Structural neuroimaging of geriatric depression

Neuroimaging features of depression-frailty phenotype in older adults: a pilot study

OBJECTIVE

Frailty and late-life depression (LLD) often coexist and share several structural brain changes. We aimed to study the joint effect LLD and frailty have on brain structure.

DESIGN

Cross-sectional study.

SETTING

Academic Health Center.

PARTICIPANTS

Thirty-one participants (14 LLD+Frail and 17 Never-depressed+Robust).

MEASUREMENT

LLD was diagnosed by a geriatric psychiatrist according to the Diagnostic and Statistical Manual of Mental Disorders 5th edition for single episode or recurrent major depressive disorder without psychotic features. Frailty was assessed using the FRAIL scale (0-5), classifying subjects as robust (0), prefrail (1-2), and frail (3-5). Participants underwent T1-weighted magnetic resonance imaging in which covariance analysis of subcortical volumes and vertex-wise analysis of cortical thickness values were performed to access changes in grey matter. Participants also underwent diffusion tensor imaging in which tract-based spatial statistics was used with voxel-wise statistical analysis on fractional anisotropy and mean diffusion values to assess changes in white matter (WM).

RESULTS

We found a significant difference in mean diffusion values (48,225 voxels; peak voxel: pFWER=0.005, MINI coord. (X,Y,Z) = -26,-11,27) between the LLD-Frail group and comparison group. The corresponding effect size (f=0.808) was large.

CONCLUSION

We showed the LLD+Frailty group is associated with significant microstructural changes within WM tracts compared to Never-depressed+Robust individuals. Our findings indicate the possibility of a heightened neuroinflammatory burden as a potential mechanism underlying the co-occurrence of both conditions and the possibility of a depression-frailty phenotype in older adults.

A longitudinal study of the association between basal ganglia volumes and psychomotor symptoms in subjects with late life depression undergoing ECT

Psychomotor dysfunction (PMD) is a core element and key contributor to disability in late life depression (LLD), which responds well to electroconvulsive therapy (ECT). The neurobiology of PMD and its response to ECT are not well understood. We hypothesized that PMD in LLD is associated with lower striatal volume, and that striatal volume increase following ECT explains PMD improvement. We analyzed data from a two-center prospective cohort study of 110 LLD subjects (>55 years) receiving ECT. Brain MRI and assessment of mood, cognition, and PMD was performed 1 week before, 1 week after, and 6 months after ECT. Volumetry of the caudate nucleus, putamen, globus pallidus, and nucleus accumbens was derived from automatically segmented brain MRIs using Freesurfer®. Linear multiple regression analyses were used to study associations between basal ganglia volume and PMD. Brain MRI was available for 66 patients 1 week post ECT and in 22 patients also six months post ECT. Baseline PMD was associated with a smaller left caudate nucleus. One week after ECT, PMD improved and volume increases were detected bilaterally in the caudate nucleus and putamen, and in the right nucleus accumbens. Improved PMD after ECT did not relate to the significant volume increases in these structures, but was predicted by a nonsignificant volume change in the right globus pallidus. No volume differences were detected 6 months after ECT, compared to baseline. Although PMD is related to lower striatal volume in LLD, ECT-induced increase of striatal volume does not explain PMD improvement.

Intensity and type of physical activity predicts depression in older adults

This study examined whether various levels of physical activity among older adults predicted levels of depression and whether there were racial differences in the levels and types of physical activities engaged in by adults aged 50 and older.

METHOD

Data from the 2015-2016 National Health and Nutrition Examination Survey (NHANES) were analyzed for 2,474 adults aged 50 years and older. Variables of focus were demographics, physical activity and depression, assessed using the Physical Activity Questionnaire and the Mental Health - Depression Screener.

RESULTS

There was a significant positive relationship between income and depression; individuals with higher income had lower levels of depression. Simple linear regression revealed income significantly predicted depression scores, b = -.20, F(1, 2296) = 96.35, p < .001, explaining 4% of the variance, R2 = .04. As age increased, all levels of physical activity declined, regardless of the category. Vigorous recreation-related activity and moderate recreation-related activity each made significant, unique contributions to depression scores.

