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Cerebral hemodynamics and cognitive performances in bilateral asymptomatic carotid stenosis.
No full textCerebral hemodynamics and cognitive performance in bilateral asymptomatic carotid
stenosis.
Balucani C, Viticchi G, Falsetti L, Silvestrini M.
From the Department of Neurology (C.B.), University of Perugia, Perugia, Italy;
Department of Neurology and Stroke Center (C.B.), SUNY Downstate Medical Center,
Brooklyn, NY; Neurological Clinic (G.V., M.S.), Marche Polytechnic University,
Ancona; and Internal and Subintensive Medicine (L.F.), Ospedali Riuniti, Ancona,
Italy.
OBJECTIVES: To evaluate cognitive performance in subjects with bilateral
asymptomatic carotid stenosis (B-ACS) compared to subjects with unilateral ACS
and to subjects with no carotid stenosis (CS) and to explore the relationship
between cognitive performance and cerebral hemodynamics status in B-ACS. METHODS:
The neuropsychological investigation included phonemic (ph) and categorical (ca)
Verbal Fluency (VF) tests for exploring the left brain functions and Colored
Progressive Matrices (CPM) and Complex Figure Copy Test (CFCT) for the right
brain. Cerebral hemodynamics status was assessed using the transcranial
Doppler-based breath-holding index test. RESULTS: A total of 333 subjects were
included: 127 B-ACS, 73/77 left/right unilateral ACS, 56 no CS, mean age 70 ±
3.78 years, 65% male. Subjects with B-ACS and subjects with unilateral ACS showed
significantly lower scores in all cognitive tests compared to subjects with no CS
(p < 0.05). Subjects with B-ACS with left impaired hemodynamics status showed a
significantly reduced ph-VF score, from 13.4 (95% confidence interval [CI]
11.2-15.8) to 7.5 (95% CI 5.4-9.7), and a reduced ca-VF score, from 19.7 (95% CI
18.1-24.1) to 10.8 (95% CI 9.5-15.1), compared to subjects with no CS. Similarly,
impaired cerebral hemodynamics in the right side was associated with a
significantly reduced CPM score, from an estimated mean of 34.2 (95% CI
29.8-35.4) to 24.6 (95% CI 20.2-25.8), and CFCT score from 37.0 (95% CI
32.0-37.4) to 27.1 (95% CI 23.3-28.7). All comparisons were p < 0.05. CONCLUSION:
Subjects with B-ACS and subjects with unilateral ACS are more likely to have
cognitive dysfunction compared to subjects with no CS. There appears to be a link
between cognitive dysfunction and hemodynamics impairment due to carotid
stenosis
Journal of Alzheimer's Disease
No full textThe Journal of Alzheimer's Disease (JAD) is an international multidisciplinary journal to facilitate progress in understanding the etiology, pathogenesis, epidemiology, genetics, behavior, treatment and psychology of Alzheimer's disease. The journal publishes research reports, reviews, short communications, hypotheses, ethics reviews, book reviews, and letters-to-the-editor. The journal is dedicated to providing an open forum for original research that will expedite our fundamental understanding of Alzheimer's disease
A data-driven clinical prediction rule for pulmonary embolism
No full textPurpose: Pulmonary embolism (PE), a life-threatening emergency is underdiagnosed because of a non-specific presentation.First-level exams (clinical exhamination, electrocardiography, blood gas analysis and laboratory tests)have low sensitivity and specificity.Clinical prediction rulers (CPRs)such as Wells and Geneva Revised, have been derived from different combinations of these exams.
Our aim was to perform a comparison between the two score systems in our population and to derive a new CPR using an Artificial Neural Network (ANN).
