The association between frailty, the metabolic syndrome, and mortality over the lifespan

Nutrition for the older adult - Current concepts. Report from an ESPEN symposium

BACKGROUND & AIMS

In view of the global demographic shift, a scientific symposium was organised by the European Society for Clinical Nutrition and Metabolism (ESPEN) to address nutrition-related challenges of the older population and provide an overview of the current state of knowledge.

METHODS

Eighteen nutrition-related issues of the ageing global society were presented by international experts during the symposium and summarised in this report.

RESULTS

Anorexia of ageing, dysphagia, malnutrition, frailty, sarcopenia, sarcopenic obesity, and the metabolic syndrome were highlighted as major nutrition-related geriatric syndromes. Great progress has been made in recent years through standardised definitions of some but not all syndromes. Regarding malnutrition, the GLIM approach has shown to be suitable also in older adults, justifying its continuous implementation. For anorexia of ageing, a consensus definition is still required. Intervention approaches should be integrated and person-centered with the aim of optimizing intrinsic capacity and maintaining functional capacity. Landmark studies like EFFORT and FINGER have impressively documented the potential of individualised and multifactorial interventions for functional and health benefits. Combining nutritional intervention with physical training seems particularly important whereas restrictive diets and drug treatment should generally be used with caution because of undesirable risks. Obesity management in older adults should take into account the risk of promoting sarcopenia.

CONCLUSIONS

In the future, even more individualised approaches like precision nutrition may enable better nutritional care. Meanwhile all stakeholders should focus on a better implementation of currently available strategies and work closely together to improve nutritional care for older adults.

Metabolic Syndrome and Positive Frailty Screening: A Cross-Sectional Study with Community-Dwelling Older Adults

Background

Metabolic Syndrome is a set of disorders that characterized by the association of three or more risk factors, like the obesity central, dyslipidemia, borderline blood pressure, hyperglycemia, and the increase of triglycerides. However, these factors also can be associated with pathophysiology of frailty.

Objectives

verifying whether the metabolic syndrome is associated to the positive frailty screening in the older people.

Design

Cross-sectional study. Participants: 443 older people living in Rio Branco, Brazil.

Setting

Data collection was carried out in two stages: a personal interview and blood collection.

Measurements

The diagnosis of metabolic syndrome was based on the criteria of the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults. The frailty screening was performed using subjective questions validated in a previous study. Descriptive statistics and multinomial logistic regression were used for data analyses.

Results

There was a predominance of female older people (69.07%), aged between 60 and 79 years (87.13%), with an income greater than or equal to one minimum wage (72.09%), no cognitive decline (75.94%) and depressive symptoms (63.31%), independent for BADL (86.46%) and dependent for IADL (51.69%). From the total sample, 56.88% of the older people were identified as frail, 34.09% pre-frail and 9.03% non frail. The prevalence of metabolic syndrome was 51.69%. After adjusting by the independent variables, an association between metabolic syndrome and pre-frailty was observed, and older people with metabolic syndrome were more likely to be prefrail (RRR=2.36; 95%CI=1.08-5.18).

Conclusion

The metabolic syndrome was associated to the increase chance of screening for prefrailty in the older people evaluated, which reinforces the needy to establish preventive measures in relation to the metabolic syndrome to avoid frailty in the older people.

The intersection of frailty and metabolism

On average, aging is associated with unfavorable changes in cellular metabolism, which are the processes involved in the storage and expenditure of energy. However, metabolic dysregulation may not occur to the same extent in all older individuals as people age at different rates. Those who are aging rapidly are at increased risk of adverse health outcomes and are said to be "frail." Here, we explore the links between frailty and metabolism, including metabolic contributors and consequences of frailty. We examine how metabolic diseases may modify the degree of frailty in old age and suggest that frailty may predispose toward metabolic disease. Metabolic interventions that can mitigate the degree of frailty in people are reviewed. New treatment strategies developed in animal models that are poised for translation to humans are also considered. We suggest that maintaining a youthful metabolism into older age may be protective against frailty.

Composite dietary antioxidant index is associated with reduced prevalence of metabolic syndrome but not mortality in metabolic syndrome: Results from NHANES 2001-2018

The relationship between the composite dietary antioxidant index (CDAI), a comprehensive measure of individual dietary antioxidants, and the prevalence and mortality of metabolic syndrome (MetS) remains unknown. We aimed to explore these relationships in the National Health and Nutrition Examination Survey (NHANES). We explored these relationships using two independent cohorts. First, we addressed CDAI and the prevalence of MetS in the general population; second, we explored the association between CDAI and mortality in patients with MetS by following NHANES 2001-2018 participants through December 31, 2019. In addition, restricted cubic spline (RCS), stratified analysis, and sensitivity analysis were used for further interpretation. We included 24,514 participants aged 20-85 years, in which the prevalence of MetS was 27.61 %. CDAI was negatively and dose-responsively associated with the prevalence of MetS, however it was not associated with mortality in patients with MetS. In addition, CDAI was associated with a reduced prevalence of certain components of MetS, including dyslipidemia and central obesity. RCS showed a linear correlation between CDAI and MetS and the above components. Stratified analyses indicated that alcohol consumption was a significant influence of CDAI-MetS and that socioeconomic status and lifestyle specificity existed. Sensitivity analysis confirmed the stability of the results. CDAI was protective against the development of MetS in the general population, but not against mortality in patients with MetS. Clinicians need to develop individualized prevention strategies to reduce the development of MetS by modifying CDAI.

Interplay of body mass index and metabolic syndrome: association with physiological age from midlife to late-life

Obesity and metabolic syndrome (MetS) share common pathophysiological characteristics with aging. To better understand their interplay, we examined how body mass index (BMI) and MetS jointly associate with physiological age, and if the associations changed from midlife to late-life. We used longitudinal data from 1,825 Swedish twins. Physiological age was measured as frailty index (FI) and functional aging index (FAI) and modeled independently in linear mixed-effects models adjusted for chronological age, sex, education, and smoking. We assessed curvilinear associations of BMI and chronological age with physiological age, and interactions between BMI, MetS, and chronological age. We found a significant three-way interaction between BMI, MetS, and chronological age on FI (p-interaction = 0·006), not FAI. Consequently, we stratified FI analyses by age: < 65, 65-85, and ≥ 85 years, and modeled FAI across ages. Except for FI at ages ≥ 85, BMI had U-shaped associations with FI and FAI, where BMI around 26-28 kg/m2 was associated with the lowest physiological age. MetS was associated with higher FI and FAI, except for FI at ages < 65, and modified the BMI-FI association at ages 65-85 (p-interaction = 0·02), whereby the association between higher BMI levels and FI was stronger in individuals with MetS. Age modified the MetS-FI association in ages ≥ 85, such that it was stronger at higher ages (p-interaction = 0·01). Low BMI, high BMI, and metabolic syndrome were associated with higher physiological age, contributing to overall health status among older individuals and potentially accelerating aging.

Association between frailty and hepatic fibrosis in NAFLD among middle-aged and older adults: results from NHANES 2017-2020

Background

Although previous studies found that frailty is prevalent in NAFLD patients with advanced liver fibrosis and cirrhosis, studies examining the relationship are spare.

Aim

Our study aspires to investigate the potential correlation between the Frailty Index (FI) and hepatic fibrosis among middle-aged and older adults with NAFLD.

Methods

Data from the 2017-2020.03 National Health and Nutrition Examination Survey (NHANES) were utilized for this study, with a final of 2,383 participants aged 50 years and older included. The quantification of frailty was executed employing a 49-item frailty index. The recognition of hepatic steatosis and fibrosis was accomplished through the utilization of the controlling attenuation parameter (CAP) and transient elastography (TE). The relationship between the FI and hepatic fibrosis were investigated employing univariable and multivariable-adjusted logistic regression analyses. A subgroup analysis was conducted, dividing the subjects based on gender, Body Mass Index (BMI), and the presence of hyperlipidemia.

