Genetically downregulated Interleukin-6 signalling is associated with a lower risk of frailty

Propensity Score Matching Analysis on Risk Factors and Their Diagnostic Value of Frailty in Elderly Patients With Cerebral Infarction

OBJECTIVES

Cerebral infarction is an acute ischemic cerebrovascular disease; elderly patients with cerebral infarction often have frailty syndrome. Therefore, the aim of this study was to analyze the risk factors and their diagnostic value of frailty in elderly patients with cerebral infarction.

METHODS

In this retrospective cohort study, the medical records (from October 2017 to September 2020) of patients with cerebral infarction (n=395) were analyzed. According to different frailty statuses, patients were divided into the health group (n=166) and the prefrailty group (n=229). The diagnostic value of various parameters for the occurrence of pre-frailty was assessed by the receiver operating characteristic (ROC) curve and area under the ROC curve (AUC). The risk factors were analyzed by single-factor and multi-factor analyses.

RESULTS

Interleukin-6 (IL-6, P<0.001), C-reactive protein (CRP), prealbumin (PA, P<0.001), albumin (ALB, P<0.001), and brain natriuretic peptide (BNP, P<0.001) had higher diagnostic value for the occurrence of prefrailty in elderly patients with cerebral infarction. Single-factor and multi-factor analysis results revealed that the length of stay (LOS), comorbidity with nervous system diseases, high Charlson comorbidity index (CCI), high National Institute of Health stroke scale score, IL-6, BNP, ALB, PA, and creatine kinase might risk the factors for prefrailty occurrence (P<0.05). After the elimination of interference factors, LOS, high CCI, IL-6, and ALB were confirmed to be key risk factors for the occurrence of prefrailty (P<0.05).

CONCLUSION

LOS, high CCI, IL-6, and ALB are the underlying risk factors for the occurrence of prefrailty in elderly patients with cerebral infarction, which provides a theoretical basis for clinical disease diagnosis.

Casual associations between frailty and nine mental disorders: bidirectional Mendelian randomisation study

BACKGROUND

An increasing number of observational studies have reported associations between frailty and mental disorders, but the causality remains ambiguous.

AIMS

To assess the bidirectional causal relationship between frailty and nine mental disorders.

METHOD

We conducted a bidirectional two-sample Mendelian randomisation on genome-wide association study summary data, to investigate causality between frailty and nine mental disorders. Causal effects were primarily estimated using inverse variance weighted method. Several secondary analyses were applied to verify the results. Cochran's Q-test and Mendelian randomisation Egger intercept were applied to evaluate heterogeneity and pleiotropy.

RESULTS

Genetically determined frailty was significantly associated with increased risk of major depressive disorder (MDD) (odds ratio 1.86, 95% CI 1.36-2.53, P = 8.1 × 10-5), anxiety (odds ratio 2.76, 95% CI 1.56-4.90, P = 5.0 × 10-4), post-traumatic stress disorder (PTSD) (odds ratio 2.56, 95% CI 1.69-3.87, P = 9.9 × 10-6), neuroticism (β = 0.25, 95% CI 0.11-0.38, P = 3.3 × 10-4) and insomnia (β = 0.50, 95% CI 0.25-0.75, P = 1.1 × 10-4). Conversely, genetic liability to MDD, neuroticism, insomnia and suicide attempt significantly increased risk of frailty (MDD: β = 0.071, 95% CI 0.033-0.110, P = 2.8 × 10-4; neuroticism: β = 0.269, 95% CI 0.173-0.365, P = 3.4 × 10-8; insomnia: β = 0.160, 95% CI 0.141-0.179, P = 3.2 × 10-61; suicide attempt: β = 0.056, 95% CI 0.029-0.084, P = 3.4 × 10-5). There was a suggestive detrimental association of frailty on suicide attempt and an inverse relationship of subjective well-being on frailty.

CONCLUSIONS

Our findings show bidirectional causal associations between frailty and MDD, insomnia and neuroticism. Additionally, higher frailty levels are associated with anxiety and PTSD, and suicide attempts are correlated with increased frailty. Understanding these associations is crucial for the effective management of frailty and improvement of mental disorders.

