Operationalizing Frailty in the Atherosclerosis Risk in Communities Study Cohort

Mid-life plasma proteins associated with late-life prefrailty and frailty: a proteomic analysis

Physical frailty is a syndrome that typically manifests in later life, although the pathogenic process causing physical frailty likely begins decades earlier. To date, few studies have examined the biological signatures in mid-life associated with physical frailty later in life. Among 4,189 middle-aged participants (57.8 ± 5.0 years, 55.8% women) from the Atherosclerosis Risk in Community (ARIC) study, we evaluated the associations of 4,955 plasma proteins (log 2-transformed and standardized) measured using the SomaScan platform with their frailty status approximately 20 years later. Using multinomial logistic regression models adjusting for demographics, health behaviors, kidney function, total cholesterol, and comorbidities, 12 and 221 proteins were associated with prefrailty and frailty in later life, respectively (FDR p < 0.05). Top frailty-associated proteins included neurocan core protein (NCAN, OR = 0.66), fatty acid-binding protein heart (FABP3, OR = 1.62) and adipocyte (FABP4, OR = 1.65), as well proteins involved in the contactin-1 (CNTN1), toll-like receptor 5 (TLR5), and neurogenic locus notch homolog protein 1 (NOTCH1) signaling pathway relevant to skeletal muscle regeneration, myelination, and inflammation. Pathway analyses suggest midlife dysregulation of inflammation, metabolism, extracellular matrix, angiogenesis, and lysosomal autophagy among those at risk for late-life frailty. After further adjusting for midlife body mass index (BMI) - an established frailty risk factor - only CNTN1 (OR = 0.75) remained significantly associated with frailty. Post-hoc analyses demonstrated that the top 41 midlife frailty-associated proteins mediate 32% of the association between mid-life BMI and late-life frailty. Our findings provide new insights into frailty etiology earlier in the life course, enhancing the potential for prevention.

Associations of plasma proteomics and age-related outcomes with brain age in a diverse cohort

Machine learning models are increasingly being used to estimate "brain age" from neuroimaging data. The gap between chronological age and the estimated brain age gap (BAG) is potentially a measure of accelerated and resilient brain aging. Brain age calculated in this fashion has been shown to be associated with mortality, measures of physical function, health, and disease. Here, we estimate the BAG using a voxel-based elastic net regression approach, and then, we investigate its associations with mortality, cognitive status, and measures of health and disease in participants from Atherosclerosis Risk in Communities (ARIC) study who had a brain MRI at visit 5 of the study. Finally, we used the SOMAscan assay containing 4877 proteins to examine the proteomic associations with the MRI-defined BAG. Among N = 1849 participants (age, 76.4 (SD 5.6)), we found that increased values of BAG were strongly associated with increased mortality and increased severity of the cognitive status. Strong associations with mortality persisted when the analyses were performed in cognitively normal participants. In addition, it was strongly associated with BMI, diabetes, measures of physical function, hypertension, prevalent heart disease, and stroke. Finally, we found 33 proteins associated with BAG after a correction for multiple comparisons. The top proteins with positive associations to brain age were growth/differentiation factor 15 (GDF-15), Sushi, von Willebrand factor type A, EGF, and pentraxin domain-containing protein 1 (SEVP 1), matrilysin (MMP7), ADAMTS-like protein 2 (ADAMTS), and heat shock 70 kDa protein 1B (HSPA1B) while EGF-receptor (EGFR), mast/stem-cell-growth-factor-receptor (KIT), coagulation-factor-VII, and cGMP-dependent-protein-kinase-1 (PRKG1) were negatively associated to brain age. Several of these proteins were previously associated with dementia in ARIC. These results suggest that circulating proteins implicated in biological aging, cellular senescence, angiogenesis, and coagulation are associated with a neuroimaging measure of brain aging.

High Throughput Plasma Proteomics and Risk of Heart Failure and Frailty in Late Life

Importance

Heart failure (HF) and frailty frequently coexist and may share a common pathobiology, although the underlying mechanisms remain unclear. Understanding these mechanisms may provide guidance for preventing and treating both conditions.

Objective

To identify shared pathways between incident HF and frailty in late life using large-scale proteomics.

Design, Setting, and Participants

In this cohort study, 4877 aptamers (Somascan v4) were measured among participants in the community-based longitudinal Atherosclerosis Risk In Communities (ARIC) cohort study at visit 3 (V3; 1993-1995; n = 10 638) and at visit 5 (V5; 2011-2013; n = 3908). Analyses were externally replicated among 3189 participants in the Cardiovascular Health Study (CHS). Data analysis was conducted from February 2022 to June 2023.

Exposures

Protein aptamers, measured at study V3 and V5.

Main Outcomes and Measures

Outcomes assessed included incident HF hospitalization after V3 and after V5, prevalent frailty at V5, and incident frailty between V5 and visit 6 (V6; 2016-2017; n = 4131). Frailty was assessed using the Fried criteria. Analyses were adjusted for age, gender, race, field center, hypertension, diabetes, smoking status, body mass index, estimated glomerular filtration rate, prevalent coronary heart disease, prevalent atrial fibrillation, and history of myocardial infarction. Mendelian randomization (MR) analysis was performed to assess potential causal effects of candidate proteins on HF and frailty.