Results

The findings demonstrated a positive correlation between the FI and significant hepatic fibrosis in NAFLD, even after using multivariate logistic regression models adjusting for potential confounding factors (OR = 1.022, 95% CI, 1.004-1.041) and in tertiles (Q3vs Q1: OR = 2.004, 95% CI, 1.162-3.455). In the subgroup analysis, the correlation was more statistically significant in male (OR = 1.046, 95% CI, 1.022-1.071), under/normal weight (OR = 1.077, 95% CI, 1.009-1.150), overweight (OR = 1.040, 95% CI, 1.010-1.071), and subjects without hyperlipidemia (OR = 1.054, 95% CI, 1.012-1.097). The area under the Receiver Operating Characteristic (ROC) curve for the FI in assessing the existence of substantial fibrosis in NAFLD was 0.612 (95% CI, 0.596-0.628).

Conclusion

This study demonstrated a positive correlation between significant hepatic fibrosis and frailty, particularly among males aged 50 years and older, who were non-obese and did not have hyperlipidemia with NAFLD. Additional studies are required to further validate these findings.

Frailty and Survivability of Polish Caucasian Nonagenarians and Centenarians

Frailty is a major geriatric problem leading to an increased risk of disability and death. Prevention, identification, and treatment of frailty are important challenges in gerontology and public health. The study aimed to estimate the prevalence of the frailty phenotype (FP) among the oldest-old Polish Caucasians and investigate the relationship between the FP and mortality. Baseline data were collected from 289 long-lived individuals, including 87 centenarians and 202 subjects aged 94-99. Mortality was obtained from population registers over the following 5 years. Sixty percent of subjects were classified as frail, 33% as prefrail, and 7% as robust. Frailty was more common in women than men and among centenarians than nonagenarians. During the 5-year observation period, 92.6% of the frail women and all frail men died, while mortality rates were lower among prefrail, 78.8% and 66.7%, and robust individuals, 60% and 54.5%, respectively. In the survival analysis, frailty was the strongest negative risk factor: HR = 0.328 (95% CI: 0.200-0.539). The inability to perform handgrip strength measurement was an additional predictor of short survival. In conclusion, the FP is prevalent in nonagenarians and centenarians and correlates with lower survivability. Future studies should address differences between unavoidable age-associated frailty and reversible disability in long-lived individuals.

Phenotypic Frailty Assessment in SAMP8 Mice: Sex Differences and Potential Role of miRNAs as Peripheral Biomarkers

Frailty is a geriatric syndrome characterized by age-related decline in physiological reserves and functions in multiple organ systems, including the musculoskeletal, neuroendocrine/metabolic, and immune systems. Animal models are essential to study the biological basis of aging and potential ways to delay the onset of age-related phenotypes. Unfortunately, validated animal models of frailty are still lacking in preclinical research. The senescence-accelerated prone-8 (SAMP8) mouse strain exhibits early cognitive loss that mimics the deterioration of learning and memory in the elderly and is widely used as a model of aging and neurodegenerative diseases. Here, we examined the frailty phenotype, which includes body weight, strength, endurance, activity, and slow walking speed, in male and female SAMP8 and senescence-accelerated mouse resistant (SAMR1) mice at 6- and 9-months of age. We found that the prevalence of frailty was higher in SAMP8 mice compared with SAMR1 mice, regardless of sex. The overall percentage of prefrail and frail mice was similar in male and female SAMP8 mice, although the percentage of frail mice was slightly higher in males than in females. In addition, we found sex- and frailty-specific changes in selected miRNAs blood levels. In particular, the levels of miR-34a-5p and miR-331-3p were higher in both prefrail and frail mice, whereas miR-26b-5p was increased only in frail mice compared with robust mice. Finally, levels of miR-331-3p were also increased in whole blood from a small group of frail patients. Overall, these results suggest that SAMP8 mice may be a useful mouse model for identifying potential biomarkers and studying biological mechanisms of frailty.

Supplementation with okra combined or not with exercise training is able to protect the heart of animals with metabolic syndrome

The metabolic syndrome (MetS) is a clinical manifestation strongly associated with cardiovascular disease, the main cause of death worldwide. In view of this scenario, many therapeutic proposals have appeared in order to optimize the treatment of individuals with MetS, including the practice of exercise training (ET) and the consumption of okra (O). The aim of the present study was to evaluate the effect of O consumption and/or ET in animals with MetS. In all, 32 male Zucker rats (fa/fa) at 10 weeks old were randomly distributed into four groups of 8 animals each: MetS, MetS+O, MetS+ET and MetS+ET+O, and 8 lean Zucker rats (fa/ +) comprised the control group. Okra was administered by orogastric gavage 2x/day (morning and night, 100 mg/kg), 5 days/week, for 6 weeks. The ET was performed on a treadmill 1x/day (afternoon), 5 days/week, 60 min/day, in an intensity of 70% of maximal capacity, for the same days of O treatment. It was found that, O consumption alone was able to promote improved insulin sensitivity (MetS 93.93 ± 8.54 mg/dL vs. MetS+O 69.95 ± 18.7 mg/dL, p ≤ 0.05, d = 1.65, CI = 50.32 -89.58, triglyceride reduction (MetS 492.9 ± 97.8 mg/dL vs. MetS+O 334.9 ± 98.0 mg/dL, p ≤ 0.05, d = 1.61, CI = 193.2-398.7). In addition, it promoted a reduction in systolic blood pressure (MetS 149.0 ± 9.3 mmHg vs. MetS+O 132.0 ± 11.4 mmHg, p ≤ 0.05, d = 1.63, CI = 120-140), prevented an increase in cardiac collagen (MetS 12.60 ± 2.08% vs. MetS+O 7.52 ± 0.77%, p ≤ 0.05, d = 3.24, CI = 6.56-8.49). When associated with ET, the results were similar. Thus, we conclude that O consumption combined or not with aerobic ET can have a protective effect on the cardiac tissue of rats with MetS.

The Association between Metabolic Syndrome, Frailty and Disability-Free Survival in Healthy Community-dwelling Older Adults

OBJECTIVES

To examine the association between metabolic syndrome (MetS) and frailty, and determine whether co-existent MetS and frailty affect disability-free survival (DFS), assessed through a composite of death, dementia or physical disability.

DESIGN

Longitudinal study.

SETTING AND PARTICIPANTS

Community-dwelling older adults from Australia and the United States (n=18,264) from "ASPirin in Reducing Events in the Elderly" (ASPREE) study.

MEASUREMENTS

MetS was defined according to American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines (2018). A modified Fried phenotype and a deficit accumulation Frailty Index (FI) were used to assess frailty. Association between MetS and frailty was examined using multinomial logistic regression. Cox regression was used to analyze the association between MetS, frailty and DFS over a median follow-up of 4.7 years.

RESULTS

Among 18,264 participants, 49.9% met the criteria for MetS at baseline. Participants with Mets were more likely to be pre-frail [Relative Risk Ratio (RRR): 1.22; 95%Confidence Interval (CI): 1.14, 1.30)] or frail (RRR: 1.66; 95%CI: 1.32, 2.08) than those without MetS. MetS alone did not shorten DFS while pre-frailty or frailty alone did [Hazard Ratio (HR): 1.68; 95%CI: 1.45, 1.94; HR: 2.65; 95%CI:1.92, 3.66, respectively]. Co-existent MetS with pre-frailty/frailty did not change the risk of shortened DFS.

CONCLUSIONS

MetS was associated with pre-frailty or frailty in community-dwelling older individuals. Pre-frailty or frailty increased the risk of reduced DFS but presence of MetS did not change this risk. Assessment of frailty may be more important than MetS in predicting survival free of dementia or physical disability.

Frailty and risk of cardiovascular disease and mortality

Background

Prospective cohort studies suggest that frailty is associated with an increased risk of incident cardiovascular disease (CVD) morbidity and mortality, but their mechanistic and developmental relations are not fully understood. We investigated whether frailty predicted an increased risk of incident nonfatal and fatal CVD among community-dwelling older adults.

Methods

A population cohort of 5015 participants aged 55 years and above free of CVD at baseline was followed for up to 10 years. Pre-frailty and frailty were defined as the presence of 1–2 and 3–5 modified Fried criteria (unintentional weight loss, weakness, slow gait speed, exhaustion, and low physical activity), incident CVD events as newly diagnosed registered cases of myocardial infarction (MI), stroke, and CVD-related mortality (ICD 9: 390 to 459 or ICD-10: I00 to I99). Covariate measures included traditional cardio-metabolic and vascular risk factors, medication therapies, Geriatric Depression Scale (GDS), Mini-Mental State Exam (MMSE), and blood biomarkers (haemoglobin, albumin, white blood cell counts and creatinine).

