Current and emerging biomarkers of frailty in the elderly

Salivary Proteome, Inflammatory, and NETosis Biomarkers in Older Adult Practitioners and Nonpractitioners of Physical Exercise

Since aging has been associated with increased production of inflammatory biomarkers, the ability to monitor older adults repeatedly is highly desirable, and saliva is an interesting biofluid for the search of biomarkers, as it is easily accessible in a noninvasive manner. However, given the incipient knowledge of salivary biomarkers in aging and its relationship to physical exercise, the present study is aimed at evaluating the protein expression and the levels of inflammatory and NETosis biomarkers in the saliva of practitioners (PE) and nonpractitioners (NPE) of physical exercise older adults. Six (6) practitioner and 4 nonpractitioner older adults were enrolled in this study. Unstimulated whole saliva was collected for analysis of the proteome by label-free mass spectrometry, as well as of the inflammatory status by evaluation of C-reactive protein (CRP), vascular endothelial growth factor (VEGF), and cytokines (TNF-α, interleukin- (IL-) 1β, and IL-8), while NETosis was assessed by myeloperoxidase (MPO) and neutrophil elastase. Regarding oral health, the decayed, missing, and filled teeth (DMF-T) index, bleeding on probing, suppuration, and probing depth measurement (mm) were evaluated. In addition, functional capacity was investigated using the General Physical Fitness Index (GPFI). In relation to the proteome analysis, 93 and 143 proteins were found exclusively in the PE and NPE groups, respectively; 224 proteins were common to both groups. Among these proteins, 10 proteins showed statistical difference ( $p<0.05$ ) between the groups: alpha-2-macroglobulin, component 3 of the complement, serotransferrin, and protein soluble in brain acid 1 were less expressed, while lactotransferrin, alpha-amylase 1, S100-A8, S100-A9, lactoperoxidase, and galectin-3 binding protein were more expressed in the PE group. No differences between groups were observed in the analysis of inflammatory and NETosis biomarkers. This study shows the potential utility of saliva for detecting protein biomarkers in a noninvasive biological sample of the elderly population.

Biological Features of the Outcome-Based Intrinsic Capacity Composite Scores From a Population-Based Cohort Study: Pas de Deux of Biological and Functional Aging

Introduction

This study aims to develop and validate an integrative intrinsic capacity (IC) scoring system, to investigate its associations with a wide spectrum of biomarkers and to explore the predictive value of the integrative IC score on 4-year mortality among community dwelling people aged 50 years and older.

Methods

We included 839 adults aged ≥50 years from the Social Environment and Biomarkers of Aging Study (SEBAS) and randomly divided them into derivation and validation cohorts to develop the IC scoring system. The multivariate logistic regression model was used to weight each subdomain (locomotion, sensory, vitality, psychological, and cognition) of IC according to its association with impairments in instrumental activities of daily living (IADL) and to construct the integrative IC score. Age-related biomarkers and genetic markers were compared between IC groups by ordinal logistic regression. A Cox proportional hazard model was used to examine the association between IC and mortality, and subgroup analysis was used to assess the robustness of the results among participants aged 60 years and older.

Results

A 12-score IC scoring system (AUROC = 0.83; Hosmer–Lemeshow goodness-of-fit test p = 0.17) was developed, and higher scores indicated better intrinsic capacity. High interleukin (IL)-6, high E-selectin, low serum albumin and low folate were significantly associated with low IC in the whole sample. However, high IL-6, low serum albumin, low folate, high allostatic load, and APOE ε4 genotype were significantly associated with low IC in those aged 60 years old and older. Compared to the high IC group, the low IC group was significantly associated with all-cause mortality (HR: 2.50, 95% CI: 1.22–5.11, p = 0.01 for all participants; HR 2.19, 95% CI 1.03–4.64, p = 0.04 for participants aged 60 years and older).

Conclusions

The conceptually proposed IC can be easily transformed into a scoring system considering different weights of individual subdomains, which not only predicts mortality but also suggests different pathophysiologies across the life course of aging (inflammation, nutrition, stress, and ApoE4 genotype). An intervention study is needed using the composite IC score to promote healthy aging and determine the underlying pathophysiology.

Ageing with HIV: Challenges and biomarkers

The antiretroviral treatment (ART) developed to control HIV infection led to a revolution in the prognosis of people living with HIV (PLWH). PLWH underwent from suffering severe disease and often fatal complications at young ages to having a chronic condition and a life expectancy close to the general population. Nevertheless, chronic age-related diseases increase as PLWH age. The harmful effect of HIV infection on the individual's immune system adds to its deterioration during ageing, exacerbating comorbidities. In addition, PLWH are more exposed to risk factors affecting ageing, such as coinfections or harmful lifestyles. The ART initiation reverses the biological ageing process but only partially, and additionally can have some toxicities that influence ageing. Observational studies suggest premature ageing in PLWH. Therefore, there is considerable interest in the early prediction of unhealthy ageing through validated biomarkers, easy to implement in HIV-clinical settings. The most promising biomarkers are second-generation epigenetic clocks and integrative algorithms.

Composite Biomarkers for Assessing Frailty Status in Stable Older Adults With Cardiovascular Disease

Background: The relationship between frailty status and laboratory measurements in cardiovascular disease (CVD) remains unclear. We investigated which laboratory measurements indicated frailty in stable older CVD patients.

Methods and Results: One-hundred thirty-eight stable older CVD patients were evaluated by laboratory measurements, with frailty assessed using the Kihon Checklist (KCL). Laboratory measurements were compared between frail and non-frail groups. Across the entire cohort, mean age was 81.7 years, mean left ventricular ejection fraction was 57.8%, and mean plasma B-type natriuretic peptide was 182 pg/mL. KCL scores were used to divide patients into non-frail (n=43; KCL <8) and frail (n=95; KCL ≥8) groups. Serum iron was significantly lower in the frail than non-frail group (mean [±SD] 61.2±30.3 vs. 89.5±26.1 μg/dL, respectively; P<0.001). Blood urea nitrogen (BUN; 27.3±16.5 vs. 19.7±8.2 mg/dL; P=0.013) and C-reactive protein (CRP; 1.05±1.99 vs. 0.15±0.21 mg/dL; P=0.004) were significantly higher in the frail than non-frail group. Multivariate analysis revealed that serum iron, CRP, and BUN were significant independent predictors of frailty (β=−0.069, 0.917, and 0.086, respectively).

Conclusions: Frailty status was significantly associated with iron, CRP, and BUN in stable older CVD patients. Composite biomarkers (inflammation, iron deficiency, and renal perfusion) may be useful for assessing frailty in these patients.

Specific Metabolites Involved in Antioxidation and Mitochondrial Function Are Correlated With Frailty in Elderly Men

Background

As an age-related syndrome, frailty may play a central role in poor health among older adults. Sarcopenia overlaps with the physical domain of frailty, and most existing studies have analyzed the associated factors of frailty and sarcopenia as an isolated state. Perturbations in metabolism may play an important role in the presence of frailty or sarcopenia; however, the metabolites associated with frailty, especially overlapping with sarcopenia remain unclear. In this study, we aimed to explore whether amino acids, carnitines, acylcarnitines and lysophosphatidylcholines, as specific panels, are significantly correlated with frailty, especially overlapping with sarcopenia, to gain insight into potential biomarkers and possible biological mechanisms and to facilitate their management.

Methods

We applied a targeted high-performance liquid chromatography-tandem mass spectrometry approach in serum samples from 246 Chinese older men (age 79.2 ± 7.8 years) with frailty (n = 150), non-frailty (n = 96), frailty and sarcopenia (n = 52), non-frail and non-sarcopenic control (n = 85). Frailty was evaluated using Freid phenotype criteria, sarcopenia was defined by diagnostic algorithm of Asian Working Group on Sarcopenia, and the participants were diagnosed as frailty and sarcopenia when they met the evaluation criteria of both frailty and sarcopenia. A panel of 29 metabolomic profiles was assayed and included different classes of amino acids, carnitines, acylcarnitines, and lysophosphatidylcholines (LPCs). Multivariate logistic regression was used to screen the metabolic factors contributing to frailty status, and orthogonal partial least squares discriminant analysis was used to explore important factors and distinguish different groups.