Frailty in Older Adults with Severe Aortic Stenosis: The Role of Systemic Inflammation and Calcium Homeostasis

Background: Frailty and severe aortic stenosis (AoS) are critical conditions in older adults, both of which share pathophysiological mechanisms including chronic inflammation and calcium metabolism dysregulation, potentially influencing the development and progression of these conditions. This study aimed to analyze systemic inflammation and calcium homeostasis biomarkers and their associations with frailty in older adults with severe AoS. Methods: This prospective study included 191 patients aged ≥75 years with severe AoS who were candidates for aortic valve replacement and were evaluated at a Geriatrics Frailty Assessment and Intervention Clinic. Frailty was defined as a score ≤6 on the Short Physical Performance Battery (SPPB). Biomarkers analyzed included aortic valve calcium score, parathyroid hormone (PTH), calcidiol (vitamin D), calcium, phosphate, creatinine, interleukin-6 (IL-6), and the Systemic Immune-Inflammation Index. Multivariate logistic regression was performed to identify independent predictors of frailty. Results: Of the 191 patients studied, 53.9% were women, with a mean age of 84.1 ± 4.1 years. Frailty was identified in 28.3% of patients (mean SPPB score 7.6 ± 2.5). Statistically significant differences between frail and non-frail patients were observed for PTH (87.7 ± 61.1 pg/mL vs. 70 ± 44.4 pg/mL, p = 0.028) and IL-6 (10.4 ± 11.2 pg/mL vs. 7 ± 8.2 pg/mL, p = 0.049). Notably, in the multivariate model, IL-6 emerged as a significant independent predictor of frailty (OR 1.037; CI 1.001-1.074, p = 0.043). Conclusions: IL-6 was identified as a biomarker significantly associated with frailty in older adults with severe AoS. Evaluating IL-6 could enhance the precision of frailty assessments, complement functional measures, and support clinical decision-making in this population.

Older Adults With Celiac Disease Are At Increased Risk of Frailty: A Nationwide Cohort Study

INTRODUCTION

Celiac disease (CeD) is increasingly diagnosed in older adults, though few studies have explored complications in this group. As frailty confers increased risk for adverse events, we aimed to explore frailty in older adults with CeD.

METHODS

In a nationwide Swedish cohort, we identified adults ≥60 years with incident CeD between 2004 and 2017 which we matched to population-based controls without CeD by age, sex, county, and calendar-period. Baseline frailty within 3 years before CeD diagnosis or index date was assessed using the Hospital Frailty Risk Score. Among those without baseline frailty, we used conditional logistic regression to estimate odds ratios and 95% confidence intervals of future frailty at 5 years comparing CeD with controls. Logistic regression was used to evaluate the association between persistent villous atrophy vs mucosal healing and frailty in patients with CeD.

RESULTS

A total of 4,646 older adults with CeD were matched to 21,944 non-CeD individuals. Baseline frailty was increased in patients with CeD (54.4%) compared with controls (29.7%, P < 0.001), which existed across all frailty categories: low-risk (43.4% vs 23.8%), intermediate-risk (10.3% vs 5.4%), and high-risk (0.8% vs 0.6%). Among those without baseline frailty, patients with CeD had a 61% increased risk of overall frailty at 5 years (95% confidence interval 1.46-1.78). Mucosal healing in CeD individuals on follow-up biopsy did not protect against future frailty.

DISCUSSION

Older adults with CeD were significantly more likely to become frail than matched comparators. This analysis reveals the increased vulnerability that older patients with CeD are likely to experience.

Gastroesophageal reflux disease influences blood pressure components, lipid profile and cardiovascular diseases: Evidence from a Mendelian randomization study

BACKGROUND

Gastroesophageal reflux disease (GERD) is a prevalent gastrointestinal disorder associated with a range of cardiovascular and metabolic complications. However, the relationship between GERD and blood pressure components, lipid profile, and cardiovascular diseases remains unclear.

METHODS

Leveraging genetic variants associated with GERD as instrumental variables, we performed this Mendelian randomization (MR) analyses. Blood pressure components, lipid profile parameters, as well as cardiovascular diseases were considered as outcomes. Furthermore, we conducted reverse MR analysis to explore the association of these factors with the risk of GERD.

