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

Poststroke depression: importance of its detection and treatment

BACKGROUND

Poststroke depression (PSD) is a complication that occurs in up to 30% of the patients who have had a stroke. Its development is associated with a poor functional prognosis and a negative impact on the patient's quality of life.

METHODS

In the present review, we summarize the diagnostic criteria, prevalence, predisposing factors, the lesion site, the impact of PSD on the clinical evolution of the patient, the current therapeutic approaches and even the relationship between depression and cerebrovascular disease.

RESULTS

There are differences in relation to prevalence, essentially due to the use of different diagnostic criteria. Also, there have been few studies focusing on the search for factors that are predictive of PSD (age, female sex, single vascular lesion independent of site) and the reluctance to initiate preventive treatments to minimize the effects on the clinical evolution of the patients. There have been several advances with respect to the treatment of PSD. It seems that treatments show improvement trends, but today there is not enough evidence to recommend a preventive therapy for depression in any stroke patient.

CONCLUSIONS

We consider that the prevalence of PSD is relevant and that the risk factors as well as the early diagnosis are important for the best management and prognosis of stroke patients. Further studies are needed in this field in order to reduce PSD.

Association of AGTR1 with 18-month treatment outcome in late-life depression

OBJECTIVE

Converging lines of evidence implicate vascular factors in late-life depression, and argue that late-life depression is a distinct entity among the mood disorders. The A1166C polymorphism in the angiotensin II receptor, vascular type 1 (AGTR1) gene has been associated with a range of vascular diseases. This study investigated the association of AGTR1 genotype on 18-month treatment outcome in late-life depression.

METHODS

In a large, prospective cohort study, patients with late-life depression received individualized treatment using a standardized algorithm. The authors genotyped participants at the AGTR1 A1166C single nucleotide polymorphism (SNP) using standardized methodology, then used survival analysis to estimate the impact of A1166C and demographic variables on time to remission during 18 months of follow-up.

RESULTS

The hazard ratio for AGTR1 homozygous C/C status was 0.37. The A1166C SNP showed evidence for genotypic and allelic association in a comparison of remitted and unremitted/censored subjects.

CONCLUSION

Consistent with its association with numerous vascular disorders, AGTR1 is associated with treatment outcome in late-life depression. Further studies are needed to replicate this finding, and to investigate the impact of other genetic markers of vascular disease on late-life depression outcome.

[Validity of vascular depression as a specific diagnostic: a review]

INTRODUCTION

A number of authors have suggested that cerebrovascular disease may predispose, precipitate, or perpetuate some geriatric depressive syndromes. These "vascular depressions" may result from damage of striato-pallido-thalamo-cortical pathways which frequently occurs in cerebrovascular disease.

METHOD

We have searched the English and French literature published between 1996 (when the "vascular depression" hypothesis was first stated) and December 2004 through the Medline computer database and examined the validity of the concept of "vascular depression" thanks to four levels of validity: face validity, descriptive validity, construct validity and predictive validity. The face validity is the extent to which experts agree about the existence of a nosological entity.

RESULTS

The reviews published in this field broadly support the concept of "vascular depression" as a specific disorder. However many authors highlighted the fact that depression has been shown to precede vascular diseases and that depression and vascular diseases may both share some pathogenic or genetic determinants. These interactive and co-morbid relationships between depression and cerebrovascular diseases are difficult to disentangle. The descriptive validity refers to the degree of the clinical specificity of a disorder. It appears only moderate regarding the clinical studies carried out on this issue. However, a late-onset, the absence of a family history of mental illness, the lack of insight, lassitude, psychomotor retardation, a greater disability and particular neuropsychological dysfunctions may be associated with vascular depression. The construct validity, which refers to the degree to which the physiopathological processes involved in an illness are understood, appears difficult to establish because of the complex interactive relationships between cerebrovascular disease and depression. However, cerebrovascular diseases may contribute to the occurrence of depressive symptoms independently of its psychosocial burden. The predictive validity refers to the degree to which a syndrome is characterized by a specific response to treatment or a specific natural history. As regards response to treatment, vascular depression appears rather specific in the sense of a worse response to antidepressants and electroconvulsive therapy. The studies on the natural history of vascular depression lead to inconsistent results. According to some authors, this relative resistance to treatment may be explained by structural rather than functional, and thus potentially irreversible disruption in neural networks.