Results

A total of 4877 protein aptamers were measured among 10 638 participants at V3 (mean [SD] age, 60 [6] years; 4886 [46%] men). Overall, 286 proteins were associated with incident HF after V3 (822 events; P < 1.0 × 10-5), 83 of which were also associated with incident after V5 (336 events; P < 1.7 × 10-4). Among HF-free participants at V5 (n = 3908; mean [SD] age, 75 [5] years; 1861 [42%] men), 48 of 83 HF-associated proteins were associated with prevalent frailty (223 cases; P < 6.0 × 10-4), 18 of which were also associated with incident frailty at V6 (152 cases; P < 1.0 × 10-3). These proteins enriched fibrosis and inflammation pathways and demonstrated stronger associations with incident HF with preserved ejection fraction (HFpEF) than HF with reduced ejection fraction. All 18 proteins were associated with both prevalent frailty and incident HF in CHS. MR identified potential causal effects of several proteins on frailty and HF.

Conclusions and Relevance

In this study, the proteins associated with risk of HF and frailty enrich for pathways related to inflammation and fibrosis as well as risk of HFpEF. Several of these proteins could potentially contribute to the shared pathophysiology of frailty and HF.

Associations Between Prior Head Injury, Physical Functioning, and Frailty in the Atherosclerosis Risk in Communities Study

BACKGROUND

Older adults have the highest rates of head injury and are at the greatest risk for subsequent dysfunction, yet research on subsequent physical decline is limited. We sought to examine cross-sectional and prospective associations of head injury with physical functioning and frailty among older adults.

METHODS

A total of 5 598 Atherosclerosis Risk in Communities Study participants from Visit 5 (2011-13) underwent assessments of physical functioning (Short Physical Performance Battery [SPPB], comprised of gait speed, chair stands, and balance) and frailty (defined using established criteria) were followed through Visit 7 (2018-19). Head injury was self-reported or based on ICD-9 codes. Adjusted linear and multinomial logistic regression models were used to estimate associations. Prospective models incorporated inverse probability of attrition weights to account for death or attrition.

RESULTS

Participants were a mean age of 75 years, 58% were women, 22% were Black, and 27% had a prior head injury. Compared to individuals without head injury, individuals with head injury had worse physical functioning (SPPB total score, β-coefficient = -0.22, 95% CI: -0.35 to -0.09) and were more likely to be pre-frail (OR = 1.19, 95% CI: 1.04 to 1.35) or frail (OR = 1.40, 95% CI: 1.08 to 1.80) compared to robust. Prospectively, head injury was associated with a 0.02 m/s greater decline (95% CI: -0.04 to -0.01) in gait speed over a median of 5 years. Among baseline robust individuals (n = 1 847), head injury was associated with increased odds of becoming pre-frail (OR = 1.32, 95% CI: 1.04 to 1.67) or frail (OR = 1.92, 95% CI: 1.05 to 3.51) compared to robust.

CONCLUSIONS

Older adults with prior head injury had worse physical functioning and greater frailty at baseline and were more likely to become frail and walk slower over time, compared to individuals without head injury.

Moving towards the detection of frailty with biomarkers: A population health study

Aging adults experience increased health vulnerability and compromised abilities to cope with stressors, which are the clinical manifestations of frailty. Frailty is complex, and efforts to identify biomarkers to detect frailty and pre-frailty in the clinical setting are rarely reproduced across cohorts. We developed a predictive model incorporating biological and clinical frailty measures to identify robust biomarkers across data sets. Data were from two large cohorts of older adults: "Invecchiare in Chianti (Aging in Chianti, InCHIANTI Study") (n = 1453) from two small towns in Tuscany, Italy, and replicated in the Atherosclerosis Risk in Communities Study (ARIC) (n = 6508) from four U.S. communities. A complex systems approach to biomarker selection with a tree-boosting machine learning (ML) technique for supervised learning analysis was used to examine biomarker population differences across both datasets. Our approach compared predictors with robust, pre-frail, and frail participants and examined the ability to detect frailty status by race. Unique biomarker features identified in the InCHIANTI study allowed us to predict frailty with a model accuracy of 0.72 (95% confidence interval (CI) 0.66-0.80). Replication models in ARIC maintained a model accuracy of 0.64 (95% CI 0.66-0.72). Frail and pre-frail Black participant models maintained a lower model accuracy. The predictive panel of biomarkers identified in this study may improve the ability to detect frailty as a complex aging syndrome in the clinical setting. We propose several concrete next steps to keep research moving toward detecting frailty with biomarker-based detection methods.

Hearing Loss and Frailty among Older Adults: The Atherosclerosis Risk in Communities Study

OBJECTIVES

Hearing loss may contribute to frailty through cognitive and physical decline, but population-based evidence using validated measures remains scarce. We investigated the association of hearing loss with phenotypic frailty and its individual components and explored the potential protective role of hearing aid use.

DESIGN

Cross-sectional study of community-dwelling older adults at visit 6 (2016-2017) of the Atherosclerosis Risk in Communities (ARIC) study, a cohort study of older adults from 4 U.S. communities (Washington County, MD; Forsyth County, NC; Jackson, MS; and Minneapolis, MN).

SETTING AND PARTICIPANTS

Population-based study of 3179 participants (mean age = 79.2 years, 58.9% female).

METHODS

Pure-tone audiometry at 0.5-4 kHz was used to assess unaided hearing, and the better-hearing ear's pure-tone average was categorized as follows: no [≤25 dB hearing level (HL)], mild (26-40 dB HL), and moderate or greater (>40 dB HL) hearing loss. Hearing aid use was self-reported. The Fried/physical frailty phenotype was used to categorize frailty status (robust, pre-frail, or frail). Multivariable multinomial and logistic regression models were used to study the association of hearing loss/hearing aid use with frailty status and individual frailty components, respectively.

