Effect of Aspirin on Activities of Daily Living Disability in Community-Dwelling Older Adults

Aging and Inflammation

Aging can be conceptualized as the progressive disequilibrium between stochastic damage accumulation and resilience mechanisms that continuously repair that damage, which eventually cause the development of chronic disease, frailty, and death. The immune system is at the forefront of these resilience mechanisms. Indeed, aging is associated with persistent activation of the immune system, witnessed by a high circulating level of inflammatory markers and activation of immune cells in the circulation and in tissue, a condition called "inflammaging." Like aging, inflammaging is associated with increased risk of many age-related pathologies and disabilities, as well as frailty and death. Herein we discuss recent advances in the understanding of the mechanisms leading to inflammaging and the intrinsic dysregulation of the immune function that occurs with aging. We focus on the underlying mechanisms of chronic inflammation, in particular the role of NF-κB and recent studies targeting proinflammatory mediators. We further explore the dysregulation of the immune response with age and immunosenescence as an important mechanistic immune response to acute stressors. We examine the role of the gastrointestinal microbiome, age-related dysbiosis, and the integrated stress response in modulating the inflammatory "response" to damage accumulation and stress. We conclude by focusing on the seminal question of whether reducing inflammation is useful and the results of related clinical trials. In summary, we propose that inflammation may be viewed both as a clinical biomarker of the failure of resilience mechanisms and as a causal factor in the rising burden of disease and disabilities with aging. The fact that inflammation can be reduced through nonpharmacological interventions such as diet and exercise suggests that a life course approach based on education may be a successful strategy to increase the health span with few adverse consequences.

Epigenetic age acceleration and the risk of frailty, and persistent activities of daily living (ADL) disability

BACKGROUND

Epigenetic ageing is among the most promising ageing biomarkers and may be a useful marker of physical function decline, beyond chronological age. This study investigated whether epigenetic age acceleration (AA) is associated with the change in frailty scores over 7 years and the 7-year risk of incident frailty and persistent Activities of Daily Living (ADL) disability among 560 Australians (50.7% females) aged ≥70 years.

METHODS

Seven AA indices, including GrimAge, GrimAge2, FitAge and DunedinPACE, were estimated from baseline peripheral-blood DNA-methylation. Frailty was assessed using both the 67-item deficit-accumulation frailty index (FI) and Fried phenotype (Fried). Persistent ADL disability was defined as loss of ability to perform one or more basic ADLs for at least 6 months. Linear mixed models and Cox proportional-hazard regression models were used as appropriate.

RESULTS

Accelerated GrimAge, GrimAge2, FitAge and DunedinPACE at baseline were associated with increasing FI scores per year (adjusted-Beta ranged from 0.0015 to 0.0021, P < 0.05), and accelerated GrimAge and GrimAge2 were associated with an increased risk of incident FI-defined frailty (adjusted-HRs 1.43 and 1.39, respectively, P < 0.05). The association between DunedinPACE and the change in FI scores was stronger in females (adjusted-Beta 0.0029, P 0.001 than in males (adjusted-Beta 0.0002, P 0.81). DunedinPACE, but not the other AA measures, was also associated with worsening Fried scores (adjusted-Beta 0.0175, P 0.04). No associations were observed with persistent ADL disability.

CONCLUSION

Epigenetic AA in later life is associated with increasing frailty scores per year and the risk of incident FI-defined frailty.

Handling missing disease information due to death in diseases that need two visits to diagnose

In studies that assess disease status periodically, time of disease onset is interval censored between visits. Participants who die between two visits may have unknown disease status after their last visit. In this work, we consider an additional scenario where diagnosis requires two consecutive positive tests, such that disease status can also be unknown at the last visit preceding death. We show that this impacts the choice of censoring time for those who die without an observed disease diagnosis. We investigate two classes of models that quantify the effect of risk factors on disease outcome: a Cox proportional hazards model with death as a competing risk and an illness death model that treats disease as a possible intermediate state. We also consider four censoring strategies: participants without observed disease are censored at death (Cox model only), the last visit, the last visit with a negative test, or the second last visit. We evaluate the performance of model and censoring strategy combinations on simulated data with a binary risk factor and illustrate with a real data application. We find that the illness death model with censoring at the second last visit shows the best performance in all simulation settings. Other combinations show bias that varies in magnitude and direction depending on the differential mortality between diseased and disease-free subjects, the gap between visits, and the choice of the censoring time.

