Artur Martins Novaes Coutinho

Changes in Neuropsychological Tests and Brain Metabolism After Bariatric Surgery

CONTEXT The mechanisms by which obesity alters the cerebral function and the effect of weight loss on the brain have not been completely clarified. OBJECTIVE The objective of the study was to assess the effect of bariatric surgery on the cognitive function and cerebral metabolism. DESIGN Seventeen obese women were studied prior to and 24 weeks after bariatric surgery using neuropsychological tests and positron emission tomography. SETTING The study was conducted in a reference center for the treatment of obesity of a Brazilian public university. PARTICIPANTS Thirty-three women paired by age and level of education made up two groups: 17 severely obese patients and 16 lean patients. They did not have diabetes mellitus or a family history of dementia. MAIN OUTCOME MEASURES Comparison of performance in neuropsychological tests and cerebral metabolism of the obese women before and after bariatric surgery was measured. The results found at the two moments were compared with those of the women of normal weight. RESULTS Women with a mean age of 40.5 years and mean body mass index of 50.1 kg/m(2) when compared with women with mean body mass index of 22.3 kg/m(2) showed increased cerebral metabolism, especially in the posterior cingulate gyrus (P < .004). No difference was found between the groups for the neuropsychological tests. After 24 weeks the cerebral metabolism of the obese women was lower, similar to the lean women, and there was an improvement of executive function, accompanying changes of metabolic and inflammatory parameters. CONCLUSIONS Obese women may have increased cerebral metabolism when compared with women of normal weight, and this appears to reverse after weight loss induced by bariatric surgery, accompanied by improved executive function.

Consistency of FDG-PET Accuracy and Cost-Effectiveness in Initial Staging of Patients With Hodgkin Lymphoma Across Jurisdictions

INTRODUCTION Two hundred ten patients with newly diagnosed Hodgkins lymphoma (HL) were consecutively enrolled in this prospective trial to evaluate the cost-effectiveness of fluorine-18 ((18)F)-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) scan in initial staging of patients with HL. METHODS All 210 patients were staged with conventional clinical staging (CCS) methods, including computed tomography (CT), bone marrow biopsy (BMB), and laboratory tests. Patients were also submitted to metabolic staging (MS) with whole-body FDG-PET scan before the beginning of treatment. A standard of reference for staging was determined with all staging procedures, histologic examination, and follow-up examinations. The accuracy of the CCS was compared with the MS. Local unit costs of procedures and tests were evaluated. Incremental cost-effectiveness ratio (ICER) was calculated for both strategies. RESULTS In the 210 patients with HL, the sensitivity for initial staging of FDG-PET was higher than that of CT and BMB in initial staging (97.9% vs. 87.3%; P < .001 and 94.2% vs. 71.4%, P < 0.003, respectively). The incorporation of FDG-PET in the staging procedure upstaged disease in 50 (24%) patients and downstaged disease in 17 (8%) patients. Changes in treatment would be seen in 32 (15%) patients. Cumulative cost for staging procedures was

Effects of Aerobic Training on Cognition and Brain Glucose Metabolism in Subjects with Mild Cognitive Impairment

3751/patient for CCS compared to

Brain metabolism and cerebrospinal fluid biomarkers profile of non-amnestic mild cognitive impairment in comparison to amnestic mild cognitive impairment and normal older subjects

5081 for CCS + PET and

Long-term lithium treatment reduces glucose metabolism in the cerebellum and hippocampus of nondemented older adults: an [¹⁸F]FDG-PET study.

4588 for PET/CT. The ICER of PET/CT strategy was

Differential associations between systemic markers of disease and cortical thickness in healthy middle-aged and older adults.

16,215 per patient with modified treatment. PET/CT costs at the beginning and end of treatment would increase total costs of HL staging and first-line treatment by only 2%. CONCLUSION FDG-PET is more accurate than CT and BMB in HL staging. Given observed probabilities, FDG-PET is highly cost-effective in the public health care program in Brazil.

Paraneoplastic limbic encephalitis with prominent neuropsychiatric apathy

BACKGROUND Aerobic training (AT) is a promising intervention for mild cognitive impairment (MCI). OBJECTIVE To evaluate the effects of AT on cognition and regional brain glucose metabolism (rBGM) in MCI patients. METHODS Subjects performed a twice-a-week, moderate intensity, AT program for 24 weeks. Assessment with ADAS-cog, a comprehensive neuropsychological battery, and evaluation of rBGM with positron emission tomography with 18F-fluorodeoxyglucose ([18F]FDG-PET) were performed before and after the intervention. Aerobic capacity was compared using the maximal oxygen consumption VO2max (mL/Kg/min). [18F]FDG-PET data were analyzed on a voxel-by-voxel basis with SPM8 software. RESULTS Forty subjects were included, with a mean (M) age of 70.3 (5.4) years and an initial Mini-Mental State Exam score of 27.4 (1.7). Comparisons using paired t-tests revealed improvements in the ADAS-cog (M difference: -2.7 (3.7), p <  0.001) and VO2max scores (M difference: 1.8 (2.0) mL/kg/min, p <  0.001). Brain metabolic analysis revealed a bilateral decrease in the rBGM of the dorsal anterior cingulate cortex, pFWE = 0.04. This rBGM decrease was negatively correlated with improvement in a visuospatial function/attentional test (rho =-0.31, p = 0.04). Several other brain areas also showed increases or decreases in rBGM. Of note, there was an increase in the retrosplenial cortex, an important node of the default mode network, that was negatively correlated with the metabolic decrease in the dorsal anterior cingulate cortex (r =-0.51, p = 0.001). CONCLUSION AT improved cognition and changed rBGM in areas related to cognition in subjects with MCI.