CONCLUSION

In conclusion, the systematic review of the validity of vascular depression broadly supports this concept. However, further studies are needed to decipher the relationships between depression and cerebrovascular disease. Finally, we suggest that it could be more relevant for future researches in this field if the diagnostic criteria for vascular depression were narrowed and required the presence of both neuro-imaging changes and cerebrovascular disease.

[Post-stroke depression: clinical aspects, epidemiology, therapy, and pathophysiology]

Post-stroke depression (PSD) is the most frequent psychiatric complication following ischemic stroke, affecting up to 50% of all such patients. Moreover, PSD is associated with increased morbidity and mortality following ischemic stroke. In clinical practice, PSD is underdiagnosed and many affected patients do not receive adequate treatment. This review article summarizes current knowledge regarding epidemiogy, clinical features, risk factors and predisposition, therapy, and prophylaxis of PSD.

White-matter integrity predicts stroop performance in patients with geriatric depression

BACKGROUND

This study tested the hypothesis that microstructural white matter abnormalities in frontostriatal-limbic tracts are associated with poor response inhibition on the Stroop task in depressed elders.

METHOD

Fifty-one elders with major depression participated in a 12-week escitalopram trial. Diffusion tensor imaging was used to determine fractional anisotropy (FA) in white matter regions. Executive function (response inhibition) was assessed with the Stroop task. Voxelwise correlational analysis was used to examine the relationship between Stroop performance and fractional anisotropy.

RESULTS

Significant associations between FA and Stroop color word interference were evident in multiple frontostriatal-limbic regions, including white matter lateral to the anterior and posterior cingulate cortex and white matter in prefrontal, insular, and parahippocampal regions.

CONCLUSIONS

These findings suggest that microstructural white matter abnormalities of frontostriatal-limbic networks are associated with executive dysfunction of late-life depression. This observation provides the rationale for examination of specific frontostriatal-limbic pathways in the pathophysiology of geriatric depression.

Neuroimaging in late-life depression

Late-life depression may be associated with vasculopathy. Neuroimaging has been a critical tool in exploring the relationship between this form of depression and vascular factors. Magnetic resonance imaging has been the most widely used tool, but there is potential to use other structural imaging techniques as well as functional neuroimaging methodologies. Neuroimaging may potentially be utilized at some point as a biomarker for late-life depression, thus helping with diagnosis and guiding treatment.

White matter hyperintensities rather than lacunar infarcts are associated with depressive symptoms in older people: the LADIS study

OBJECTIVE

Both white matter hyperintensities (WMH) and lacunar infarcts have been associated with the development of depression in older subjects, although the relative importance of the two and the influence of lesion location and concomitant vascular disease are unclear. This study investigates the relationship between location and burden of WMH and lacunes on depressive features in older people.

METHOD

In a pan-European multicenter study of 626 older subjects, the authors examined the relationship between regional magnetic resonance imaging white matter hyperintensities, number of lacunar infarcts, depressive symptoms as assessed by the 15-item geriatric depression scale (GDS), cognitive status (Mini-Mental Status Examination), hypertension, and self-perceived health quality of life (QoL).

RESULTS

The authors found depressive symptoms to be correlated with WMH rating in the frontal (N=626; Spearman's rho=0.161, p <0.001) and temporal (rho=0.14, p <0.001) but not occipitoparietal region (rho=0.07, p=0.07). Basal ganglia lacunes were only weakly correlated with GDS (rho=0.09, p=0.03), and lacunes in other regions showed no association. In a ordinal logistic regression model (controlling for QoL, Mini-Mental Status Examination, age, and with an interaction between WMH and hypertension), temporal WMH in the absence of hypertension independently predicted GDS, whereas neither history of stroke nor number of lacunar infarcts did. The authors compared left- versus right-sided WMH and found no effect of laterality on depressive symptoms.

CONCLUSIONS

The results suggest that in this population of nondisabled older people, WMH have a greater influence on depressive symptoms than infarcts.

Cerebrovascular disease basis of depression: post-stroke depression and vascular depression

The close association between cerebrovascular disease and depression has been known for more than a century, yet much of the progress in understanding the cerebrovascular basis of depression in late life has been spurred by development of two concepts: 'post-stroke depression' and 'vascular depression'. The purpose of this review is to examine the epidemiology, diagnostic features, course, pathophysiology and prognosis of post-stroke depression and vascular depression, to highlight their common features, and to contrast the distinct aspects of these two subtypes of geriatric depression.