The association of allopurinol with persistent physical disability and frailty in a large community based older cohort

BACKGROUND

The protective effects of allopurinol on physical function in older adults are not well understood, despite its potential to improve functional gains and reduce sarcopenia. This study aims to determine the association between allopurinol, persistent physical disability, and frailty in older gout patients.

METHODS

This analysis used data from a randomized trial in an older cohort, ASPirin in Reducing Events in the Elderly (ASPREE). ASPREE recruited 19,114 participants aged ≥65 years without prior cardiovascular events, dementia, or independence-limiting physical disability at trial enrolment. This analysis examined the association of baseline and time-varying allopurinol use with persistent physical disability and new-onset frailty in participants with gout at baseline (self-report or use of any anti-gout medications). Frailty was measured using the Fried frailty phenotype (score ≥3/5) and a deficit accumulation frailty index (FI) (score >0.21/1.0). Multivariable Cox proportional-hazards models were used for main analyses.

RESULTS

This analysis included 1155 gout participants, with 630 taking allopurinol at baseline and 525 not. During a median follow-up of 5.7 years, 113 new allopurinol users were identified. Compared with nonusers, baseline allopurinol use was associated with a significant risk reduction of persistent physical disability (Adjusted HR 0.46, 95% CI 0.23-0.92, p = 0.03). The strength of the association was modestly attenuated in the time-varying analysis (Adjusted HR 0.56, 0.29-1.08, p = 0.08). No significant associations with frailty measures were observed for either baseline allopurinol use (Fried frailty: Adjusted HR 0.83, 0.62-1.12; FI: Adjusted HR 0.96, 0.74-1.24) or time-varying allopurinol use (Fried frailty: Adjusted HR 0.92, 0.69-1.24; FI: Adjusted HR 1.02, 0.78-1.33).

CONCLUSIONS

Allopurinol use in older adults with gout is associated with a reduced risk of persistent physical disability but not associated with risk of frailty.

The Association between Frailty and Dementia-Free and Physical Disability-Free Survival in Community-Dwelling Older Adults

INTRODUCTION

Frailty is a common geriatric syndrome that adversely impacts health outcomes. This study examined correlates of physical frailty in healthy community-dwelling older adults and studied the effect of frailty on disability-free survival (DFS), defined as survival free of independence-limiting physical disability or dementia.

METHODS

This is a post hoc analysis of 19,114 community-dwelling older adults (median age: 74.0 years, interquartile range or IQR: 6.1 years) from Australia and the USA enrolled in the "ASPirin in Reducing Events in the Elderly (ASPREE)" clinical trial. Frailty was assessed using a modified Fried phenotype and a deficit accumulation frailty index (FI) utilizing a ratio score derived from 66 items. Multinomial logistic regression was used to examine the correlates of frailty and Cox regression to analyze the association between frailty and DFS (and its components).

RESULTS

At study enrollment, 39.0% were prefrail, and 2.2% of participants were frail, according to Fried phenotype. Older age, higher waist circumference, lower education, ethnoracial origin, current smoking, depression, and polypharmacy were associated with prefrailty and frailty according to Fried phenotype and FI. Fried phenotype defined prefrailty and frailty predicted reduced DFS (prefrail: HR: 1.67; 95% CI: 1.50-1.86 and frail: HR: 2.80; 95% CI: 2.27-3.46), affecting each component of DFS including dementia, physical disability, and mortality. Effect sizes were larger, according to FI.

CONCLUSION

Our study showed that prefrailty is common in community-dwelling older adults initially free of cardiovascular disease, dementia, or independence-limiting physical disability. Prefrailty and frailty significantly reduced disability-free survival. Addressing modifiable correlates, like depression and polypharmacy, might reduce the adverse impact of frailty on dementia-free and physical disability-free survival.

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.

The effect of depressive symptoms on disability-free survival in healthy older adults: A prospective cohort study

BACKGROUND

Gerontology and ageing research are increasingly focussing on healthy life span (healthspan), the period of life lived free of serious disease and disability. Late-life depression (LLD) is believed to impact adversely on physical health. However, no studies have examined its effect on healthspan. This study investigated the effect of LLD and subthreshold depression on disability-free survival, a widely accepted measure of healthspan.