RESULTS

Our MR analysis discovered a potential causal influence of GERD on blood pressure components, with genetically predicted GERD positively associated with systolic blood pressure (β = 0.053, P = 0.036), diastolic blood pressure (β = 0.100, P < 0.001), and mean arterial pressure (β = 0.106, P < 0.001). Additionally, genetically predicted GERD showed a significant impact on lipid profile, leading to increased genetically predicted levels of low-density lipoprotein (LDL) cholesterol (β = 0.093, P < 0.001), and triglycerides (β = 0.153, P < 0.001), while having a negative effect on high-density lipoprotein (HDL) cholesterol (β = -0.115, P = 0.002). Furthermore, our study indicated a noteworthy causal association between genetically predicted GERD and increased risk of myocardial infarction [odds ratio (OR) = 1.272, P = 0.019)] and hypertension (OR = 1.357, P < 0.001). No significant association was found between GERD and pulse pressure, total cholesterol, heart failure, and atrial fibrillation (P > 0.05). Reverse MR analysis indicates that blood pressure components, lipid profile, and cardiovascular diseases do not lead to an increased risk of GERD (all P > 0.05). Furthermore, mediation MR analysis reveals that LDL cholesterol (proportion mediated: 19.99%, 95% CI: 4.49% to 35.50%), HDL cholesterol (proportion mediated: 11.71%, 95% CI: 5.23% to 18.19%), and hypertension (proportion mediated: 35.09%, 95% CI: 24.66% to 45.53%) mediated the effect of GERD on myocardial infarction, while other factors did not participate in this pathway.

CONCLUSIONS

This MR study provides evidence supporting a causal relationship between GERD and alterations in blood pressure components, lipid profile, and increased risk of cardiovascular diseases.

Sex-specific relationships of inflammatory biomarkers with blood pressure in older adults

Emerging evidence indicates an association between blood pressure and inflammation, yet this relationship remains unclear in older adults, despite the elevated prevalence of hypertension. We investigated the association between blood pressure, high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and white blood cell (WBC) count in a cohort of 3571 older adults aged 65 and above, and 587 middle-aged participants (55-59 years old). In women aged 65 and above, the relationship between inflammatory markers and blood pressure was consistent, with hs-CRP and WBC emerging as predictors of high blood pressure. For hs-CRP, the adjusted odds ratio (OR) was 1.5 (95% CI, 1.07 to 2.10, P = 0.02), and for WBC, the adjusted OR was 1.41 (95% CI, 1.02 to 1.94, P = 0.04), comparing the highest to the lowest quartiles. In men, only the WBC count was significantly associated with an increased OR for high BP (adjusted OR 1.49, 95% CI, 1.09 to 2.02, P = 0.01) across quartiles. Across the entire study population, in a fully adjusted model, all inflammatory markers were modestly associated with blood pressure levels, while the effect of being over 65 years was the most significant predictor of high blood pressure (OR 1.84, 95% CI, 1.50 to 2.25, P < 0.001). The link between key inflammation markers and blood pressure in older adults varies by sex and biomarker type and may differ from the relationship observed in younger individuals. These relationships are likely to be affected by factors linked to age.

Interleukin-6 promotes visceral adipose tissue accumulation during aging via inhibiting fat lipolysis

BACKGROUND

Age-related visceral obesity could contribute to the development of cardiometabolic complications. The pathogenesis of visceral fat mass accumulation during the aging process remains complex and largely unknown. Interleukin-6 (IL-6) has emerged as one of the prominent inflammaging markers which are elevated in circulation during aging. However, the precise role of IL-6 in regulating age-related visceral adipose tissue accumulation remains uncertain.