Neuroimaging in psychiatry: An update

The introduction of neuroimaging techniques in the 1960s has revolutionized the study of the biology of psychiatric disorders with implications for psychiatric practice. These comprise structural (computerized axial tomography, magnetic resonance imaging) and functional (including neurochemical/neuropharmacological techniques such as single-photon emission computerized tomography, positron emission tomography, functional magnetic resonance imaging, and magnetic resonance spectroscopy) techniques. As a result, we now have a better understanding of the morbid anatomy, pathophysiology, and chemical pathology of organic brain disease, schizophrenia, addictions, and affective disorders. This selective review will focus on recent advances in the use and application of neuroimaging techniques in the study of addictions, schizophrenia, and depression. Reference will be made to studies conducted in the United Arab Emirates on Arab patients with depression, schizophrenia, and alcohol dependence. The refinement of these techniques and their application in the study of psychiatric disorders will redefine these disorders, promising their deconstruction and the development of novel and more specific treatments.

Lobar distribution of lesion volumes in late-life depression: the Biomedical Informatics Research Network (BIRN)

White matter hyperintense lesions on T2-weighted images are associated with late-life depression. Little work has been carried out examining differences in lesion location between elderly individuals with and without depression. In contrast to previous studies examining total brain white matter lesion volume, this study examined lobar differences in white matter lesion volumes derived from brain magnetic resonance imaging. This study examined 49 subjects with a DSM-IV diagnosis of major depression and 50 comparison subjects without depression. All participants were age 60 years or older. White matter lesion volumes were measured in each hemisphere using a semiautomated segmentation process and localized to lobar regions using a lobar atlas created for this sample using the imaging tools provided by the Biomedical Informatics Research Network (BIRN). The lobar lesion volumes were compared against depression status. After controlling for age and hypertension, subjects with depression exhibited significantly greater total white matter lesion volume in both hemispheres and in both frontal lobes than did control subjects. Although a similar trend was observed in the parietal lobes, the difference did not reach a level of statistical significance. Models of the temporal and occipital lobes were not statistically significant. Older individuals with depression have greater white matter disease than healthy controls, predominantly in the frontal lobes. These changes are thought to disrupt neural circuits involved in mood regulation, thus increasing the risk of developing depression.

Frontal signal hyperintensities in mania in old age

OBJECTIVE

Signal hyperintensities (SH) on magnetic resonance (MR) imaging have been associated with increased age and with mood disorders. Frontal and subcortical neuropathology has been implicated in the pathophysiology of mania and bipolar disorders. The authors assessed frontal and subcortical SH in elderly bipolar manic patients and the comparison group, and hypothesized that SH scores would be greater in the patient group.

METHOD

MR imaging was performed in patients aged > or = 60 years with bipolar disorder, mania, and in a same-aged community comparison group. SH were rated blindly using the Boyko system. Frontal deep white matter and basal ganglia SH were assessed in the left and right hemispheres.

RESULTS

SH scores were significantly greater in patients (N = 40) than the comparison group (N = 15) in frontal deep white matter (left: p = 0.003; right: p = 0.023) based on Mann-Whitney two-sample exact tests. The SH scores in the subcortical gray regions overlapped in these groups. In patients, higher right frontal SH scores were associated with later age at onset of mania.

CONCLUSIONS

Frontal deep white matter SH may be increased in elders with bipolar disorder. Further study of the relationship of SH to age at onset in elders is warranted.

Depression in the older adult

Older adults who visit the primary care physician's office often exhibit depressive symptoms. The challenge for the physician and other office staff is to determine what these symptoms mean: Loneliness? Fear? Grief? A consequence of a coexisting medical condition? A DSM depressive disorder? Or something else? Addressing ambiguous symptoms that may represent a depressive disorder may be difficult in the busy office setting. The findings of one recent study suggest that it is not lack of knowledge that impedes the recognition of depression but rather the conditions under which clinical decision making occurs. The process of ruling out medical diagnoses and opening the door to consider a mental health diagnosis can be time-consuming and circuitous, especially if the clinician is not already familiar with the patient or if the clinician who is familiar with the patient perceives insufficient time to deal with the issues raised by opening the door. The fundamental challenge for the primary care clinician as aging baby boomers inundate the health care system is to restructure office practice to recognize, assess, and manage geriatric syndromes including depression. The underlying principle for successful restructuring is acknowledging that these syndromes have multiple causes requiring multifaceted interventions. Operationally, doing simple things consistently and well may have significant impact. By consistently recognizing biologic and psychosocial risk factors for depression, by taking a careful history (including the two-question screen), and by conducting a thorough physical examination, the office-based clinician will generally have a strong clinical hunch about the presence or absence of a depressive disorder and any comorbid medical and neuropsychiatric conditions. Armed with this information, additional laboratory and brain imaging studies and subsequent management strategies are straightforward.