Results

Pre-frailty and frailty were significantly associated with elevated HR = 1.26 (95%CI: 1.02–1.56) and HR = 1.54 (95%CI:1.00–2.35) of overall CVD, adjusted for cardio-metabolic and vascular risk factors and medication therapies, but not after adjustment for GDS depression and MMSE cognitive impairment. The HR of association between frailty status and both CVD mortality and overall mortality, however, remained significantly elevated after full adjustment for depression, cognitive and blood biomarkers.

Conclusion

Frailty was associated with increased risk of CVD morbidity and especially mortality, mediated in parts by traditional cardio-metabolic and vascular risk factors, and co-morbid depression and associated cognitive impairment and chronic inflammation. Given that pre-frailty and frailty are reversible by multi-domain lifestyle and health interventions, there is potential benefits in reducing cardiovascular diseases burden and mortality from interventions targeting pre-frailty and early frailty population.

The association between metabolic syndrome and presence of frailty: a systematic review and meta-analysis

BACKGROUND

Frailty represents a progressive deterioration in multi-system of the body and could increase vulnerability to stressors. Recently, several studies found that metabolic syndrome was significantly associated with frailty and emphasized its role in assessing and preventing frailty. However, these conclusions are controversial. We conducted this systematic review and meta-analysis to evaluate the association between metabolic syndrome and frailty.

METHODS

Databases including Pubmed, Embase, Web of Science, CINAHL Complete, China National Knowledge Infrastructure (CNKI) and Wanfang Data Knowledge Service Platform were searched for studies on the association between metabolic syndrome and frailty, from inception to 17th June 2022. Two researchers independently screened the literature, extracted the data and evaluated the quality. Stata/SE 15.0 software was used to perform the statistical analysis.

RESULTS

Eleven studies were included in this review and eight studies were included in the meta-analysis, involving one prospective cohort studies and ten cross-sectional studies with 12,640 participants. The pooled results indicated that metabolic syndrome was significantly associated with frailty (OR = 1.82, 95% CI = 1.46-2.27) with a low heterogeneity (I² = 32.1%), and there were significant associations between MetS and weakness (OR = 1.35, 95% CI = 1.15-1.58, I² = 0.0%), slow gait speed (OR = 1.80, 95% CI = 1.51-2.14, I² = 93.4%), weight loss (OR = 1.77, 95% CI = 1.36-2.29, I² = 0.0%) and decreased physical activity (OR = 1.87, 95% CI = 1.49-2.35, I² = 39.7%).

CONCLUSIONS

The findings of this systematic review and meta-analysis suggested that metabolic syndrome could be significantly associated with the presence of frailly. Future studies need to further consider the effects of measurement tools, age and specific disease status in this association. Furthermore, the casual relationship between them is to be determined.

The Relationship between Metabolic Syndrome and Frailty in Older People: A Systematic Review and Meta-Analysis

Aims: Both metabolic syndrome (MetS) and frailty are associated with increased all-cause mortality, yet the complex interplay between these two conditions has not adequately been elucidated. We aim to analyse the relationship between MetS and frailty through a systematic review of the literature with meta-analyses. Methods: A literature search was conducted via MEDLINE and EMBASE. Studies were included if validated frameworks for defining frailty and MetS (presence of at least 3 out of the five constitutive components: abdominal obesity, high fasting blood glucose, hypertension, hypertriglyceridaemia, and low high-density lipoprotein level) were utilised, in addition to the inclusion of participants aged 60 or older. Results: Eleven studies were included, all observational. All were in community-dwelling older people, 9 cross-sectional and 2 longitudinal. Most of the studies used Fried’s frailty phenotype. The prevalence of frailty ranged from 0.9% to 14.8% in population-based studies and 35.6% in the outpatient clinic setting. The prevalence of MetS was also higher in the outpatient clinic setting at 47.5%, compared to 17.5–41.0% in the community-dwelling populations. The meta-analysis of 11 studies showed that MetS was associated with an increased risk of frailty (pooled OR 1.73, 95% CI, 1.41–2.13). Conclusion: This systematic review and meta-analysis suggest that frailty was more prevalent in older people with MetS compared to older people without MetS. The study findings suggest the importance of frailty screening in older people with MetS and a distinct role of managing MetS in preventing frailty in older people.

Undercarboxylated Osteocalcin: A Promising Target for Early Diagnosis of Cardiovascular and Glycemic Disorders in Patients with Metabolic Syndrome: A Pilot Study

Lifestyle changes are causing an exponential increase in the prevalence of obesity and metabolic syndrome (MetS) worldwide. The most frequent complications of these are the development of diabetes (T2D) and cardiovascular disease (CVD). Accurate tools are needed to classify the cardiovascular risk (CVR) in the MetS population. In recent years, numerous biomarkers of bone metabolism have been associated with CVR. The aim of this study was to determine the levels of undercarboxylated osteocalcin (ucOC) in a cohort of patients with MetS and to analyse its association with MetS parameters and CVR as well as with T2D prevalence. A longitudinal study was conducted in which a MetS population was followed for one year. Weight change, adherence to the Mediterranean diet (MedDiet), ucOC levels, MetS parameters and CVR were analysed and CVR was calculated using different scores. Our results showed a decrease of CVR associated with a better adherence to the MetDiet resulting in higher HDL-C and ucOC levels though the improvement of MetS risk factors. This bone protein appeared as a potential biomarker to classify CVR in the MetS population, especially for MetS patients without prevalent T2D. Furthermore, ucOC serum levels could be good predictors of T2D prevalence.

Frailty is independently associated with worse outcomes and increased resource utilization following endometrial cancer surgery

OBJECTIVE

Frailty has been associated with poorer surgical outcomes and is a critical factor in procedural risk assessment. The objective of this study is to assess the impact of frailty on surgical outcomes in patients with endometrial cancer.

METHODS

Patients undergoing inpatient gynecologic surgery for endometrial cancer were identified using the 2005-2017 Nationwide Inpatient Sample database. The Johns Hopkins Adjusted Clinical Groups frailty-defining diagnosis indicator was used to designate frailty. Multivariate regression models were used to assess the association of frailty with postoperative outcomes and resource use.

RESULTS

Of 339 846 patients, 2.9% (9868) were considered frail. After adjusting for patient and hospital characteristics, frailty was associated with a four-fold increase in inpatient mortality (adjusted OR (aOR) 4.1; p<0.001), non-home discharge (aOR 5.2; p<0.001), as well as increased respiratory (aOR 2.6; p<0.001), neurologic (aOR 3.3; p<0.001), renal (aOR 2.0; p<0.001), and infectious (aOR 3.2; p<0.001) complications. While frail patients exhibited increased mortality with age, the rate of mortality in this cohort decreased significantly over time. Compared with non-frail counterparts, frail patients had longer lengths of stay (7.6 vs 3.4 days; p<0.001) and increased hospitalization costs with surgical admission ($25 093 vs $13 405; p<0.001).

CONCLUSIONS

Frailty is independently associated with worse surgical outcomes, including increased mortality and resource use, in women undergoing surgery for endometrial cancer. Though in recent years there have been improvements in mortality in the frail population, further efforts to mitigate the impact of frailty should be explored.

