Meltem Halil

Assessment of Endothelial Function in Alzheimer's Disease: Is Alzheimer's Disease a Vascular Disease?

OBJECTIVES: To compare endothelial function of people with Alzheimers disease (AD) with that of people without.

Comprehensive assessment of malnutrition risk and related factors in a large group of community-dwelling older adults.

BACKGROUND & AIMS Older adults are poorly assessed for malnutrition risk although malnutrition is not an uncommon problem in this population. The aim of this study was to determine the malnutrition risk and its correlates in geriatric outpatients. METHOD The study was performed in 2327 patients > or =65 years old who were admitted to our Geriatric Medicine outpatient clinic. Together with comprehensive geriatric assessment, nutritional assessment with short version of mini nutritional assessment test (MNA-SF) was performed. MNA-SF score < or =11 was determined as malnutrition risk. RESULTS Mean age of patients was 72.14+/-6.11 and 1479 (63.6%) were female. Mean MNA-SF score was 12.31+/-2.18. The number of patients with MNA-SF score < or =11 was 651 (28%). Depression, haematocrit, plasma fasting glucose, albumin, erythrocyte sedimentation rate, instrumental activities of daily living scores and bone mineral density measured from total femur were found to be significantly associated with malnutrition risk. CONCLUSION In this study malnutrition risk was detected in 651 (28%) patients. This ratio was similar to the literature. In older adults malnutrition risk is found to be increased due to majority of chronic illnesses and physical dependency. In conclusion, nutritional assessment should be a part of comprehensive geriatric assessment.

Cognitive aspects of frailty: Mechanisms behind the link between frailty and cognitive impairment

Whereas physical impairment is the main hallmark of frailty, evidence suggests that other dimensions, such as psychological, cognitive and social factors also contribute to this multidimensional condition. Cognition is now considered a relevant domain of frailty. Cognitive and physical frailty interact: cognitive problems and dementia are more prevalent in physically frail individuals, and those with cognitive impairment are more prone to become frail. Disentangling the relationship between cognition and frailty may lead to new intervention strategies for the prevention and treatment of both conditions. Both frailty and cognitive decline share common potential mechanisms. This review examines the relationship between frailty and cognitive decline and explores the role of vascular changes, hormones, vitamin D, inflammation, insulin resistance, and nutrition in the development of physical frailty and cognitive problems, as potential underlying mechanisms behind this link. Dual tasking studies may be a useful way to explore and understand the relation between cognitive and physical frailty. Further studies are needed to elucidate this complex relation to improve the outcomes of frailty.

The Evaluation of Neutrophil-Lymphocyte Ratio in Alzheimer’s Disease

Background/Aim: There is growing consensus in the literature that inflammation plays a significant role in the pathophysiology of Alzheimer’s disease (AD). The blood neutrophil-lymphocyte ratio (NLR) is a new, inexpensive and easily applicable marker of inflammation. The aim of this study was to investigate the association between NLR, as an inflammatory biomarker, and AD. Methods: 241 AD patients and 175 patients with normal cognitive function were evaluated in this study. Results: The mean ± SD NLR of AD patients was significantly higher than that of patients with normal cognitive function (3.21 ± 1.35 vs. 2.07 ± 0.74, p < 0.001, respectively). Receiver operating characteristic curve analysis suggested that the optimum NLR cutoff point for AD was 2.48 with 69.29% sensitivity, 79.43% specificity, 82.30% positive predictive values and 65.30% negative predictive values. Logistic regression analysis showed that elevated NLR (OR: 4.774, 95% CI: 2.821–8.076, p < 0.001) was an independent variable for predicting AD. Conclusion: Elderly people with AD have higher NLR than healthy controls. Elevated NLR levels are usually considered as an inflammatory marker. The results of this study suggested that inflammation plays a role in the pathogenesis of AD.

The association between homocysteine (hcy) and serum natural antioxidants in elderly bone mineral densitometry (BMD).