Psychiatric disease in the genomic era: rational approach

Although the introduction of explicit diagnostic criteria and rule-based classifications, such as Research Diagnostic Criteria, Diagnostic and Statistical Manual Ed 3 and Ed 4, has dramatically influenced teaching and research psychiatric practice, it has significant limitations. As new knowledge is developed with genetic, imaging and metabolomic technologies, a method to incorporate this research in a systematic manner with current classification systems is needed. The current approach, which is essentially nominalist in character, has to be developed where new data and new concepts of disease can be integrated and tested. Examples of how this could happen is shown in the context of Alzheimer's disease and subcortical ischemic disease. It is likely that a standardized approach that can develop and modify classification systems in a timely manner, based on science and free of societal and political influence, can enhance research, teaching and clinical practice.

Prefrontal and striatal activation during sequence learning in geriatric depression

BACKGROUND

Frontostriatal dysfunction is a primary hypothesis for the neurocognitive changes of depression in late life. The aim of the present study was to test this hypothesis with the use of functional magnetic resonance imaging (fMRI) tasks that are known to engage the prefrontal and neostriatal cognitive circuits.

METHODS

Twenty-three elderly subjects (mean age, 69.9 years) participated: 11 subjects with a current major depressive episode and 12 nondepressed elderly control subjects. Subjects underwent fMRI while performing a concurrent implicit and explicit sequence learning task. Region of interest (ROI)-based analyses were conducted, focusing on the dorsal anterior cingulate cortex, the dorsolateral prefrontal cortex, and the neostriatum.

RESULTS

As expected, both the control and depressed subjects learned the sequence during both implicit and explicit conditions. During explicit learning, decreased prefrontal activation was found in the depressed subjects, along with increased striatal activation. The increased striatal activity in the depressed subjects was due to increased activity on the trials that violated the sequence. During implicit learning, no significant differences were found between the groups in the identified ROIs.

CONCLUSIONS

The increased striatal activation on trials that violated the sequence demonstrates a greater response to negative feedback for depressed compared with control subjects. Our observations of significant differences in both prefrontal and striatal regions in the depressed elderly subjects relative to elderly control subjects supports the frontostriatal dysfunction hypothesis of late-life depression.

Hypofrontality and microvascular dysregulation in remitted late-onset depression assessed by functional near-infrared spectroscopy

Accumulated evidence suggests the involvement of vascular factors in late-onset depression. Late-onset depression has characteristics of poor outcome, cognitive decline, and high prevalence rather than early-onset depression. The aim of the present study was to determine whether or not the functional hypofrontality--that is, hypoperfusion and hypometabolism in the frontal lobes-seen in late-onset depression is a trait-dependent abnormality of microvascular regulation. This study was conducted on 10 patients with remitted late-onset major depressive disorder (MDD) and 10 healthy volunteers matched for vascular factors and subcortical, or white matter, hyperintensities (WMH). Using near-infrared spectroscopy combined with magnetic resonance imaging, we investigated the microvascular reactivity in the prefrontal cortex during a cognitive task and during carbon dioxide (CO(2)) inhalation. Activation of the prefrontal cortex during the cognitive task was significantly less in patients as compared with controls, although task performance was not significantly different between the two groups. In the patients, a tendency of negative correlation between the reduced prefrontal activation during a cognitive task and the severity of hyperintensity in periventricular region was observed. Vasomotor reactivity to CO(2) inhalation was significantly lower in the patients than in the controls. Although there was no significant association between the activation during the cognitive and that during the CO(2) inhalation task, the present results suggest that prefrontal microvascular dysregulation as shown by NIRS is involved in the pathophysiological basis of functional hypofrontality in late-onset depression. This finding will provide a new framework for the development of diagnostic methods, treatments, and preventive strategies against late-onset depression.