METHODS

This prospective cohort study used data from the ASPirin in Reducing Events in the Elderly study. Participants were aged ≥70 years (or ≥65 years for African-American and Hispanic participants) and free of dementia, physical disability and cardiovascular disease. Depressive symptoms were measured using the 10-item Centre for Epidemiological Studies Depression Scale (CES-D-10). LLD and subthreshold depression were defined as CES-D-10 scores ≥8 and 3-7, respectively. Disability-free survival was defined as survival free of dementia and persistent physical disability.

RESULTS

A total of 19,110 participants were followed up for a maximum of 7.3 years. In female participants, LLD was associated with lower disability-free survival adjusting for sociodemographic and lifestyle factors, medical comorbidities, polypharmacy, physical function and antidepressant use (HR, 1.50; 95% CI, 1.23-1.82). In male participants, LLD was associated with lower disability-free survival adjusting for sociodemographic and lifestyle factors (HR, 1.30; 95% CI, 1.03-1.64). Subthreshold depression was also associated with lower disability-free survival in both sexes.

CONCLUSIONS

LLD may be a common and important risk factor for shortened healthspan.

The Effect of Low-Dose Aspirin on Frailty Phenotype and Frailty Index in Community-Dwelling Older Adults in the ASPirin in Reducing Events in the Elderly Study

BACKGROUND

Frailty is associated with chronic inflammation, which may be modified by aspirin. The purpose of this study was to determine whether low-dose aspirin reduces incident frailty in healthy older adult participants of the ASPirin in Reducing Events in the Elderly (ASPREE) trial.

METHODS

In the United States and Australia, 19 114 community-dwelling individuals aged ≥70 and older (U.S. minorities ≥65 years) and free of overt cardiovascular disease, persistent physical disability, and dementia were enrolled in ASPREE, a double-blind, placebo-controlled trial of 100-mg daily aspirin versus placebo. Frailty, a prespecified study end point, was defined according to a modified Fried frailty definition (Fried frailty) and the frailty index based on the deficit accumulation model (frailty index). Competing risk Cox proportional hazard models were used to compare time to incident frailty by aspirin versus placebo. Sensitivity analysis was conducted to include frailty data with and without imputation of missing data.

RESULTS

Over a median 4.7 years, 2 252 participants developed incident Fried frailty, and 4 451 had incident frailty according to the frailty index. Compared with placebo, aspirin treatment did not alter the risk of incident frailty (Fried frailty hazard ratio [HR]: 1.04, 95% confidence interval [CI] 0.96-1.13; frailty index HR: 1.03, 95% CI 0.97-1.09). The proportion of individuals classified as frail, and the trajectory in continuous frailty scores over time, were not different between the aspirin and placebo treatment groups. The results were consistent across a series of subgroups.

CONCLUSIONS

Low-dose aspirin use in healthy older adults when initiated in older ages does not reduce risk of incident frailty or the trajectory of frailty.

Combination of gait speed and grip strength to predict cognitive decline and dementia

Introduction

To determine whether slowed gait and weakened grip strength independently, or together, better identify risk of cognitive decline or dementia.

Methods

Time to walk 3 meters and grip strength were measured in a randomized placebo-controlled clinical trial involving community-dwelling, initially cognitively healthy older adults (N = 19,114).

Results

Over a median 4.7 years follow-up, slow gait and weak grip strength at baseline were independently associated with risk of incident dementia (hazard ratio [HR] = 1.44, 95% confidence interval [CI]: 1.19-1.73; and 1.24, 95% CI: 1.04-1.50, respectively) and cognitive decline (HR = 1.38, 95% CI: 1.26-1.51; and 1.04, 95% CI: 0.95-1.14, respectively) and when combined, were associated with 79% and 43% increase in risk of dementia and cognitive decline, respectively. Annual declines in gait and in grip over time showed similar results.

Discussion

Gait speed and grip strength are low-cost markers that may be useful in the clinical setting to help identify and manage individuals at greater risk, or with early signs, of dementia, particularly when measured together.

Highlights

Grip strength and gait speed are effective predictors and markers of dementia.Dementia risk is greater than cognitive decline risk with declines in gait or grip.Decline in gait speed, more so than in grip strength, predicts greater dementia risk.Greater risk prediction results from combining grip strength and gait speed.