Previous studies showed oxidative stress had an important impact on osteoclastic and osteoblastic functions. Oxidative stress or low levels of antioxidants are supposed to reduce BMD and cause osteoporosis. hcy, gamma glutamyltransferase (GGT), uric acid, albumin and total bilirubin are simple laboratory parameters that are related with oxidative stress. In this study we compare the serum hcy and antioxidant levels in patients with osteoporosis, osteopenia and control subjects. A total of 2190 elderly persons (1348 patients with osteoporosis, 643 patients with osteopenia and 199 control subjects) who were referred to the outpatient clinic of the Department of Internal Medicine, Division of Geriatric Medicine at Hacettepe University Hospital for comprehensive geriatric assessment were included in this cross-sectional study. Mean age of subjects were 72.30 ± 6.34 in osteoporosis group, 71.92 ± 6.90 in osteopenia and 71.86 ± 5.88 in control group (p: 0.260). Multivariate regression analysis revealed that hypertension (HT) (OR: 0.675, 95% CI: 0.534-0.854, p: 0.001), diabetes mellitus (DM) (OR: 1.669, 95% CI: 1.301-2.142, p: <0.001), age (OR: 1.025, 95% CI: 1.006-1.044, p: 0.009), male gender (OR: 0.451, 95% CI: 0.358-0.569, p<0.001), uric acid (OR: 0.893, 95% CI: 0.837-0.952, p: 0.001), hcy (OR: 1.042, 95% CI: 1.023-1.061, p<0.001), albumin (OR: 0.521, 95% CI: 0.376-0.724, p<0.001), GGT (OR: 1.010, 95% CI: 1.003-1.017, p: 0.003), creatinine (OR: 0.630, 95% CI: 0.459-0.864, p: 0.004) were independent variables predicting the occurrence of osteoporosis. This study shows there is an imbalance between natural antioxidative and oxidative markers in patients with osteoporosis. Higher serum uric acid and albumin levels are associated with a lower prevalence of osteoporosis whereas higher hcy and GGT levels are associated lower BMD and higher osteoporosis prevalence.

Hippocampal atrophy correlates with the severity of cognitive decline

BACKGROUND The aim of this study is to compare the results of magnetic resonance (MR) imaging, particularly the decline in hippocampal volume, of patients with Alzheimers disease (AD) and mild cognitive impairment (MCI) with healthy age-matched controls, to examine the reliability of hippocampal volumetry in the early diagnosis of AD and the correlation of the severity of hippocampal atrophy with the severity of cognitive decline. METHODS Twenty-six AD, 22 MCI and 15 normal cognitive status (NCS) patients were scanned with a 3 Tesla MR scanner. Hippocampus volumes were detected manually by Osiris 4.18. RESULTS Multivariate regression analysis, which was performed to adjust the covariate effects of education, age, gender, hypertension and diabetes mellitus, showed that hippocampal atrophy was correlated with AD and MCI for right hippocampus; AD, MCI and age for left hippocampus independent of other parameters. A second regression analysis revealed that MMSE was correlated with hippocampal volume. CONCLUSIONS Hippocampal volumetry can be used in early diagnosis of cognitive impairment, as well as grading cognitive decline.

Iron deficiency can cause cognitive impairment in geriatric patients

ObjectivesDeficiency of iron, which plays an important role in oxygen transport and storage, may lead to cerebral hypoxia and cognitive decline. This relationship which was studied in children and adults was not evaluated in the elderly. The objective of this study is to examine the effect of iron deficiency on cognitive function in the elderly.Design, Setting, ParticipantsThis is a cross-sectional study conducted in a geriatric medicine outpatient clinic of a university hospital. Consecutive 2009 patients admitted to Geriatric Medicine outpatient clinic were examined and 622 patients who fulfilled the inclusion criteria were enrolled in the study.MeasurementsComprehensive geriatric assessment, cognitive assessment and laboratory analysis including blood count, iron, total iron binding capacity, ferritin, and transferrin saturation were performed.ResultsMean age of the study group was 72.5±6.5 and 439 (70.6%) were women. MMSE scores were moderately and significantly correlated with iron levels (r=0.33, p<0.001) and transferrin saturation (r=0.32, p<0.001). Transferrin saturation was significantly lower in the patients with dementia (p=0.040). It was found that patients with iron deficiency had lower MMSE scores (p<0.001) and this relationship was also present in patients without anemia (p=0.004).ConclusionThe results of this study revealed a negative influence of iron deficiency on cognitive function and this influence was independent from the presence of anemia. As iron deficiency can be easily diagnosed and treated, detecting its effect on cognitive function is of importance. Screening for iron deficiency and initiating appropriate treatment should be a routine part of comprehensive geriatric assessment.