Greater MRI lesion volumes in elderly depressed subjects than in control subjects

Hyperintense lesions in both white matter and gray matter on T2-weighted magnetic resonance imaging (MRI) are associated with late-life depression. This large study examined differences in gray and white matter lesion volumes on brain MRI between 253 elderly depressed and 146 control subjects. White matter and gray matter lesion volumes were measured in each hemisphere using a semi-automated segmentation process and compared against depression status. Depressed subjects exhibited significantly greater total white matter (mean 7.22 ml) and gray matter (mean 0.30 ml) lesion volumes in both hemispheres than did control subjects (mean 4.87 ml in white matter and 0.18 ml in gray matter). This difference remained statistically significant even after controlling for confounders such as age, sex, race and reports of hypertension, diabetes and heart disease. Patients with late-life depression have larger white matter lesion and gray matter lesion volumes than do control subjects. Future research should combine similar volumetric techniques with methods of identifying the location of lesions specific to late-life depression.

White matter hyperintensities and chronicity of depression

OBJECTIVE

White matter hyperintensities (WMHs) on T(2)-weighted magnetic resonance imaging (MRI) of the brain are associated with advanced age and late-life depression. Most investigations predominantly found these lesions in frontal lobe and basal ganglia supporting the hypothesis of a fronto-striatal dysfunction in depression. A prospective study was undertaken to investigate the association between extent of WMHs and clinical outcome in elderly depressed patients.

METHODS

Thirty-one non-demented depressed subjects underwent a 1.5 T cranial MRI scan. The MRI scans were analysed in consensus by two experienced radiologists. Each MRI scan was assessed for presence and extent of WMHs, which are differentiated in periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs). A total of 21 patients of the original cohort of 31 patients were re-assessed 5 years after baseline assessment. We ascertained the severity of depressive symptoms, the longitudinal course of depression, the cognitive decline and the global assessment of functioning at follow-up visit.

RESULTS

(1) Subjects with greater extent of WMHs had a significant higher Hamilton Depression Rating Scale (HAM-D) score, (2) had more severe longitudinal courses of depression (3) and had a lower Mini-Mental State Examination (MMSE) score.

CONCLUSIONS

WMHs on MRI are associated with poorer outcome in elderly depressed subjects. Further studies are needed to evaluate WHMs as prognostic factor for an appropriate treatment decision-making.

Cognitive function over the treatment course of depression in middle-aged patients: correlation with brain MRI signal hyperintensities

INTRODUCTION

It has been proposed that the often found hyperintensities on MRI representing vascular changes might be correlated with a worse outcome of cognitive malfunction in depression. The purpose of this study was to evaluate neuropsychological status in the acute depressed state and following remission and to investigate the potential relationship between MRI hyperintensities and neuropsychological functioning through the treatment course in a group of middle-aged depressed patients.

MATERIALS AND METHODS

Twenty-seven depressed patients were assessed by a series of neuropsychological tests at the beginning of the depressive episode and again after an euthymic phase of 6 months following treatment. Thirty healthy controls were tested at comparable intervals. In all patients and controls a MRI was performed to identify hyperintensities representing a possible correlation with test performance during treatment course.

RESULTS

At the onset of a depressive episode patients performed significantly worse than the controls in all tests. After sustained remission the patient group still performed significantly worse in verbal memory and verbal fluency compared to controls. There were no significant correlations between number of presence of vascular risk factors, or presence of hyperintensities on MRI, and cognitive abilities at either time point.

DISCUSSION

These findings favor the hypothesis that some neuropsychological deficits might persist following treatment for depression, even in middle-aged patients. We found, however, that any residual cognitive deficit is not associated with MRI-hyperintensities in this age-group.