CONCLUSION

Findings from the current study suggest that physical activity interventions should be culturally appropriate and tailored to the needs and abilities of individual older adults to maximize benefits and minimize adverse events, particularly among community dwelling older adults.

Transcranial sonography imaging of brainstem raphe, substantia nigra and cerebral ventricles in patients with geriatric depression

OBJECTIVES

Geriatric depression is a special condition associated with a chronic course, treatment resistance and vascular processes. However, its neurobiology has not been fully elucidated. There is no study in geriatric depression evaluating deep brain structures with transcranial sonography (TCS) which is a low-cost, non-invasive and practical tool. The present study aimed to evaluate the changes in the echogenicity of brainstem raphe (BR), substantia nigra (SN) and ventricular diameters by TCS in association with cognitive dysfunctions in patients with geriatric depression.

METHODS

Echogenicity of BR and SN were assessed and transverse diameters of the third ventricle and frontal horns of the lateral ventricles were measured by TCS in 34 patients with DSM-5 major depression and 31 healthy volunteers aged 60 and older. Cognitive functions were evaluated by using Mini Mental State Examination, Montreal Cognitive Assessment Tool, Clock Drawing Test and Subjective Memory Complaints Questionnaire.

RESULTS

Although depressed patients had more subjective memory complaints than controls, they had similar cognitive performances. Reduced echogenicity (interrupted/invisible echogenic line) of BR was found to be significantly higher and the ventricular diameters were larger in the depressed group. There was no difference between the groups in terms of SN echogenicity. There was no correlation between ventricular diameters and depression severity or cognitive functions.

CONCLUSIONS

Results of the present study are important in terms of pointing out neurobiological changes related to geriatric depression which are in parallel with the results of the studies in younger patients with depression. However, long-term follow-up studies are required for accurate differentiation of neurocognitive disorders.

Cortical thickness increases with levomilnacipran treatment in a pilot randomised double-blind placebo-controlled trial in late-life depression

BACKGROUND

Late-life depression (LLD) is associated with significant medical comorbidity, cognitive impairment, and suboptimal treatment response compared to depression experienced earlier in life. Levomilnacipran (LVM) is a novel antidepressant the effects of which on neuroplasticity have not yet been investigated. We investigated the effect of LVM on cortical thickness in a pilot randomised placebo-controlled trial in LLD.

METHODS

Twenty-nine adults (≥ 60 years) with major depression (48.3% female; mean age = 71.5 ± 5.8 years; mean education = 16.0 ± 1.7 years) were randomised to either LVM or placebo for 12 weeks. T1-weighted images were acquired at baseline and 12 weeks. Thirteen subjects (six LVM and seven placebo) completed the study. Group differences in cortical thickness change across the study period were evaluated, with age and total intracranial volume included as covariates.

RESULTS

Dropout rates did not differ significantly between groups. The LVM group had significantly more side effects, but no serious adverse events were reported. Lower LVM dose (≤ 40 mg) was better tolerated than higher doses (80-120 mg). Additionally, the LVM group showed a larger increase in cortical thickness in the right postcentral gyrus (primary somatosensory), supramarginal gyrus (sensory association region), and lateral occipital cortex (visual cortex) compared to the placebo group and greater reductions in the left insula.

CONCLUSIONS

LVM may be less tolerable by older adults with depression and the effects on cortical thickness across sensory and sensory association regions may be related to the experience of side effects. Larger studies are necessary to evaluate treatment efficacy, tolerability, and neural effects of LVM in LLD.

Cognitive behavioural therapy for the treatment of late life depression: study protocol of a multicentre, randomized, observer-blinded, controlled trial (CBTlate)

BACKGROUND

Late-life depression (LLD) is one of the most prevalent mental disorders in old age. It is associated with various adverse outcomes and frequent use of health care services thereby remaining a serious public health concern. Compared with depression in early adulthood, most treatment options of LLD are less effective. Psychotherapy may be particularly beneficial for LLD due to specific psychological conditions in old age and a low risk of side effects. Although cognitive behavioural therapy (CBT) is highly established and effective in depression in young and mid-life there is only a limited number of small studies on CBT in LLD. An LLD-specific CBT has not yet been compared to an active, but unspecific supportive psychological intervention in a multicentre trial.