Results

In older men demonstrating the frail phenotype, amino acid perturbations included lower tryptophan and higher glycine levels. With regard to lipid metabolism, the frailty phenotype was characterized by lower concentrations of isovalerylcarnitine (C5), LPC16:0 and LPC18:2, while higher levels of octanoyl-L-carnitine (C8), decanoyl-L-carnitine (C10), dodecanoyl-L-carnitine (C12) and tetradecanoyl-L-carnitine (C14). After adjusting for several clinical confounders, tryptophan, LPC18:2, LPC 16:0 and C5 were negatively correlated with frailty, and C8 and C12 were positively related to frailty. We preliminarily identified metabolic profiles (LPC16:0, LPC18:2, glycine and tryptophan) that may distinguish older men with frailty from those without frailty. Importantly, a set of serum amino acids and LPCs (LPC16:0, LPC18:2, and tryptophan) was characterized in the metabotype of older adults with an overlap of frailty and sarcopenia. The metabolites that were most discriminating of frailty status implied that the underlying mechanism might be involved in antioxidation and mitochondrial dysfunction.

Conclusions

These present metabolic analyses may provide valuable information on the potential biomarkers and possible biological mechanisms of frailty, and overlapping sarcopenia. The findings obtained may offer insight into their management in older adults.

miRNome Profiling Detects miR-101-3p and miR-142-5p as Putative Blood Biomarkers of Frailty Syndrome

Frailty is an aging-related pathology, defined as a state of increased vulnerability to stressors, leading to a limited capacity to meet homeostatic demands. Extracellular microRNAs (miRNAs) were proposed as potential biomarkers of various disease conditions, including age-related pathologies. The primary objective of this study was to identify blood miRNAs that could serve as potential biomarkers and candidate mechanisms of frailty. Using the Fried index, we enrolled 22 robust and 19 frail subjects. Blood and urine samples were analysed for several biochemical parameters. We observed that sTNF-R was robustly upregulated in the frail group, indicating the presence of an inflammatory state. Further, by RNA-seq, we profiled 2654 mature miRNAs in the whole blood of the two groups. Expression levels of selected differentially expressed miRNAs were validated by qPCR, and target prediction analyses were performed for the dysregulated miRNAs. We identified 2 miRNAs able to significantly differentiate frail patients from robust subjects. Both miR-101-3p and miR-142-5p were found to be downregulated in the frail vs. robust group. Finally, using bioinformatics targets prediction tools, we explored the potential molecular mechanisms and cellular pathways regulated by the two miRNAs and potentially involved in frailty.

Neuropsychiatric Disorders and Frailty in Older Adults over the Spectrum of Cancer: A Narrative Review

BACKGROUND

The interplay between different neuropsychiatric conditions, beyond dementia, in the presence of a diagnosis of cancer in older adults may mediate patients' fitness and cancer-related outcomes. Here, we aimed to investigate the presence of depression, sleep disturbances, anxiety, attitude, motivation, and support in older adults receiving a diagnosis of cancer and the dimension of frailty in order to understand the magnitude of the problem.

METHODS

This review provides an update of the state of the art based on references from searches of PubMed between 2000 and June 2021.

RESULTS

The evidence obtained underscored the tight association between frailty and unfavorable clinical outcomes in older adults with cancer. Given the intrinsic correlation of neuropsychiatric disorders with frailty in the realm of cancer survivorship, the evidence showed they might have a correlation with unfavorable clinical outcomes, late-life geriatric syndromes and higher degree of frailty.

CONCLUSIONS

The identification of common vulnerabilities among neuropsychiatric disorders, frailty, and cancer may hold promise to unmask similar shared pathways, potentially intercepting targeted new interventions over the spectrum of cancer with the delivery of better pathways of care for older adults with cancer.

Association between frailty and C-terminal agrin fragment with 3-month mortality following ST-elevation myocardial infarction

The objective of this study was to evaluate the association between frailty, evaluated by the Clinical Frailty Scale (CFS) and FRAIL scale, and C-terminal agrin fragment (CAF) levels with 3-month mortality following ST-segment elevation myocardial infarction (STEMI). This was a prospective observational study that included patients over the age of 18 years with STEMI admitted to the coronary intensive care unit. Within 48 h of admission, the CFS and FRAIL scale were applied and blood samples collected for serum CAF evaluation. Patients were followed for 3 months after hospital discharge, and mortality was recorded. One hundred and eleven patients were included; mean age was 62.3 ± 12.4 years, 61.3% were male and 11.7% died during the 3 months of follow-up. According to the CFS, 79.3% of the patients were classified as not frail, 12.6% as pre-frail and 8.1% as frail. According to the FRAIL scale, 31.5% of the patients were classified as not frail, 53.2% as pre-frail and 15.3% as frail. In univariate analysis, the CFS but not FRAIL scale was associated with mortality. In multiple logistic regression analysis, pre-frail/frail according to CFS (odds ratio [OR]: 6.118; CI 95%: 1.344-27.848; p = 0.019) and CAF levels (OR: 0.943; CI 95%: 0.896-0.992; p = 0.024) were associated with increased 3-month mortality. In a sub-analysis of 53 patients ≥65 years, CFS and CAF levels were associated with 3-month mortality. In conclusion, CAF levels and frailty determined by the CFS were associated with 3-month mortality after STEMI in the general and older population.

Iron Dysregulation and Frailty Syndrome

Patients with diagnosed frailty syndrome (FS) represent a special group of patients with chronic disease. In the classic definition, frailty syndrome includes such parameters as reduced muscle strength, subjective feeling of fatigue, unintentional weight loss, slow gait, and low physical activity. Frailty syndrome leads to an increased incidence of adverse events, such as falls, hospitalizations, and the need to place patients in care and health institutions associated with the loss of independence; frailty syndrome is also associated with an increased incidence of death. In European countries, the frequency of frailty syndrome in the geriatric population is estimated to be 17% with a range from 5.8% to 27%, and its incidence increases with age. A much higher percentage of frailty syndrome patients is also observed among hospitalized patients. The incidence of frailty syndrome is influenced by many socio-economic factors, but also medical factors. Materials and Methods: A total of 120 patients, >65 years of age, participated in the study. During the study, anthropometric measurements, surveys, laboratory determinations of basic biochemical parameters, and iron status were investigated; 5 mL of peripheral blood in EDTA was also collected for further laboratory tests of hepcidin and soluable transferrin receptor (sTfR) using ELISA. Then, the statistical analysis was performed based on survey and clinical data. Results: Among the patients >65 years of age, the incidence of frailty syndrome was 27.5%. It was found that its occurrence was associated with socio-economic factors, malnutrition, multiple morbidities, reduced muscle strength and gait speed, and polypharmacotherapy. The relationship between reduced iron concentration and the occurrence of frailty syndrome was confirmed. Conclusions: According to the analysis, it was found that a decrease in iron concentration was associated with frailty syndrome.

The correlation between nutrition and frailty and the receiver operating characteristic curve of different nutritional indexes for frailty

Background

Frailty is a kind of geriatric syndrome, which is very common in the elderly. Patients with malnutrition are at higher risk of frailty. This study explored the correlation between nutrition and frailty and compared the receiver operating characteristic curve of different nutritional indexes for frailty.

Methods

This cross-sectional study included 179 inpatients aged ≥65 years old. Frailty was measured using Fried Frailty Phenotype, handgrip strength was measured using JAMAR@Plus and the 4.57 m usual gait speed was measured using a stopwatch. Comprehensive nutritional assessment refers to the application of Mini Nutritional Assessment (MNA) to assess the nutritional status of patients.

Results

Compared with the non-frailty group, the upper arm circumference, calf circumference, hemoglobin, albumin, prealbumin, cholesterol and low density lipoprotein in the frailty group were lower (P < 0.05). Comprehensive nutritional assessment, whether as a categorical variable or a continuous variable, was significantly correlated with frailty (P < 0.05). Model1 showed that the risk of frailty in malnourished patients was 3.381 times higher than that in well nourished patients (P = 0.036). Model2 showed that the risk of frailty decreased by 13.8% for every 1 point increase in MNA score (P = 0.009). The area under the curves of albumin, prealbumin and hemoglobin was larger (AUC > 0.65), AUC was 0.718, 0.693 and 0.743, respectively.

