Study of the relationship between serum cortisol and dehydroepiandrosterone sulfate [DHEAS] levels and degree of cognitive impairment in the aged with Alzheimer's disease and vascular dementia

Dementia is the general term that refers to the decline of mental abilities including memory and other thinking skills while a person is alert and awake. Dementia is considered a late-life disease because it tends to develop mostly in elderly people. The two most common forms of dementia in older people are Alzheimer's disease and multi-infarct dementia [vascular dementia]. Alzheimer's disease accounts for around 60% of all cases of dementia, while vascular dementia accounts for up to 20% of all cases of dementia. Cortisol and dehydroepiandrosterone [DHEA] and its sulfate ester [DHEAS] are adrenal steroid hormones. These hormones have been suggested to have a role in many aging related diseases and perhaps in aging itself. These hormones have been shown to multiple effects on the function of the hippocampus, which is involved in learning and memory processes. These adrenal steroids may thus be associated with cognitive impairment, which is a major symptom of dementia. To study the relationship between serum cortisol and dehydroepiandroesterone sulfate [DHEAS] levels and degree of cognitive impairment in the aged persons with Alzheimer's disease and vascular dementia. Study was conducted on 30 elderly demented patients selected randomly from the general population. Their ages ranged from 52 to 85 years with a mean of 68.5 years and they were 13 males and 17 females, they were divided into two groups; group I: 15 patients [7 males and 8 females] with probable Alzheimer's disease diagnosed according to diagnostic and statistical manual of mental disorder [DSM- IV criteria], group II: 15 patients [6 males and 9 females] with vascular dementia, group III consisted of 15 elderly healthy volunteers, matched for age and sex with no evidence of dementia have been served as control group. All were submitted to morning collection of blood for determination of the plasma cortisol and DHEAS measured by chemiilluminescence. The 30 points Mini Mental State Examination [MMSE] was used to assess cognition. The present study firstly showed that mean serum cortisol level increase while mean serum DHEAS level decrease with age and mean serum cortisol levels was higher in both AD and VD than normal controls while mean serum DHEAS levels in both AD and VD] was lower than normal controls. Gender did not play a significant role in variability of cortisol and DHEAS. Also, most of Alzheimer's disease patients were none educated in comparison to vascular dementia patients and this indicates that a low level of education has been associated with a greater risk of developing AD. There is an association between serum cortisol and DHEAS levels and severity and duration of dementia and cognitive decline in demented patients. There is a strong association between cortisol and DHEAS and prevalence of dementia in the elderly. There was a trend of high serum cortisol level in males and high serum DHEAS level in females but, gender did not play a significant role in variability of cortisol and DHEAS. Low level of education has been associated with a greater risk of developing dementia and there is association between serum cortisol and serum DHEAS levels and duration and severity of dementia

Renovascular disease and cognitive impairment in elderly: a novel risk maker

Renal artery stenosis is most commonly due to either fibromuscular dysplasia or atherosclerosis. Atherosclerosis accounts for 90 percent of cases of renal-artery stenosis. Renal-artery stenosis may occur alone [isolated anatomical renal-artery stenosis] or in association with hypertension, renal insufficiency [ischemic nephropathy], or both. The aim of the present work was to study the role of renovascular disease as a novel risk marker of cognitive impairment in elderly. The study included 80 patients divided into 4 groups: Group 1: 20 cases of elderly patients above 65 years and suffering from grade 2 or 3 CKD. Group II: 20 cases aged 20-40 years and suffering from grade 2 or 3 CKD. Group III: 20 healthy controls aged above 65 years. Group IV: 20 healthy controls aged 20-40. They had been evaluated for their: Clinical condition, including physical examination and history taking, ECG, BMI estimation, MMMS examination, Routine investigation including: complete blood picture with differential counting, bleeding and coagulation time, liver functions tests, lipid profile, fasting and post-prandial plasma glucose, renal function tests, complete urine analysis, 24-hours proteins in urine, assessment of glomerular filtration rate [GFR] by MDRD and creatinine clearance and in addition specific laboratory investigations were done including: Serum CRP using turbidimetry, Microalbuminurea using turbidimetry, v-WF Ag by ELISA, s-ICAM. By ELISA and Duplex study was performed on carotid and renal arteries. The results of the present study showed that there was a significant increase in the BMI in groups land II in comparison to group III which was higher than group IV. The MMMS test was significantly lower in group I in comparison to groups II and III which were in turn significantly lower than group IV. Hemoglobin was significantly lower in groups I and II than group III and IV. Platelets count was significantly lower in groups I and II than group III which was also significantly lower than group IV. Creatinine clearance was significantly lower in groups I and II than in groups III and IV vWF levels were significantly lower in groups land II than in groups III and IV s.ICAM I was significantly higher in groups I and II compared to groups Ill and IV. CRP was significantly increased in groups I and II in comparison to groups III and IV Carotid plaque score was significantly higher in group I than group II which was higher than groups III. Resistive index was significantly lower in groups land II than in groups III and IV Acceleration index was significantly lower in groups I and II than in groups III and IV. A significant positive correlation was found between age and urinary albumin, CRP, and s.ICAM. A significant negative correlation between age and cereatinine clearance and MDRD in groups I, II and III. Reno vascular disease is common in elderly and the most important cause is atherosclerosis in this group of patients. There are many risk factors for cognitive impairment in patients suffering from renovascular disease and most of them are correctable. Renovascular disease can be considered as a novel risk factor of cognitive impairment through many interacting mechanisms