METHODS

Here we present the design of the CBTlate trial, which is a multicentre, randomized, observer-blinded, active-controlled, parallel group trial. CBTlate aims at including 248 patients with LLD of both genders at 7 sites in Germany. The purpose of the study is to test the hypothesis that a 15-session individually-delivered CBT specific for LLD is of superior efficacy in reducing symptoms of depression in comparison with a supportive unspecific intervention (SUI) of the same quantity. The intervention includes 8 weeks of individual treatment sessions twice per week and a follow-up period of 6 months after randomization. The primary end point is the severity of depression at the end of treatment measured by the self-rated 30-item Geriatric Depression Scale (GDS). Secondary endpoints include depressive symptoms at week 5 and at follow-up (6 months after randomization). Additional secondary endpoints include the change of depressive symptoms assessed with a clinician-rating-scale and a patient reported outcome instrument for major depressive disorder, anxiety symptoms, sleep, cognition, quality of life, and overall health status from baseline to end-of treatment and to end of follow-up. Add-on protocols include MRI and the collection of blood samples.

DISCUSSION

This study is the first multicentre trial of a specific CBT intervention for LLD compared to an unspecific supportive psychological intervention administered in a specialist setting. It has important implications for developing and implementing efficient psychotherapeutic strategies for LLD and may be a significant step to broaden treatment options for people suffering from LLD.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03735576, registered on 24 October 2018); DRKS (DRKS00013769, registered on 28 June 2018).

Longitudinal microstructural changes of cerebral white matter and their association with mobility performance in older persons

Mobility impairment in older persons is associated with brain white matter hyperintensities (WMH), a common finding in magnetic resonance images and one established imaging biomarker of small vessel disease. The contribution of possible microstructural abnormalities within normal-appearing white matter (NAWM) to mobility, however, remains unclear. We used diffusion tensor imaging (DTI) measures, i.e. fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), to assess microstructural changes within supratentorial NAWM and WMH sub-compartments, and to investigate their association with changes in mobility performance, i.e. Tinetti assessment and the 2.5-meters walk time test. We analyzed baseline (N = 86, age ≥75 years) and 4-year (N = 41) follow-up data. Results from cross-sectional analysis on baseline data showed significant correlation between WMH volume and NAWM-FA (r = -0.33, p = 0.002), NAWM-AD (r = 0.32, p = 0.003) and NAWM-RD (r = 0.39, p = 0.0002). Our longitudinal analysis showed that after 4-years, FA and AD decreased and RD increased within NAWM. In regional tract-based analysis decrease in NAWM-FA and increase in NAWM-RD within the genu of the corpus callosum correlated with slower walk time independent of age, gender and WMH burden. In conclusion, global DTI indices of microstructural integrity indicate that significant changes occur in the supratentorial NAWM over four years. The observed changes likely reflect white matter deterioration resulting from aging as well as accrual of cerebrovascular injury associated with small vessel disease. The observed association between mobility scores and regional measures of NAWM microstructural integrity within the corpus callosum suggests that subtle changes within this structure may contribute to mobility impairment.

Brain atrophy is a frequent finding in elderly patients with first episode psychosis

BACKGROUND

To characterize the yearly incidence, diagnostic distribution, and neuro-radiologic findings in patients aged over 60 years, referred to psychiatric treatment with first episode psychosis (FEP).

METHODS

A computerized search, including all patients referred to psychiatric treatment during 12 consecutive months with a de novo diagnosis of psychosis was performed in the Helsinki region catchment area with 1.2 million inhabitants. Diagnoses based on hospital records were made by a group of one neurologist and three psychiatrists. MRI- or CT scans performed as a part of routine clinical management were used when available.