Physiological Systems in Promoting Frailty

Frailty is a complex syndrome affecting a growing sector of the global population as medical developments have advanced human mortality rates across the world. Our current understanding of frailty is derived from studies conducted in the laboratory as well as the clinic, which have generated largely phenotypic information. Far fewer studies have uncovered biological underpinnings driving the onset and progression of frailty, but the stage is set to advance the field with preclinical and clinical assessment tools, multiomics approaches together with physiological and biochemical methodologies. In this article, we provide comprehensive coverage of topics regarding frailty assessment, preclinical models, interventions, and challenges as well as clinical frameworks and prevalence. We also identify central biological mechanisms that may be at play including mitochondrial dysfunction, epigenetic alterations, and oxidative stress that in turn, affect metabolism, stress responses, and endocrine and neuromuscular systems. We review the role of metabolic syndrome, insulin resistance and visceral obesity, focusing on glucose homeostasis, adenosine monophosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and nicotinamide adenine dinucleotide (NAD⁺ ) as critical players influencing the age-related loss of health. We further focus on how immunometabolic dysfunction associates with oxidative stress in promoting sarcopenia, a key contributor to slowness, weakness, and fatigue. We explore the biological mechanisms involved in stem cell exhaustion that affect regeneration and may contribute to the frailty-associated decline in resilience and adaptation to stress. Together, an overview of the interplay of aging biology with genetic, lifestyle, and environmental factors that contribute to frailty, as well as potential therapeutic targets to lower risk and slow the progression of ongoing disease is covered. © 2022 American Physiological Society. Compr Physiol 12:1-46, 2022.

Independent and joint effects of body mass index and metabolic health in mid- and late-life on all-cause mortality: a cohort study from the Swedish Twin Registry with a mean follow-up of 13 Years

BACKGROUND

There is robust evidence that in midlife, higher body mass index (BMI) and metabolic syndrome (MetS), which often co-exist, are associated with increased mortality risk. However, late-life findings are inconclusive, and few studies have examined how metabolic health status (MHS) affects the BMI-mortality association in different age categories. We, therefore, aimed to investigate how mid- and late-life BMI and MHS interact to affect the risk of mortality.

METHODS

This cohort study included 12,467 participants from the Swedish Twin Registry, with height, weight, and MHS measures from 1958-2008 and mortality data linked through 2020. We applied Cox proportional hazard regression with age as a timescale to examine how BMI categories (normal weight, overweight, obesity) and MHS (identification of MetS determined by presence/absence of hypertension, hyperglycemia, low HDL, hypertriglyceridemia), independently and in interaction, are associated with the risk of all-cause mortality. Models were adjusted for sex, education, smoking, and cardiovascular disease.

RESULTS

The midlife group included 6,252 participants with a mean age of 59.6 years (range = 44.9-65.0) and 44.1% women. The late-life group included 6,215 participants with mean age 73.1 years (65.1-95.3) and 46.6% women. In independent effect models, metabolically unhealthy status in midlife increased mortality risks by 31% [hazard ratio 1.31; 95% confidence interval 1.12-1.53] and in late-life, by 18% (1.18;1.10-1.26) relative to metabolically healthy individuals. Midlife obesity increased the mortality risks by 30% (1.30;1.06-1.60) and late-life obesity by 15% (1.15; 1.04-1.27) relative to normal weight. In joint models, the BMI estimates were attenuated while those of MHS were less affected. Models including BMI-MHS categories revealed that, compared to metabolically healthy normal weight, the metabolically unhealthy obesity group had increased mortality risks by 53% (1.53;1.19-1.96) in midlife, and across all BMI categories in late-life (normal weight 1.12; 1.01-1.25, overweight 1.10;1.01-1.21, obesity 1.31;1.15-1.49). Mortality risk was decreased by 9% (0.91; 0.83-0.99) among those with metabolically healthy overweight in late-life.

CONCLUSIONS

MHS strongly influenced the BMI-mortality association, such that individuals who were metabolically healthy with overweight or obesity in mid- or late-life did not carry excess risks of mortality. Being metabolically unhealthy had a higher risk of mortality independent of their BMI.

Frailty Index in the Colonias on the US-Mexico Border: A Special Report

Frailty is the age-related decline in well-being. The Frailty index (FI) measures the accumulation of health deficits and reflects biopsychosocial and cultural determinants of well-being. Frailty is measured as a static phenotype or as a Frailty Index comprising a ratio of suffered health deficits and total deficits. We report a Frailty Index calculated from routinely measured clinical variables gathered from residents of two Colonias (neighborhoods) in South Texas. A Colonia is a predominantly Hispanic, economically distressed, unincorporated neighborhood. We analyzed retrospective data from 894 patients that live in two Colonias located on the Texas-Mexico border. We calculated the FI with seven physiological variables, PHQ-9 score, and the 11 domain-specific Duke Profile scores, for a total of 19 possible health deficits. FI against age separately in males (n = 272) and females (n = 622) was regressed. Females had a significantly higher starting frailty, and males had a significantly greater change rate with age. FI against age for Cameron Park Colonia and Indian Hills Colonia was regressed. We calculated a significantly higher starting FI in Indian Hills and a significantly greater change rate in Cameron Park residents. Frailty's contributors are complex, especially in neighborhoods of poverty, immigration, low education level, and high prevalence of chronic disease. We report baseline Frailty Index data from two Colonias in South Texas and the clinical and research implications.

Association between serum lactate dehydrogenase and frailty among individuals with metabolic syndrome

While metabolic syndrome (MetS) is associated with frailty, the correlation of serum lactate dehydrogenase (sLDH) and frailty with MetS remain uncertain. To investigate the relationship between sLDH and frail components in the US with MetS. A total of 4,066 participants aged 40-90 years were assessed from the database of the third National Health and Nutrition Examination Survey, 1988-1994. The participants were classified into MetS and non-MetS groups. Multivariate logistic regression analysis with four models were performed to assess the odds ratio (OR) of the divided tertiles of sLDH levels with frailty, and frail components including slow walking (SW), weakness, exhaustion, low physical activity (LPA), and low body weight (LBW). Higher sLDH levels were positively associated with frailty in the MetS group (p = 0.024) but not in non-MetS group (p = 0.102). After covariate adjustments, the OR of frailty in the upper two tertiles compared to the lowest tertile and revealed statistical significance (p < 0.05). Frail components of SW, weakness, exhaustion, and LPA were associated with higher sLDH (p < 0.05) except for LBW in MetS and non-MetS groups. The results demonstrated the strong association of higher sLDH levels and frailty among US individuals with MetS.

Metabolically Unhealthy Phenotype: A Key Factor in Determining "Pediatric" Frailty

Frailty (FI) and metabolic syndrome (MS) are each associated with adverse health outcomes. A relationship between FI and MS has previously been described in adults. We considered the prevalence of a metabolically unhealthy phenotype (MUP) in malnourished children with neurological impairment and in subjects with obesity in comparison to a group of elderly individuals at risk of FI, and we did so in order to define the potential similarities that may underline the risk of FI in specific children. We considered 50 undernourished (defined as having a body mass index of BMI ≤ 2, standard deviation score, SDS, according to World Health Organization) disabled children; 50 children with obesity (BMI ≥ 2 SDS); 50 children who were a normal weight (-1 SDS ≤ BMI ≤ +1 SDS); 21 patients who were >75 years old. MUP was defined as the presence of at least one of the following risk factors: hypertension, hyperglycemia or diabetes, hypercholesterolemia, and hypertriglyceridemia. In children with a disability and obesity, a higher prevalence (p < 0.001) and risk (disability OR 54.88, obesity OR 13.37) of MUP was noted compared to children of a normal weight. Compared to elderly patients, the prevalence of MUP did not differ in disabled children. On the contrary, MUP was lower in children with obesity (p < 0.001) and in pediatric subjects of a normal weight (p < 0.01). MS might play a key role in "pediatric" frailty. The extremities of the aging process and malnutrition are likely key factors in the development of FI. A multidisciplinary approach to FI may represent an important milestone for pediatric care.

Dual effects of insulin resistance on mortality and function in non-diabetic older adults: findings from the Toledo Study of Healthy Aging

Insulin signalling declines with increasing age and impacts skeletal muscle function and longevity in animal models. Our aim was to assess the relationships between insulin resistance (IR) and frailty and mortality in a unique community-dwelling cohort of older people. 991 non-diabetic subjects from the Toledo Study of Healthy Ageing (TSHA) cohort were included. IR was estimated by the homeostasis model assessment index (HOMA-IR) at baseline while frailty was determined by frailty phenotype (FP) and Frailty Trait Scale (FTS) at baseline and after 5-year follow-up. Deaths were also determined. Multivariate regression models were used to analyze the effects of HOMA-IR on outcomes. Age, gender, BMI, education level, cardio- and cerebro-vascular disease, glomerular filtration rate, and disability were included as potential confounding variables in progressive adjustment models. IR determined as increasing log HOMA-IR was inversely associated with risk of mortality. The association remained significant for all adjustment models (HR: 0.64-0.69). When we analyzed survival curves, the higher the HOMA-IR tertile, the lower the mortality rate (highest vs lowest tertile, p = 0.0082). In contrast, IR increased the risk of incident frailty determined by FP (OR 1.81 [1.14-2.87]) as well as deterioration of frailty status determined by worsening in FTS score (OR 1.28 [1.01-1.63]) at 5-year follow-up. In non-diabetic older subjects, IR significantly increases the risk for frailty and functional decline but decreased the risk of death at 5-year follow-up. This finding raises the need of assessing the effect of biomarkers on different outcomes before establishing their role as biomarkers of aging.

