Barbera van Harten

Brain Imaging in Patients With Diabetes A systematic review

Diabetes is associated with impaired cognitive functioning and an increased risk of dementia (1,2). Patients with type 1 diabetes may show mild to moderate slowing of mental speed and diminished mental flexibility, whereas learning and memory are relatively spared (3). In patients with type 2 diabetes, cognitive impairment may be relatively more pronounced, particularly affecting verbal memory or complex information processing (4,5). The pathogenesis is still uncertain, but chronic hyperglycemia, vascular disease, repeated hypoglycemic episodes, and possibly direct effects of insulin on the brain have been implicated (6). Brain imaging studies can help to clarify the pathogenesis. An increasing number of studies report both focal vascular and more global (e.g., atrophy) cerebral changes, but the results are not always consistent. Our aim was to systematically review brain imaging studies in patients with diabetes. Data on the relation of imaging with cognition and with relevant disease variables were also recorded. Medline and EMBASE (1966 to February 2006) were searched with the following medical subject heading terms: computed tomography (CT) and magnetic resonance imaging (MRI) studies: white matter, leukoaraiosis, lacunar infarction, subcortical, periventricular, brain, cerebral, hippocampus, atrophy, MRI, magnetic resonance imaging, CT, and tomography; magnetic resonance spectroscopy (MRS) studies: magnetic resonance spectroscopy, MRS, brain, and cerebral; positron emission tomography (PET), single-photon emission CT (SPECT), and Xenon-enhanced CT studies: cerebral blood flow, glucose metabolism, brain, cerebral, PET, SPECT, Xenon, positron emission tomography, single-photon emission tomography, and tomography; all combined with “diabetes.” The abstracts were screened and potentially relevant articles retrieved. These articles were included if they met the following four criteria: 1 ) original article, written in English, on brain imaging in adult patients with diabetes in comparison with control subjects; 2 ) diagnostic criteria for diabetes specified; 3 ) sample size of at least 20 diabetic patients, or a total sample …

Profile of Cognitive Impairment in Chronic Heart Failure

OBJECTIVES: To determine the frequency and pattern of cognitive dysfunction in outpatients with chronic congestive heart failure (CHF) and to identify the corresponding demographic and clinical correlates.

Fragmentation of the rest-activity rhythm correlates with age-related cognitive deficits

Aging affects both cognitive performance and the sleep‐wake rhythm. The recent surge of studies that support a role of sleep for cognitive performance in healthy young adults suggests that disturbed sleep‐wake rhythms may contribute to ‘age‐related’ cognitive decline. This relationship has however not previously been extensively investigated. The present correlational study integrated a battery of standardized cognitive tests to investigate the association of mental speed, memory, and executive function with actigraphically recorded sleep‐wake rhythms in 144 home‐dwelling elderly participants aged 69.5 ± 8.5 (mean ± SD). Multiple regression analyses showed that the partial correlations of the fragmentation of the sleep‐wake rhythm with each of the three cognitive domains (r = −0.16, −0.19, and −0.16 respectively) were significant. These associations were independent from main effects of age, implying that a unique relationship between the rest‐activity rhythm and cognitive performance is present in elderly people.

Brain magnetic resonance imaging abnormalities in patients with heart failure

Although heart failure (HF) is a common cardiovascular disorder, to date little research has been conducted into possible associations between HF and structural abnormalities of the brain.

Brain lesions on MRI in elderly patients with type 2 diabetes mellitus.

Background and Purpose: Diabetes mellitus (DM) type 2 has been associated with poor cognitive performance and dementia, particularly in elderly patients. The exact mechanisms underlying the cognitive dysfunction in DM remain unclear. Imaging studies of the brain could be helpful to give more insight into possible structural brain lesions underlying these cognitive dysfunctions. Therefore, we performed a study in independently living patients with DM type 2 in order to investigate the association between DM and brain imaging abnormalities. Methods: The study population consisted of 45 patients with DM type 2 without hypertension (mean age 73.4 ± 5.1 years, mean duration 16.5 ± 11.5 years), 45 patients with DM type 2 and hypertension (mean age 73.5 ± 6.1 years, mean duration 11.9 ± 9.2 years) and 44 control subjects (mean age 73.1 ± 5.4 years). All patients and control subjects underwent an MRI of the brain. White matter lesions (WML), cerebral atrophy and medial temporal lobe atrophy were rated by a standardized visual rating scale. Lacunar infarcts were defined as focal hypo-intensities on fluid-attenuated inversion recovery sequences with a hyperintense rim around it. Results: WML occurred more frequently in diabetic patients with hypertension as well as without hypertension. Significantly more deep WML were found in DM patients with and without hypertension when compared to control subjects, whereas no difference was found in the occurrence of periventricular hyperintensities. In all 3 groups, lacunar infarcts occurred sporadically. A trend towards higher atrophy scores was seen in patients with DM compared to control subjects. Conclusions: The data of this cross-sectional study suggest that type 2 DM is an independent risk factor for deep WML in the independently living elderly patients.

The role of white matter hyperintensities and medial temporal lobe atrophy in age-related executive dysfunctioning.