RESULTS

107 patients (27 males and 80 females) with FEP were identified and categorized into four diagnostic groups: schizophrenia, delusional disorder, psychotic depression, and psychosis due to another medical condition. No patients with de novo onset mania were found. Psychosis due to another medical condition was the most common diagnosis. A high frequency of signs of cortical brain atrophy was seen in all diagnostic groups, while central atrophy was more frequent in patients with psychosis due to another medical condition than in the other groups.

CONCLUSION

Organic brain changes related to ageing or degenerative illnesses may be an etiologic factor in elderly patients with FEP.

Is 18F-FDG-PET suitable to predict clinical response to the treatment of geriatric depression? A systematic review of PET studies

BACKGROUND

Geriatric depression is one of the most common psychiatric disorders in later life. It differs from earlier depression in its presentation, etiology, risk factors, protective factors and outcome. Positron emission tomography (PET) can be used to detect changes in neural circuitry in neuropsychiatric disorders, and several authors have assessed its role in the diagnosis and follow-up of patients with geriatric depression. We reviewed the current evidence on the use of fluorine-18-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG-PET) in geriatric depressed patients to find predictors of treatment response.

METHODS

We searched PubMed/MEDLINE, Scopus, Embase, Cochrane Library, CINAHL and the PsycINFO databases to find relevant peer-reviewed articles on PET in geriatric depression using the search terms ('PET' or 'positron emission tomography') and ('mood' or 'affective disorder' or 'affective disorders' or 'depression' or 'dysthymia' or 'seasonal affective disorder').

RESULTS

Eleven articles comprising 128 patients were included. We extracted data on glucose uptake of depressed patients and controls at baseline and after different types of intervention (total sleep deprivation followed by a recovery sleep and treatment with selective serotonin reuptake inhibitors).

CONCLUSIONS

¹⁸F-FDG-PET showed significant alterations of glucose uptake in several brain areas, in particular the anterior cingulate cortex, which showed reduced metabolism after treatment, and was a predictor of treatment response.

Applications of magnetic resonance imaging for treatment-resistant late-life depression

Late-life depression (LLD) is a growing public and global health concern with diverse clinical manifestations and etiology. This literature review summarizes neuroimaging findings associated with depression in older adults and treatment-response variability. LLD has been associated with cerebral atrophy, diminished myelin integrity, and cerebral lesions in frontostriatal-limbic regions. These associations help explain the depression-executive dysfunction syndrome observed in LLD, and support cerebrovascular burden as a pathogenic mechanism. Furthermore, this review suggests that neuroimaging determinants of treatment resistance also reflect cerebrovascular burden. Of the theoretical etiologies of LLD, cerebrovascular burden may mediate treatment resistance. This review proposes that neuroimaging has the potential for clinical translation. Controlled trials may identify neuroimaging biomarkers that may inform treatment by identifying depressed adults likely to remit with pharmacotherapy, identifying individualized therapeutic dose, and facilitating earlier treatment response measures. Neuroimaging also has the potential to similarly inform treatment response variability from treatment with aripiprazole (dopamine modulator) and buprenorphine (opiate modulator).

Grey matter volume increase following electroconvulsive therapy in patients with late life depression: a longitudinal MRI study

BACKGROUND

The evidence on the mechanisms of action of electroconvulsive therapy (ECT) has grown over the past decades. Recent studies show an ECT-related increase in hippocampal, amygdala and subgenual cortex volume. We examined grey matter volume changes following ECT using voxel-based morphometry (VBM) whole brain analysis in patients with severe late life depression (LLD).

METHODS

Elderly patients with unipolar depression were treated twice weekly with right unilateral ECT until remission on the Montgomery-Åsberg Depression Rating Scale (MADRS) was achieved. Cognition (Mini Mental State Examination) and psychomotor changes (CORE Assessment) were monitored at baseline and 1 week after the last session of ECT. We performed 3 T structural MRI at both time points. We used the VBM8 toolbox in SPM8 to study grey matter volume changes. Paired t tests were used to compare pre- and post-ECT grey matter volume (voxel-level family-wise error threshold p < 0.05) and to assess clinical response.

