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Increasing evidence suggests that red and processed meat consumption may elevate the risk of colorectal cancer (CRC), yet the magnitude and consistency of this association remain debated. This meta-analysis aims to quantify the relationship between red and processed meat intake and the risk of CRC, colon cancer, and rectal cancer using the most comprehensive set of prospective studies to date. We conducted a comprehensive search in PubMed, Web of Science, Cochrane Library, Embase, and Google Scholar databases from 1990 to November 2024, to identify relevant prospective studies examining red, processed, and total meat consumption in relation to colorectal, colon, and rectal cancer risk. Hazard ratios (HR) and 95% confidence intervals (CI) were extracted for each study and pooled using a random-effects model to account for variability among studies. Statistical evaluation was executed using the online platform MetaAnalysisOnline.com. A total of 60 prospective studies were included. Red meat consumption was associated with a significantly increased risk of colon cancer (HR = 1.22, 95% CI 1.15–1.30), colorectal cancer (HR = 1.15, 95% CI 1.10–1.21), and rectal cancer (HR = 1.22, 95% CI 1.07–1.39). Processed meat consumption showed similar associations with increased risk for colon cancer (HR = 1.13, 95% CI 1.07–1.20), colorectal cancer (HR = 1.21, 95% CI 1.14–1.28), and rectal cancer (HR = 1.17, 95% CI 1.05–1.30). Total meat consumption also correlated with an elevated risk of colon cancer (HR = 1.22, 95% CI 1.11–1.35), colorectal cancer (HR = 1.17, 95% CI 1.12–1.22), and rectal cancer (HR = 1.28, 95% CI 1.10–1.48). This meta-analysis provides robust evidence that high consumption of red and processed meats is significantly associated with an increased risk of colorectal, colon, and rectal cancers. These findings reinforce current dietary recommendations advocating for the limitation of red and processed meat intake as part of cancer prevention strategies.

Cognitive decline has been postulated to predispose to presbyphagia but the neurophysiological basis of this interaction is unclear. To investigate the role of cognition for compensatory resource allocation within the swallowing network and behavioral swallowing performance in dual-task cognitive and motor interference in ageing, volunteers ≥ 70 years of age without preexisting diseases causing dysphagia were investigated using Flexible Endoscopic Evaluation of Swallowing (FEES) including a cognitive and motor dual-task paradigm and a Montreal Cognitive Assessment. The neural correlates of swallowing during dual-task were characterized using magnetoencephalography. Results were related to cognitive function. Sixty-three participants (77.7 ± 6.1 years) underwent FEES, of which 40 additionally underwent MEG. Both cognitive and motor dual-tasks interfered with swallowing function resulting in an increase in pharyngeal residue and premature bolus spillage. The extent of swallowing deterioration (“dual-task cost”) was associated with cognitive decline (cognitive dual-task: Spearman’s rho = − 0.39, p = 0.002; motor dual-task: Spearman’s rho = − 0.25, p = 0.046). When challenged with dual-tasking participants with regular cognition showed compensatory stronger and broader brain activation in cortical pre- and supplementary motor planning areas as well as in frontal executive regions within the cortical swallowing network (p = 0.004) compared to participants with cognitive deficits. They also performed better in the competing cognitive and motor dual-task and showed fewer incorrect responses (p = 0.028). Oropharyngeal swallowing involves cognitive cortical processing. Cognitive decline seems to limit the capacity for compensatory resource allocation within the swallowing network. This may lead to deterioration in both swallowing function and concurrent cognitive-motor performance in challenging dual-task situations.

Neuroimaging studies have shown age-related alterations in brain structure and function supporting semantic knowledge, although the significance of these is not fully understood. Herein, we report novel temporal, spectral, and spatial information on age-related changes from the largest dynamic functional mapping study of semantic processing. Participants (N = 130, age range 21–87 years, M_age = 51.05, SD = 14.73, 68 females) performed a semantic judgement task during magnetoencephalography (MEG), and significant task-related oscillatory responses were projected into anatomical space using a beamformer. Voxel-wise linear mixed-effects models were performed to assess semantic-related neural oscillations, irrespective of and influenced by age. Mediation analyses were performed to assess if local oscillations mediated the relationship between age and reaction time. Whole-brain analyses revealed stronger left-lateralized alpha/beta oscillations in frontotemporal cortices during semantic trials and stronger right-lateralized alpha/beta responses in temporoparietal regions during length trials (all ps <.001). Older adults showed stronger left temporoparietal alpha and left frontal beta during semantic processing and stronger alpha in the right temporal cortex during the length condition (all ps <.001). Alpha oscillations further mediated the relationship between age and reaction time in a hemisphere- and condition-specific manner, whereby right temporal activity mediated the age-behavior relationship in the length but not semantic condition (Z = 2.01, p =.022), while left temporoparietal activity significantly mediated this relationship in the semantic but not length condition (Z = − 2.41, p =.008). Altogether, our findings demonstrate accentuated oscillations in aging which are hemisphere- and condition-specific and support compensatory processing to aid in maintaining adequate behavioral performance, lending clear support to leading neuroscientific models of aging.