Conclusions

Our results suggest that malnutrition is closely related to frailty. As for single nutritional indexes, albumin, prealbumin and hemoglobin were found to be associated with frailty. Further cohort studies are needed to verify their ability to screen for frailty.

Low ALT levels are associated with poor outcomes in acute coronary syndrome patients in the intensive cardiac care unit

BACKGROUND

Frailty is an underrecognized and important entity that bears worse prognosis. Although low serum alanine aminotransferase (ALT) can serve as a novel marker of frailty, its use was never assessed in acute coronary syndrome (ACS) patients.

METHODS

A retrospective analysis of hospitalized ACS patients in the intensive cardiac care unit (ICCU)between 1/5/2011 and 1/12/2020 at a single tertiary medical center.

RESULTS

The study included 3956 patients after excluding patients with ALT >40 IU/L, cirrhosis, and missing data, followed for a medianduration of 47 months (IQR 20-77).Patients were stratified into two groups based on their first ALT measurement within the index hospitalization: low-normal ALT group (ALT ≤10 IU/L) vs. high-normal ALT group (ALT >10 IU/L). Patients with ALT≤10 IU/L were older (mean age 71 years vs. 65 years, p<0.001), presented more frequently with non-ST elevation myocardial infarction (66.4% vs. 53.2%, p< 0.001), had higher rates of comorbiditiesat baseline, and had a lower Norton score upon admission. Hospitalization length was longer in the low-normal ALT group (p< 0.001). Although the in-hospital mortality rate was similar between the groups (0.9% vs. 0.7%, p = 0.99), long-termmortality was significantly higher in the low-normal ALT group (22.7% vs. 7.9%, p< 0.001). In a multivariate regression model ALT ≤10 IU/l was associated with increased mortality (HR 2.1, 95% CI 1.46-3).

CONCLUSIONS

Lower serum ALT is associated with worse outcomes in ACS patients admitted to the ICCU.

Current perspectives on defining and mitigating frailty in relation to critical illness

Up to half of ICU survivors, many of whom were premorbidly well, will have residual functional and/or cognitive impairment and be vulnerable to future health problems. Frailty describes vulnerability to poor resolution of homeostasis after a stressor event but it is not clear whether the vulnerability seen after ICU correlates with clinical measures of frailty. In clinical practice, the scales most commonly used in critically ill patients are based on the assessment of severity and survival. Identification and monitoring of frailty in the ICU may be an alternative or complimentary approach, particularly if it helps explain vulnerability during the recovery and rehabilitation period. The purpose of this review is to discuss the use of tools to assess frailty status in the critically ill, and consider their importance in clinical practice. Amongst these, we consider biomarkers with potential to identify patients at greater or lesser risk of developing post-ICU vulnerability.

Biological and Neuroimaging Markers as Predictors of 5-Year Incident Frailty in Older Adults: A Secondary Analysis of the MAPT Study

BACKGROUND

This study aims to investigate the predictive value of biological and neuroimaging markers to determine incident frailty among older people for a period of 5 years.

METHODS

We included 1394 adults aged 70 years and older from the Multidomain Alzheimer Preventive Trial, who were not frail at baseline (according to Fried's criteria) and who had at least 1 post-baseline measurement of frailty. Participants who progressed to frailty during the 5-year follow-up were categorized as "incident frailty" and those who remained non-frail were categorized as "without frailty." The differences of baseline biochemical factors (25-hydroxyvitamin D, homocysteine, omega-3 index, C-reactive protein), other biological markers (Apolipoprotein E genotypes, amyloid-β deposits), and neuroimaging data (gray matter volume, hippocampal volume, white matter hyperintensities) were compared between groups. Cox proportional hazard model was used to evaluate the associations between biomarkers and incident frailty.

RESULTS

A total of 195 participants (14.0%) became frail over 5 years. Although 25-hydroxyvitamin D deficiency, homocysteine levels, low-grade inflammation (persistently increased C-reactive protein 3-10 mg/L), gray matter, and hippocampal volume were significantly associated with incident frailty in unadjusted models, these associations disappeared after adjustment for age, sex, and other confounders. Omega-3 index was the sole marker that presented a trend of association with incident frailty (hazard ratio: 0.92; 95% confidence interval: 0.83-1.01; p = .082).

CONCLUSIONS

This study failed to identify biomarkers able to predict frailty incidence in community-dwelling older adults for a period of 5 years. Further longitudinal research with multiple measurements of biomarkers and frailty is needed to evaluate the long-term relationships between changes in biomarkers levels and frailty evolution.

Biosymbiotic, personalized, and digitally manufactured wireless devices for indefinite collection of high-fidelity biosignals

Digital medicine, the ability to stream continuous information from the body to gain insight into health status, manage disease, and predict onset health problems, is only gradually developing. Key technological hurdles that slow the proliferation of this approach are means by which clinical grade biosignals are continuously obtained without frequent user interaction. To overcome these hurdles, solutions in power supply and interface strategies that maintain high-fidelity readouts chronically are critical. This work introduces a previously unexplored class of devices that overcomes the limitations using digital manufacturing to tailor geometry, mechanics, electromagnetics, electronics, and fluidics to create unique personalized devices optimized to the wearer. These elastomeric, three-dimensional printed, and laser-structured constructs, called biosymbiotic devices, enable adhesive-free interfaces and the inclusion of high-performance, far-field energy harvesting to facilitate continuous wireless and battery-free operation of multimodal and multidevice, high-fidelity biosensing in an at-home setting without user interaction.

Consistent patterns in the inconsistent associations of Insulin-like growth factor 1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin 6 (IL-6) levels with delirium in surgical populations. A systematic review and meta-analysis

BACKGROUND

Biomarkers for delirium could increase diagnostic accuracy and may help to identify pathological pathways. Until now study findings concerning cytokine levels have been inconsistent.

AIMS

Systematic review and meta-analysis investigating the association between peripheral levels of Insulin-like Growth Factor-1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin-6 (IL-6) and delirium in surgical patients, and to explore if there are distinct/specific patterns that may potentially explain inconsistent results.

METHODS

PubMed, Scopus, CINAHL, Cochrane, and EMBASE databases were searched. Inclusion criteria were: prospective studies, surgical populations excluding preoperative delirium, available data. The following were collected: type of operation (orthopaedic, abdominal, etc), the timing of operation (acute, elective, both), demographics, number of participants with delirium, time of preoperative blood withdrawal, and preoperative levels of each biomarker.

RESULTS

Low levels of IGF-1 (n = 7 studies) are significantly associated with post-operative delirium in abdominal surgical samples. High levels of C-RP (n = 9) are associated with delirium in acute orthopaedic and elective abdominal operations. IL-6 (n = 14) is a significant predictor of post-operative delirium in a variety of surgical conditions (elective or acute).

DISCUSSION

A common pattern exists in the otherwise conflicting reported findings. This similarity may reflect different underling mechanisms and predisposing factors like cachexia and catabolic stages. It seems that delirium in abdominal surgery is triggered by IGF-1 disturbances, while in other surgeries by an inflammatory reaction.

CONCLUSIONS

Despite the contradictory results concerning the association of IGF-1, C-RP and IL-6 with postoperative delirium, the present meta-analysis shows that there are certain patterns. IL-6 seems a consistent predictor for delirium in surgical samples.

