Clinical characteristics in subcortical ischemic white matter disease

Altered static and dynamic functional network connectivity in Alzheimer's disease and subcortical ischemic vascular disease: shared and specific brain connectivity abnormalities

Subcortical ischemic vascular disease (SIVD) is a major subtype of vascular dementia with features that overlap clinically with Alzheimer's disease (AD), confounding diagnosis. Neuroimaging is a more specific and biologically based approach for detecting brain changes and thus may help to distinguish these diseases. There is still a lack of knowledge regarding the shared and specific functional brain abnormalities, especially functional connectivity changes in relation to AD and SIVD. In this study, we investigated both static functional network connectivity (sFNC) and dynamic FNC (dFNC) between 54 intrinsic connectivity networks in 19 AD patients, 19 SIVD patients, and 38 age-matched healthy controls. The results show that both patient groups have increased sFNC between the visual and cerebellar (CB) domains but decreased sFNC between the cognitive-control and CB domains. SIVD has specifically decreased sFNC within the sensorimotor domain while AD has specifically altered sFNC between the default-mode and CB domains. In addition, SIVD has more occurrences and a longer dwell time in the weakly connected dFNC states, but with fewer occurrences and a shorter dwell time in the strongly connected dFNC states. AD has both similar and opposite changes in certain dynamic features. More importantly, the dynamic features are found to be associated with cognitive performance. Our findings highlight similar and distinct functional connectivity alterations in AD and SIVD from both static and dynamic perspectives and indicate dFNC to be a more important biomarker for dementia since its progressively altered patterns can better track cognitive impairment in AD and SIVD.

Psychobiological factors of resilience and depression in late life

In contrast to traditional perspectives of resilience as a stable, trait-like characteristic, resilience is now recognized as a multidimentional, dynamic capacity influenced by life-long interactions between internal and environmental resources. We review psychosocial and neurobiological factors associated with resilience to late-life depression (LLD). Recent research has identified both psychosocial characteristics associated with elevated LLD risk (e.g., insecure attachment, neuroticism) and psychosocial processes that may be useful intervention targets (e.g., self-efficacy, sense of purpose, coping behaviors, social support). Psychobiological factors include a variety of endocrine, genetic, inflammatory, metabolic, neural, and cardiovascular processes that bidirectionally interact to affect risk for LLD onset and course of illness. Several resilience-enhancing intervention modalities show promise for the prevention and treatment of LLD, including cognitive/psychological or mind-body (positive psychology; psychotherapy; heart rate variability biofeedback; meditation), movement-based (aerobic exercise; yoga; tai chi), and biological approaches (pharmacotherapy, electroconvulsive therapy). Additional research is needed to further elucidate psychosocial and biological factors that affect risk and course of LLD. In addition, research to identify psychobiological factors predicting differential treatment response to various interventions will be essential to the development of more individualized and effective approaches to the prevention and treatment of LLD.

The course of apathy in late-life depression treated with electroconvulsive therapy; a prospective cohort study

OBJECTIVES

Apathy, a lack of motivation, is frequently seen in older individuals, with and without depression, with substantial impact on quality of life. This prospective cohort study of patients with severe late-life depression treated with electroconvulsive therapy (ECT) aims to study the course of apathy and the predictive value of vascular burden and in particular white matter hyperintensities on apathy course.

METHODS

Information on apathy (defined by a score of >13 on the Apathy Scale), depression severity, vascular burden, and other putative confounders was collected in at 2 psychiatric hospitals on patients with late-life depression (aged 55 to 87 years, N = 73). MRI data on white matter hyperintensities were available in 52 patients. Possible risk factors for apathy post-ECT were determined using regression analyses.

RESULTS

After treatment with ECT, 52.0% (26/50) of the depression remitters still suffered from clinically relevant apathy symptoms. In the entire cohort, more patients remained apathetic (58.9%) than depressed (31.5%). Presence of apathy post-ECT was not associated with higher age, use of benzodiazepines, or severity of apathy and depression at baseline. Less response in depressive symptomatology after ECT predicted post-treatment apathy. The presence of vascular disease, diabetes mellitus and smoking, and white matter hyperintensities in the brain was not associated with post-treatment apathy.