Peripheral arterial disease (PAD) is more prevalent in individuals with type 2 diabetes mellitus (T2DM). The most severe complication of PAD is chronic limb-threatening ischemia (CLTI), which is associated with major adverse cardiovascular events (MACE) and major adverse limb events (MALE) following lower limb revascularization (LER). This study investigates the relationship between baseline levels of Klotho and FGF23 and the risk of cardiovascular and limb-related outcomes after LER in a selected cohort of older adults. The study enrolled 109 older patients with PAD and CLTI requiring LER. Baseline levels of Klotho and FGF23 were measured, and their associations with subsequent MACE and MALE were analyzed over a 12-month follow-up period. Using stepwise multivariable logistic regression and Cox proportional hazards models, we found that among 109 older patients with PAD and CLTI undergoing LER, independent predictors of MACE included age (p = 0.016), male sex (p = 0.006), BMI (p = 0.004), diabetes duration (p = 0.031), hypertension (p = 0.013), and smoking status (p < 0.001), with higher FGF23 (p < 0.001) and lower Klotho levels (p = 0.002) significantly associated with increased risk; in the Cox model, increased Klotho was linked to a reduced risk of MACE (95% CI: 0.994–1.000, p = 0.022), while multivariate analysis for MALE confirmed Klotho as an independent predictor (p < 0.01). These findings reinforce the hypothesis that altered baseline levels of Klotho, and FGF23 are associated with adverse cardiovascular and limb outcomes in diabetic individuals over 75 years old with PAD and CLTI, highlighting their potential role as biomarkers for post-revascularization risk stratification.

Sleep disturbances are prevalent among elderly populations and are linked to various health complications. Understanding the underlying biological mechanisms contributing to sleep disorders is crucial for developing targeted interventions. In this study, we measured 355 plasma proteins in an elderly Japanese cohort (n=77) using a high-throughput proteomic platform. Additionally, we collected over 25,000 person-days of physical activity and sleep behavior data from wrist-worn wearable devices, focusing on total sleep time (TST) across 24 h and daytime sleep. Fragmented sleep was observed as one of the most prevalent sleep disturbances in this population. In protein expression analysis, we identified 9 protein biomarkers associated with increased secondary sleep TST, defined as additional sleep episodes outside of the main sleep episode within 24 h. These findings may suggest disruptions in circadian rhythms or underlying health conditions. Functional analysis revealed that biological processes related to inflammation play a significant role in regulating sleep behavior. Further analysis showed an association of 12 proteins with daytime sleep and 5 proteins with afternoon sleep. Overall, this study identified inflammatory biomarkers and biological processes associated with sleep behavior in the elderly, presenting promising opportunities for developing diagnostic tools and targeted clinical interventions.

Predicting Alzheimer’s disease (AD) pathology prior to clinical diagnosis is important for identifying individuals at high risk of developing AD dementia. However, there remains a gap in leveraging MRI and clinical data to predict AD pathology. This study examines a novel machine learning approach that integrates the combined vascular (white matter hyperintensities, WMHs) and structural brain changes (gray matter, GM) with clinical factors (cognitive scores) to predict post-mortem neuropathology. Participants from the Alzheimer's Disease Neuroimaging Initiative dataset (ADNI) and National Alzheimer's Coordinating Center (NACC) with both post-mortem neuropathology data and antemortem MRI and clinical data were included. Machine learning models were applied towards feature selection of the top seven MRI, clinical, and demographic data to identify the best performing set of variables that could predict postmortem neuropathology outcomes (i.e., neurofibrillary tangles, neuritic plaques, diffuse plaques, senile/amyloid plaques, and amyloid angiopathy). The best-performing neuropathology predictors from ADNI were then validated in NACC to compare results and ensure that the feature selection process did not lead to overfitting. In ADNI, the best-performing model included total and temporal lobe WMHs and achieved r = 0.87(RMSE = 0.62) during cross-validation for neuritic plaques. Overall, post-mortem neuropathology outcomes were predicted up to 14 years before death with high accuracies (~ 90%). Similar results were observed in the NACC dataset. These findings highlight that MRI features are critical to successfully predict AD-related pathology years in advance.