RESULTS

A cross-sectional study including 77 older adults (≥65 years of age) was initially conducted. There was a significant positive association between serum IL-6 levels and visceral fat mass. We subsequently validated a modest but significant elevation in serum IL-6 levels in aged mice. Furthermore, we demonstrated that compared to wildtype control, IL-6 deficiency (IL-6 KO) significantly attenuated the accumulation of visceral adipose tissue during aging. Further metabolic characterization suggested that IL-6 deficiency resulted in improved lipid metabolism parameters and energy expenditure in aged mice. Moreover, histological examinations of adipose depots revealed that the absence of IL-6 ameliorated adipocyte hypertrophy in visceral adipose tissue of aged mice. Mechanically, the ablation of IL-6 could promote the PKA-mediated lipolysis and consequently mitigate lipid accumulation in adipose tissue in aged mice.

CONCLUSION

Our findings identify a detrimental role of IL-6 during the aging process by promoting visceral adipose tissue accumulation through inhibition of lipolysis. Therefore, strategies aimed at preventing or reducing IL-6 levels may potentially ameliorate age-related obesity and improve metabolism during aging.

Modifiable Lifestyle, Sedentary Behaviors and the Risk of Frailty: A Univariate and Multivariate Mendelian Randomization Study

This research conducted a two-sample univariate and multivariate Mendelian Randomization (MR) analysis to explore the causal link between different types of leisure sedentary behavior (LSB) and frailty. Independent instrumental variables significantly associated with sedentary behaviors (p < 5 × 10-8) are obtained from a genome-wide association study (GWAS) of 422,218 individuals, and Frailty Index (FI) are derived from the latest GWAS dataset of 175,226 individuals. MR analysis is conducted using inverse variance weighting, MR-Egger, weighted median, simple mode, and weighted mode, supplemented by MRAPSS. Univariate MR revealed that sedentary behaviors such as watching television increased the risk of frailty (OR, 1.271; 95% CI: 1.202-1.345; p = 6.952 × 10-17), as sedentary driving behaviors are done (OR, 1.436; 95% CI: 1.026-2.011; p = 0.035). Further validation through APSS, taking into account cryptic relatedness, stratification, and sample overlap, maintained the association between television viewing and increased frailty risk (OR, 1.394; 95% CI: 1.266-1.534; p = 1.143 × 10-11), while the association with driving dissipated. In multivariate inverse variance weighted (IVW) analysis, after adjusting for C-reactive protein (CRP) levels, television Sedentary behavior (SB) inversely affected frailty (OR, 0.782; 95% CI: 0.724-0.845; p = 4.820 × 10-10). This study indicates that televisio SB significantly increases the risk of frailty, suggesting potential biological heterogeneity behind specific sedentary activities. This process may interact with inflammation, influencing the development of frailty.

Causal effects of blood pressure and the risk of frailty: a bi-directional two-sample Mendelian randomization study

Observational studies have indicated that high blood pressure (BP) may be a risk factor to frailty. However, the causal association between BP and frailty remains not well determined. The purpose of this bi-directional two-sample Mendelian randomization (MR) study was to investigate the causal relationship between BP and frailty. Independent single nucleotide polymorphisms (SNPs) strongly (P < 5E-08) associated with systolic BP (SBP), diastolic BP (DBP), and pulse pressure (PP) were selected as instrumental variables. Two different published genome-wide association studies (GWAS) on BP from the CHARGE (n = 810,865) and ICBP (n = 757,601) consortia were included. Summary-level data on frailty index (FI) were obtained from the latest GWAS based on UK Biobank and Swedish TwinGene cohorts (n = 175,226). Inverse variance weighted (IVW) approach with other sensitivity analyses were used to calculate the causal estimate. Using the CHARGE dataset, genetic predisposition to increased SBP (β = 0.135, 95% CI = 0.093 to 0.176, P = 1.73E-10), DBP (β = 0.145, 95% CI = 0.104 to 0.186, P = 3.14E-12), and PP (β = 0.114, 95% CI = 0.070 to 0.157, p = 2.87E-07) contributed to a higher FI, which was validated in the ICBP dataset. There was no significant causal effect of FI on SBP, DBP, and PP. Similar results were obtained from different MR methods, indicating good stability. There was potential heterogeneity detected by Cochran's Q test, but no horizontal pleiotropy was observed in MR-Egger intercept test (P > 0.05). These findings evinced that higher BP and PP were causally associated with an increased risk of frailty, suggesting that controlling hypertension could reduce the risk of frailty.