Pre-Frailty and Frailty in Dialysis and Pre-Dialysis Patients: A Systematic Review of Clinical and Biochemical Markers

Patients under dialysis are known to be more vulnerable to frailty, a dynamic geriatric syndrome defined as a state of vulnerability to stressors, due to numerous metabolic changes. With rise of life expectancy globally, it is important to understand the complexity of the pathophysiology of frailty and identify possible markers that can help with the prognosis and diagnosis of frailty. The aim of this systematic review is to give an overview of the knowledge regarding clinical and biochemical markers associated with pre-frailty and frailty in dialysis and pre-dialysis patients. In November 2020, PubMed, Embase and Web of Science were searched. Studies regarding biomarkers associated with (pre-)frailty in (pre-)dialysis patients were included. This systematic review identified clinical and biochemical markers in pre-frail and frail patients under dialysis or pre-dialysis published in the literature. This study shows that more investigation is necessary to identify markers that can differentiate these processes to be used as a diagnostic and prognostic tool in routine care and management of geriatric needs. Interventions that can improve health outcomes in pre-frail and frail older adults under dialysis or pre-dialysis are essential to improve not only the individual's quality of life but also to reduce the burden to the health systems.

The Emergency Surgery Frailty Index (EmSFI): development and internal validation of a novel simple bedside risk score for elderly patients undergoing emergency surgery

BACKGROUND

Frailty assessment has acquired an increasing importance in recent years and it has been demonstrated that this vulnerable profile predisposes elderly patients to a worse outcome after surgery. Therefore, it becomes paramount to perform an accurate stratification of surgical risk in elderly undergoing emergency surgery.

STUDY DESIGN

1024 patients older than 65 years who required urgent surgical procedures were prospectively recruited from 38 Italian centers participating to the multicentric FRAILESEL (Frailty and Emergency Surgery in the Elderly) study, between December 2016 and May 2017. A univariate analysis was carried out, with the purpose of developing a frailty index in emergency surgery called "EmSFI". Receiver operating characteristic curve analysis was then performed to test the accuracy of our predictive score.

RESULTS

784 elderly patients were consecutively enrolled, constituting the development set and results were validated considering further 240 consecutive patients undergoing colorectal surgical procedures. A logistic regression analysis was performed identifying different EmSFI risk classes. The model exhibited good accuracy as regard to mortality for both the development set (AUC = 0.731 [95% CI 0.654-0.772]; HL test χ² = 6.780; p = 0.238) and the validation set (AUC = 0.762 [95% CI 0.682-0.842]; HL test χ² = 7.238; p = 0.299). As concern morbidity, our model showed a moderate accuracy in the development group, whereas a poor discrimination ability was observed in the validation cohort.

CONCLUSIONS

The validated EmSFI represents a reliable and time-sparing tool, despite its discriminative value decreased regarding complications. Thus, further studies are needed to investigate specifically surgical settings, validating the EmSFI prognostic role in assessing the procedure-related morbidity risk.

Low Psoas Lumbar Vertebral Index Is Associated with Mortality after Hip Fracture Surgery in Elderly Patients: A Retrospective Analysis

The psoas-to-lumbar index (PLVI) has been reported as a simple and easy way to measure central sarcopenia. However, only few studies have evaluated the association between PLVI and survival in surgical patients. This study evaluated the association between preoperative PLVI and mortality in elderly patients who underwent hip fracture surgery. We retrospectively analyzed 615 patients who underwent hip fracture surgery between January 2014 and December 2018. The median value of each PLVI was calculated according to sex, and the patients were categorized into two groups on the basis of the median value (low PLVI group vs. high PLVI group). Cox regression analysis was performed to evaluate the risk factors for 1 year and overall mortalities. The median values of PLVI were 0.62 and 0.50 in men and women, respectively. In the Cox regression analysis, low PLVI was significantly associated with higher 1 year (hazard ratio (HR): 1.87, 95% confidence interval (CI): 1.18–2.96, p = 0.008) and overall mortalities (HR: 1.51, 95% CI: 1.12–2.03, p = 0.006). Low PLVI was significantly associated with a higher mortality. Therefore, PLVI might be an independent predictor of mortality in elderly patients undergoing hip fracture surgery.

Use of Multiprognostic Index Domain Scores, Clinical Data, and Machine Learning to Improve 12-Month Mortality Risk Prediction in Older Hospitalized Patients: Prospective Cohort Study

Background

The Multidimensional Prognostic Index (MPI) is an aggregate, comprehensive, geriatric assessment scoring system derived from eight domains that predict adverse outcomes, including 12-month mortality. However, the prediction accuracy of using the three MPI categories (mild, moderate, and severe risk) was relatively poor in a study of older hospitalized Australian patients. Prediction modeling using the component domains of the MPI together with additional clinical features and machine learning (ML) algorithms might improve prediction accuracy.

Objective

This study aims to assess whether the accuracy of prediction for 12-month mortality using logistic regression with maximum likelihood estimation (LR-MLE) with the 3-category MPI together with age and gender (feature set 1) can be improved with the addition of 10 clinical features (sodium, hemoglobin, albumin, creatinine, urea, urea-to-creatinine ratio, estimated glomerular filtration rate, C-reactive protein, BMI, and anticholinergic risk score; feature set 2) and the replacement of the 3-category MPI in feature sets 1 and 2 with the eight separate MPI domains (feature sets 3 and 4, respectively), and to assess the prediction accuracy of the ML algorithms using the same feature sets.

Methods

MPI and clinical features were collected from patients aged 65 years and above who were admitted to either the general medical or acute care of the elderly wards of a South Australian hospital between September 2015 and February 2017. The diagnostic accuracy of LR-MLE was assessed together with nine ML algorithms: decision trees, random forests, extreme gradient boosting (XGBoost), support-vector machines, naïve Bayes, K-nearest neighbors, ridge regression, logistic regression without regularization, and neural networks. A 70:30 training set:test set split of the data and a grid search of hyper-parameters with 10-fold cross-validation—was used during model training. The area under the curve was used as the primary measure of accuracy.

Results

A total of 737 patients (female: 370/737, 50.2%; male: 367/737, 49.8%) with a median age of 80 (IQR 72-86) years had complete MPI data recorded on admission and had completed the 12-month follow-up. The area under the receiver operating curve for LR-MLE was 0.632, 0.688, 0.738, and 0.757 for feature sets 1 to 4, respectively. The best overall accuracy for the nine ML algorithms was obtained using the XGBoost algorithm (0.635, 0.706, 0.756, and 0.757 for feature sets 1 to 4, respectively).

Conclusions

The use of MPI domains with LR-MLE considerably improved the prediction accuracy compared with that obtained using the traditional 3-category MPI. The XGBoost ML algorithm slightly improved accuracy compared with LR-MLE, and adding clinical data improved accuracy. These results build on previous work on the MPI and suggest that implementing risk scores based on MPI domains and clinical data by using ML prediction models can support clinical decision-making with respect to risk stratification for the follow-up care of older hospitalized patients.

Movement as a Positive Modulator of Aging

The aging of human populations, including those in Europe, is an indisputable fact. The challenge for the future is not simply prolonging human life at any cost or by any means but rather extending self-sufficiency and quality of life. Even in the most advanced societies, the eternal questions remain. Who will take care of the older generations? Will adult children’s own circumstances be sufficient to support family members as they age? For a range of complex reasons, including socioeconomic conditions, adult children are often unable or unwilling to assume responsibility for the care of older family members. For this reason, it is imperative that aging adults maintain their independence and self-care for as long as possible. Movement is an important part of self-sufficiency. Moreover, movement has been shown to improve patients’ clinical status. At a time when the coronavirus pandemic is disrupting the world, older people are among the most vulnerable. Our paper explores current knowledge and offers insights into the significant benefits of movement for the elderly, including improved immunity. We discuss the biochemical processes of aging and the counteractive effects of exercise and endogenous substances, such as vitamin D.

Identifying Biomarkers for Biological Age: Geroscience and the ICFSR Task Force

The International Conference on Frailty and Sarcopenia Research Task Force met in March 2020, in the shadow of the COVID-19 pandemic, to discuss strategies for advancing the interdisciplinary field of geroscience. Geroscience explores biological mechanisms of aging as targets for intervention that may delay the physiological consequences of aging, maintain function, and prevent frailty and disability. Priorities for clinical practice and research include identifying and validating a range of biomarkers of the hallmarks of aging. Potential biomarkers discussed included markers of mitochondrial dysfunction, proteostasis, stem cell dysfunction, nutrient sensing, genomic instability, telomere dysfunction, cellular senescence, and epigenetic changes. The FRAILOMICS initiative is exploring many of these through various omics studies. Translating this knowledge into new therapies is being addressed by the U.S. National Institute on Aging Translational Gerontology Branch. Research gaps identified by the Task Force include the need for improved cellular and animal models as well as more reliable and sensitive measures.