RESULTS

In our sample, 40% had mild and 27% had moderate or greater hearing loss (12% and 55% reported hearing aid use, respectively). Moderate or greater hearing loss was associated with greater odds of being pre-frail [odds ratio (OR), 1.25; 95% CI, 1.01-1.57] and frail (OR, 1.62; 95% CI, 1.06-2.47) vs robust, and greater odds of having slow gait, low physical activity, and exhaustion, compared with no hearing loss. Among those with hearing loss (>25 dB HL), compared with hearing aid users, nonusers had greater odds of being frail vs robust, and having unintentional weight loss, slow gait, and low physical activity.

CONCLUSIONS AND IMPLICATIONS

Hearing loss is associated with pre-frailty and frailty. Longitudinal studies are warranted to establish if hearing aid use may prevent or delay frailty onset.

Late-life plasma proteins associated with prevalent and incident frailty: A proteomic analysis

Proteomic approaches have unique advantages in the identification of biological pathways that influence physical frailty, a multifactorial geriatric syndrome predictive of adverse health outcomes in older adults. To date, proteomic studies of frailty are scarce, and few evaluated prefrailty as a separate state or examined predictors of incident frailty. Using plasma proteins measured by 4955 SOMAmers in the Atherosclerosis Risk in Community study, we identified 134 and 179 proteins cross-sectionally associated with prefrailty and frailty, respectively, after Bonferroni correction (p < 1 × 10-5 ) among 3838 older adults aged ≥65 years, adjusting for demographic and physiologic factors and chronic diseases. Among them, 23 (17%) and 82 (46%) were replicated in the Cardiovascular Health Study using the same models (FDR p < 0.05). Notably, higher odds of prefrailty and frailty were observed with higher levels of growth differentiation factor 15 (GDF15; pprefrailty  = 1 × 10-15 , pfrailty  = 2 × 10-19 ), transgelin (TAGLN; pprefrailty  = 2 × 10-12 , pfrailty  = 6 × 10-22 ), and insulin-like growth factor-binding protein 2 (IGFBP2; pprefrailty  = 5 × 10-15 , pfrailty  = 1 × 10-15 ) and with a lower level of growth hormone receptor (GHR, pprefrailty  = 3 × 10-16 , pfrailty  = 2 × 10-18 ). Longitudinally, we identified 4 proteins associated with incident frailty (p < 1 × 10-5 ). Higher levels of triggering receptor expressed on myeloid cells 1 (TREM1), TAGLN, and heart and adipocyte fatty-acid binding proteins predicted incident frailty. Differentially regulated proteins were enriched in pathways and upstream regulators related to lipid metabolism, angiogenesis, inflammation, and cell senescence. Our findings provide a set of plasma proteins and biological mechanisms that were dysregulated in both the prodromal and the clinical stage of frailty, offering new insights into frailty etiology and targets for intervention.

Bidirectional Association Between Frailty and Cardiac Structure and Function: The Atherosclerosis Risk in Communities Study

Background Frailty and heart failure frequently coexist in late life. Limited data exist regarding the longitudinal associations of frailty and subclinical cardiac dysfunction. We aim to quantify the association of frailty with longitudinal changes in cardiac function and of cardiac function with progression in frailty status in older adults. Methods and Results Participants in the Atherosclerosis Risk in Communities cohort underwent frailty assessments at Visit 5 (V5; 2011-2013), V6 (2016-2017), and V7 (2018-2019), and echocardiographic assessments at V5 and V7. We assessed the association between frailty status at V5 and changes in frailty status from V5 to V7 and changes in cardiac function over 6 years. We then evaluated the association of cardiac function measured at Visit 5 with progression in frailty status over 4 years. Multivariable regression models adjusted for demographics and comorbidities. Among 2574 participants free of heart failure at V5 and V7 (age 74±4 years at V5 and 81±4 years at V7), 3% (n=83) were frail. Frailty at V5 was associated with greater left atrial volume index and E/e' ratio at V5 and 7. Participants who transitioned from robust at V5 to frail at V7 demonstrated greater increases in left ventricular mass index, left atrial volume index, and E/e' over the same period. Among 1648 robust participants at Visit 5, greater left ventricular mass index and mean wall thickness, lower tissue Doppler imaging e', and higher E/e' ratio at Visit 5 were associated with progression in frailty status. Conclusions Among robust, older adults free of heart failure, progression in frailty and subclinical left ventricular remodeling and diastolic dysfunction are interrelated.

Stages of Valvular Heart Disease Among Older Adults in the Community: The Atherosclerosis Risk in Communities Study

BACKGROUND

Limited data exist on American College of Cardiology/American Heart Association valvular heart disease (VHD) stage prevalence, progression, and association with incident cardiovascular diseases in late life.

METHODS

Participants in the ARIC study (Atherosclerosis Risk in Communities), a prospective community-based cohort study, underwent protocol echocardiography at ARIC visits 5 (2011-2013) and 7 (2018-2019), and their aortic stenosis, aortic regurgitation, mitral stenosis, and mitral regurgitation stage were defined according to American College of Cardiology/American Heart Association guidelines. The overall VHD stage prevalence at visit 5 was measured. The associations between VHD stages and incident adjudicated death, heart failure, coronary heart disease, stroke, and atrial fibrillation were assessed with Cox proportional hazard models adjusted for age, sex, race, hypertension, diabetes, prior myocardial infarction, heart failure, body mass index, study center, systolic blood pressure, estimated glomerular filtration rate, and low-density lipoprotein at visit 5. Longitudinal changes in VHD stage prevalence over ≈6 years were estimated with inverse probability of attrition weights to account for participant attrition.