Aerobic training modulates salience network and default mode network metabolism in subjects with mild cognitive impairment

IntroductionMild cognitive impairment (MCI) is classically considered a transitional stage between normal aging and dementia. Non-amnestic MCI (naMCI) patients, however, typically demonstrate cognitive deficits other than memory decline. Furthermore, as a group, naMCI have a lower rate of an eventual dementia diagnosis as compared to amnestic subtypes of MCI (aMCI). Unfortunately, studies investigating biomarker profiles of naMCI are scarce. The study objective was to investigate the regional brain glucose metabolism (rBGM) with [18F]FDG-PET and cerebrospinal fluid (CSF) biomarkers in subjects with naMCI as compared to a control group (CG) and aMCI subjects.MethodsNinety-five patients were included in three different groups: naMCI (N = 32), aMCI (N = 33) and CG (N = 30). Patients underwent brain MRI and [18F]FDG-PET. A subsample (naMCI = 26, aMCI = 28) also had an assessment of amyloid-β, tau, and phosphorylated tau levels in the CSF.ResultsBoth MCI groups had lower rBGM in relation to the CG in the precuneus. Subjects with naMCI showed decreased right prefrontal metabolism as well as higher levels of CSF amyloid-β relative to aMCI subjects.ConclusionWhile amnestic MCI subjects showed a biomarker profile classically related to MCI due to Alzheimer’s disease, naMCI patients illustrated a decrease in both prefrontal hypometabolism and higher CSF amyloid-β levels relative to the aMCI group. These biomarker findings indicate that naMCI is probably a heterogeneous group with similar precuneus hypometabolism compared to aMCI, but additional frontal hypometabolism and less amyloid-β deposition in the brain. Clinical follow-up and reappraisal of biomarkers of the naMCI group is needed to determine the outcome and probable etiological diagnosis.

P-265Treatment choices in metastatic colorectal cancer according to sidedness and RAS/BRAF status: A national survey by the Brazilian Group of Gastrointestinal Tumors (GTG)

Lithium modulates several intracellular pathways related to neuroplasticity and resilience against neuronal injury. These properties have been consistently reported in experimental models, and involve the up-regulation of neurotrophic response and autophagy, and down-regulation of apoptosis, oxidative stress, and inflammation. Clinical and epidemiological studies in bipolar disorder show that acute treatment with lithium increases plasma concentrations of brain-derived neurotrophic factor, and long-term treatment lowers the risk of dementia. Neuroimaging studies indicate that lithium use is further associated with increased cortical thickness and larger hippocampal volumes. The objective of the present study was to evaluate whether these neurobiological properties of lithium reflect in increased regional brain glucose metabolism, as shown by [(18)F]FDG-PET. Participants (n = 19) were nondemented older adults recruited at the end point of a controlled trial addressing clinical and biological effects of lithium in a sample of patients with amnestic mild cognitive impairment. Twelve patients who had received low-dose lithium carbonate for 4 years were compared to seven matched controls. Chronic lithium treatment was not associated with any significant increase in brain glucose metabolism in the studied areas. Conversely, we found a significant reduction in glucose uptake in several clusters of the cerebellum and in both hippocampi. These findings were not associated with any clinical evidence of toxicity. The clinical implications of the present findings need to be clarified by future controlled studies, particularly in the light of the potential use of lithium as a disease-modifying treatment approach for certain neurodegenerative disorders, namely, Alzheimers disease and amyotrophic lateral sclerosis.

THE IMPACT OF COGNITIVE TRAINING ON BRAIN ACTIVITY AND CONNECTIVITY IN AMYLOID POSITIVE AND NEGATIVE 11C-PIB PET MCI AND HEALTHY ELDERLY INDIVIDUALS USING FMRI

Abstract Aside from cortical damage associated with age, cerebrovascular and neurodegenerative diseases, its an outstanding question if factors of global health, including normal variation in blood markers of metabolic and systemic function, may also be associated with individual variation in brain structure. This cross‐sectional study included 138 individuals between 40 to 86 years old who were physically healthy and cognitively intact. Eleven markers (total cholesterol, HDL, LDL, triglycerides, insulin, fasting glucose, glycated hemoglobin, creatinine, blood urea nitrogen, albumin, total protein) and five derived indicators (estimated glomerular filtration rate, creatinine clearance rate, insulin‐resistance, average glucose, and cholesterol/HDL ratio) were obtained from blood sampling of all participants. T1‐weighted 3T MRI scans were used to evaluate gray matter cortical thickness. The markers were clustered into five factors, and factor scores were related to cortical thickness by general linear model. Two factors, one linked to insulin/metabolic health and the other to kidney function (KFF) showed regionally selective associations with cortical thickness including lateral and medial temporal, temporoparietal, and superior parietal regions for both factors and frontoparietal regions for KFF. An association between the increasing cholesterol and greater thickness in frontoparietal and occipital areas was also noted. Associations persisted independently of age, presence of cardiovascular risk factors and ApoE gene status. These findings may provide information on distinct mechanisms of inter‐individual cortical variation as well as factors contributing to trajectories of cortical thinning with advancing age. HighlightsCortical thickness was associated with blood markers in younger and older adults.Associations were present even within the “normal range” of blood markers.Lower cortical thickness was associated with higher levels of insulin and lipids.Lower regional cortical thickness was associated with decreasing kidney function.Higher levels of cholesterol were associated with higher cortical thickness.