RESULTS

Twenty-eight patients (mean age 71.9 ± 7.8 yr, 8 men) participated in our study. Patients received a mean of 11.2 ± 4 sessions of ECT. The remission rate was 78.6%. Cognition, psychomotor agitation and psychomotor retardation improved significantly (p < 0.001). Right-hemispheric grey matter volume was increased in the caudate nucleus, medial temporal lobe (including hippocampus and amygdala), insula and posterior superior temporal regions but did not correlate with MADRS score. Grey matter volume increase in the caudate nucleus region correlated significantly with total CORE Assessment score (r = 0.63; p < 0.001).

LIMITATIONS

Not all participants were medication-free.

CONCLUSION

Electroconvulsive therapy in patients with LLD is associated with significant grey matter volume increase, which is most pronounced ipsilateral to the stimulation side.

Cognitive Behavioral Therapies in older adults with depression and cognitive deficits: a systematic review

OBJECTIVES

The objective of this study is to investigate the effectiveness of cognitive behavioral therapies (CBTs) in improving depressive symptoms, disability, and cognition in older adults with depression and cognitive deficits.

DESIGN

It was performed a systematic search for articles published between 1994 and February 2014 in the MEDLINE/Pubmed, PsycINFO, and SCIELO. The studies should have provided information about benefits after CBTs to older adults with depression and cognitive deficits.

RESULTS

Cognitive behavioral therapy focused on problem solving is the main approach studied, having better effectiveness than supportive therapy in randomized clinical trials. Significant improvements in mood and disability were consistent, although evidence of changes in cognitive measures is controversial, less studied, and limited. Nevertheless, improvements in executive functions, processing speed, and changes in patients' perspectives of problem solving skills, such as generating alternatives and decision-making, were described. Also, it would be necessary that future studies more often evaluate cognitive status of depressed elders, as well as cognitive changes after psychotherapy. It should be emphasized that there is a lack of studies in this field, and more approaches in CBTs need to be investigated to this population.

CONCLUSION

Older adults with depression and cognitive deficits can benefit from CBTs. Improvements in mood and disability are more consistent than changes in cognition, which are little studied after CBTs. It is necessary more studies in the field, as well as, to investigate more approaches in CBTs to older adults with depression and cognitive deficits.

Structural imaging in late-life depression: association with mood and cognitive responses to antidepressant treatment

OBJECTIVES

Recent positron emission tomography studies of cerebral glucose metabolism have identified the functional neural circuitry associated with mood and cognitive responses to antidepressant treatment in late life depression (LLD). The structural alterations in these networks are not well understood. The present study used magnetic resonance (MR) imaging and voxel-based morphometry to evaluate the association between gray matter volumes and changes in mood symptoms and cognitive function with treatment with the antidepressant citalopram.

DESIGN

Open-label trial with baseline brain MR scan. Mood and cognitive assessments performed at baseline and during citalopram treatment.

SETTING

Outpatient clinics of an academic medical center.

PARTICIPANTS

17 previously unmedicated patients age 55 years or older with a major depressive episode and 17 non-depressed comparison subjects.

INTERVENTION

12-week trial of flexibly dosed citalopram.

MEASUREMENTS

Gray matter volumes, Hamilton Depression Rating Scale, California Verbal Learning Test, Delis-Kaplan Executive Function System.

RESULTS

In LLD, higher gray matter volumes in the cingulate gyrus, superior and middle frontal gyri, middle temporal gyrus, and precuneus was associated with greater mood improvement. Higher gray matter volumes in primarily frontal areas were associated with greater improvement in verbal memory and verbal fluency performance.

CONCLUSIONS

Associations with antidepressant induced improvements in mood and cognition were observed in several brain regions previously correlated with normalization of glucose metabolism after citalopram treatment in LLD. Future studies will investigate molecular mechanisms underlying these associations (e.g., beta-amyloid, inflammation, glutamate).

