Serum klotho concentrations in older men with hypertension or type 2 diabetes during prolonged exercise in temperate and hot conditions

Unveiling the Prognostic Power of HRR in ICU-Admitted COPD Patients: A MIMIC-IV Database Study

Objective

This study sought to examine the potential relationship between Hemoglobin/Red Cell Distribution Width Ratio (HRR) and the all-cause mortality risk in critically ill patients with chronic obstructive pulmonary disease (COPD).

Patients and Methods

In a retrospective analysis of the MIMIC-IV database, patients were divided into two groups based on a specific HRR threshold. Propensity score matching (PSM) was employed to address covariate imbalances. Logistic regression models was used to examine the association between HRR and mortality. A restricted cubic spline (RCS) model was employed to visualize the association between HRR and mortality. Receiver Operating Characteristic (ROC) curves were utilized to assess the predictive capability of HRR, and Decision Curve Analysis (DCA) was conducted for clinical evaluation. Furthermore, subgroup analyses were performed to explore potential variations within specific cohorts.

Results

A comprehensive analysis identified a total of 1,061 patients. The threshold value established for HRR is 5.395 g/L/%. Following the application of PSM, the matched cohort comprised 544 patients. Both the original and matched cohorts exhibited higher rates of all-cause mortality and extended hospital stays among individuals with low HRRs. Logistic regression analyses demonstrated that HRR is an independent risk factor of mortality. The RCS analysis demonstrated a significant linear relationship between HRR and mortality. The ROC curves yielded values of 0.58 for the original cohort and 0.60 for the matched cohort. DCA analysis indicated that HRR is clinically valuable. Subgroup analyses further validated the robustness of these core findings.

Conclusion

A lower HRR is positively associated with all-cause mortality in critically ill patients with COPD.

Experimental research in environmentally induced hyperthermic older persons: A systematic quantitative literature review mapping the available evidence

The heat-related health burden is expected to persist and worsen in the coming years due to an aging global population and climate change. Defining the breadth and depth of our understanding of age-related changes in thermoregulation can identify underlying causes and strategies to protect vulnerable individuals from heat. We conducted the first systematic quantitative literature review to provide context to the historical experimental research of healthy older adults - compared to younger adults or unhealthy age matched cases - during exogenous heat strain, focusing on factors that influence thermoregulatory function (e.g. co-morbidities). We identified 4,455 articles, with 147 meeting eligibility criteria. Most studies were conducted in the US (39%), Canada (29%), or Japan (12%), with 71% of the 3,411 participants being male. About 71% of the studies compared younger and older adults, while 34% compared two groups of older adults with and without factors influencing thermoregulation. Key factors included age combined with another factor (23%), underlying biological mechanisms (18%), age independently (15%), influencing health conditions (15%), adaptation potential (12%), environmental conditions (9%), and therapeutic/pharmacological interventions (7%). Our results suggest that controlled experimental research should focus on the age-related changes in thermoregulation in the very old, females, those with overlooked chronic heat-sensitive health conditions (e.g. pulmonary, renal, mental disorders), the impact of multimorbidity, prolonged and cumulative effects of extreme heat, evidence-based policy of control measures (e.g. personal cooling strategies), pharmaceutical interactions, and interventions stimulating protective physiological adaptation. These controlled studies will inform the directions and use of limited resources in ecologically valid fieldwork studies.

Klotho Gene Expression Is Decreased in Peripheral Blood Mononuclear Cells in Patients with Alzheimer's Disease and Frontotemporal Dementia

BACKGROUND

The longevity gene Klotho (KL) was recently associated with neurodegenerative diseases including Alzheimer's disease (AD). Its role in the brain has not been completely elucidated, although evidence suggests that KL-VS heterozygosity is associated with a reduced risk of AD in Apolipoprotein E ɛ4 carriers. Conversely, no data about genetic association with frontotemporal dementia (FTD) are available so far.

OBJECTIVE

To investigate the involvement of KL in AD and FTD by the determination of the genetic frequency of KL-VS variant and the expression analysis of KL gene.

METHODS

A population consisting of 438 patients and 240 age-matched controls was enrolled for the study. KL-VS and APOE genotypes were assessed by allelic discrimination through a QuantStudio 12K system. KL gene expression analysis was performed in a restricted cohort of patients consisting of 43 AD patients, 41 FTD patients and 19 controls. KL gene expression was assessed in peripheral blood mononuclear cells with specific TaqMan assay. Statistical analysis was performed using GraphPad 9 Prims software.

RESULTS

KL-VS frequency was comparable to the ones found in literature and no differences were found in both allelic and genotypic frequencies between patients and controls were found. Conversely, KL expression levels were significantly lower in AD and FTD patients compared with controls (mean fold regulation - 4.286 and - 6.561 versus controls in AD and FTD, respectively, p = 0.0037).

CONCLUSION

This is the first study investigating KL in FTD. We showed a decreased expression of the gene in AD and FTD, independent of the genotype, suggesting a role of Klotho in common steps during neurodegeneration.