Muscle, endocrine, and immunological markers of frailty in older people

OBJECTIVE

To analyze muscle, endocrine, and immunological markers that influence frailty in older people assisted in primary care.

MATERIALS AND METHODS

Cross-sectional, analytical, and probabilistic study were linked to the institutional research "Integrated Health Care for Older People." The study population consisted of males and females aged 60 years or more and assisted in primary health care. The research protocol included an interview and physical examination to evaluate the frailty criteria. Analysis of the following were done: serum calcium and creatinine as muscle markers; vitamin D, parathyroid hormone, and insulin-like growth factor - 1 as endocrine markers; and interleukin-6, C-reactive protein, leukocytes, and neutrophil-lymphocyte ratio as immunological markers. Statistical analysis included the Mann-Whitney test to compare means, and linear regression to analyze the relationship between dependent and independent variables.

RESULTS

There was a relationship between creatinine and prediction of weight loss (p < 0.001), leukocytes and prediction of handgrip strength (p = 0.022), interleukin-6 and prediction of energy expenditure (p = 0.026), and vitamin D and prediction of gait time (p = 0.036). Also, sex influenced handgrip strength (p < 0.001), and age influenced handgrip strength (p < 0.001), gait time (p < 0.001) and energy expenditure (p < 0.001).

CONCLUSION

The joint use of muscle, endocrine, and immunological markers may be useful to diagnose frailty and to propose resolutive interventions to reduce negative outcomes for older people.

Blood-based biomarkers and long-term risk of frailty - experience from the Swedish AMORIS cohort

BACKGROUND

Frailty is associated with reduced quality of life, poor health outcomes, and death. Past studies have investigated how specific biomarkers are associated with frailty but understanding biomarkers in concert with each other and the associated risk of frailty is critical for clinical application.

METHODS

Using a sample aged ≥59 years at baseline from the Swedish AMORIS cohort (n=19341), with biomarkers measured at baseline (1985-1996), we conducted latent class analysis with 18 biomarkers and used Cox models to determine the association between class and frailty and all-cause mortality.

RESULTS

Four classes were identified. Compared to the largest class, the Reference class (81.7%), all other classes were associated with increased risk of both frailty and mortality. The Anemia class (5.8%), characterized by comparatively lower iron markers and higher inflammatory markers, had HR=1.54, 95% CI 1.38, 1.73 for frailty and HR=1.76, 95% CI 1.65, 1.87 for mortality. The Diabetes class (6.5%) was characterized by higher glucose and fructosamine, and had HR=1.59, 95% CI 1.43, 1.77 for frailty and HR=1.74, 95% CI 1.64, 1.85 for mortality. Finally, the Liver class (6.0%), characterized by higher liver enzyme levels, had HR=1.15, 95% CI 1.01, 1.30 for frailty and HR=1.40, 95% CI 1.31, 1.50 for mortality. Sex-stratified analyses did not show any substantial differences between men and women.

CONCLUSIONS

Distinct sets of commonly available biomarkers were associated with development of frailty and monitoring these biomarkers in patients may allow for earlier detection and possible prevention of frailty, with the potential for improved quality of life.

Effect Modification by Sex of the Hemoglobin Concentration on Frailty Risk in Hospitalized Older Patients

Background

Hemoglobin concentration differs by sex, possibly affecting any association between hemoglobin and frailty. This study aimed to evaluate the potential interaction effect of hemoglobin and sex on frailty in Chinese older inpatients.

Methods

A cross-sectional study was conducted between February 2015 and November 2017 in a tertiary hospital. Frailty was defined by the Fried phenotype. Hemoglobin concentration was measured with a standard procedure. Covariates included demographics, clinical characteristics, and serum biomarkers. Logistic regression was applied to examine the association between hemoglobin concentration and frailty. The relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (SI) were used to evaluate the additive interaction.

Results

A total of 619 older inpatients [mean age 69.26±7.44 years; 334 men, 285 women] were included. The mean hemoglobin concentration was significantly lower in the elderly who were frail (11.9 g/L in frail versus 13.1g/L in non-frail; p<0.001). In the multivariable regression models, lower hemoglobin in patients was significantly associated with frailty (adjusted odds ratio (OR) = 2.51, 95% CI:1.37, 4.60). The stratified analyses indicated that lower hemoglobin was associated with frailty among older inpatients with different characteristics. Female inpatients with lower hemoglobin had the highest risk of frailty (adjusted OR=6.43, 95%: 2.38, 17.3); there were interactions between hemoglobin and sex on the development of frailty (RERI=4.30, 95% CI=−1.41, 10.01; AP=0.67, 95% CI=0.37, 0.97;SI=4.80, 95% CI=1.22, 18.84).

Conclusions and Implications

Our study provided evidence that sex and lower hemoglobin have an interaction effect on frailty; it is suggested that clinicians may consider sex-specific strategies for the elderly to conform the concept of precision medicine.

Chondroprotective effect of Alpinia oxyphylla extract in experimentally induced cartilage degradation in rabbit articular cartilage explants

Alpinia oxyphylla is a widely used medicinal herb for diarrhea, gastralgia, tumors, hypertention, and cerebrovascular disorders. Here, we evaluated the chondroprotective effect of A. oxyphylla dried fruit ethanol extract (AOE) against cartilage degradation in rabbit articular cartilage explants. Treatment of interleukin-1α (IL-1α) and plasminogen increased degraded collagen release in culture supernatants, but pretreatment of AOE (50, 100, 200 µg/ml) inhibited the collagen release in dose-dependent manner. To examine the mechanism of action of AOE on chondroprotection, the level of matrix metalloproteinases-3 (MMP-3), matrix metalloproteinases-13 (MMP-13), tissue inhibitor of metalloprotease-1 (TIMP-1), and inflammatory mediators like prostaglandin E₂ (PGE₂ ) and nitric oxide (NO) was evaluated. AOE inhibited upregulation of MMP-3 and MMP-13 and downregulation of TIMP-1 and also reduced increase of PGE₂ and NO level induced by exposure of IL-1α and plasminogen. These results indicate that AOE show chondroprotective effect through inhibiting collagen degradation via regulating MMPs, TIMP-1, and inflammatory mediators. PRACTICAL APPLICATIONS: Osteoarthritis (OA) is a one of the most common chronic disorders in elderly persons. Because the regenerative power of joint articular cartilage is very low, treatment of OA is difficult to expect complete recovery. Therefore, there is a need to develop a therapeutic agent that can safely and effectively inhibit the cartilage destruction. For the first time, we exhibited the inhibitory effect of AOE on collagen degradation through regulating MMPs and TIMP-1 in articular cartilage explants. These findings support AOE could be used as herbal therapeutic application for protecting articular cartilage to prevent OA.

Inflammaging markers characteristic of advanced age show similar levels with frailty and dependency

The improvement of life quality and medical advances has resulted in increased life expectancy. Despite this, health status commonly worsens in the last years of life. Frailty is an intermediate and reversible state that often precedes dependency and therefore, its identification may be essential to prevent dependency. However, there is no consensus on the best tools to identify frailty. In this sense, diverse molecules have been proposed as potential biomarkers. Some investigations pointed to an increased chronic inflammation or inflammaging with frailty, while others did not report such differences. In this work, we evaluated the circulating concentration of the inflammaging markers in adults and older adults (aged over 70 years) by ELISA and Luminex techniques. The Barthel Index was applied for the evaluation of dependency and Timed up-and-go, Gait Speed, Short Physical Performance Battery, Tilburg Frailty Indicator and Gerontopole Frailty Screening Tool were used for the identification of frailty. CRP, TNF-α, IL-6 and albumin concentrations were measured, and we found that elevated inflammation is present in older adults, while no differences with frailty and dependency were reported. Our results were consistent for all the evaluated frailty scales, highlighting the need to reconsider increased inflammation as a biomarker of frailty.