RESULTS

Among 6118 ARIC participants, the mean±SD age was 76±5 years, 42% were male, and 22% reported Black race. Stage A VHD was present in 39%, stage B in 17%, and stage C/D in 1.1%;, 0.7% had previously undergone valve replacement or repair. A graded association was observed between stage A, B, and C/D VHD and risk of all-cause mortality, incident heart failure, incident atrial fibrillation, and incident coronary heart disease, but not incident stroke. Similar findings were observed for stages of each valvular lesion individually. During the 6.6 years (interquartile range, 6.1-7.0 years) between visits 5 and 7 (mean age, 81±4 years), the prevalence of freedom from VHD stage decreased from 43% to 24%, whereas the prevalence of stage C/D VHD increased from 1% to 7%.

CONCLUSIONS

Subclinical VHD is common in older adults, with 39% at risk (stage A) and 17% with progressive VHD (stage B), and is independently associated with risk of incident cardiovascular events. VHD stages progress over 6 years in late life, with a several-fold increase in prevalence of severe VHD (stage C/D), highlighting the public health importance of interventions to mitigate VHD progression.

Risk factors for frailty in elderly Japanese people who received Ningen Dock: a cross-sectional study

Background

Frailty is a clinical condition characterized by increased vulnerability to adverse health outcomes. Elderly people are screened for frailty as part of preventative care. However, the risk factors for frailty among older adults who undergo Ningen Dock, a comprehensive medical checkup, remain unclear. Thus, this cross-sectional study aims to identify the risk factors for frailty in older adults who received Ningen Dock. The study included 372 participants over 65 years of age who underwent Ningen Dock at the Health Care Center of Gunma Chuo Hospital between April 2019 and March 2020. Frailty was defined using the Kihon Checklist, a basic checklist. Clinical variables were obtained from Ningen Dock records, a vascular function test, and a questionnaire on medication, among others. Multivariate ordinal logistic regression models were used to assess risk factors.

Results

Prevalence for frailty and pre-frailty was 12.6% and 26.6%, respectively. The mean age of participants was 72.0 ± 5.1 years old, and 43.5% were female. Compared with systolic blood pressure (SBP) ≥ 130 mmHg, the odds ratios for the 100–129 mmHg and < 100 mmHg groups were 2.43 (P = 0.020) and 8.95 (P <0.001). The odds ratio for the ≥ 7 medications group medications was 3.64 (P = 0.003) compared to 0–2 medications. Compared with serum iron ≥ 126 μg/dL, the odds ratio for ≤ 85 μg/dL was 2.91 (P = 0.002). The odds ratio for total bilirubin ≤ 0.6 mg/dL was 2.49 (P = 0.011) compared with > 0.6 mg/dL. Compared with an exercise habit of ≥ 4 metabolic equivalents (METs), the odds ratio for < 2 METs/week was 2.45 (P < 0.001). The odds ratio for the cardio-ankle vascular index (CAVI) ≥ 9 group was 1.84 (P = 0.020) compared to < 9.

Conclusions

In older adults who received Ningen Dock, SBP < 100 mmHg, medications ≥ 7, serum iron ≤ 85 μg/dL, total bilirubin ≤ 0.6 mg/dL, exercise habits < 2 METs, and CAVI ≥ 9 were associated with frailty.

American Diabetes Association Framework for Glycemic Control in Older Adults: Implications for Risk of Hospitalization and Mortality

OBJECTIVE

The 2021 American Diabetes Association (ADA) guidelines recommend different A1C targets in older adults that are based on comorbid health status. We assessed risk of mortality and hospitalizations in older adults with diabetes across glycemic control (A1C <7%, 7 to <8%, ≥8%) and ADA-defined health status (healthy, complex/intermediate, very complex/poor) categories.

RESEARCH DESIGN AND METHODS

Prospective cohort analysis of older adults aged 66-90 years with diagnosed diabetes in the Atherosclerosis Risk in Communities (ARIC) study.

RESULTS

Of the 1,841 participants (56% women, 29% Black), 32% were classified as healthy, 42% as complex/intermediate, and 27% as very complex/poor health. Over a median 6-year follow-up, there were 409 (22%) deaths and 4,130 hospitalizations (median [25th-75th percentile] 1 per person [0-3]). In the very complex/poor category, individuals with A1C ≥8% (vs. <7%) had higher mortality risk (hazard ratio 1.76 [95% CI 1.15-2.71]), even after adjustment for glucose-lowering medication use. Within the very complex/poor health category, individuals with A1C ≥8% (vs. <7%) had more hospitalizations (incidence rate ratio [IRR] 1.41 [95% CI 1.03-1.94]). In the complex/intermediate group, individuals with A1C ≥8% (vs. <7%) had more hospitalizations, even with adjustment for glucose-lowering medication use (IRR 1.64 [1.21-2.24]). Results were similar, but imprecise, when the analysis was restricted to insulin or sulfonylurea users (n = 663).

