Longitudinal trajectories in cortical thickness and volume atrophy: Superior cognitive performance does not protect against brain atrophy in older adults

Background: Previous research has identified a small subgroup of older adults that maintain a high level of cognitive functioning well into advanced age. Investigation of those with superior cognitive performance (SCP) for their age is important, as age-related decline has previously been thought to be inevitable. Objective: Preservation of cortical thickness and volume was evaluated in 76 older adults with SCP and 100 typical older adults (TOAs) assessed up to five times over six years. Methods: Regions of interest (ROIs) found to have been associated with super-aging status (a construct similar to SCP status) in previous literature were investigated, followed by a discovery phase analyses of additional regions. SCPs were aged 70 + at baseline, scoring at/above normative memory (CVLT-II) levels for demographically similar individuals aged 30–44 years old, and in the unimpaired range for all other cognitive domains over the course of the study. Results: In linear mixed models, following adjustment for multiple comparisons, there were no significant differences between rates of thinning or volume atrophy between SCPs and TOAs in previously identified ROIs, or the discovery phase analyses. With only amyloid-β negative individuals in the analyses, again there were no significant differences between SCPs and TOAs. Conclusion: The increased methodological rigor in classifying groups, together with the influence of cognitive reserve, are discussed as potential factors accounting for our findings as compared to the extant literature on those with superior cognitive performance for their age

An open-label study to describe pharmacokinetic parameters of erlotinib in patients with advanced solid tumors with adequate and moderately impaired hepatic function

Purpose: To compare the pharmacokinetic (PK) parameters of a single dose of erlotinib in cancer patients with moderate hepatic impairment (MHI) to those of cancer patients with adequate hepatic function (AHF). <p/>Methods: Cancer patients with either AHF or MHI were treated with a single 150 mg dose of erlotinib on day 1 only followed by 96 h of plasma sampling for PK assessment. From day 5, patients were allowed to continue daily erlotinib in a maintenance phase. Non-smoking patients were stratified into an AHF cohort (total bilirubin ≤ upper limit of normal [ULN] and ALT/AST ≤ 1.5 X ULN) or a MHI cohort (Child-Pugh score of 7–9). The frequency of adverse events and laboratory changes were assessed. <p/>Results: Thirty-six patients, 21 with AHF and 15 with MHI, received at least one dose of erlotinib. The PK of erlotinib was similar between the two cohorts with a median C max of 1.09 versus 0.828 μg/mL and corresponding median AUC0−t 29.3 versus 30.5 μg h/mL for the AHF and MHI cohorts, respectively. Adverse events from erlotinib in cancer patients with MHI were consistent with the known safety profile. <p/>Conclusions: The PK and safety profiles of erlotinib in patients with MHI were similar to those with AHF. As a result, a reduced starting dose of erlotinib in patients with MHI is not required and treatment should be guided by patients’ tolerability

Increased Carbohydrate Intake is Associated with Poorer Performance in Verbal Memory and Attention in an APOE Genotype-Dependent Manner

Evidence suggests that a diet low in carbohydrates can impact on cognitive performance among those with Alzheimer's disease (AD). However, there is a lack of data assessing this relationship among cognitively normal (CN) older adults at increased future risk of developing AD due to carriage of the apolipoprotein E (APOE) ?4 allele. We assessed the cross-sectional association between carbohydrate intake, cognitive performance, and cerebral amyloid-ß (Aß) load in CN older adults, genotyped for APOE ?4 allele carrier status. Greater carbohydrate intake was associated with poorer performance in verbal memory in APOE ?4 allele non-carriers, and poorer performance in attention in APOE ?4 allele carriers. There were no associations between carbohydrate intake and cerebral Aß load. These results provide support to the idea that decreasing carbohydrate intake may offer neurocognitive benefits, with specific cognitive domains affected in an APOE genotype-dependent manner. These findings warrant further investigation utilizing a longitudinal study design

New insights into the genetic etiology of Alzheimer’s disease and related dementias

Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele. © 2022, The Author(s)