Depressive symptoms, symptom dimensions, and white matter lesion volume in older adults: a longitudinal study

OBJECTIVE

White matter lesions (WMLs) are associated with depressive symptoms in older adults. However, it is not clear whether different symptom dimensions of depression have distinct associations with WMLs. The authors assessed the longitudinal relationships of the Center for Epidemiologic Studies Depression Scale (CES-D) total score and subscale scores with WML volume in the Baltimore Longitudinal Study of Aging.

METHODS

Using a prospective observational design, the authors examined WML volume and depressive symptoms at 1- to 2-year intervals for up to 9 years in 116 dementia-free participants (mean age: 68.78 ± 7.68). At each visit, depressive symptoms were measured with the CES-D and WML volumes were quantified from structural magnetic resonance imaging scans.

RESULTS

Higher CES-D full-scale scores were associated with greater WML volume and with a faster rate of volume increases over time in women, especially at older ages. Higher depressed mood and somatic symptoms subscale scores were associated with greater increases in WML volume over time at older ages. In men, depressed mood and somatic symptoms were associated with larger WML volume at baseline.

CONCLUSION

Findings confirm an association between WMLs and depressive symptoms and suggest that depressed mood and somatic symptoms may be stronger predictors of depression-related brain changes than lack of well-being. Age and sex may moderate the relationships between depressive symptoms and WMLs. Understanding particular symptom dimensions of depressive symptoms has implications for treatment and may lead to targeted interventions and more precise knowledge of mechanisms underlying depression.

Effects of the coexistence of late-life depression and mild cognitive impairment on white matter microstructure

BACKGROUND AND OBJECTIVE

Late-life depression (LLD) and amnestic mild cognitive impairment (aMCI) are associated with white matter (WM) disruptions of the fronto-limbic and interhemispheric tracts implicated in mood regulation and episodic memory functions. This work investigates the extent of these WM abnormalities in patients LLD and aMCI when these diseases occur alone and when they coexist.

MATERIALS AND METHODS

Eighty-four subjects separated into cognitively normal (n=33), LLD (n=20), aMCI (n=18), and comorbid aMCI and LLD (n=13) completed Diffusion Tensor Imaging (DTI) scans. Tract-based spatial statistics was employed to skeletonize multiple DTI indices of the cingulum, corpus callosum, fornix and uncinate fasciculus. Analysis of covariance and post-hoc tests compared group differences. Multiple linear regressions were performed between DTI and behavioral measures for the whole sample and within individual patient groups.

RESULTS

Divergent microstructural disruptions were identified in LLD- and aMCI-only groups, whereas the comorbid group showed widespread abnormalities especially in the hippocampal cingulum and fornix tracts. The LLD groups also showed significant disruptions in the uncinate fasciculus and corpus callosal tracts. Higher depressive symptom and lower episodic memory scores were associated with increased diffusivity measures in the fornix and hippocampal cingulum across all subjects.

CONCLUSIONS

Widespread WM microstructural disruptions are present when LLD and aMCI are comorbid -especially in the medial temporal lobe tracts. These WM disruptions may be a marker of disease severity. Also, multiple DTI parameters should be used when evaluating the WM fiber integrity in LLD and aMCI.

What are the causes of late-life depression?

Although depression in old age is less common than depression in younger populations, it still affects more than 1 million community-living older adults. Depression in late life has been associated with reduced quality of life and increased mortality from both suicide and illness. Its causes are multifactorial but are prominently related to both biologic and social factors. Psychological factors, although less studied in elders, are also important in understanding its cause. In this article, multiple facets of late-life depression are reviewed, including its clinical presentation, epidemiology, and biopsychosocial causes.

