61 research outputs found
Surgical versus balloon therapy for aortic coarctation in infants ≤ 3 months old
AbstractObjectives. This study compared the efficacy and safety of balloon angioplasty with surgical correction of native aortic coarctation in infants ≤3 months old.Background. There is a controversy with regard to the role of balloon angioplasty in the treatment of aortic coarctation, especially in young infants.Methods. Data from 29 infants ≤3 months old undergoing therapy for aortic coarctation during the decade ending 1992 were analyzed. Fourteen infants underwent surgery, and 15 had balloon angioplasty. The sole criterion for allotment to the balloon group was the availability of an interventional cardiologist at the time of presentation of the infant.Results. The surgical and balloon groups were comparable (p > 0.1) with regard to age (27 ± 35 [mean ± SD] vs. 29 ± 27 days), weight (3.5 ± 0.9 vs. 3.8 ± 1.0 kg) and prevalence (7 of 14 vs. 8 of 15) and type of associated defects. Operative (1 of 14 vs. 1 of 15) and late (3 of 13 vs. 3 of 14) mortality, immediate gradient relief (36 ± 25 to 10 ± 9 mm Hg vs. 41 ± 14 to 6 ± 6 mm Hg) and follow-up gradient (27 ± 27 vs. 24 ± 19 mm Hg) were similar (p > 0.1). Infants with a gradient > 20 mm Hg at follow-up (6 of 13 vs. 7 of 14) and need for reintervention (6 of 13 vs. 7 of 14) were also similar (p > 0.1) in both groups. Duration of hospital stay during the first intervention was higher (p < 0.05) in the surgical (32 ± 37 days) than the balloon (7 ± 6 days) group. Similarly, duration of endotracheal intubation and mechanical ventilation was longer (p < 0.05) in the surgical (12 ± 16 days) than the balloon (2 ± 3 days) group. Complications after surgical intervention (0.86 events/patient) were higher (p < 0.01) than those seen after balloon angioplasty (0.27 events/patient). However, the lack of significant differences observed for mortality rates and residual gradients may be due to low statistical power to detect differences (16% to 49%), implying that this may be due to either actual lack of statistical difference or small sample size.Conclusions. The data indicate that the degree of relief from aortic coarctation and the frequency with which reintervention is needed are similar in both groups. However, the morbidity and complication rates are lower with balloon than with surgical therapy. These data suggest that balloon angioplasty may be an acceptable alternative to surgical correction in the treatment of symptomatic aortic coarctation in infants ≤3 months old
Structural MRI discriminates individuals with Mild Cognitive Impairment from age-matched controls: A combined neuropsychological and voxel based morphometry study
Background: Several previous studies have reported that amnestic mild cognitive impairment (aMCI), a significant risk factor for Alzheimer\u27s disease (AD), is associated with greater atrophy in the medial temporal lobe (MTL) and posterior cingulate gyrus (PCG). Method: In the present study, we examined the cross-sectional accuracy (i.e., the sensitivity and specificity) of voxel-based morphometry (VBM) in discriminating individuals with MCI (n = 15) from healthy age-matched controls (n = 15). In addition, we also sought to determine whether baseline GM volume predicted aMCI patients that converted to AD from those that did not approximately 2 years after the baseline visit. Results: MCI patients were found to display significantly less GM volume in several hypothesized regions including the MTL and PCG relative to the age-matched controls (p \u3c 0.01). Logistic regression analysis and receiver operating characteristic (ROC) curves for GM volume in the anterior MTL and PCG revealed high discriminative accuracy of 87%. By contrast, baseline GM volume in anterior MTL and PCG did not appear to be sensitive to changes in clinical status at the follow-up visit. Conclusion: These results suggest that VBM might be useful at characterizing GM volume reductions associated with the diagnosis of aMCI. © 2006 The Alzheimer\u27s Association
Cross-sectional associations of CSF tau levels with Rey's AVLT: A recency ratio study
OBJECTIVE: The preeminent in vivo cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) are amyloid β 1-42 (Aβ42), phosphorylated Tau (p-tau), and total Tau (t-tau). The goal of this study was to examine how well traditional (total and delayed recall) and process-based (recency ratio [Rr]) measures derived from Rey's Auditory Verbal Learning test (AVLT) were associated with these biomarkers. METHOD: Data from 235 participants (Mage = 65.5, SD = 6.9), who ranged from cognitively unimpaired to mild cognitive impairment, and for whom CSF values were available, were extracted from the Wisconsin Registry for Alzheimer's Prevention. Bayesian regression analyses were carried out using CSF scores as outcomes, AVLT scores as predictors, and controlling for demographic data and diagnosis. RESULTS: We found moderate evidence that Rr was associated with both CSF p-tau (Bayesian factor [BFM] = 5.55) and t-tau (BFM = 7.28), above and beyond the control variables, while it did not correlate with CSF Aβ42 levels. In contrast, total and delayed recall scores were not linked with any of the AD biomarkers, in separate analyses. When comparing all memory predictors in a single regression, Rr remained the strongest predictor of CSF t-tau levels (BFM = 3.57). CONCLUSIONS: Our findings suggest that Rr may be a better cognitive measure than commonly used AVLT scores to assess CSF levels of p-tau and t-tau in nondemented individuals. (PsycInfo Database Record (c) 2022 APA, all rights reserved)