Frailty in Lung Transplantation - Candidate Assessment and Optimization

The concept of frailty has gained considerable interest in clinical solid organ transplantation over the past decade. Frailty as a phenotypic construct to describe a patient's risk from biologic stresses, has an impact on posttransplant survival. There is keen interest in characterizing frailty in lung transplantation, both to determine which patients are suitable candidates for listing and also to prepare for their care in the aftermath of lung transplantation. Here we review the current status of research on frailty in lung transplant candidates and recipients. This review will highlight areas of uncertainty for frailty in clinical lung transplantation which are likely to impact the state-of-the-art in the field for the next decade.

Aging and Allostasis: Using Bayesian Network Analytics to Explore and Evaluate Allostatic Markers in the Context of Aging

Allostatic load reflects the cumulative strain on organic functions that may gradually evolve into overt disease. Our aim was to evaluate the allostatic parameters in the context of aging, and identify the parameters that may be suitable for an allostatic load index for elderly people (>60 years). From previously published studies, 11 allostatic (bio)markers could be identified that sustain sufficient variability with aging to capture meaningful changes in health status. Based on reported statistics (prevalence of a biomarker and its associated outcome, and/or an odds/risk ratio relating these two), seven of these could be adopted in a Bayesian Belief Network (BBN), providing the probability of “disturbed” allostasis in any given elder. Additional statistical analyses showed that changes in IL-6 and BMI contributed the most to a “disturbed” allostasis, indicating their prognostic potential in relation to deteriorating health in otherwise generally healthy elderly. In this way, and despite the natural decline in variance that irrevocably alters the prognostic relevance of most allostatic (bio)markers with aging, it appeared possible to outline an allostatic load index specifically for the elderly. The allostatic parameters here identified might consequently be considered a useful basis for future quantitative modelling in the context of (healthy) aging.

System models for resilience in gerontology: application to the COVID-19 pandemic

The care needs for aging adults are increasing burdens on health systems around the world. Efforts minimizing risk to improve quality of life and aging have proven moderately successful, but acute shocks and chronic stressors to an individual's systemic physical and cognitive functions may accelerate their inevitable degradations. A framework for resilience to the challenges associated with aging is required to complement on-going risk reduction policies, programs and interventions. Studies measuring resilience among the elderly at the individual level have not produced a standard methodology. Moreover, resilience measurements need to incorporate external structural and system-level factors that determine the resources that adults can access while recovering from aging-related adversities. We use the National Academies of Science conceptualization of resilience for natural disasters to frame resilience for aging adults. This enables development of a generalized theory of resilience for different individual and structural contexts and populations, including a specific application to the COVID-19 pandemic.

Clinical Frailty Scale and Biomarkers for Assessing Frailty in Elder Inpatients in China

OBJECTIVE

This study aimed to assess the feasibility of the Clinical Frailty Scale (CFS) and clinical biomarkers in assessing the frailty in elder inpatients in China.

DESIGN

The study was a cross-sectional study.

SETTING AND PARTICIPANTS

The study included 642 elder inpatients (295 females and 347 males) aged ≥65 years, from the Department of Geriatrics of Zhejiang Hospital between January 2018 and December 2019.

MEASUREMENTS

All participants underwent a comprehensive geriatric assessment and blood tests. Univariate and multivariate logistic regression was used to analyze the association between risk factors and frailty.

RESULTS

The average age of the participants was 82.72±8.06 years (range: 65-95 years) and the prevalence of frailty was 39.1% according to the CFS. Frail participants showed significantly lower short physical performance battery (SPPB), basic activities of daily living (ADL) and instrumental activities of daily living (IADL) scores (all p<0.001), and lower hemoglobin, total protein and albumin levels (all P<0.05) than nonfrail participants. Frail participants had higher CRP, D-dimer and fibrinogen levels than nonfrail participants (all p<0.05). Univariate logistic regression analysis showed a significant association between frailty and age, comorbidity, polypharmacy, fall history, SPPB, ADL, and IADL scores, D-dimer, fibrinogen, hemoglobin, total protein and albumin levels (all P<0.05). Multivariate logistic regression analysis indicated that age (odds ratio (OR), 95% confidence interval (CI)= 1.151(1.042-1.272), P=0.006), SPPB scores (OR, 95% CI=0.901(0.601-1.350), P<0.001), and D-dimer (OR, 95% CI=4.857(2.182-6.983), P<0.001), fibrinogen (OR, 95% CI=2.665(0.977-4.254), P<0.001), hemoglobin (OR, 95% CI=0.837(0.725-0.963), P= 0.044), and albumin (OR, 95% CI=0.860 (0.776-1.188), P<0.001) levels were independently associated with frailty in all participants.

CONCLUSION

Frailty in elder inpatients in China is characterized by older age, a lower SPPB scores, higher D-dimer and fibrinogen levels and lower hemoglobin and albumin levels. Functional decline and malnutrition may be the targets of frailty interventions.

Trimethylamine N-Oxide, a Gut Microbiota-Dependent Metabolite, is Associated with Frailty in Older Adults with Cardiovascular Disease

Objective

Our study aimed to explore the association between trimethylamine N-oxide and frailty in older adults with cardiovascular disease.

Patients and Methods

This cross-sectional study analyzed a total of 451 people aged 65 years or older who underwent comprehensive geriatric assessments. Frailty status was determined using a frailty index constructed with 48 variables according to the cumulative deficits model. Physical frailty and cognitive frailty were also assessed in detail. Fasting plasma TMAO was measured by mass spectrometry.

Results

The proportion of frail subjects was 29.9% (135/451). Plasma TMAO levels were significantly higher in frail patients than in nonfrail individuals (4.04 [2.84–7.01] vs 3.21 [2.13–5.03] µM; p<0.001). Elevated plasma TMAO levels were independently associated with the likelihood of frailty (OR 2.12, 95% CI 1.01–4.38, p=0.046). Dose–response analysis revealed a linear association between the TMAO concentration and the OR for frailty. A 2-unit increase in TMAO was independently correlated with physical frailty (OR 1.23, 95% CI 1.08–1.41, p for trend 0.002) and cognitive frailty (OR 1.21, 95% CI 1.01–1.45, p for trend 0.04).

Conclusion

Elevated circulating TMAO levels are independently associated with frailty among older adults with cardiovascular disease.

Gerobiotics: probiotics targeting fundamental aging processes

Aging is recognized as a common risk factor for many chronic diseases and functional decline. The newly emerging field of geroscience is an interdisciplinary field that aims to understand the molecular and cellular mechanisms of aging. Several fundamental biological processes have been proposed as hallmarks of aging. The proposition of the geroscience hypothesis is that targeting holistically these highly integrated hallmarks could be an effective approach to preventing the pathogenesis of age-related diseases jointly, thereby improving the health span of most individuals. There is a growing awareness concerning the benefits of the prophylactic use of probiotics in maintaining health and improving quality of life in the elderly population. In view of the rapid progress in geroscience research, a new emphasis on geroscience-based probiotics is in high demand, and such probiotics require extensive preclinical and clinical research to support their functional efficacy. Here we propose a new term, "gerobiotics", to define those probiotic strains and their derived postbiotics and para-probiotics that are able to beneficially attenuate the fundamental mechanisms of aging, reduce physiological aging processes, and thereby expand the health span of the host. We provide a thorough discussion of why the coining of a new term is warranted instead of just referring to these probiotics as anti-aging probiotics or with other similar terms. In this review, we highlight the needs and importance of the new field of gerobiotics, past and currently on-going research and development in the field, biomarkers for potential targets, and recommended steps for the development of gerobiotic products. Use of gerobiotics could be a promising intervention strategy to improve health span and longevity of humans in the future.