CONCLUSIONS

Apathy may perpetuate in individual patients, despite remission of depressive symptoms. In this cohort of patients with late-life depression, post-ECT apathy is not associated with white matter hyperintensities.

The role of early posttraumatic neuropsychological outcomes in the appearance of latter psychiatric disorders in adults with brain trauma

BACKGROUND

The objective was to determine the predictors of posttraumatic psychiatric disorders (PTPD) during the first 6 months following traumatic brain injury (TBI) focusing on neuroimaging, clinical and neuropsychological appraisements during acute and discharge phase of TBI.

MATERIALS AND METHODS

We designed a prospective, longitudinal study in which 150 eligible TBI patients were entered. Postresuscitation brain injury severity and discharged functional outcome were evaluated by standard clinical scales. First neuroimaging was done at a maximum of 24 h after head trauma. Early posttraumatic (PT) neuropsychological outcomes were assessed using Persian neuropsychological tasks at discharge. The standardized psychiatric assessments were carefully implemented 6 months postinjury. A total of 133 patients returned for follow-up assessment at 6 months. They were divided into two groups according to the presence of PTPD.

RESULTS

Apparently, aggression was the most prevalent type of PTPD (31.48%). There was no significant difference between groups regarding functional outcome at discharge. Diffuse axonal injury (12.96%) and hemorrhages (40.74%) within the cortex (42.59%) and sub-cortex (33.33) significantly occurred more prevalent in PTPD group than non-PTPD ones. Primary postresuscitation TBI severity, early PT lingual deficit and subcortical lesion on first scan were able to predict PTPD at 6 months follow-up.

CONCLUSION

Almost certainly, the expansive dissociation risk of cortical and subcortical pathways related to linguistic deficits due to severe intracranial lesions over a period of time can augment possibility of subsequent conscious cognitive-emotional processing deficit, which probably contributes to latter PTPD. Hence, early combined therapeutic supplies including neuroprotective pharmacotherapy and neurofeedback for neural function reorganization can dampen the lesion expansion and latter PTPD.

Neuroanatomical correlates of apathy in late-life depression and antidepressant treatment response

BACKGROUND

Apathy is a prominent feature of geriatric depression that predicts poor clinical outcomes and hinders depression treatment. Yet little is known about the neurobiology and treatment of apathy in late-life depression. This study examined apathy prevalence in a clinical sample of depressed elderly, response of apathy to selective serotonin reuptake inhibitor (SSRI) treatment, and neuroanatomical correlates that distinguished responders from non-responders and healthy controls.

METHODS

Participants included 45 non-demented, elderly with major depression and 43 elderly comparison individuals. After a 2-week single-blind placebo period, depressed participants received escitalopram 10mg daily for 12 weeks. The Apathy Evaluation Scale (AES) and 24-item Hamilton Depression Rating Scale (HDRS) were administered at baseline and 12 weeks. MRI scans were acquired at baseline for concurrent structural and diffusion tensor imaging of anterior cingulate gray matter and associated white matter tracts.

RESULTS

35.5% of depressed patients suffered from apathy. This declined to 15.6% (p<0.1) following treatment, but 43% of initial sufferers continued to report significant apathy. Improvement of apathy with SSRI was independent of change in depression but correlated with larger left posterior subgenual cingulate volumes and greater fractional anisotropy of left uncinate fasciculi.

LIMITATIONS

Modest sample size, no placebo control, post-hoc secondary analysis, use of 1.5T MRI scanner

CONCLUSIONS

While prevalent in geriatric depression, apathy is separable from depression with regards to medication response. Structural abnormalities of the posterior subgenual cingulate and uncinate fasciculus may perpetuate apathetic states by interfering with prefrontal cortical recruitment of limbic activity essential to motivated behavior.