CONCLUSIONS

There were substantial differences in mortality and hospitalizations across ADA health status categories, but older adults with A1C <7% were not at elevated risk, regardless of health status. Our results support the 2021 ADA guidelines and indicate that <7% is a reasonable treatment goal in some older adults with diabetes.

Changes in Hypertension Control in a Community-Based Population of Older Adults, 2011-2013 to 2016-2017

BACKGROUND

2014 hypertension guidelines raised treatment goals in older adults. The objective was to examine changes in blood pressure (BP) control (<140/90 mm Hg) from 2011-2013 to 2016-2017 among Black and white older adults with treated hypertension.

METHODS

Participants were 1,600 white and 650 Black adults aged 71-90 years in the Atherosclerosis Risk in Communities (ARIC) Study with treated hypertension in 2011-2013 (baseline) who had BP measured in 2016-2017 (follow-up). Predictors of changes in BP control were examined by race.

RESULTS

BP was controlled among 75.3% of white and 65.7% of Black participants at baseline and 59.0% of white and 56.5% of Black participants at follow-up. Among those with baseline BP control, risk factors for incident uncontrolled BP included age (relative risk [RR] 1.15 per 5 years, 95% confidence interval [CI] 1.07-1.25), female sex (RR 1.36, 95% CI 1.16-1.60), and chronic kidney disease (RR 1.19, 95% CI 1.01-1.40) among white participants, and hypertension duration (RR 1.14 per 5 years, 95% CI 1.03-1.27) and diabetes (RR 1.48, 95% CI 1.15-1.91) among Black participants. Among those with uncontrolled BP at baseline, white females vs. males (RR 0.60, 95% CI 0.46-0.78) and Black participants with chronic kidney disease vs. without (RR 0.58, 95% CI 0.36-0.93) were less likely to have incident controlled BP.

CONCLUSIONS

BP control decreased among white and Black older adults. Black individuals with diabetes or chronic kidney disease were less likely to have controlled BP at follow-up. Higher treatment goals may have contributed to these findings and unintended differences by race.

Glycaemic markers and all-cause mortality in older adults with and without diabetes: the Atherosclerosis Risk in Communities (ARIC) study

AIMS/HYPOTHESIS

There is controversy regarding the performance of HbA1c in old age. We evaluated the prognostic value of HbA1c and other glycaemic markers (fructosamine, glycated albumin, fasting glucose) with mortality risk in older adults (66-90 years).

METHODS

This was a prospective analysis of 5636 participants (31% with diagnosed diabetes, mean age 76, 58% female, 21% black) in the Atherosclerosis Risk in Communities (ARIC) study, baseline 2011-2013. We used Cox regression to examine associations of glycaemic markers (modelled in categories) with mortality risk, stratified by diagnosed diabetes status.

RESULTS

During a median of 6 years of follow-up, 983 deaths occurred. Among older adults with diabetes, 30% had low HbA1c (<42 mmol/mol [<6.0%]) and 10% had high HbA1c (≥64 mmol/mol [≥8.0%]); low (HR 1.32 [95% CI 1.04, 1.68]) and high (HR 1.86 [95% CI 1.32, 2.62]) HbA1c were associated with mortality risk vs HbA1c 42-52 mmol/mol (6.0-6.9%) after demographic adjustment. Low fructosamine and glycated albumin were not associated with mortality risk. Both low and high fasting glucose were associated with mortality risk. After further adjustment for lifestyle and clinical risk factors, high HbA1c (HR 1.81 [95% CI 1.28, 2.56]), fructosamine (HR 1.96 [95% CI 1.43-2.69]), glycated albumin (HR 1.81 [95% CI 1.33-2.47]) and fasting glucose (HR 1.81 [95% CI 1.24, 2.66]) were associated with mortality risk. Low HbA1c and fasting glucose were no longer significantly associated with mortality risk. Among participants without diabetes, associations of glycaemic markers with mortality risk were less robust.

CONCLUSIONS/INTERPRETATION

Elevated HbA1c, fructosamine, glycated albumin and fasting glucose were associated with risk of mortality in older adults with diabetes. Low HbA1c and fasting glucose may be markers of poor prognosis but are possibly confounded by health status. Our findings support the clinical use of HbA1c in older adults with diabetes. Graphical abstract.

Sphingolipids and physical function in the Atherosclerosis Risk in Communities (ARIC) study

Long-chain sphingomyelins (SMs) may play an important role in the stability of myelin sheath underlying physical function. The objective of this study was to examine the cross-sectional and longitudinal associations of long-chain SMs [SM (41:1), SM (41:2), SM (43:1)] and ceramides [Cer (41:1) and Cer (43:1)] with physical function in the Atherosclerosis Risk in Communities (ARIC) study. Plasma concentrations of SM (41:1), SM (41:2), SM (43:1), Cer (41:1) and Cer (43:1) were measured in 389 ARIC participants in 2011-13. Physical function was assessed by grip strength, Short Physical Performance Battery (SPPB), 4-m walking speed at both 2011-13 and 2016-17, and the modified Rosow-Breslau questionnaire in 2016-2017. Multivariable linear and logistic regression analyses were performed, controlling for demographic and clinical confounders. In cross-sectional analyses, plasma concentrations of SM 41:1 were positively associated with SPPB score (β-coefficients [95% confidence internal]: 0.33 [0.02, 0.63] per 1 standard deviation [SD] increase in log-transformed concentration, p value 0.04), 4-m walking speed (0.042 m/s [0.01, 0.07], p value 0.003), and negatively with self-reported disability (odds ratio = 0.73 [0.65, 0.82], p value < 0.0001). Plasma concentrations of the five metabolites examined were not significantly associated with longitudinal changes in physical function or incidence of poor mobility. In older adults, plasma concentrations of long-chain SM 41:1 were cross-sectionally positively associated with physical function.