Frail older adults show a distinct plasma microvesicle profile suggesting a prothrombotic and proinflammatory phenotype

In a global context of advanced aging, geriatric diseases such as frailty syndrome face challenges in the search for biomarkers and preventive strategies. Frailty has been associated with atherothrombotic pathologies. Circulating microvesicles (cMVs), phospholipid-rich vesicles with a size of 0.1-1.0 μm, have been shown to participate in atherothrombosis onset and progression. We have hypothesized that cMVs from platelets, and vascular and immune cells, are increased in frail older adults. To verify this, a prevalent-case control study was designed with 28 frail older and 27 nonfrail older adults older than 64 years. Frailty was defined by Fried's phenotype. Total cMVs, annexin V positive (AV+)-cMVs, and annexin V negative (AV^- )-cMVs derived from blood and vascular cells were measured by flow cytometry. In the analysis of total cMVs, the frail group presented higher levels of CD14⁺ /CD142⁺ (p = .042), CD41a⁺ /CD142⁺ (p = .041), and CD56⁺ (p = .025), CD14⁺ cMVs (p = .043), and CD16⁺ /CD14⁺ (p = .019) cMVs levels. Within the phosphatidylserine-exposing cMVs (AV⁺ ), the frail group showed higher CD14⁺ /AV⁺ (p = .044), CD9⁺ /AV⁺ (p = .031), P2RY12⁺ /AV⁺ (p = .028), and CD235a⁺ /AV⁺ (p = .043) cMVs concentrations. Finally, within AV^- cMVs, the frail group showed higher CD142⁺ /CD41a⁺ /AV^- cMVs concentrations originated from platelets (p = .027), CD56⁺ /AV^- originated from natural killer cells (p = .022), and CD34⁺ /AV^- cMVs from hematopoietic stem cells (p = .037). In summary, frail older adults present higher concentrations of platelet-, leukocyte-, and hematopoietic cell-derived cMVs compared to robust age-matched older adults. These cMVs may be involved in the deregulation of the immune system, endothelial damage, and increased risk of thrombosis associated with frailty.

Omics biomarkers for frailty in older adults

Frailty is a clinical state characterized by an age-related unsteady state of the body, a decline in physiological function, and an increased vulnerability to adverse outcomes. Early diagnosis of frailty is important for improving the quality of life in older adults and promoting healthy aging. The biological mechanisms underlying frailty have been extensively studied in recent years. Combining assessment tools and biomarkers can facilitate the early diagnosis of frailty. However, there is a lack of stable and reliable frailty-related biomarkers for use in clinical practice. Advances in the multi-omics platforms have provided new information on the molecular mechanisms underlying frailty. Thus, identifying biomarkers using omics-based approaches helps explore the physiological mechanisms underlying frailty, and aids the evaluation of the risk of frailty development and progression. This article reviews the current status of frailty biomarkers from the genomics, transcriptomics, proteomics, and metabolomics perspectives.

An opinion paper on the maintenance of robustness: Towards a multimodal and intergenerational approach using digital twins

The increasing number of frail elderly people in our aging society is becoming problematic: about 11% of community‐dwelling older persons are frail and another 42% are pre‐frail. Consequently, a major challenge in the coming years will be to test people over the age of 60 years to detect pre‐frailty at the earliest stage and to return them to robustness using the targeted interventions that are becoming increasingly available. This challenge requires individual longitudinal monitoring (ILM) or follow‐up of community‐dwelling older persons using quantitative approaches. This paper briefly describes an effort to tackle this challenge. Extending the detection of the pre‐frail stages to other population groups is also suggested. Appropriate algorithms have been used to begin the tracing of faint physiological signals in order to detect transitions from robustness to pre‐frailty states and from pre‐frailty to frailty states. It is hoped that these studies will allow older adults to receive preventive treatment at the correct institutions and by the appropriate professionals as early as possible, which will prevent loss of autonomy. Altogether, ILM is conceived as an emerging property of databases (“digital twins”) and not the reverse. Furthermore, ILM should facilitate a coordinated set of actions by the caregivers, which is a complex challenge in itself. This approach should be gradually extended to all ages, because frailty has no age, as is testified by overwork, burnout, and post‐traumatic syndrome.

Complementing chronic frailty assessment at hospital admission with an electronic frailty index (FI-Laboratory) comprising routine blood test results

BACKGROUND

Acutely ill and frail older adults have complex social and health care needs. It is important to understand how this complexity affects acute outcomes for admission to hospital. We validated a frailty index using routine admission laboratory tests with outcomes after patients were admitted to hospital.

METHODS

In a prospective cohort of older adults admitted to a large tertiary hospital in the United Kingdom, we created a frailty index from routine admission laboratory investigations (FI-Laboratory) linked to data comprising hospital outcomes. We evaluated the association between the FI-Laboratory and total days spent in hospital, discharge to a higher level of care, readmission and mortality.

RESULTS

Of 2552 admissions among 1750 older adults, we were able to generate FI-Laboratory values for 2254 admissions (88.3% of the cohort). More than half of admitted patients were women (55.3%) and the mean age was 84.6 (SD 14.0) years. We found that the FI-Laboratory correlated weakly with the Clinical Frailty Scale (CFS; r ² = 0.09). An increase in the CFS and the equivalent of 3 additional abnormal laboratory test results in the FI-Laboratory, respectively, were associated with an increased proportion of inpatient days (rate ratios [RRs] 1.43, 95% confidence interval [CI] 1.35-1.52; and 1.47, 95% CI 1.41-1.54), discharge to a higher level of care (odd ratios [ORs] 1.39, 95% CI 1.27-1.52; and 1.30, 95% CI 1.16-1.47) and increased readmission rate (hazard ratios [HRs] 1.26, 95% CI 1.17-1.37; and 1.18, 95% CI 1.11-1.26). Increases in the CFS and FI-Laboratory were associated with increased mortality HRs of 1.39 (95% CI 1.28-1.51) and 1.45 (95% CI 1.37-1.54), respectively.

INTERPRETATION

We determined that FI-Laboratory, distinct from baseline frailty, could be used to predict risk of many adverse outcomes. The score is therefore a useful way to quantify the degree of acute illness in frail older adults.

Pathobiology of frailty in lung disease

Frailty is a clinical state of vulnerability to stressors resulting from cumulative alterations in multiple physiological and molecular systems. Frailty assessment in patients with chronic disease is useful for identifying those who are at increased risk for poor clinical and patient reported outcomes. Due to biobehavioral changes purported to cause both frailty and certain chronic lung diseases, patients with lung disease appear susceptible to frailty and prone to developing it decades earlier than community dwelling healthy populations. Herein, we review the literature and potential pathobiological mechanisms underpinning associations between frailty in lung disease and age, sex, comorbidity and symptom burden, severity of lung disease, inflammatory biomarkers, various clinical parameters, body composition measures, and physical activity levels. We also propose a multipronged program of future research focused on improving the accuracy and precision of frailty measurement in lung disease, identifying blood-based biomarkers and measures of body composition for frailty, determining whether subphenotypes of frailty with distinct pathobiology exist, and developing personalized interventions that target the specific underlying mechanisms causing frailty.

Interleukin-6 and Lymphocyte Count Associated and Predicted the Progression of Frailty Syndrome in Prostate Cancer Patients Undergoing Antiandrogen Therapy

Frailty syndrome is a functional state that includes a loss of ability to react to stressors, and is associated with poor outcomes, morbidity and premature mortality. The first line treatment in many men with prostate cancer (PCa) consists of an androgen-deprivation therapy (ADT) which can promote or favor frailty syndrome and ADT may therefore favor the progression of frailty over time. Among the pathophysiological bases of frailty, the presence of chronic low-grade inflammation has been associated with its adverse outcomes, but longitudinal studies are needed to validate these biomarkers. In this study, we prospectively evaluate frailty syndrome and blood inflammatory markers (IL1-beta, IL-6, IL-8, TNF alpha, C reactive protein) and leukocytes were measured at baseline and an average of 1 year later in PCa under ADT. Frailty was defined as having three or more of the following components: low lean mass, weakness, self-reported exhaustion, low activity level, and slow walking speed; prefrailty was defined as having one or two of those components. Multinomial regression analysis showed that among the inflammatory biomarkers, those significantly and repeatedly (baseline and follow-up time points) (p < 0.05) associated with frailty syndrome were high IL-6 levels and low lymphocyte counts in blood. Other biomarkers such as IL-8, monocyte counts and C reactive protein were significantly associated with frailty syndrome (p < 0.05) in cross-sectional analyses, but they do not predict frailty progression at 1 year-follow-up. Receiver operating characteristic curve analysis showed that both lymphocyte counts and IL-6 concentration significantly (p < 0.05) (although moderately) discriminate PCa patients that progressed in the severity of frailty syndrome. IL-6 and lymphocytes count are possible biomarkers, useful for identifying frail patients and predicting the progression of frailty in PCa under ADT. Our study suggests the use of these biomarkers to guide clinical decisions on prostate cancer treatment based on a multidisciplinary approach.