Various studies support an association between white matter hyperintensities (WMH) and deficits in executive function in nondemented ageing. Studies examining executive functions and WMH have generally adopted executive function as a phrase including various functions such as flexibility, inhibition, and working memory. However, these functions include distinctive cognitive processes and not all may be affected as a result of WMH. Furthermore, atrophy of the medial temporal lobe (MTA) is frequently observed in ageing. Nevertheless, in previous studies of nondemented ageing MTA was not considered when examining a relationship between white matter and executive function. The goal of the present study was to examine how WMH and MTA relate to a variety of executive functions, including flexibility, fluency, inhibition, planning, set shifting, and working memory. Strong correlations were observed between WMH and MTA and most of the executive functions. However, only MTA was related to flexibility and set shifting performance. Regression analysis furthermore showed that MTA was the strongest predictor of working memory, after which no further significant association with WMH was noted. Alternatively, both MTA and periventricular hyperintensities independently predicted inhibition performance. These findings emphasize the importance of MTA when examining age-related decline in executive functioning.

Pain intensity and pain affect in relation to white matter changes.

&NA; Since aging is a risk factor for both dementia and the occurrence of painful conditions, with the number of aged people increasing in the next decades, an increase in the number of elderly people suffering from both conditions can be anticipated. Reliable pain assessment in this population is restricted by reduced communicative and cognitive capacity, with serious consequences for effective pain treatment. White matter changes are frequently observed in the various subtypes of dementia as well as in normal aging, and may play a crucial role in pain processing. In healthy elderly people, reliable pain assessment can be accomplished, which enables examining the relationship between pain experience and white matter changes. A normal structure and function of the white matter is extremely important for dorsolateral prefrontal cortex (DLPFC) functioning, which has recently been linked to pain inhibition. The present study focused on the relation between white matter changes and both pain intensity and pain affect in elderly people without dementia. The Coloured Analogue Scale (CAS) and the Number of Words Chosen‐Affective (NWC‐A) were applied to measure pain intensity and pain affect, respectively. The presence of white matter changes was significantly related to a higher score on the NWC‐A but not the CAS score. These results suggest that pain experience may change as a result of aging and that white matter changes might be indicative for these alterations.

Validation of the HIV Dementia Scale in an Elderly Cohort of Patients with Subcortical Cognitive Impairment Caused by Subcortical Ischaemic Vascular Disease or a Normal Pressure Hydrocephalus

Introduction: Most cognitive screening instruments are tailored to detect symptoms of cortical dysfunction in the elderly. Therefore, subcortical cognitive dysfunction may be missed using these tests. The aim of this study was to validate the Human Immunodeficiency Virus (HIV) Dementia Scale (HDS), a screening test developed to detect subcortical cognitive dysfunction in young HIV-infected patients, in a group of elderly patients with subcortical cognitive impairment (SCI) caused by subcortical ischaemic vascular disease (SIVD) or a normal pressure hydrocephalus (NPH). Materials and Methods:53patients with SCI caused by SIVD or an NPH and 54 age-matched control subjects without cognitive impairment were included. All subjects underwent the HDS and the Mini-Mental State Examination (MMSE). A neuropsychological examination was used as the best reference test for the diagnosis of SCI. Results: The mean HDS score (maximum 16) was 5.1 ± 3.5 in the SCI patients and 13.0 ± 2.4 in the controls (p < 0.0001). The mean MMSE score (maximum 30) was 26.5 ± 3.1 in the SCI group and 28.6 ± 1.4 in the controls (p < 0.0001). Among subjects who had an MMSE score of more than 26 points, SCI patients (n = 35) also scored significantly lower on the HDS than controls (n = 50), mean scores being 6.2 ± 3.4 and 13.0 ± 2.4, respectively (p < 0.0001). A receiver-operating characteristics curve was used to detect the optimal sensitivity and specificity of the HDS. A cut-off score of 9 yielded 91% sensitivity (95% CI: 79–97) and 96% specificity (95% CI: 87–99). With this cut-off score, the positive predictive value was 96% (95% CI: 86–99) and the negative predictive value was 91% (95% CI: 81–97). Conclusions: These results suggest that the HDS is able to detect SCI in an elderly population with SIVD or NPH and a normal MMSE score, and warrant its further development as a screening tool for SCI.

White matter hyperintensities and working memory: an explorative study

ABSTRACT White matter hyperintensities (WMH) are commonly observed in elderly people and may have the most profound effect on executive functions, including working memory. Surprisingly, the Digit Span backward, a frequently employed working memory task, reveals no association with WMH. In the present study, it was investigated whether more detailed analyses of WMH variables and study sample selection are important when establishing a possible relationship between the Digit Span backward and WMH. To accomplish this, the Digit Span backward and additional working memory tests, WMH subscores, and cardiovascular risk factors were examined. The results revealed that performance on the Digit Span backward test is unrelated to WMH, whereas a relationship between other working memory tests and WMH was confirmed. Furthermore, a division between several white matter regions seems important; hyperintensities in the frontal deep white matter regions were the strongest predictor of working memory performance.