Aging is associated with a progressive decline in circulating insulin-like growth factor- 1 (IGF- 1) levels in humans, which has been implicated in the pathogenesis of sarcopenia. IGF- 1 is an anabolic hormone that plays a dual role in maintaining skeletal muscle health, acting both directly on muscle fibers to promote growth and indirectly by supporting the vascular network that sustains muscle perfusion. However, the microvascular consequences of IGF- 1 deficiency in aging muscle remain poorly understood. To elucidate how impaired IGF- 1 input affects skeletal muscle vasculature, we examined the effects of endothelial-specific IGF- 1 receptor (IGF- 1R) deficiency using a mouse model of endothelial IGF- 1R knockdown (VE-Cadherin-CreER^T2/Igf1r^f/f mice). These mice exhibited significantly reduced skeletal muscle endurance and attenuated hyperemic response to acetylcholine, an endothelium-dependent vasodilator. Additionally, they displayed microvascular rarefaction and impaired nitric oxide-dependent vasorelaxation, indicating a significant decline in microvascular health in skeletal muscle. These findings suggest that endothelial IGF- 1R signaling is critical for maintaining microvascular integrity, muscle perfusion, and function. Impaired IGF- 1 input to the microvascular endothelium may contribute to reduced muscle blood flow and exacerbate age-related sarcopenia. Enhancing vascular health by modulating IGF- 1 signaling could represent a potential therapeutic strategy to counteract age-related muscle decline.

With aging, the hippocampal formation shows variable structural atrophy, which is associated with a decline in cognitive performance. Bilingualism is related to higher hippocampal gray matter volume (GMV), potentially representing a form of brain reserve in aging. However, the differential influence of bilingualism on hippocampal subregions remains unclear. Thus, we investigated GMV differences and differences in age-GMV relationships between mono- and bilinguals in the hippocampal formation and its subregions, hippocampus proper and subicular complex. We included 661 adults aged 19 to 85 years (257 monolinguals, 404 sequential bilinguals, predominantly native German speakers with variable second language background) from the population-based 1000BRAINS cohort. GMV differences in mono- vs. bilinguals were assessed for six regions of interest (hippocampal formation, hippocampus proper, and subicular complex; each left and right) using analyses of covariance. Effects of bilingualism on age-GMV relationships were investigated via moderation analyses. We found higher GMV in bilinguals in the bilateral subicular complex, while only a trend towards this effect existed for the hippocampal formation. Moderation analyses revealed similar age-GMV relationships between mono- and bilinguals for all regions of interest. Higher GMV in bilinguals’ hippocampal formation seems specifically attributable to the subicular complex rather than the hippocampus proper. With similar age-GMV relationships for mono- and bilinguals, bilingual brain reserve in the subicular complex may persist over time. This may be particularly beneficial since subicular atrophy has previously been associated with higher risk for dementia. Altogether, a differential impact of bilingualism on hippocampal subregions has been demonstrated.

Delaying the initiation of cancer treatment increases the risk of mortality, particularly in colorectal cancer (CRC), which is among the most common and deadliest malignancies. This study aims to explore the impact of treatment delays on mortality in CRC. A systematic literature search was conducted in PubMed, Web of Science, and Scopus for studies published between 2000 and 2025. Meta-analyses were performed using random-effects models with inverse variance method to calculate hazard ratios (HRs) for both overall and cancer-specific survival at 4-, 8-, and 12-week treatment delay intervals, with heterogeneity assessed through I²-statistics and publication bias evaluated using funnel plots and Egger’s test. A total of 20 relevant studies were included in the meta-analysis. The analyses of all patients demonstrated a progressively increasing risk of 12–39% with longer treatment delays (4 weeks, HR = 1.12; 95% CI, 1.08–1.16; 8 weeks, HR = 1.24; 95% CI, 1.16–1.34; 12 weeks, HR = 1.39; 95% CI, 1.25–1.55). In particular, incrementally higher hazard ratios were observed for all–cause mortality at 4 weeks (HR = 1.14; 95% CI, 1.09–1.18), 8 weeks (HR = 1.29; 95% CI, 1.20–1.39), and 12 weeks (HR = 1.47; 95% CI, 1.31–1.64). In contrast, cancer-specific survival analysis showed a similar trend but did not reach statistical significance (4 weeks, HR = 1.07; 95% CI, 0.98–1.18; 8 weeks, HR = 1.15; 95% CI, 0.95–1.39; 12 weeks, HR = 1.23; 95% CI, 0.93–1.63). Treatment delays in colorectal cancer patients were associated with progressively worsening overall survival, with each 4-week delay increment leading to a substantially higher mortality risk. This study suggests that timely treatment initiation should be prioritized in clinical practice, as these efforts can lead to substantial improvements in survival rates.

Gut microbiota plays a significant role in nutrient extraction, metabolism, and immune function. Thus, the growing number of microbiome studies seek to link the presence and prevalence of specific bacteria, fungi, and viruses with a variety of physiological and disease outcomes. However, recruiting a diverse group of patients has been a challenge. Poor hearing and vision, lack of transportation, cognitive impairment, and a non-English primary language may interfere with patient enrollment as well as adherence to the requirements of a Microbiome study. Much of what we do know about diseases in older adults comes from studies that exclude many of these patients commonly encountered in clinical practice. The purpose of this review article is to highlight recruitment and retention strategies for engaging people who typically do not participate in microbiome studies, and it seeks to develop and explicate inclusion and exclusion criteria to promote more robust study results.