Circulating biomarkers characterizing physical frailty: CRP, hemoglobin, albumin, 25OHD and free testosterone as best biomarkers. Results of a meta-analysis

INTRODUCTION

During aging, individuals can be classified as being in one of 3 different states: robust, frail or dependent. Frailty is described as reversible, so early detection offers the potential of returning the subject to a robust status. There are multiple clinical frailty scales but no gold standard and frailty is not systematically assessed in clinicians' daily practice. Reliable biomarkers of frailty are lacking, however, while their identification and systematic use would make this simple scale a useful clinical tool.

OBJECTIVE

To conduct a review of the literature concerning the biomarkers associated with frailty and to compare in a meta-analysis the plasmatic values of each biomarker in the frail with the robust group.

RESULTS

503 articles were identified on PubMed, 467 on Scopus and 369 on Web Of Science. 67 articles were included, collecting a total of 32,934 robust subjects and 6864 frail subjects. C-reactive protein (CRP) (Standardized Mean Difference (SMD): 0.49 CI 95% [0.37-0.61]) was significantly higher in the frail group whereas hemoglobin (SMD: -0.67[-0.90; -0.44]), albumin (SMD: -0.62[-0.84; -0.41]), 25-hydroxyvitamin D (25OHD) (SMD: -0.43 [-0.64; -0.21]) and, in men, free testosterone (SMD: -0.77 [-1.05; -0.49]) were significantly lower in the frail group.

CONCLUSION

We found 5 biomarkers that were associated with frailty (CRP, hemoglobin, albumin, 25OHD and free testosterone in men) belonging to multiple physiological systems. Further cohort studies are needed to verify their ability to screen for frailty.

Defining the vulnerable patient with myeloma-a frailty position paper of the European Myeloma Network

As the treatment landscape continues to evolve towards the application of precision medicine in multiple myeloma (MM), there is a clear need to identify those patients who are at risk of not achieving the maximum benefit whilst exposed to the highest level of toxicity. This group of patients, defined as frail, is an unmet clinical need. However, how we define such a vulnerable group of patients with MM remains to be clarified. An integral aspect of this is to define the physiological age and capacity of patients with MM to deal with the burden of their disease and it's treatment. Such assessments may include not only functional and clinical assessments but also laboratory-based biomarkers of frailty, aging and senescent cellular burden. A need to develop, test and validate clinical screening scores before their adoption into clinical practice is mandated. This position paper from the European Myeloma Network aims to review what is known about defining frailty in MM, and how we can advance this knowledge for the design of clinical trials and ultimately how we deliver treatment in the clinic.

Urinary 8-oxo-7,8-dihydroguanosine as a potential biomarker of frailty for elderly patients with cardiovascular disease

The diagnosis of frailty is usually subjective, which calls for objective biomarkers in clinical medicine. 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGsn) and 8-oxo-7, 8-dihydroguanosine (8-oxoGsn) in urine are two aging biomarkers that have not been explored deeply in cases of frailty. A total of 508 elderly patients with cardiovascular disease (mean age 75.0 ± 6.5 years, 50.8% males) were enrolled consecutively. Frailty was assessed by the Fried phenotype (robust: 0 score; pre-frail: 1-2 scores; frail: 3-5 scores). The concentrations of 8-oxoGsn and 8-oxodGsn in urine were measured by improved ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Urinary creatinine (Cre) was tested to correct the 8-oxoGsn and 8-oxodGsn levels. According to the Fried phenotype score, the proportions of robust, pre-frail, and frail subjects were 20.5% (104/508), 53.9% (274/508), and 25.6% (130/508), respectively. The urinary 8-oxoGsn/Cre (P < 0.001) differed significantly among these 3 groups, but the urinary 8-oxodGsn/Cre (P = 0.600) showed no marked difference. Univariate and multivariate logistic regression showed that the age (odds ratio [OR] = 1.090, P < 0.001), systolic blood pressure (OR = 0.981, P = 0.008), 8-oxoGsn/Cre (OR = 1.203, P = 0.007), hemoglobin (OR = 0.980, P = 0.007), and sodium (OR = 0.915, P = 0.044) were independently associated with frailty. The sensitivity and specificity to identify frailty were 53.08% and 71.96%, respectively, for 8-oxoGsn/Cre at the optimal cut-off value of 3.879 μmol/mol according to the maximal Youden index. Urinary 8-oxoGsn, as a recognized biomarker of RNA oxidation, is independently associated with frailty in elderly patients with cardiovascular disease. However, the urinary 8-oxodGsn shows no obvious correlation with frailty. To obtain a better diagnostic performance for frailty, more biomarkers from different pathophysiological pathways should be explored in the future.

Frailty syndrome, biomarkers and environmental factors - A pilot study

Frailty is an age-related syndrome expected to increase over the next decades. This syndrome has been identified to be the most common condition leading to disability, institutionalisation and death in the elderly. The aim of this pilot study is to investigate a possible link between frailty status, biomarkers and environmental exposures. A group of 71 older adults (≥65 years old) was engaged in this study. The study population was classified as 45.1% robust, 45.1% pre-frail and 9.8% frail. A significant higher prevalence of second-hand smokers was found in the pre-frail group when compared to robust. Furthermore, a higher prevalence of robust individuals was found among those consuming home-produced vegetables and water from well/springs. Significant differences were found between data collected in a lifetime exposure questionnaire (LTEQ) and the levels of genotoxicity endpoints and the mercury levels analysed regarding some exposure-related parameters, namely, smoking habits, intake of home-produced vegetables and the use of pesticides in agriculture. Understanding if the way we live(d) or worked can impact the way we age are important questions to be explored. Data obtained in this pilot study encourage further studies on this matter, exploring the role of exposures history and its impact on health.

Durability of glycaemic control in patients with type 2 diabetes after metformin failure: Prognostic model derivation and validation using the DISCOVER study

AIM

To develop and internally validate prognostic models on the long-term durability of glycaemic control in patients with type 2 diabetes after metformin failure.

MATERIALS AND METHODS

DISCOVER is a 3-year, prospective observational study across six continents investigating second-line glucose-lowering therapies. In this analysis from 35 countries, we included patients on metformin initiating second-line glucose-lowering medication(s) because of physician-defined lack of efficacy. The outcome was durability of glycaemic control, defined as three consecutive levels of HbA1c at 6-, 12- and 24-month follow-up at target (HbA1c equal to or lower than the level when the physician initiated the second-line therapy in patients with baseline HbA1c ≤7% [53 mmol/mol]; and equal to or lower than 7% in those with baseline HbA1c >7%). We developed and internally validated two prognostic models: a base model, which included age, sex, ethnicity, country income group, baseline HbA1c and second-line therapy, and an advanced model, established through statistical variable selections from a model including base variables and 13 additional predictors selected from a literature review. We used logistic regression to develop and 500 bootstrapping samples to internally validate the models; discrimination and calibration were used to assess model performance.

RESULTS

Overall, 896 out of 2995 participants (29.9%) had sustained glycaemic control. The base model performed well: Nagelkerke R² was 0.13, C-index 0.70 (95% CI: 0.68, 0.71) and bias-corrected C-index 0.69 after internal validation. Diabetes duration, insurance type, estimated glomerular filtration rate and glucose self-monitoring were additionally selected in the advanced model, which had only a slightly better performance compared with the base model: Nagelkerke R² 0.20, C-index 0.71 (95% CI: 0.69, 0.73) and bias-corrected C-index 0.70. Calibration plots showed good calibrations of both validated models.

CONCLUSION

These prognostic models, which include simple demographic and routinely collected clinical information, enabled the estimation of the probability of 2-year sustained glycaemic control in patients after metformin failure. The models have been implemented into a web-based tool to support healthcare professionals in their decisions.