Long-Term Association of Venous Thromboembolism With Frailty, Physical Functioning, and Quality of Life: The Atherosclerosis Risk in Communities Study

Background

Relatively little is known about the long‐term consequences of venous thromboembolism (VTE) on physical functioning. We compared long‐term frailty status, physical function, and quality of life among survivors of VTE with survivors of coronary heart disease (CHD) and stroke, and with those without these diseases.

Methods and Results

Cases of VTE, CHD, and stroke were continuously identified since ARIC (Atherosclerosis Risk in Communities Study) recruitment during 1987 to 1989. Functional measures were objectively captured at ARIC clinic visits 5 (2011–2013) and 6 (2016–2017); quality of life was self‐reported. The 6161 participants at visit 5 were, on average, 75.7 (range, 66–90) years of age. By visit 5, 3.2% had had a VTE, 6.9% CHD, and 3.4% stroke. Compared with those without any of these conditions, VTE survivors were more likely to be frail (odds ratio [OR], 3.11; 95% CI, 1.80–5.36) and have low (<10) versus good scores on the Short Physical Performance Battery (OR, 3.59; 95% CI, 2.36–5.47). They also had slower gait speed, less endurance, and lower physical quality of life. VTE survivors were similar to coronary heart disease and stroke survivors on categorical frailty and outcomes on Short Physical Performance Battery assessment. When score on the Short Physical Performance Battery instrument was modeled continuously, VTE survivors performed better than stroke survivors but worse than CHD survivors.

Conclusions

VTE survivors had triple the odds of frailty and poorer physical function than those without the vascular diseases considered. Their function was somewhat worse than that of CHD survivors, but better than stroke survivors. These findings suggest that VTE patients may benefit from additional efforts to improve postevent physical functioning.

Performance of High-Sensitivity Cardiac Troponin Assays to Reflect Comorbidity Burden and Improve Mortality Risk Stratification in Older Adults With Diabetes

OBJECTIVE

Incorporation of comorbidity burden to inform diabetes management in older adults remains challenging. High-sensitivity cardiac troponins are objective, quantifiable biomarkers that may improve risk monitoring in older adults. We assessed the associations of elevations in high-sensitivity cardiac troponin I (hs-cTnI) and T (hs-cTnT) with comorbidities and improvements in mortality risk stratification.

RESEARCH DESIGN AND METHODS

We used logistic regression to examine associations of comorbidities with elevations in either troponin (≥85th percentile) among 1,835 participants in the Atherosclerosis Risk in Communities (ARIC) Study with diabetes (ages 67-89 years, 43% male, 31% black) at visit 5 (2011-2013). We used Cox models to compare associations of high cardiac troponins with mortality across comorbidity levels.

RESULTS

Elevations in either troponin (≥9.4 ng/L for hs-cTnI, ≥25 ng/L for hs-cTnT) were associated with prevalent coronary heart disease, heart failure, chronic kidney disease, pulmonary disease, hypoglycemia, hypertension, dementia, and frailty. Over a median follow-up of 6.2 years (418 deaths), both high hs-cTnI and high hs-cTnT further stratified mortality risk beyond comorbidity levels; those with a high hs-cTnI or hs-cTnT and high comorbidity were at highest mortality risk. Even among those with low comorbidity, a high hs-cTnI (hazard ratio 3.0 [95% CI 1.7, 5.4]) or hs-cTnT (hazard ratio 3.3 [95% CI 1.8, 6.2]) was associated with elevated mortality.

CONCLUSIONS

Many comorbidities were reflected by both hs-cTnI and hs-cTnT; elevations in either of the troponins were associated with higher mortality risk beyond comorbidity burden. High-sensitivity cardiac troponins may identify older adults at high mortality risk and be useful in guiding clinical care of older adults with diabetes.

Midlife Systemic Inflammation Is Associated With Frailty in Later Life: The ARIC Study

BACKGROUND

Evidence suggests that systemic inflammation may have a mechanistic role in age-related frailty, yet prospective data is limited. We examined whether systemic inflammation during midlife was associated with late-life frailty within the community-based Atherosclerosis Risk in Communities Study.

METHODS

Plasma levels of four inflammatory markers (fibrinogen, von Willebrand factor, and Factor VIII, and white blood cell count) were measured during Visit 1 (1987-1989; mean age: 52 [5]), standardized into z-scores, and combined to create an inflammation composite score. High-sensitivity C-reactive protein (CRP) was measured 3 (Visit 2, 1990-1992) and 9 (Visit 4, 1996-1999) years later. Frailty was evaluated in 5,760 participants during late life (Visit 5, 2011-2013; mean age: 75 [5]). Analyses were adjusted for demographic and physiological variables, and midlife medical comorbidity using logistic regression.

RESULTS

A 1 SD increase in midlife inflammation composite score was associated with higher odds of frailty 24 years later (odds ratio [OR] = 1.39, 95% confidence interval [CI]: 1.18-1.65). Similarly, each standard deviation increase in Visit 2 CRP (OR = 1.24, 95% CI: 1.09-1.40) and Visit 4 CRP (OR = 1.35, 95% CI: 1.19-1.53) was associated with a higher odds of frailty 21 and 15 years later. Participants who maintained elevated CRP (≥3 mg/L) at Visits 2 and 4 or transitioned to a state of elevated CRP during this period were more likely to subsequently meet frailty criteria compared to those who maintained low CRP. These associations were stronger among white, compared to African American, participants (p-interactions < .038).