Altered Levels of Homocysteine and Serum Natural Antioxidants Links Oxidative Damage to Alzheimer's Disease

Increasing evidence supports the theory that oxidative stress plays an important role in the pathogenesis of Alzheimers disease (AD). Homocysteine (Hcy), uric acid (UA), bilirubin, and albumin are simple laboratory parameters that are related to oxidative stress. In this study we compared serum Hcy and antioxidant levels in patients with AD and normal cognitive function. In this cross-sectional study, 143 AD patients and 1,553 patients with normal cognitive function aged 65 years and over were enrolled. Mean values of UA and albumin levels of AD patients were significantly lower than normal cognitive function subjects (p: 0.003 versus p < 0.001, respectively). Mean value of Hcy levels of AD patients was significantly higher than normal cognitive function subjects (p = 0.031). Multivariate regression analysis revealed that Mini-nutritional assessment short form (OR: 0.905, 95% CI: 0.850-0.965, p = 0.002), hypertension (OR: 1.573, 95% CI: 1.148-2.155, p = 0.005), UA (OR: 0.879, 95% CI: 0.788-0.981, p = 0.021), Hcy (OR: 1.040, 95% CI: 1.022-1.059, p < 0.001), and albumin (OR: 0.505, 95% CI: 0.339-0.753, p < 0.001) were independent variables predicting the occurrence of AD. Our study supports the hypothesis that a decrease in antioxidants and an increase in oxidative damage are linked to AD.

Serum elevated gamma glutamyltransferase levels may be a marker for oxidative stress in Alzheimer's disease.

BACKGROUND Gamma glutamyltransferase (GGT) plays a role in cellular glutathione uptake, which is an important element of antioxidant mechanisms. An increase in serum GGT is thought to be an early and sensitive marker of oxidative stress. Oxidative stress has a role in the pathogenesis of Alzheimers disease (AD). The aim of this study was to investigate the GGT levels in AD. METHOD In this cross-sectional study, 132 patients with AD (mean age: 74.1 +/- 7.4, female 62.9%) and 158 age- and gender-matched normal controls (mean age: 74.5 +/- 6.3, female 67.1%) were evaluated. For cognitive assessment, MMSE and clock drawing tests were performed; DSM-IV and NINCDS-ADRDA criteria were used. Serum GGT, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase concentrations were determined. RESULTS Median (min-max) GGT levels were 18 (9-70) in AD group and 17 (5-32) in normal controls. Mann-Whitney U test showed that GGT levels were significantly higher in AD patients (p = 0.012). Linear regression analysis revealed AD was an independent correlate of elevated GGT levels. Hypertension, diabetes mellitus, total cholesterol, and low density lipoprotein cholesterol were not associated with GGT levels. CONCLUSION GGT levels were increased significantly in AD patients. To evaluate the role of GGT as a marker of oxidative stress in AD, further studies are needed.

Increased mean platelet volume (MPV) indicating the vascular risk in Alzheimer's disease (AD)

Vascular risk factors play a significant role in the pathogenesis and progression of AD. MPV is an index of platelet activation and may be a potential marker of inflammation to demonstrate the vascular damage in AD. The aim of the present study is to assess whether platelet volume would be useful in predicting vascular damage in AD. A total of 126 patients with AD (male/female: 44/82, mean age 76.2 ± 6.8 years) and 286 patients as controls with normal cognitive function (male/female: 123/163, mean age 75.2 ± 6.3 years) were enrolled in this cross-sectional study. MPV values were determined for all study participants. Mini-Mental State Examination (MMSE) and clock drawing tests (CDT) were performed for cognitive assessment, DSM-IV and NINCDS-ADRDA criteria were used for diagnosis of AD. The mean MPV values were significantly higher in AD group (8.46 ± 1.15 vs. 8.17 ± 0.90; p=0.011). In this study, significantly higher MPV values in patients with AD have been detected. Since increased MPV levels are usually considered as a vascular risk factor, the results of this study suggested the role of platelet activation in the vascular pathogenetic basis of AD.