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.

Measuring frailty in younger populations: a rapid review of evidence

OBJECTIVES

Frailty is typically assessed in older populations. Identifying frailty in adults aged under 60 years may also have value, if it supports the delivery of timely care. We sought to identify how frailty is measured in younger populations, including evidence of the impact on patient outcomes and care.

DESIGN

A rapid review of primary studies was conducted.

DATA SOURCES

Four databases, three sources of grey literature and reference lists of systematic reviews were searched in March 2020.

ELIGIBILITY CRITERIA

Eligible studies measured frailty in populations aged under 60 years using experimental or observational designs, published after 2000 in English.

DATA EXTRACTION AND SYNTHESIS

Records were screened against review criteria. Study data were extracted with 20% of records checked for accuracy by a second researcher. Data were synthesised using a narrative approach.

RESULTS

We identified 268 studies that measured frailty in samples that included people aged under 60 years. Of these, 85 studies reported evidence about measure validity. No measures were identified that were designed and validated to identify frailty exclusively in younger groups. However, in populations that included people aged over and under 60 years, cumulative deficit frailty indices, phenotype measures, the FRAIL Scale, the Liver Frailty Index and the Short Physical Performance Battery all demonstrated predictive validity for mortality and/or hospital admission. Evidence of criterion validity was rare. The extent to which measures possess validity across the younger adult age (18-59 years) spectrum was unclear. There was no evidence about the impact of measuring frailty in younger populations on patient outcomes and care.

CONCLUSIONS

Limited evidence suggests that frailty measures have predictive validity in younger populations. Further research is needed to clarify the validity of measures across the adult age spectrum, and explore the utility of measuring frailty in younger groups.

Impact of Multidomain Lifestyle Intervention on Frailty Through the Lens of Deficit Accumulation in Adults with Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes and obesity increase the accumulation of health deficits and may accelerate biological aging. Multidomain lifestyle interventions may mitigate against this.

METHODS

Within a large, randomized clinical trial of intensive lifestyle intervention including caloric restriction, increased physical activity, dietary counseling, and risk factor monitoring compared with diabetes support and education, we examined the accumulation of health deficits across 8 years. We used two complementary frailty indices (FIs) based on deficit accumulation, one modeled on work in the Systolic Blood Pressure Intervention Trial and the other including additional deficits related to obesity and type 2 diabetes mellitus. Differences between intervention groups and their consistency among subgroups were assessed with re-randomization tests.

RESULTS

Data from 4,859 adults (45-76 years at baseline, 59% female) were analyzed. Random assignment to intensive lifestyle intervention was associated with lower FI scores throughout follow-up as captured by areas under curves traced by longitudinal means (p ≤ .001), over which time mean (SE) differences between intervention groups averaged 5.8% (0.9%) and 5.4% (0.9%) for the two indices. At year 8, the percentage of participants classified as frail (FI > 0.21) was lower among intensive lifestyle intervention (39.8% and 54.5%) compared with diabetes support and education (42.7% and 60.9%) for both FIs (both p < .001). Intervention benefits were relatively greater for participants who were older, not obese, and without history of cardiovascular disease at baseline.

CONCLUSIONS

Eight years of multidomain lifestyle intervention create a buffer against the accumulation of age-related health deficits in overweight or obese adults with type 2 diabetes.ClinicalTrials.gov Identifier: NCT00017953.

Physical Frailty, Multimorbidity, and All-Cause Mortality in an Older Population From Southern Italy: Results from the Salus in Apulia Study

OBJECTIVES

We first estimated the prevalence of physical frailty in older subjects from the population-based Salus in Apulia Study (Apulia, Southern Italy), and its impact on all-cause mortality. Second, we explored the relationship between multimorbidity and physical frailty.

DESIGN

Cross-sectional and longitudinal analyses from a population-based study.

SETTING AND PARTICIPANTS

We analyzed data from the Salus in Apulia study, a population-based sample of 1929 subjects aged 65 years and older.

METHODS

These older participants underwent clinical, physical, and laboratory assessments. Physical frailty was operationalized using slightly modified Fried criteria. Multimorbidity status was defined as the co-presence of 2 or more chronic conditions.

RESULTS

The overall prevalence of physical frailty in this older population from Southern Italy was 14.8% [95% confidence interval (CI): 13.26-16.49]. Physical frailty subjects were significantly older (P < .01), had a lower educational level (P < .01), increased executive dysfunction (P < .01), higher serum levels interleukin-6 (P < .01), and white blood cells (P = .01). Multimorbidity status (P < .01), diabetes mellitus (P = .05), peripheral age-related hearing loss (P < .01), cognitive impairment (P < .01), chronic obstructive pulmonary disease (P = .02), and metabolic syndrome (P = .02) were also directly related to physical frailty. Apathy increased according to the severity of physical frailty status (P = .02). There was a significant increased risk of all-cause mortality for physical frailty subjects (hazard ratio: 1.48; 95% CI: 1.03-2.12, adjusted for age and sex) during the observation from the date of enrollment to the date of death (mean ± SD: 55.70 ± 22.19 months, median: 54 months).

CONCLUSIONS AND IMPLICATIONS

Frailty is the consequence of the contributory action of the aging process and some chronic diseases that hasten some of the changes concurrent with aging.

Frailty and Quality of Life in Older Adults with Metabolic Syndrome - Findings from the Healthy Older People Everyday (HOPE) Study

OBJECTIVES

Metabolic syndrome (MetS) and frailty are both associated with increased morbidity and mortality. Frailty is associated with reduced quality of life (QoL) but association of QoL with MetS have produced mixed results suggesting that other factors such as disease burden, obesity and depression may have a more significant influence. We aim to investigate the demographics of frail participants with MetS, and relationship between frailty and QoL in MetS.

METHODS

Cross-sectional population study involving 292 older adults ≥ 65 years with MetS. MetS was defined using the Modified ATP III for Asians which requires the presence of 3 or more of the following 5 components 1) waist circumference ≥ 90cm for males or ≥ 80cm for females, 2) TG ≥ 150mg/dL, 3) HDLc < 40mg/dL in males or < 50mg/dL in females, 4) blood pressure ≥ 130/85mmHg or use of anti-hypertensive medication, and 5) fasting plasma glucose ≥ 100mg/dL or use of pharmacological treatment for diabetes mellitus. Data were collected on demographics, frailty (FRAIL), QoL (Euroqol-5D), perceived health, functional status, cognition, Timed-Up-and-Go (TUG), and hand-grip strength (HGS).

RESULTS

40.4% of the participants were pre-frail (MetSprefrail) and 7.2% were frail (MetSfrail). MetSfrail were significantly older, had lower education level, higher polypharmacy burden and higher prevalence of diabetes. The prevalence of at least 1 activity of daily living impairment was 4 times higher, and depression 9 times higher than their robust counterparts. MetSfrail also had longer TUG, higher prevalence of poor grip strength and poor perceived health. After adjusting for age, gender and education, MetSfrail was significantly associated with much higher odds of EQ-5D moderate to extreme problems with mobility (Odds Ratio (OR) =10.99, CI 2.62-46.14), usual activities (OR=37.82, CI 3.77-379.04) and pain (OR=10.79, CI 3.18-36.62). EQ-5D Index Value and Perceived Health improved by 0.1 (Mean Difference (MD) =0.07, CI 0.04-0.10) and 6.0 (MD=6.01, CI 3.29-8.73) respectively as frailty status improved.