Item-level story recall predictors of amyloid-beta in late middle-aged adults at increased risk for Alzheimer’s disease
Background: Story recall (SR) tests have shown sensitivity to rate of cognitive decline in individuals with Alzheimer’s disease (AD) biomarkers. Although SR tasks are typically scored by obtaining a sum of items recalled, item-level analyses may provide additional sensitivity to change and AD processes. Here we examined the difficulty and discrimination indices of each item from the Logical Memory (LM) SR task, and determined if these metrics differed by recall conditions, story version (A vs. B), lexical categories, serial position, and amyloid status. Methods: n=1141 participants from the Wisconsin Registry for Alzheimer’s Prevention longitudinal study who had item-level data were included in these analyses, as well as a subset of n=338 who also had amyloid PET imaging. LM data were categorized into 4 lexical categories (proper names, verbs, numbers, and ‘other’), and by serial position (primacy, middle, and recency). We calculated difficulty and discriminability/memorability by item, category, and serial position and ran separate repeated measures ANOVAs for each recall condition, lexical category, and serial position. For the subset with amyloid imaging, we used a two-sample t-test to examine whether amyloid positive (A+) and amyloid negative (A-) groups differed in difficulty or discrimination for the same summary metrics. In review Results: In the larger sample, items were more difficult (less memorable) in the delayed recall condition across both story A and story B. Item discrimination was higher at delayed than immediate recall, and proper names had better discrimination than any of the other lexical categories or serial position groups. In the subsample with amyloid PET imaging, proper names were more difficult for A+ than A-; items in the verb and ‘other’ lexical categories and all serial positions from delayed recall were more discriminate for the A+ group compared to the A- group. Conclusion: This study provides empirical evidence that both LM stories are effective at discriminating ability levels and amyloid status, and that individual items vary in difficulty and discrimination by amyloid status, while total scores do not. These results can be informative for the future development of sensitive tasks or composite scores for early detection of cognitive decline
Effect of Pathway-Specific Polygenic Risk Scores for Alzheimer's Disease (AD) on Rate of Change in Cognitive Function and AD-Related Biomarkers Among Asymptomatic Individuals
BACKGROUND: Genetic scores for late-onset Alzheimer's disease (LOAD) have been associated with preclinical cognitive decline and biomarker variations. Compared with an overall polygenic risk score (PRS), a pathway-specific PRS (p-PRS) may be more appropriate in predicting a specific biomarker or cognitive component underlying LOAD pathology earlier in the lifespan. OBJECTIVE: In this study, we leveraged longitudinal data from the Wisconsin Registry for Alzheimer's Prevention and explored changing patterns in cognition and biomarkers at various age points along six biological pathways. METHODS: PRS and p-PRSs with and without APOE were constructed separately based on the significant SNPs associated with LOAD in a recent genome-wide association study meta-analysis and compared to APOE alone. We used a linear mixed-effects model to assess the association between PRS/p-PRSs and cognitive trajectories among 1,175 individuals. We also applied the model to the outcomes of cerebrospinal fluid biomarkers in a subset. Replication analyses were performed in an independent sample. RESULTS: We found p-PRSs and the overall PRS can predict preclinical changes in cognition and biomarkers. The effects of PRS/p-PRSs on rate of change in cognition, amyloid-β, and tau outcomes are dependent on age and appear earlier in the lifespan when APOE is included in these risk scores compared to when APOE is excluded. CONCLUSION: In addition to APOE, the p-PRSs can predict age-dependent changes in amyloid-β, tau, and cognition. Once validated, they could be used to identify individuals with an elevated genetic risk of accumulating amyloid-β and tau, long before the onset of clinical symptoms
Associations Between Performance on an Abbreviated CogState Battery, Other Measures of Cognitive Function, and Biomarkers in People at Risk for Alzheimer\u27s Disease