The Extension of the German CERAD Neuropsychological Assessment Battery with Tests Assessing Subcortical, Executive and Frontal Functions Improves Accuracy in Dementia Diagnosis

BACKGROUND/AIMS

Alzheimer's disease (AD) is the most common form of dementia. Neuropsychological assessment of individuals with AD primarily focuses on tests of cortical functioning. However, in clinical practice, the underlying pathologies of dementia are unknown, and a focus on cortical functioning may neglect other domains of cognition, including subcortical and executive functioning. The current study aimed to improve the diagnostic discrimination ability of the Consortium to Establish a Registry for Alzheimer's Disease - Neuropsychological Assessment Battery (CERAD-NAB) by adding three tests of executive functioning and mental speed (Trail Making Tests A and B, S-Words).

METHODS

Logistic regression analyses of 594 normal controls (NC), 326 patients with mild AD and 224 patients with other types of dementia (OD) were carried out, and the area under the curve values were compared to those of CERAD-NAB alone.

RESULTS

All comparisons except AD-OD (65.5%) showed excellent classification rates (NC-AD: 92.7%; NC-OD: 89.0%; NC-all patients: 91.0%) and a superior diagnostic accuracy of the extended version.

CONCLUSION

Our findings suggest that these three tests provide a sensible addition to the CERAD-NAB and can improve neuropsychological diagnosis of dementia.

Vascular risk factors, depression, and cognitive change among African American older adults

OBJECTIVE

Vascular burden has been linked to future depression and cognitive change in predominately European American samples. This study investigated these relationships in older African Americans.

METHODS

To examine the connection between vascular risk factors, depression, and cognitive change, this study utilized data from 435 older African Americans. Specifically, the study examined the link between vascular risk at baseline with depression and cognitive functioning at a 2.5-year follow-up visit.

RESULTS

High baseline vascular risk was associated with increased odds of future depression while controlling for age and current depression. A series of path analyses demonstrated links between baseline vascular risk, increases in depression, and decreases in processing speed.

CONCLUSIONS

These findings suggest that African Americans with greater vascular burden are at greater risk for depression and cognitive change.

Tomada de decisão no IGT: estudo de caso pós-AVC de hemisfério direito versus esquerdo

Investigou comparativamente o processo de tomada de decisão de dois adultos pós-AVC unilateral e verificar o papel da lateralidade hemisférica na performance do Iowa Gambling Task (IGT). Participaram um adulto com lesão de hemisfério direito (LHD) e outro com lesão de hemisfério esquerdo (LHE), ambos pós-AVC isquêmico subcortical. O IGT foi utilizado para avaliar a tomada de decisão. Os pacientes apresentaram um desempenho adequado no IGT, demonstrando ter uma boa capacidade de tomar decisão. No entanto, somente o paciente com LHD apresentou uma curva sugestiva de aprendizagem. Esses dados indicam que uma lesão subcortical independente do hemisfério pode não interferir no desempenho do IGT. Sugere-se que estudos de grupos sejam conduzidos buscando comparar pacientes com lesão frontal e não-frontal, auxiliando na caracterização do processo de tomada de decisão na população com lesão vascular unilateral.

Vascular dementia: Cognitive, functional and behavioral assessment. Recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology. Part II

Vascular dementia (VaD) is the most prevalent form of secondary dementia and the second most common of all dementias. The present paper aims to define guidelines on the basic principles for treating patients with suspected VaD (and vascular cognitive impairment - no dementia) using an evidence-based approach. The material was retrieved and selected from searches of databases (Medline, Scielo, Lilacs), preferentially from the last 15 years, to propose a systematic way to assess cognition, function and behavior, and disease severity staging, with instruments adapted for our milieu, and diagnosis disclosure. The present proposal contributes to the definition of standard diagnostic criteria for VaD based on various levels of evidence. It is noteworthy that only around half of the population of patients with vascular cognitive impairment present with dementia, which calls for future proposals defining diagnostic criteria and procedures for this condition.