Cerebrovascular disease and late-life depression

Depression may occur as a result of vascular disease in a significant subpopulation of elderly persons. Indirect support for vascular disease as an underlying etiology of late-life depression includes the high rate of depression in patients with vascular disease, the frequency of "silent stroke" and white-matter hyperintensities in late-life depression, and the lower frequency of positive family histories of depression in such patients. The authors evaluate the associations of late-life depression with cerebrovascular disease by reviewing the existing pathophysiological, prognosis, and treatment-outcomes studies. Findings are based on review of the current literature systematically searched in electronic databases. Review of such studies indicates a high frequency of depression in older patients with cardiovascular and cerebrovascular diseases, and the possibility of a bidirectional relationship between depression and vascular disease. Studies examining patients with vascular depression have found that such patients have different symptom profiles, greater disability, and higher risk for poorer outcomes than those with nonvascular depression. Since the vascular depression hypothesis was proposed as a conceptual framework, evidence has accumulated that patients with vascular depression may have poorer outcomes that may be related in part to executive dysfunction and consequent disability. However, the association of vascular risk factors with geriatric depression has not been consistent in the studies to-date. Although an association between a subset of late-life depression and vascular disease is clear, significant gaps remain in our understanding. Further research is needed to establish the precise linkages and interactions between vascular disease and geriatric depression.

Is vascular depression a distinct sub-type of depressive disorder? A review of causal evidence

BACKGROUND

Vascular depression is an important conceptual and clinical concept.

OBJECTIVE

To apply criteria which, in an ideal world, should be satisfied before an association between depression and vascular disease can be considered robust.

METHOD

A literature review with discussion of findings in the light of recently suggested guidelines for the development of new psychiatric disorders.

RESULTS

There is considerable evidence linking depression in later life with vascular brain disease but the interaction is bi-directional. Depression and vascular disease could be mediated by factors other than traditional vascular risk factors. There is increasing interest in mechanisms such as inflammatory processes which may mediate both depression and vascular disease.

CONCLUSIONS

Vascular depression provides a useful framework with which to remind the clinician of important interactions between depression and vascular disease but conceptually it may be too restrictive.

Is poststroke depression a vascular depression?

As we learn more about the relationships between depression and cerebrovascular disease (CVD), a complex picture is emerging in which the chain of causality seems to spiral on itself: progressive or focal brain damage, cognitive impairment, depressive symptoms, dementia, and cardiovascular diseases, all seem to be liable to lead to one or another. Stroke may lead to depression, and the inverse may also be true. Depression may lead to cognitive impairment and cardiovascular diseases, which in turn may lead to subtle brain impairment, thereby causing more depression and cognitive impairments, and so on. In this presentation, we provide a rapid glance at the complexities of such issues.

Is major depression a neurologic disorder with psychiatric symptoms?

In the last decade, multiple investigator groups have identified structural changes of various neuroanatomic structures in patients with idiopathic major depression and bipolar disorders. Using high-resolution MRI of the brain and functional neuroimaging studies (i.e., PET, SPECT), researchers have described decreases in the volume of hippocampal formation, amygdala, entorhinal cortex, various frontal lobe structures, and basal ganglia, in addition to abnormal cerebral blood flow and metabolic activity in these structures as well as in thalamic nuclei. Similar structural and functional changes have been identified in patients with depression associated with a variety of neurologic disorders (i.e., stroke, Parkinson's disease, epilepsy, Alzheimer's dementia). In addition, recent data have shown that depression is a risk factor for the development of several neurologic disorders, including epilepsy, stroke, and Parkinson's disease and bears a negative impact on the course and outcome of most neurologic disorders. This article reviews these data and provides evidence that major depressive and bipolar disorders may in fact be neurologic disorders with psychiatric symptoms.

Clinical characteristics of magnetic resonance imaging-defined subcortical ischemic depression

BACKGROUND

There is a substantial body of research supporting the vascular depression hypothesis of late-life depression. To update this hypothesis so it incorporates recent research, we propose that the term subcortical ischemic vascular depression may be a more accurate representation of the disease process. We sought to investigate this diagnosis as a construct by examining differences between depressed subjects with and without magnetic resonance imaging defined subcortical ischemic vascular depression.

METHODS

This case-control study examined 139 depressed elderly subjects. Demographic data, psychiatric, medical, and family history, depressive symptomatology, and functional impairment were compared between groups dichotomized based on neuroimaging findings.

RESULTS

Seventy-five (54%) of the subjects met neuroimaging criteria for subcortical ischemic vascular depression. Age was most strongly associated with increased prevalence of subcortical ischemic vascular depression. Lassitude and a history of hypertension were also positively associated with the diagnosis; a family history of mental illness and loss of libido were negatively associated with the diagnosis.