CONCLUSIONS

Systemic inflammation during midlife may independently promote pathophysiological changes underlying frailty in a subset of the population.

Independent Association of Plasma Hydroxysphingomyelins With Physical Function in the Atherosclerosis Risk in Communities (ARIC) Study

Background

Plasma metabolites such as phosphatidylcholines and sphingomyelins (SMs) are associated with an age-related cognitive decline. However, their relations to age-related physical function decline remain largely unknown.

Methods

We examined the cross-sectional relations of 12 plasma metabolites (including four phosphatidylcholines and four SMs) with physical function in 383 older adults in the At herosclerosis Risk in Communities Study at the fifth exam (2011-2013, mean age [standard deviation (SD)]: 78.0 [5.5], 54.4% women, 28.3% African Americans). Physical function was assessed using grip strength, Short Physical Performance Battery, and 4-m walking speed. Individual metabolites were log-transformed and standardized. Multivariable linear regression was performed to account for demographics, APOE genotype, cardiovascular risk factors, comorbidities, use of antihypertensive and lipid-lowering medications, depressive symptoms, and cognition.

Results

Lower concentrations of asymmetric dimethylarginine and higher concentrations of SM (OH) C22:1, SM (OH) C22:2, and SM (OH) C24:1 were associated with physical function measures. In particular, SM (OH) C22:1 and SM (OH) C24:1 were associated with all three measures of physical function: β-coefficients (95% confidence interval) with grip strength were 0.89 kg (0.00, 1.78) and 0.86 kg (0.10, 1.61) per 1 SD higher concentration, respectively; with Short Physical Performance Battery score, were 0.61 (0.34, 0.88) and 0.41 (0.19, 0.63) per 1 SD difference, respectively; with 4-m walking speed were 0.035 m/s (0.013, 0.056) and 0.035 m/s (0.028, 0.047), respectively.

Conclusions

Plasma SM (OH)s may be independently associated with physical function in older adults.

Controlling for Frailty in Pharmacoepidemiologic Studies of Older Adults: Validation of an Existing Medicare Claims-based Algorithm

BACKGROUND

Frailty is a geriatric syndrome characterized by weakness and weight loss and is associated with adverse health outcomes. It is often an unmeasured confounder in pharmacoepidemiologic and comparative effectiveness studies using administrative claims data.

METHODS

Among the Atherosclerosis Risk in Communities (ARIC) Study Visit 5 participants (2011-2013; n = 3,146), we conducted a validation study to compare a Medicare claims-based algorithm of dependency in activities of daily living (or dependency) developed as a proxy for frailty with a reference standard measure of phenotypic frailty. We applied the algorithm to the ARIC participants' claims data to generate a predicted probability of dependency. Using the claims-based algorithm, we estimated the C-statistic for predicting phenotypic frailty. We further categorized participants by their predicted probability of dependency (<5%, 5% to <20%, and ≥20%) and estimated associations with difficulties in physical abilities, falls, and mortality.

RESULTS

The claims-based algorithm showed good discrimination of phenotypic frailty (C-statistic = 0.71; 95% confidence interval [CI] = 0.67, 0.74). Participants classified with a high predicted probability of dependency (≥20%) had higher prevalence of falls and difficulty in physical ability, and a greater risk of 1-year all-cause mortality (hazard ratio = 5.7 [95% CI = 2.5, 13]) than participants classified with a low predicted probability (<5%). Sensitivity and specificity varied across predicted probability of dependency thresholds.

CONCLUSIONS

The Medicare claims-based algorithm showed good discrimination of phenotypic frailty and high predictive ability with adverse health outcomes. This algorithm can be used in future Medicare claims analyses to reduce confounding by frailty and improve study validity.

Heart Failure and Frailty in the Community-Living Elderly Population: What the UFO Study Will Tell Us

Heart failure and frailty are clinical syndromes that present with overlapping phenotypic characteristics. Importantly, their co-presence is associated with increased mortality and morbidity. While mechanical and electrical device therapies for heart failure are vital for select patients with advanced stage disease, the majority of patients and especially those with undiagnosed heart failure would benefit from early disease detection and prompt initiation of guideline-directed medical therapies. In this article, we review the problematic interactions between heart failure and frailty, introduce a focused cardiac screening program for community-living elderly initiated by a mobile communication device app leading to the Undiagnosed heart Failure in frail Older individuals (UFO) study, and discuss how the knowledge of pre-frailty and frailty status could be exploited for the detection of previously undiagnosed heart failure or advanced cardiac disease. The widespread use of mobile devices coupled with increasing availability of novel, effective medical and minimally invasive therapies have incentivized new approaches to heart failure case finding and disease management.

Frailty and Comorbidities Among Survivors of Adolescent and Young Adult Cancer: A Cross-Sectional Examination of a Hospital-Based Survivorship Cohort

PURPOSE

Cancer survivors are at increased risk for the early development of age-related chronic medical conditions compared with peers without a history of cancer; however, little is known regarding the burden of these conditions among survivors of adolescent and young adult (AYA) cancers. In response, we sought to determine the prevalence of specific comorbidities and frailty among AYAs (15-39 years old at diagnosis) enrolled in a cancer survivorship cohort.