CONCLUSION

Frailty in MetS is associated with depression, polypharmacy, greater functional impairment, poorer QoL and perceived health. Frailty screening and personalized management is crucial in MetS as frailty may be a mediator for negative outcomes in MetS, and frailty may be reversible.

Age and life expectancy clocks based on machine learning analysis of mouse frailty

The identification of genes and interventions that slow or reverse aging is hampered by the lack of non-invasive metrics that can predict the life expectancy of pre-clinical models. Frailty Indices (FIs) in mice are composite measures of health that are cost-effective and non-invasive, but whether they can accurately predict health and lifespan is not known. Here, mouse FIs are scored longitudinally until death and machine learning is employed to develop two clocks. A random forest regression is trained on FI components for chronological age to generate the FRIGHT (Frailty Inferred Geriatric Health Timeline) clock, a strong predictor of chronological age. A second model is trained on remaining lifespan to generate the AFRAID (Analysis of Frailty and Death) clock, which accurately predicts life expectancy and the efficacy of a lifespan-extending intervention up to a year in advance. Adoption of these clocks should accelerate the identification of longevity genes and aging interventions.

Physical activity and exercise: Strategies to manage frailty

Frailty, a consequence of the interaction of the aging process and certain chronic diseases, compromises functional outcomes in the elderly and substantially increases their risk for developing disabilities and other adverse outcomes. Frailty follows from the combination of several impaired physiological mechanisms affecting multiple organs and systems. And, though frailty and sarcopenia are related, they are two different conditions. Thus, strategies to preserve or improve functional status should consider systemic function in addition to muscle conditioning. Physical activity/exercise is considered one of the main strategies to counteract frailty-related physical impairment in the elderly. Exercise reduces age-related oxidative damage and chronic inflammation, increases autophagy, and improves mitochondrial function, myokine profile, insulin-like growth factor-1 (IGF-1) signaling pathway, and insulin sensitivity. Exercise interventions target resistance (strength and power), aerobic, balance, and flexibility work. Each type improves different aspects of physical functioning, though they could be combined according to need and prescribed as a multicomponent intervention. Therefore, exercise intervention programs should be prescribed based on an individual's physical functioning and adapted to the ensuing response.

Comorbidities in Older Persons with Controlled HIV Infection: Correlations with Frailty Index Subtypes

Frailty is prevalent in persons with human immunodeficiency virus (PWH), but factors predisposing older PWH to frailty remain uncertain. We examined factors associated with frailty and determined whether there were multiple frailty subtypes in older adults with controlled HIV infection. This was a cross-sectional outpatient study in an urban HIV clinic. Twenty-nine clinical indicators were extracted from medical records to compute a Frailty Index (FI) for 389 older (age 50+) PWH (range = 50-93; mean = 61.1, standard deviation = 7.2; 85% men) receiving HIV treatment in Calgary, Canada. We used regressions to identify factors associated with FI values. Latent class analysis was used to identify FI subtypes. Age, employment status, and duration of known HIV infection were the strongest predictors of FI (p's < 0.05). Four FI subtypes were identified. Subtype 1 (severe metabolic dysfunction+polypharmacy) had the highest mean FI (0.30). Subtype 2 (less severe metabolic dysfunction+polypharmacy) and Subtype 3 (lung and liver dysfunction+polypharmacy) had lower but equivalent mean FIs (0.20 for each). Subtype 4 (least severe metabolic dysfunction) had the lowest mean FI (0.13; p's < 0.001). Sociodemographic and behavioral characteristics differed among the subtypes. Individuals with Subtype 1 were older and more frequently unemployed/retired, whereas those with Subtype 3 were more likely to smoke, use crack/cocaine, have heavy alcohol use, and live in temporary/unstable housing. The clinical presentation of frailty in older PWH is heterogeneous. The metabolic syndrome, hepatitis C virus coinfection, cirrhosis, lung disease, and polypharmacy were associated with frailty as were unemployment/retirement, unstable housing, and substance use.

Methionine restriction delays aging-related urogenital diseases in male Fischer 344 rats

Dietary methionine restriction (MR) has been found to enhance longevity across many species. We hypothesized that MR might enhance longevity in part by delaying or inhibiting age-related disease processes. To this end, male Fischer 344 rats were fed control (CF, 0.86% methionine) or MR (0.17% methionine) diets throughout their life until sacrifice at approximately 30 months of age, and histopathology was performed to identify the incidence and progression of two important aging-related pathologies, namely, chronic progressive nephropathy (CPN) and testicular tumorigenesis. Although kidney pathology was observed in 87% CF rats and CPN in 62% of CF animals, no evidence of kidney disease was observed in MR rats. Consistent with the absence of renal pathology, urinary albumin levels were lower in the MR group compared to controls throughout the study, with over a six-fold difference between the groups at 30 months of age. Biomarkers associated with renal disease, namely, clusterin, cystatin C, and β-2 microglobulin, were reduced following 18 months of MR. A reduction in testicular tumor incidence from 88% in CF to 22% in MR rats was also observed. These results suggest that MR may lead to metabolic and cellular changes providing protection against age-related diseases.

Advanced Age and Chronic Kidney Disease Modify the Association Between Metabolic Syndrome and Frailty Among Community-Dwelling Elderly

Metabolic syndrome (MetS) predisposes older adults to the development of frailty. However, previous studies have not explored factors that may influence the association between MetS and the risk of frailty in this population. Community-dwelling older adults (≥65 years of age) were prospectively identified and enrolled between 2013 and 2016. MetS and frailty were defined based on the American Association of Clinical Endocrinologists and Study of Osteoporotic Fractures criteria, respectively. Multiple logistic regression with frailty/prefrailty as the dependent variable was used to examine the relationship between MetS and frailty/prefrailty, supplemented by subgroup analyses of the influence of aging and chronic kidney disease (CKD). Among 2862 elderly (73.4 ± 6.7 years), 17.5% and 17.3%, respectively, had MetS and frailty/prefrailty, among whom 74 (2.6%) and 420 (14.7%) had frailty and prefrailty. The presence of MetS (odds ratio [OR] 2.53, p < 0.001), higher age (OR 1.05, p < 0.001), and CKD (OR 1.42, p = 0.006) were associated with a significantly higher risk of frailty/prefrailty. Furthermore, among those ≥80 years of age, the association between MetS and frailty/prefrailty disappeared (p = 0.329). Among those with CKD, the presence of MetS was significantly associated with a progressively higher risk of frailty/prefrailty (for stage 3 or higher and for stage 3b or higher, OR 6.4 and 12.4, p < 0.001 and = 0.009, respectively). In conclusion, aging and CKD modified the association between MetS and frailty. These findings may assist in devising case-specific care plans for elderly with MetS by refocusing our attention on those at high risk of developing frailty/prefrailty.

Evaluation of the pharmacokinetics of metformin and acarbose in the common marmoset

Metformin has beneficial effects on several age-related diseases (e.g., diabetes, obesity, cancer) and extends lifespan in nematodes and mice. Acarbose, an FDA-approved agent for treating type 2 diabetes, prevents breakdown of complex carbohydrates. Both compounds have been suggested as potential anti-aging interventions and acarbose has been shown to extend mouse longevity by the Intervention Testing Program (ITP). One potential next step is to assess the effect of these interventions on healthspan and lifespan in non-human primates. The common marmoset (Callithrix jacchus) is a small new world monkey with a relatively short life span and small size, both valuable for the translation potential of this nonhuman primate species for the study of aging and chronic disease. However, the dosing and assessment of potential side effects of either metformin or acarbose in this species have yet to be assessed. This study evaluated the pharmacokinetics of two dosage levels each of metformin or acarbose (given separately) in two small groups of young marmosets (n = 5/group) treated for 24 h to define the pharmacokinetics of each drug. The ability to rapidly and reliably dose socially housed marmosets with an oral form of acarbose or metformin that is well tolerated indicates that this species is a reliable model for testing acarbose and metformin in a safe and efficient way in a long-term intervention.