Late-life depression, mild cognitive impairment and hippocampal functional network architecture

Late-life depression (LLD) and amnestic mild cognitive impairment (aMCI) are associated with medial temporal lobe structural abnormalities. However, the hippocampal functional connectivity (HFC) similarities and differences related to these syndromes when they occur alone or coexist are unclear. Resting-state functional connectivity MRI (R-fMRI) technique was used to measure left and right HFC in 72 elderly participants (LLD [n = 18], aMCI [n = 17], LLD with comorbid aMCI [n = 12], and healthy controls [n = 25]). The main and interactive relationships of LLD and aMCI on the HFC networks were determined, after controlling for age, gender, education and gray matter volumes. The effects of depressive symptoms and episodic memory deficits on the hippocampal functional connections also were assessed. While increased and decreased left and right HFC with several cortical and subcortical structures involved in mood regulation were related to LLD, aMCI was associated with globally diminished connectivity. Significant LLD-aMCI interactions on the right HFC networks were seen in the brain regions critical for emotion processing and higher-order cognitive functions. In the interactive brain regions, LLD and aMCI were associated with diminished hippocampal functional connections, whereas the comorbid group demonstrated enhanced connectivity. Main and interactive effects of depressive symptoms and episodic memory performance were also associated with bilateral HFC network abnormalities. In conclusion, these findings indicate that discrete hippocampal functional network abnormalities are associated with LLD and aMCI when they occur alone. However, when these conditions coexist, more pronounced vulnerabilities of the hippocampal networks occur, which may be a marker of disease severity and impending cognitive decline. By utilizing R-fMRI technique, this study provides novel insights into the neural mechanisms underlying LLD and aMCI in the functional network level.

[Anxiety and depression in the elderly]

OBJECTIVES

This paper deals with diagnostics and prevalence of depression and anxiety in the elderly, their biological, psychological, and social risk factors, and the effectiveness of psychotherapy and pharmacotherapy.

METHODS

The results are based on an overview of the literature reflecting reviews and meta-analyses.

RESULTS

In the elderly, there is a substantial danger of confounding psychogenic with medical or drug-induced symptoms. Self-assessment scales may be useful for screening, but the results should be confirmed by an expert interview. Based on the available research, we cannot yet be sure whether the prevalence of depression and anxiety in the elderly population is in fact higher, lower, or equal to younger age groups. More women are afflicted with depression or anxiety than men. Pharmacotherapy (preferably antidepressants) and psychotherapy are effective for treating anxiety and depression in the elderly, with medium to high effect sizes. To date it is not possible to provide evidence-based treatment recommendations for the type or the setting of psychotherapy.

DISCUSSION

More research on this topic is needed.

Microstructural damage of the posterior corpus callosum contributes to the clinical severity of neglect

One theory to account for neglect symptoms in patients with right focal damage invokes a release of inhibition of the right parietal cortex over the left parieto-frontal circuits, by disconnection mechanism. This theory is supported by transcranial magnetic stimulation studies showing the existence of asymmetric inhibitory interactions between the left and right posterior parietal cortex, with a right hemispheric advantage. These inhibitory mechanisms are mediated by direct transcallosal projections located in the posterior portions of the corpus callosum. The current study, using diffusion imaging and tract-based spatial statistics (TBSS), aims at assessing, in a data-driven fashion, the contribution of structural disconnection between hemispheres in determining the presence and severity of neglect. Eleven patients with right acute stroke and 11 healthy matched controls underwent MRI at 3T, including diffusion imaging, and T1-weighted volumes. TBSS was modified to account for the presence of the lesion and used to assess the presence and extension of changes in diffusion indices of microscopic white matter integrity in the left hemisphere of patients compared to controls, and to investigate, by correlation analysis, whether this damage might account for the presence and severity of patients' neglect, as assessed by the Behavioural Inattention Test (BIT). None of the patients had any macroscopic abnormality in the left hemisphere; however, 3 cases were discarded due to image artefacts in the MRI data. Conversely, TBSS analysis revealed widespread changes in diffusion indices in most of their left hemisphere tracts, with a predominant involvement of the corpus callosum and its projections on the parietal white matter. A region of association between patients' scores at BIT and brain FA values was found in the posterior part of the corpus callosum. This study strongly supports the hypothesis of a major role of structural disconnection between the right and left parietal cortex in determining 'neglect'.