It is not known whether computerized cognitive assessments, like the CogState battery, are sensitive to preclinical cognitive changes or pathology in people at risk for Alzheimer\u27s disease(AD). In 469 late middle-aged participants from the Wisconsin Registry for Alzheimer\u27s Prevention(mean age 63.8±7 years at testing; 67% female; 39% APOE4+), we examined relationships between a CogState abbreviated battery(CAB) of seven tests and demographic characteristics, traditional paper-based neuropsychological tests as well as a composite cognitive impairment index, cognitive impairment status(determined by consensus review), and biomarkers for amyloid and tau(CSF phosphorylated-tau/Aβ42 and global PET-PiB burden) and neural injury(CSF neurofilament light protein). CSF and PET-PiB were collected in n = 71 and n = 91 participants, respectively, approximately four years prior to CAB testing. For comparison, we examined three traditional tests of delayed memory in parallel. Similar to studies in older samples, the CAB was less influenced by demographic factors than traditional tests. CAB tests were generally correlated with most paper-based cognitive tests examined and mapped onto the same cognitive domains. Greater composite cognitive impairment index was associated with worse performance on all CAB tests. Cognitively impaired participants performed significantly worse compared to normal controls on all but one CAB test. Poorer One Card Learning test performance was associated with higher levels of CSF phosphorylated-tau/Aβ42. These results support the use of the CogState battery as measures of early cognitive impairment in studies of people at risk for AD
Crosswalk study on blood collection-tube types for Alzheimer's disease biomarkers
Introduction: Blood-based Alzheimer's disease (AD) biomarkers show promise, but pre-analytical protocol differences may pose problems. We examined seven AD blood biomarkers (amyloid beta [ A β ] 42 , A β 40 , phosphorylated tau [ p - ta u 181 , total tau [t-tau], neurofilament light chain [NfL], A β 42 40 , and p - ta u 181 A β 42 ) in three collection tube types (ethylenediaminetetraacetic acid [EDTA] plasma, heparin plasma, serum). Methods: Plasma and serum were obtained from cerebrospinal fluid or amyloid positron emission tomography-positive and -negative participants (N = 38) in the Wisconsin Registry for Alzheimer's Prevention. We modeled AD biomarker values observed in EDTA plasma versus heparin plasma and serum, and assessed correspondence with brain amyloidosis. Results: Results suggested bias due to tube type, but crosswalks are possible for some analytes, with excellent model fit for NfL ( R 2 = 0.94), adequate for amyloid ( R 2 = 0.40-0.69), and weaker for t-tau ( R 2 = 0.04-0.42) and p - ta u 181 ( R 2 = 0.22-0.29). Brain amyloidosis differentiated several measures, especially EDTA plasma pTa u 181 A β 42 ( d = 1.29). Discussion: AD biomarker concentrations vary by tube type. However, correlations for some biomarkers support harmonization across types, suggesting cautious optimism for use in banked blood
Relationships between cardiorespiratory fitness, hippocampal volume, and episodic memory in a population at risk for Alzheimer’s disease
Introduction: Cardiorespiratory fitness (CRF) has been shown to be related to brain health in older adults. In individuals at risk for developing Alzheimer\u27s disease (AD), CRF may be a modifiable risk factor that could attenuate anticipated declines in brain volume and episodic memory. The objective of this study was to determine the association between CRF and both hippocampal volume and episodic memory in a cohort of cognitively healthy older adults with familial and/or genetic risk for Alzheimer\u27s disease (AD).
Methods: Eighty‐six enrollees from the Wisconsin Registry for Alzheimer\u27s Prevention participated in this study. Participants performed a graded maximal exercise test, underwent a T‐1 anatomical magnetic resonance imaging scan, and completed the Rey Auditory Verbal Learning Test (RAVLT).
Results: There were no significant relationships between CRF and HV or RAVLT memory scores for the entire sample. When the sample was explored on the basis of gender, CRF was significantly associated with hippocampal volume for women. For men, significant positive associations were observed between CRF and RAVLT memory scores.
Summary: These results suggest that CRF may be protective against both hippocampal volume and episodic memory decline in older adults at risk for AD, but that the relationships may be gender specific
Positive Affect Predicts Cerebral Glucose Metabolism in Late Middle-aged Adults.
Positive affect is associated with a number of health benefits; however, few studies have examined the relationship between positive affect and cerebral glucose metabolism, a key energy source for neuronal function and a possible index of brain health. We sought to determine if positive affect was associated with cerebral glucose metabolism in late middle-aged adults (n = 133). Participants completed the positive affect subscale of the Center for Epidemiological Studies Depression Scale at two time points over a two-year period and underwent 18F-fluorodeoxyglucose-positron emission tomography scanning. After controlling for age, sex, perceived health status, depressive symptoms, anti-depressant use, family history of Alzheimer’s disease, APOE ε4 status and interval between visits, positive affect was associated with greater cerebral glucose metabolism across para-/limbic, frontal, temporal and parietal regions. Our findings provide evidence that positive affect in late midlife is associated with greater brain health in regions involved in affective processing and also known to be susceptible to early neuropathological processes. The current findings may have implications for interventions aimed at increasing positive affect to attenuate early neuropathological changes in at-risk individuals
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