High intensity interval training improves physical performance in aged female mice: A comparison of mouse frailty assessment tools

Frailty syndrome increases the risk for disability and mortality, and is a major health concern amidst the geriatric shift in the population. High intensity interval training (HIIT), which couples bursts of vigorous activity interspersed with active recovery intervals, shows promise for the treatment of frailty. Here we compare and contrast five Fried physical phenotype and one deficit accumulation based mouse frailty assessment tools for identifying the impacts of HIIT on frailty and predicting functional capacity, underlying pathology, and survival in aged female mice. Our data reveal a 10-minute HIIT regimen administered 3-days-a-week for 8-weeks increased treadmill endurance, gait speed and maintained grip strength. One frailty tool identified a benefit of HIIT for frailty, but many were trending suggesting HIIT was beneficial for physical performance in these mice, but the 8-week timeframe may have been insufficient to induce frailty benefits. Finally, most frailty tools distinguished between surviving or non-surviving mice, whereas half correlated with functional capacity measured by nest building ability, and none correlated with underlying pathology. In summary, this study supports the ongoing development of mouse assessment tools as useful instruments for frailty research.

The Association Between Race and Frailty in Older Adults Presenting to a Nononcologic Urology Practice

OBJECTIVE

To explore whether there is an association between nonwhite race and frailty among older adults presenting to an academic nononcologic urology practice.

MATERIALS AND METHODS

This is a prospective study of individuals ages ≥65years presenting to a nononcologic urology practice between December 2015 and November 2016. All individuals had a Timed Up and Go Test (TUGT, where a slower TUGT time of ≥15 seconds is suggestive of frailty. TUGT times, race (white vs nonwhite), and other clinical data were extracted from the electronic medical record using direct queries. Multivariable logistic regression was used to identify the association between race and slower TUGT times while adjusting for age, gender, number of medications, body mass index, and number of urologic diagnoses.

RESULTS

Among the 1715 individuals in our cohort, 33.9% were of nonwhite race and 15.3% had TUGT ≥15 seconds. A higher percentage of nonwhite individuals had TUGT times ≥15 seconds compared to white individuals (23.6% vs 11.1%, P <.01). TUGT times ≥15 seconds were significantly associated with nonwhite race after adjusting for clinical factors (adjusted odds ratio 2.5, 95% confidence interval 1.8-3.3).

CONCLUSION

Among older adults presenting to an academic nononcologic urology practice, nonwhite race was associated with increased odds of frailty. A greater understanding of the relationship between race and frailty is needed to better address the needs of this vulnerable population.

Diabetes Management in Older Adults With Chronic Kidney Disease

PURPOSE OF REVIEW

Older adults often live with chronic disease including diabetes and its complications. In this review, we examine the complexity and heterogeneity of older adults with diabetes and chronic kidney disease, explore the nuances in their diabetes-related monitoring, and discuss their best diabetes management.

RECENT FINDINGS

Although there remains an overall lack of studies in older adults with diabetes and chronic kidney disease, recent reports have highlighted their vulnerabilities. These individuals face an increased risk of cognitive impairment and dementia, frailty, dysglycemia, polypharmacy, declining kidney function, and acute kidney injury. Their diabetes management should focus upon safer antihyperglycemic medications, close monitoring, and care individualization. Older adults with diabetes and chronic kidney disease are a complex population who requires careful diabetes management and monitoring. Research efforts might focus on improving the care and outcomes of these patients.

Frailty, nutrition-related parameters, and mortality across the adult age spectrum

BACKGROUND

Nutritional status and individual nutrients have been associated with frailty in older adults. The extent to which these associations hold in younger people, by type of malnutrition or grades of frailty, is unclear. Our objectives were to (1) evaluate the relationship between individual nutrition-related parameters and frailty, (2) investigate the association between individual nutrition-related parameters and mortality across frailty levels, and (3) examine whether combining nutrition-related parameters in an index predicts mortality risk across frailty levels.

METHODS

This observational study assembled 9030 participants aged ≥ 20 years from the 2003-2006 cohorts of the National Health and Nutrition Examination Survey who had complete frailty data. A 36-item frailty index (FI) was constructed excluding items related to nutritional status. We examined 62 nutrition-related parameters with established cut points: 34 nutrient intake items, 5 anthropometric measurements, and 23 relevant blood tests. The 41 nutrition-related parameters which were associated with frailty were combined into a nutrition index (NI). All-cause mortality data until 2011 were identified from death certificates.

RESULTS

All 5 anthropometric measurements, 21/23 blood tests, and 19/34 nutrient intake items were significantly related to frailty. Although most nutrition-related parameters were directly related to frailty, high alcohol consumption and high levels of serum alpha-carotene, beta-carotene, beta-cryptoxanthin, total cholesterol, and LDL-c were associated with lower frailty scores. Only low vitamin D was associated with increased mortality risk across all frailty levels. Seventeen nutrition-related parameters were associated with mortality in the 0.1-0.2 FI group, 11 in the 0.2-0.3 group, and 16 in the > 0.3 group. Overall, 393 (5.8%) of the participants had an NI score less than 0.1 (abnormality in ≤ 4 of the 41 parameters examined). Higher levels of NI were associated with higher mortality risk after adjusting for frailty and other covariates (HR per 0.1: 1.19 [95%CI 1.133-1.257]).

CONCLUSIONS

Most nutrition-related parameters were correlated to frailty, but only low vitamin D was associated with higher risk for mortality across levels of frailty. As has been observed with other age-related phenomena, even though many nutrition-related parameters were not significantly associated with mortality individually, when combined in an index, they strongly predicted mortality risk.

Long-term treatment with the mTOR inhibitor rapamycin has minor effect on clinical laboratory markers in middle-aged marmosets

Interventions to extend lifespan and improve health with increasing age would have significant impact on a growing aged population. There are now several pharmaceutical interventions that extend lifespan in laboratory rodent models with rapamycin, an inhibitor of mechanistic target of rapamycin (mTOR) being the most well studied. In this study, we report on the hematological effects in a cohort of middle-aged common marmosets (Callithrix jacchus) that were enrolled in a study to test the effects of daily rapamycin treatment on aging in this species. In addition, we assessed whether sex was a significant factor in either baseline assessment or as an interaction with rapamycin treatment. Among our cohort at baseline, we found few differences in either basic morphology or hematological markers of blood cell counts, metabolism or inflammation between male and female marmosets. After dosing with rapamycin, surprisingly we found trough blood concentrations of rapamycin were significantly lower in female compared to male marmosets. Despite this pharmacological difference, both sexes had only minor changes in cellular blood counts after 9 months of rapamycin. These data then suggest that the potential clinical hematological side effects of rapamycin are not likely outcomes of long-term rapamycin in relatively healthy, middle-aged marmosets.

Disability, quality of life and all-cause mortality in older Mexican adults: association with multimorbidity and frailty

BACKGROUND

Multimorbidity and frailty are relevant conditions among older adult population. There is growing evidence about their association with poor health outcomes like disability, worst quality of life, and death. Nonetheless, the independent associations of both conditions have been studied, and few evidence exists about an interaction between them. Our aims were to assess the association of frailty and multimorbidity with the disability, quality of life and all-cause mortality as well as to analyze a potential interaction between these conditions.

METHODS

Analytical samples included 1410 respondents for disability and quality of life, and 1792 for mortality. We performed a longitudinal analysis with older Mexican adults aged 50, using data collected from the WHO's Study on global AGEing and Adult Health Waves 1 and 2. Disability was measured using the World Health Organization Disability Assessment Schedule (WHODAS 2.0), and quality of life using the WHOQOL (WHO Quality of Life) instrument. All-cause mortality was determined by reviewing death certificates. Associations of frailty and multimorbidity with disability, quality of life and mortality were estimated using linear regression and Cox proportional hazards models.

RESULTS

Multimorbidity assessed through three patterns (cardiopulmonary, vascular-metabolic, and mental-musculoskeletal) was associated with the three outcomes in this study. Cardiopulmonary and mental-musculoskeletal patterns increased the WHODAS mean score (β = 5.05; p < 0.01 and β = 5.10; p < 0.01, respectively) and decreased WHOQOL score (β = - 1.81; p < 0.01 and β = - 2.99; p < 0.01, respectively). Vascular-metabolic was associated with mortality (HR = 1.47; p = 0.04), disability (β = 3.27; p < 0.01) and quality of life (β = - 1.30; p = 0.02). Frailty was associated with mortality (pre-frail: HR = 1.48; p = 0.02 and frail: HR = 1.68; p = 0.03), disability (pre-frail: β = 5.02; p < 0.01; frail: β = 13.29; p < 0.01) and quality of life (pre-frail: β = - 2.23; p < 0.01; frail: β = - 4.38; p < 0.01). Interaction terms of frailty and multimorbidity were not statistically significant.