Exploration of the causality of frailty index on psoriasis: A Mendelian randomization study

BACKGROUND

Frailty is associated with a variety of diseases, but the relationship between frailty and psoriasis remains unclear.

METHODS

First, we conducted a two-sample Mendelian randomization based on genome-wide association studies (GWAS) to investigate genetic causality between frailty index and common diseases in dermatology. Inverse variance weighted was used to estimate causality. Second, expression quantitative trait locus (eQTLs) analysis was conducted to identify the genes affected by Single nucleotide polymorphisms (SNPs). Third, we performed function and pathway enrichment, transcriptome-wide association studies (TWAS) analysis based on eQTLs.

RESULTS

It was shown that the rise of frailty index could increase the risk of psoriasis (IVW, beta = 0.916, OR = 2.500, 95%CI:1.418-4.408, p = 0.002) through Mendelian randomization (MR), and there was no heterogeneity and pleiotropy. There was no causality between the frailty index and other common diseases in dermatology. We found 31 eQTLs based on strongly correlated SNPs in the causality. TWAS analysis found that the expressions of four genes were closely related to psoriasis, including HLA-DQA1, HLA-DQA2, HLA-DRB1 and HLA-DQB1.

CONCLUSION

It suggested that the frailty index had a significant positive causality on the risk of psoriasis, which was well documented by combined genomic, transcriptome, and proteome analyses.

Genetic predisposition to white blood cells in relation to the risk of frailty

BACKGROUND

Observational studies have suggested an association between white blood cells (WBCs) and frailty, but considering the susceptibility to reverse causality and confounding, the causal direction and magnitude of this association remain ambiguous. Our aim was to investigate the causal effect of WBCs on frailty by means of a Mendelian randomization (MR) analysis.

METHODS

Based on the genome-wide association study (GWAS) summary statistics data provided by the European Bioinformatics Institute (EBI), we carried out a two-sample MR study. We applied the genetically predicted independent WBCs from GWAS as a measure of exposure data. The Rockwood Frailty Index (FI) was used as outcome measure, which was derived from a meta-analysis from GWAS in UK Biobank European ancestry participants and Swedish TwinGene participants. Our study applied inverse variance weighted (IVW), weighted median, Mendelian randomization-Egger (MR-Egger) and outlier test (MR-PRESSO) methods to explore relationships between various WBCs and frailty.

RESULTS

In our study, a possible causal relationship between eosinophil levels and frailty was demonstrated by two-sample MR analysis. Eosinophils were associated with FI (beta:0.0609; 95% CI 0.0382, 0.0836; P = 1.38E-07). Our results suggest that as the level of eosinophils increases, so does the risk of frailty. No meaningful causal relationship between neutrophils, lymphocytes, monocytes or basophils and FI was found in the MR results (P > 0.05).

CONCLUSIONS

According to this MR study, higher eosinophil counts are related to an increased risk of frailty. To validate these findings and investigate the mechanisms underlying these connections, future studies are warranted.

Unraveling the metabolic underpinnings of frailty using multicohort observational and Mendelian randomization analyses

Identifying metabolic biomarkers of frailty, an age-related state of physiological decline, is important for understanding its metabolic underpinnings and developing preventive strategies. Here, we systematically examined 168 nuclear magnetic resonance-based metabolomic biomarkers and 32 clinical biomarkers for their associations with frailty. In up to 90,573 UK Biobank participants, we identified 59 biomarkers robustly and independently associated with the frailty index (FI). Of these, 34 associations were replicated in the Swedish TwinGene study (n = 11,025) and the Finnish Health 2000 Survey (n = 6073). Using two-sample Mendelian randomization, we showed that the genetically predicted level of glycoprotein acetyls, an inflammatory marker, was statistically significantly associated with an increased FI (β per SD increase = 0.37%, 95% confidence interval: 0.12-0.61). Creatinine and several lipoprotein lipids were also associated with increased FI, yet their effects were mostly driven by kidney and cardiometabolic diseases, respectively. Our findings provide new insights into the causal effects of metabolites on frailty and highlight the role of chronic inflammation underlying frailty development.