Brain-predicted age difference is associated with cognitive processing in later-life

Brain age is a neuroimaging-based biomarker of aging. This study examined whether the difference between brain age and chronological age (brain-PAD) is associated with cognitive function at baseline and longitudinally. Participants were relatively healthy, predominantly white community-dwelling older adults (n = 531, aged ≥70 years), with high educational attainment (61% ≥12 years) and socioeconomic status (59% ≥75th percentile). Brain age was estimated from T1-weighted magnetic resonance images using an algorithm by Cole et al., 2018. After controlling for age, gender, education, depression and body mass index, brain-PAD was negatively associated with psychomotor speed (Symbol Digit Modalities Test) at baseline (Bonferroni p < 0.006), but was not associated with baseline verbal fluency (Controlled Oral Word Association Test), delayed recall (Hopkins Learning Test Revised), or general cognitive status (Mini-Mental State Examination). Baseline brain-PAD was not associated with 3-year change in cognition (Bonferroni p > 0.006). These findings indicate that even in relatively healthy older people, accelerated brain aging is associated with worse psychomotor speed, but future longitudinal research into changes in brain-PAD is needed.

Long-Term Aspirin Use and Self-Reported Walking Speed in Older Men: The Physicians' Health Study

BACKGROUND

Mobility limitation is a component of frailty that shares a bidirectional relationship with cardiovascular disease (CVD). Data are limited on the role of established CVD prevention therapies, such as aspirin, for prevention of frailty and mobility limitation.

OBJECTIVES

Examine the association between long-term aspirin use and walking speed.

DESIGN, SETTING, PARTICIPANTS

Prospective cohort of 14,315 men who participated in the Physicians' Health Study I, a completed randomized controlled trial of aspirin (1982-1988), with extended post-trial follow-up.

MEASUREMENTS

Annual questionnaires collected data on aspirin use, lifestyle and other factors. Average annual aspirin use was categorized for each participant: ≤60 days/year and >60 days/year. Mobility was defined according to self-reported walking pace, categorized as: don't walk regularly (reference), easy/casual <2mph, normal ≥2-2.9mph, or brisk/very brisk ≥3mph. Propensity scoring balanced covariates between aspirin categories. Multinomial logistic regression models estimated odds of being in each self-reported walking category.

RESULTS

Mean age was 70±8 years; mean aspirin use 11 years. There were 2,056 (14.3%) participants who reported aspirin use ≤60 days/year. Aspirin use >60 days/year was associated with drinking alcohol, smoking, hypertension, heart disease and stroke, while ≤60 days/year was associated with anticoagulation use and bleeding history. In all, 13% reported not walking regularly, 12% walked <2 mph, 44% walked ≥2-2.9 mph, and 31% walked ≥3 mph. After propensity score adjustment, regular aspirin use was associated with a faster walking speed. Odds ratios (95% confidence intervals) were 1.16 (0.97 to 1.39), 1.24 (1.08 to 1.43), and 1.40 (1.21 to 1.63) for <2 mph, ≥2-2.9 mph and ≥3 mph, respectively, compared to not walking regularly (p-trend<0.001).

CONCLUSIONS

In this cohort of older men, long-term aspirin use is associated with a greater probability of faster walking speed later in life.

Aspirin in the Modern Era of Cardiovascular Disease Prevention

Aspirin’s antithrombotic effects have a long-established place in the prevention of cardiovascular disease (CVD), and its traditional use as a core therapy for secondary prevention of CVD is well recognized. However, with the advent of newer antiplatelet agents and an increasing understanding of aspirin’s bleeding risks, its role across the full spectrum of modern CVD prevention has become less certain. As a consequence, recent trials have begun investigating aspirin-free strategies in secondary prevention. For example, a contemporary metanalysis of trials that assessed P2Y₁₂ inhibitor monotherapy versus prolonged (≥ 12 months) dual antiplatelet therapy (which includes aspirin) after percutaneous coronary intervention reported a lower risk of major bleeding and no increase in stent thrombosis, all-cause mortality, myocardial infarction (MI), or stroke in the P2Y₁₂ monotherapy group.

In contrast to secondary prevention, aspirin’s role in primary prevention has always been more controversial. While historical trials reported a reduction in MI and stroke, more contemporary trials have suggested diminishing benefit for aspirin in this setting, with no reduction in hard outcomes, and some primary prevention trials have even indicated a potential for harm. In this review, we discuss how changing population demographics, enhanced control of lipids and blood pressure, changes in the definition of outcomes like MI, evolution of aspirin formulations, and updated clinical practice guidelines have all impacted the use of aspirin for primary and secondary CVD prevention.