Methods: We enrolled 755 consecutive outpatients with suspect of PE (351 males, mean age 71±14years) and analyzed 24 clinical,instrumental and laboratoristic variables and Wells and Geneva scores.Logistic regression with ROC curves was used to evaluate the the diagnostic reliability of the scores. To derive the new classifier,the dataset was first split (in supervised classification step)into a train and a test subset containing 2/3 ad 1/3 of the patients' dataset,respectively.To find the optimal configuration of the new classifier we tested two different ANNs:a non-linear feed-forward ANN with back-propagation and a Levenberg-Marquardt network.For both we fixed the topological configurations of the network (one hidden layer,one output neuron)and stressed the system to find the optimal number of neurons in the hidden layer for the best configuration among highest AUC with the highest number of hit in the validation process and the minimum epochs.We repeated this study changing the dimension of the input dataset in two ways:excluding interactively some features or performing the reduction of the dimensionality of the feature space with principal component analysis. The application of the trained ANN to a "map set" gave,for each patient,the probability of belonging to the "pathological" or "healthy" class, obtaining the new CPR.Automatic classifications were compared with the manual ones, calculating the Jaccard coefficient, giving a measure of the quality. The system was implemented in Matlab using Neural Network toolboxes and PRTools.
Results: In our population,Wells performed better than Revised Geneva (AUC 0.75%,0.63%,respectively),while our CPR (feed-forward ANN with back-propagation) obtained an average AUC of 0.86% from the train set and Jaccard coefficient 0.86 from the map set.The optimal ANN configuration was with 3 neurons in the hidden layer.The difference among the three ROC curves resulted statistically significant.
Conclusions: An ANN-based CPR performs better in the clinical prediction of PE than classical rulers without increasing the number of items required for the analysis
The role of Framingham risk score in the progression from mild cognitive impairment to dementia
No full textBackground: Mild cognitive impairment (MCI) often represents the clinical
manifestation of cognitive deterioration preceding Alzheimer’s disease
(AD). Currently, there are no reliable approaches for an objective evaluation
of the risk of developing AD in patients affected by amnestic MCI (aMCI).
Objective: The aim of this study was to verify whether the Framingham
cardiovascular risk profile (FCRP) could be useful to identify patients at the
highest risk of conversion from MCI to AD.
Methods: Patients with aMCI were carefully investigated to assess their
vascular risk profile. They were also submitted to a comprehensive neuropsychological
evaluation. FCRP was calculated for each patient and apolipoprotein
E (ApoE) genotype was determined from peripheral blood cells.
The main outcome was defined as a conversion to AD within 24 months after inclusion.
Results: 385 consecutive aMCI subjects were included. Age, FCRP, and
vascular age showed a fairly predictive value on conversion to AD. Selecting
the subpopulation of ApoE ε4 carriers, we observed that FCRP had an
increased performance in predicting the conversion. The rate of conversion
increased from 12.5% in the FCRP low-risk group to 43.2% in the high-risk
group (p < 0.0001). ApoE ε4 carriers had a 3.7-times increased probability
of conversion with respect to the other subjects (p < 0.0001).
Conclusions: FCRP assessment could be considered a reliable approach
to predict conversion to AD in aMCI subjects. The presence of ApoE ε4
increases significantly the risk of conversion. These data confirm the narrow
relationship between genetic and vascular risk factors in influencing the
evolution of cognitive impairment
A new method for free testosterone assay: clinical evaluation.
No full textThe Authors propose a new direct method for the determination of free Testosterone (F.Te). Our study was made following this method: 1) on a control group composed of 12 healthy men and 21 healthy women, and 2) on a group of 29 patients suffering from Polycystic Ovary Syndrome (PCOS) with clinical signs of hyperandrogenism. This pathological group presented acne and hirsutism in 95% of the cases. The Authors demonstrate how the determination of F.Te permits a 93.1% correct endocrinological diagnosis of hyperandrogenism
Telecardiology over TCP/IP between Italy and Tunisia
No full textIn this paper we aim to illustrate our electrocardiographic
teleconsulting system based on an
asynchronous architecture with a central server
which uses a simply TCP/IP connection. In the last
years our Internal Medicine Department has developed
a cardiological, echocardiographic and electrocardiographic
consulting activity in the covered
areas. The ....
Cerebral hemodynamics and cognitive performance in bilateral asymptomatic carotid stenosis (letter)
No full textAndrogens, insulin-like growth factor-I (IGF-I), and carrier proteins (SHBG, IGFBP-3) in postmenopause.
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