CONCLUSIONS

Multimorbidity and frailty are important predictors of poor health outcomes. These results highlight the importance of carrying out health promotion and prevention actions as well as specific interventions aimed at older adults who suffer from multimorbidity and frailty, in such a way that deleterious effects on health can be avoided.

Short-term weight loss reverses obesity-induced microvascular endothelial dysfunction

Obesity is one of the major risk factors for cardiovascular diseases and its prevalence is increasing in all age groups, with the biggest impact observed in middle-aged and older adults. A critical mechanism by which obesity promotes vascular pathologies in these patients involves impairment of endothelial function. While endothelial dysfunction in large vessels promotes atherogenesis, obesity-induced microvascular endothelial dysfunction impairs organ perfusion and thereby is causally related to the pathogenesis of ischemic heart disease, chronic kidney disease, intermittent claudication, exercise intolerance, and exacerbates cognitive decline in aging. Reduction of weight via calorie-based diet and exercise in animal models of obesity results in significant improvement of endothelial function both in large vessels and in the microcirculation, primarily due to attenuation of oxidative stress and inflammation. Clinical data on the protective effects of weight loss on endothelial function is limited to studies of flow-mediated dilation assessed in brachial arteries. Currently, there is no guideline on testing the effects of different weight management strategies on microvascular endothelial function in obese patients. Here, we provide proof-of-concept that weight loss-induced improvement of microvascular endothelial function can be reliably assessed in the setting of a geriatric outpatient clinic using a fast, reproducible, non-invasive method: laser speckle contrast imaging-based measurement of endothelium-dependent microvascular responses during post-occlusive reactive hyperemia tests. Our study also provides initial evidence that short-term weight loss induced by consumption of a low-carbohydrate low-calorie diet can reverse microvascular endothelial dysfunction associated with obesity.

Association of metabolic syndrome and its components with all-cause and cardiovascular mortality in the elderly: A meta-analysis of prospective cohort studies

There is increasing evidence regarding the relationship between metabolic syndrome and mortality. However, previous research examining metabolic syndrome and mortality in older populations has produced mixed results. In addition, there is a clear need to identify and manage individual components of metabolic syndrome to decrease cardiovascular disease (CVD) mortality. In this meta-analysis, we searched the MEDLINE databases using PubMed, Cochrane Library, and EMBASE databases. Based on 20 prospective cohort studies, metabolic syndrome was associated with a higher risk of all-cause mortality [relative risk (RR), 1.23; 95% confidence interval (CI), 1.15-1.32; I = 55.9%] and CVD mortality (RR, 1.24; 95% CI, 1.11-1.39; I = 58.1%). The risk estimates of all-cause mortality for single components of metabolic syndrome were significant for higher values of waist circumference or body mass index (RR, 0.94; 95% CI, 0.88-1.00), higher values of blood glucose (RR, 1.19; 95% CI, 1.05-1.34), and lower values of high-density lipoprotein (HDL) cholesterol (RR, 1.11; 95% CI, 1.02-1.21). In the elderly population, metabolic syndrome was associated with an increased risk of all-cause and CVD mortality. Among the individual components of metabolic syndrome, increased blood glucose and HDL cholesterol levels were significantly associated with increased mortality. However, older obese or overweight individuals may have a decreased mortality risk. Thus, the findings of the current meta-analysis raise questions about the utility of the definition of metabolic syndrome in predicting all-cause mortality and CVD mortality in the elderly population.

The Older Adult with Diabetes and The Busy Clinicians

Busy primary care providers are in the frontline and see the bulk of older adults with diabetes. This vulnerable population is more prone to diabetic complications and hypoglycemia. In contrast to the younger patients with diabetes, lifestyle interventions are even more effective in older adults while the target A1c levels may need to be more relaxed for frail individuals. Geriatric syndromes can adversely affect diabetes care. A team with experts in different fields who understand the needs of older adults is essential for the adequate quality care of the whole individual with diabetes.

Hypertension impairs neurovascular coupling and promotes microvascular injury: role in exacerbation of Alzheimer's disease

Hypertension in the elderly substantially increases both the risk of vascular cognitive impairment (VCI) and Alzheimer's disease (AD); however, the underlying mechanisms are not completely understood. This review discusses the effects of hypertension on structural and functional integrity of cerebral microcirculation, including hypertension-induced alterations in neurovascular coupling responses, cellular and molecular mechanisms involved in microvascular damage (capillary rarefaction, blood-brain barrier disruption), and the genesis of cerebral microhemorrhages and their potential role in exacerbation of cognitive decline associated with AD. Understanding and targeting the hypertension-induced cerebromicrovascular alterations that are involved in the onset and progression of AD and contribute to cognitive impairment are expected to have a major role in preserving brain health in high-risk older individuals.

Demonstration of impaired neurovascular coupling responses in TG2576 mouse model of Alzheimer's disease using functional laser speckle contrast imaging

Increasing evidence from epidemiological, clinical, and experimental studies indicates that cerebromicrovascular dysfunction and microcirculatory damage play critical roles in the pathogenesis of many types of dementia in the elderly, including both vascular cognitive impairment (VCI) and Alzheimer's disease. Vascular contributions to cognitive impairment and dementia (VCID) include impairment of neurovascular coupling responses/functional hyperemia ("neurovascular uncoupling"). Due to the growing interest in understanding and pharmacologically targeting pathophysiological mechanisms of VCID, there is an increasing need for sensitive, easy-to-establish methods to assess neurovascular coupling responses. Laser speckle contrast imaging (LSCI) is a technique that allows rapid and minimally invasive visualization of changes in regional cerebromicrovascular blood perfusion. This type of imaging technique combines high resolution and speed to provide great spatiotemporal accuracy to measure moment-to-moment changes in cerebral blood flow induced by neuronal activation. Here, we provide detailed protocols for the successful measurement in neurovascular coupling responses in anesthetized mice equipped with a thinned-skull cranial window using LSCI. This method can be used to evaluate the effects of anti-aging or anti-AD treatments on cerebromicrovascular health.

Hypertension-induced synapse loss and impairment in synaptic plasticity in the mouse hippocampus mimics the aging phenotype: implications for the pathogenesis of vascular cognitive impairment

Strong epidemiological and experimental evidence indicates that hypertension has detrimental effects on the cerebral microcirculation and thereby promotes accelerated brain aging. Hypertension is an independent risk factor for both vascular cognitive impairment (VCI) and Alzheimer's disease (AD). However, the pathophysiological link between hypertension-induced cerebromicrovascular injury (e.g., blood-brain barrier disruption, increased microvascular oxidative stress, and inflammation) and cognitive decline remains elusive. The present study was designed to characterize neuronal functional and morphological alterations induced by chronic hypertension and compare them to those induced by aging. To achieve that goal, we induced hypertension in young C57BL/6 mice by chronic (4 weeks) infusion of angiotensin II. We found that long-term potentiation (LTP) of performant path synapses following high-frequency stimulation of afferent fibers was decreased in hippocampal slices obtained from hypertensive mice, mimicking the aging phenotype. Hypertension and advanced age were associated with comparable decline in synaptic density in the stratum radiatum of the mouse hippocampus. Hypertension, similar to aging, was associated with changes in mRNA expression of several genes involved in regulation of neuronal function, including down-regulation of Bdnf, Homer1, and Dlg4, which may have a role in impaired synaptic plasticity. Collectively, hypertension impairs synaptic plasticity, reduces synaptic density, and promotes dysregulation of genes involved in synaptic function in the mouse hippocampus mimicking the aging phenotype. These hypertension-induced neuronal alterations may impair establishment of memories in the hippocampus and contribute to the pathogenesis and clinical manifestation of both vascular cognitive impairment (VCI) and Alzheimer's disease (AD).