CONCLUSIONS

These data support that subcortical ischemic vascular depression may be a specific syndrome from other types of late-life depression. Further research is needed to further characterize this disorder, particularly in regards to cognitive function and treatment implications.

The Danish PET/depression project: performance on Stroop's test linked to white matter lesions in the brain

The Stroop test (ST) assesses the integrity of prefrontal and cingulate functioning. Patients with major depression perform poorly on the ST, pointing to disturbed function in these areas. We therefore used positron emission tomography to study 41 in-patients with major depression and 46 age- and gender-matched controls during neuropsychological activation with the ST. Magnetic resonance imaging was used for coregistration and for description of the localization of white matter lesions (WML). The cerebral blood flow (CBF) changes during ST were mapped for each of the two study groups, and inter-group differences were calculated on a voxel-by-voxel basis. The patients were followed for 3 to 5 years to ensure diagnostic stability. The control group activated anterior cingulate regions, prefrontal cortices, insula, thalamus and cerebellum. Despite the patients' slower performance with more errors, no significant differences were found comparing the activations in the two groups. The performance was, however, correlated to the number of WML in frontal lobes, insula and adjacent to the basal ganglia, whereas WML in other locations was not related to performance. We thus partly explain the poorer performance by increased frequency of WML in frontostriatal pathways in the depressed patients, impairing neurotransmission.

Structural MRI changes of the brain in depression

For many years, investigators have been trying to identify the neuroanatomical structures responsible for the development of neuropsychiatric disorders, specifically depression and schizophreniform disorders. The available data were based on observations made in neurological patients who developed a psychiatric comorbid disorder following the neurologic insult. With the advances in high-resolution magnetic resonance imaging and functional neuroimaging studies, we have witnessed in the last decade a wealth of new data that identify structural neuroimaging changes in mesial temporal structures, prefrontal cortex and basal ganglia in major depressive disorders. The purpose of this article is to briefly review the published data on neuroanatomical structural changes associated with major depressive and bipolar disorders.

The association of psychosocial factors and depression with hypertension among older adults

OBJECTIVE

To examine the relationship between depression and hypertension in an elderly population and how psychosocial variables influence this relationship.

METHODS

The study included 293 subjects, who met DSM-IV criteria for unipolar depression, and 151 subjects with no psychiatric disorder. All subjects were over the age of 58. Participants were administered the Duke Depression Evaluation Schedule at baseline and at yearly intervals for 3 years.

RESULTS

Cross-sectional analyses of baseline data showed that hypertensive patients were more likely to be depressed and of non-white race. Bivariate analyses provided evidence that hypertension was associated with higher amounts of total stressors and lower social support. No differences in the prevalence of hypertension were found between men and women. In addition, there was no evidence of change in hypertension status over time.

CONCLUSION

Patients, especially minorities, who experience depression, stress, or a lack of social support, are at an increased likelihood of having hypertension and clinicians should consider this risk when treating this population.

Comparison of prefrontal cell pathology between depression and alcohol dependence

Chronic alcohol abuse is often co-morbid with depression symptoms and in many cases it appears to induce major depressive disorder. Structural and functional neuroimaging has provided evidence supporting some degree of neuropathological convergence of alcoholism and mood disorders. In order to understand the cellular neuropathology of alcohol dependence and mood disorders, postmortem morphometric studies have tested the possibility of alterations in the number and size of cells in the prefrontal cortex and other brain regions. The present review compares the cell pathology in the prefrontal cortex between alcohol dependence and depression, and reveals both similarities and differences. One of the most striking similarities is that, although pathology affects both neuronal and glial cells, effects on glia are more dramatic than on neurons in both alcohol dependence comorbid with depression and idiopathic depression. Moreover, prefrontal cortical regions are commonly affected in both depression and alcoholism. However, the cellular changes are more prominent and spread across cortical layers in alcohol dependent subjects than in subjects with mood disorders, and changes in glial nucleus size are opposite in alcoholism and depression. It could be argued that one defining factor in the manifestation of the depressive pathology is a reduction in the glial distribution in the dlPFC that is reflected in a reduced glial density. In alcoholism reduced glial nuclear size might be related to the cytotoxic effects of prolonged alcohol exposure, while in MDD, in the absence of alcohol abuse, other processes might be responsible for the increase in average size of glial nuclei. In either case abnormal function related to glial reduction would be associated with depression due to insufficient glial support to the surrounding neurons.