BACKGROUND AND PURPOSE

There have been conflicting results involving the clinical significance of white matter changes in patients with Alzheimer's disease (AD). We studied the association between the volume of white matter hyperintensities (WMHs) on T2-weighted images and cognitive, neurological, and neuropsychiatric symptoms.

METHODS

The subjects were 76 AD patients who had WMHs but no obvious cerebrovascular diseases. We quantified the volume of WMHs by using fast-fluid-attenuated inversion recovery images and whole brain atrophy by using 3D spoiled gradient-echo images. Effects of WMHs and brain atrophy on dementia severity, cognitive function, neuropsychiatric disturbances, and neurological findings were examined.

RESULTS

Whole brain atrophy was significantly associated with dementia severity and cognitive disturbances, as well as with grasp reflex and some kinds of neuropsychiatric disturbances. After we controlled for the effects of brain atrophy, duration of symptoms, and demographic factors, we found that WMH volume was not associated with global cognitive disturbances or dementia severity but was significantly associated with urinary incontinence, grasp reflex, and aberrant motor behaviors. Brain atrophy and WMH volume were not significantly correlated either before or after controlling for age, sex, education, and duration of symptoms. WMH volume was associated with hypertension, but brain atrophy was not positively correlated with any vascular risk factors.

CONCLUSIONS

Our results support the hypothesis that WMHs in AD patients are superimposed phenomena of vascular origin. WMHs contribute to specific neurological and neuropsychiatric manifestations but not to global cognitive impairment, which is more closely associated with brain atrophy.

Neuroimaging in bipolar disorder

OBJECTIVE

The authors reviewed neuroimaging studies of bipolar disorder in order to evaluate how this literature contributes to the current understanding of the neurophysiology of the illness.

METHOD

Papers were reviewed as identified, using the NIMH PubMed literature search systems that reported results of neuroimaging studies involving a minimum of five bipolar disorder patients compared with healthy comparison subjects.

RESULTS

Structural neuroimaging studies report mixed results for lateral and third ventriculomegaly. Recent studies suggest subcortical structural abnormalities in the striatum and amygdala, as well as the prefrontal cortex. Proton spectroscopic studies suggest that abnormalities in choline metabolism exist in bipolar disorder, particularly in the basal ganglia. Additionally, phosphorous MRS suggests that there may be abnormalities in frontal phospholipid metabolism in bipolar disorder. Functional studies have identified affective state-related changes in cerebral glucose metabolism and blood flow, particularly in the prefrontal cortex during depression, but no clear abnormalities specific to bipolar disorder have been consistently observed.

CONCLUSIONS

The current literature examining the neurophysiology of bipolar disorder using neuroimaging is limited. Nonetheless, abnormalities in specific frontal-subcortical brain circuits seem likely. Additional targeted studies are needed to capitalize on this burgeoning technology to advance our understanding of the neurophysiology of bipolar disorder.

Affective behavioural disturbances in Alzheimer's disease and ischaemic vascular disease

OBJECTIVES

To investigate affective change in Alzheimer's disease and ischaemic vascular disease and examine the contribution of white matter disease to psychopathology in these dementias. Based on earlier studies, it was predicted that: (1) depression would be more prevalent and severe in ischaemic vascular disease; (2) psychomotor slowing would be more prevalent in ischaemic vascular disease; (3) apathy would be more prevalent in ischaemic vascular disease; and (4) The degree of white matter disease would be positively correlated with the severity of psychomotor slowing.

METHODS

Ratings of affective/behavioural states and white matter disease were compared in 256 patients with Alzheimer's disease and 36 patients with ischaemic vascular disease or mixed dementia with an ischaemic vascular component using analysis of variance (ANOVA) and linear regression models.

RESULTS

The findings were: (1) decreased affect/withdrawal was more prevalent and severe in patients with ischaemic vascular disease and patients with white matter disease; (2) psychomotor slowing was more severe in patients with ischaemic vascular disease and patients with white matter disease; and (3) differences between Alzheimer's disease and ischaemic vascular dementia groups in the degree of psychomotor slowing were independent of the severity of white matter disease.

CONCLUSIONS

Future studies using structural and functional neuroimaging techniques would be helpful for examining the relation between neurobiological factors and affective/behavioural disturbances in dementia.

Qualitative MRI findings in adults with 22q11 deletion syndrome and schizophrenia

BACKGROUND

A genetic syndrome associated with schizophrenia, 22q11 deletion syndrome (22qDS), may represent a genetic subtype of schizophrenia (22qDS-Sz). Structural brain changes are common in schizophrenia and may involve developmental anomalies, but there are no data yet for 22qDS-Sz. The objective of this study was to assess brain structure in adults with 22qDS-Sz using magnetic resonance imaging (MRI).