METHODS

Using a cross-sectional survey of a tertiary medical center-based cancer survivorship cohort, we determined the prevalence of specific comorbidities and frailty using the survey-based FRAIL assessment. In separate models adjusting for age, we estimated prevalence ratios (PRs) for the associations between patient characteristics and (1) any comorbidity and (2) frailty or prefrailty using log-binomial models.

RESULTS

We identified 271 AYA cancer survivors, most of whom were 30-39 years old at survey (57%). A majority of survivors (n = 163, 60%) reported having at least one comorbidity with the most common being depression (28%), anxiety (27%), asthma (17%), high cholesterol (15%), and hypertension (15%). Of the 184 AYA survivors at least 1 year from cancer diagnosis, 19 (10%) were classified as frail and 39 (21%) as prefrail. Survivors who were smokers (PR 2.0, 95% confidence interval [CI]: 1.16-3.56); obese (PR 1.7, 95% CI: 1.10-2.55); uninsured (PR 2.7, 95% CI: 1.63-4.59); or who reported comorbid depression or anxiety (PR 2.4, 95% CI: 1.51-3.67) were more likely to be frail or prefrail.

CONCLUSIONS

The prevalence of frailty and comorbidities is high among AYA cancer survivors suggestive of accelerated aging.

Cardiovascular Dysfunction and Frailty Among Older Adults in the Community: The ARIC Study

Background

The contribution of cardiovascular dysfunction to frailty in older adults is uncertain. This study aimed to define the relationship between frailty and cardiovascular structure and function, and determine whether these associations are independent of coexisting abnormalities in other organ systems.

Methods

We studied 3,991 older adults (mean age 75.6±5.0 years; 59% female) from the Atherosclerosis Risk in Communities (ARIC) Study in whom the following six organ systems were uniformly assessed: cardiac (by echocardiography), vascular (by ankle-brachial-index and pulse-wave-velocity), pulmonary (by spirometry), renal (by estimated glomerular filtration rate), hematologic (by hemoglobin), and adipose (by body mass index and bioimpedance). Frailty was defined by the presence of ≥3 of the following: low strength, low energy, slowed motor performance, low physical activity, or unintentional weight loss.

Results

Two hundred eleven (5.3%) participants were frail. In multivariable analyses adjusted for demographics, diabetes, hypertension, and measures of other organ system function, frailty was independently and additively associated with left ventricular hypertrophy (odds ratio [OR] = 1.72; 95% confidence interval [CI] = 1.30-2.40), reduced global longitudinal strain (reflecting systolic function; OR = 1.68; 95% CI = 1.16-2.44), and greater left atrial volume index (reflecting diastolic function; OR = 1.60; 95% CI = 1.13-2.27), which together demonstrated the greatest association with frailty (OR = 2.10; 95% CI = 1.57-2.82) of the systems studied. Lower magnitude associations were observed for vascular and pulmonary abnormalities, anemia, and impaired renal function. Cardiovascular abnormalities remained associated with frailty after excluding participants with prevalent cardiovascular disease.

Conclusions

Abnormalities of cardiac structure and function are independently associated with frailty, and together show the greatest association with frailty among the organ systems studied.

Frailty, Kidney Function, and Polypharmacy: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Frail individuals are at increased risk for poor outcomes, including adverse drug events. Kidney function is often compromised in frailty and is a key consideration in medication choice and dosing; however, creatinine-based measures of kidney function may be biased in frail individuals.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

4,987 community-dwelling older men and women with complete data who participated in visit 5 of the Atherosclerosis Risk in Communities (ARIC) Study (2011-2013).

PREDICTORS

Kidney measures included glomerular filtration rate (GFR) estimated using serum creatinine (eGFRcr) and serum cystatin C level (eGFRcys) and urine albumin-creatinine ratio.

OUTCOME

Frailty, defined using established criteria of 3 or more frailty characteristics (weight loss, slowness, exhaustion, weakness, and low physical activity).

RESULTS

341 (7%) participants were classified as frail, 1,475 (30%) had eGFRcr<60mL/min/1.73m2, 2,480 (50%) had eGFRcys<60mL/min/1.73m2, and 1,006 (20%) had albuminuria with albumin excretion ≥ 30mg/g. Among frail participants, prevalences of eGFRcr and eGFRcys<60mL/min/1.73m2 were 45% and 77%, respectively. Adjusted for covariates, frailty showed a moderate association with eGFRcr and a strong association with eGFRcys and albumin-creatinine ratio. Frail individuals with eGFRcr of 60 to <75mL/min/1.73m2 were frequently reclassified to lower eGFR categories using eGFRcys (49% to 45-<60, 32% to 30-<45, and 3% to <30mL/min/1.73m2). Hyperpolypharmacy (taking ≥10 classes of medications) was more common in frail individuals (54% vs 38% of nonfrail), including classes requiring kidney clearance (eg, digoxin) and associated with falls and subsequent complications (eg, hypnotic/sedatives and anticoagulants).

LIMITATIONS

Cross-sectional study design.

CONCLUSIONS

Frail individuals had a high prevalence of reduced kidney function, with large discrepancies when reduced kidney function was classified by eGFRcys versus eGFRcr. Given the substantial medication burden and uncertainty in chronic kidney disease classification, confirmation of kidney function with alternative biomarkers may be warranted to ensure careful prescribing practices in this vulnerable population.