METHODS

Brain and arterial MRI scans of 11 adults with 22qDS-Sz (mean age = 28.4 years, SD = 6.5) were systematically assessed by a neuroradiologist for qualitative anomalies.

RESULTS

A high frequency of abnormalities were found: T2 white matter bright foci (BF), 90%; developmental midline anomalies, 45%; cerebral atrophy or ventricular enlargement, 54%; mild cerebellar atrophy, 36%; skull base abnormalities, 55%; and minor vascular abnormalities, 36%.

CONCLUSIONS

BF and skull base abnormalities, especially in association with neurodevelopmental midline abnormalities, may be distinguishing MRI features for a genetic subtype of schizophrenia involving a deletion on chromosome 22.

The pathomorphology of schizophrenia and mood disorders: similarities and differences

In this article, post-mortem neurohistological and structural imaging studies of schizophrenia and mood disorders are briefly reviewed. In contrast to the large number of post-mortem studies on schizophrenia published during the last 20 years, very few histological studies of affective disorders are available. After commenting on CT and MRI studies, as well as on neuropathological findings on whole-brain size, cortex, frontal and temporal lobes, limbic system, basal ganglia, thalamus, brain stem, and cortical asymmetry, it is concluded that despite a broad overlap in structural findings in the so-called endogenous psychoses, heteromodal association cortex, limbic system, and structural asymmetry are more affected in schizophrenia, while subtle structural abnormalities in the basal ganglia, especially in the nucleus accumbens and in hypothalamic areas, might play a crucial role in mood disorders.

Structural brain imaging in schizophrenia: a selective review

Structural neuroimaging studies have provided some of the most consistent evidence for brain abnormalities in schizophrenia. Since the initial computed tomography study by Johnstone and co-workers, which reported lateral ventricular enlargement in schizophrenia, advances in brain imaging technology have enabled further and more refined characterization of abnormal brain structure in schizophrenia in vivo. This selective review discusses the major issues and findings in structural neuroimaging studies of schizophrenia. Among these are evidence for generalized and regional brain volume abnormalities, the specificity of anatomic findings to schizophrenia and to men versus women with schizophrenia, the contribution of genetic influences, and the timing of neuroanatomic pathology in schizophrenia. The second section reviews new approaches for examining brain structure in schizophrenia and their applications to studies on the pathophysiology of schizophrenia.

Hyperintense lesions on magnetic resonance images in bipolar disorder

BACKGROUND

To examine the magnetic resonance (MR) images of bipolar patients across a wide age range for the presence of hyperintense lesions compared to age- and gender-matched control subjects.

METHODS

Consecutive admissions to a mood disorders unit over a 2-year period were evaluated retrospectively for the presence of bipolar disorder by DSM-III-R criteria and whether they received an MR scan. Bipolar patients (n = 70, mean age = 49.9 +/- 19.7 years) were age- and gender-matched to control subjects (n = 70, mean age = 53.2 +/- 18.1 years) and the MR scans were rated to assess for the presence of hyperintensites.

RESULTS

Compared to control subjects, the bipolar patients demonstrated hyperintense lesions in the subependymal region, subcortical gray nuclei, and the deep white matter.

CONCLUSIONS

Hyperintense lesions in bipolar patients are found in both the subcortical white matter and gray nuclei and may play an important role in the etiology of bipolar illness.

Neuroimaging in psychiatry

The promise of neuroimaging as an aid to diagnosis is discussed, and findings from the most accessible imaging techniques are reviewed. In addition, some of the earliest findings from functional MR imaging and other technologies are presented with several illustrations. Strategies for interpretation, critique of imaging techniques, and review of major findings for brain injury, mood, anxiety, schizophrenia, and attention deficit disorders are offered. Examples of normal and pathologic images illustrate actual cases and examples of the newer imaging technologies.

Major depression and the basal ganglia

In the last decade, major changes in our understanding of basal ganglia functions have occurred. Traditionally the basal ganglia were considered to be involved only in the modulation of movement. Recent research has suggested that the basal ganglia also take part in complex fronto-subcortical networks that have an important role in cognition reward, and mood regulation. The authors review recent findings that implicate basal ganglia abnormalities in the pathophysiology of mood disorders and discuss their potential implications for future developments in the pharmacotherapy of depressive disorder.

Structural changes in the brain of patients with bipolar affective disorder by MRI: a review of the literature

1. Current literature was searched to evaluate the use of magnetic resonance imaging in patients with bipolar disorder. 2. The presence of white matter hyperintensities, differences in temporal lobe and hippocampal structures, and ventricular enlargement in patients with bipolar disorder was assessed. 3. Further use of MRI in patients with bipolar disorder is reviewed.