Testosterone and the risk of incident atrial fibrillation in older men: further analysis of the ASPREE study.

Background: A cardiovascular safety trial of testosterone in men with cardiovascular risk factors or disease found no difference in rates of major adverse cardiovascular events (MACE) or death but noted more atrial fibrillation (AF) events in testosterone-treated men. We investigated the relationship between endogenous testosterone concentrations with risk of developing AF in healthy older men. Methods: Post-hoc analysis of 4570 male participants in the ASPirin in Reducing Events in the Elderly (ASPREE) study. Men were aged ≥ 70 years, had no history of cardiovascular disease (including AF), thyroid disease, prostate cancer, dementia, or life-threatening illnesses. Risk of AF was modelled using Cox proportional hazards regression. Findings: Median (IQR) age was 73.7 (71.6-77.1) years and median (IQR) follow-up 4.4 (3.3-5.5) years, during which 286 men developed AF (15.3 per 1000 participant-years). Baseline testosterone was higher in men who developed incident AF compared men who did not [17.0 (12.4-21.2) vs 15.7 (12.2-20.0) nmol/L]. There was a non-linear association of baseline testosterone with incident AF. The risk for AF was higher in men with testosterone in quintiles (Q) 4&5 (Q4:Q3, HR = 1.91; 95%CI = 1.29-2.83 and Q5:Q3HR = 1.98; 95%CI = 1.33-2.94). Results were similar after excluding men who experienced MACE or heart failure during follow-up. Interpretation: Circulating testosterone concentrations within the high-normal range are independently associated with an increased risk of incident AF amongst healthy older men. This suggests that AF may be an adverse consequence of high-normal total testosterone concentrations. Funding: National Institute on Aging and National Cancer Institute at the National Institutes of Health; Australian Government (NHMRC, CSIRO); Monash University; and AlfredHealth.

Association of plasma high-density lipoprotein cholesterol level with risk of incident dementia: a cohort study of healthy older adults.

Background: Recent studies have reported associations between high plasma high-density lipoprotein cholesterol (HDL-C) levels and risk of all-cause mortality, age-related macular degeneration, sepsis and fractures, but associations with dementia risk remain unclear. To determine whether high plasma HDL-C levels are associated with increased incident dementia risk in initially-healthy older people. Methods: We conducted a post-hoc analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial; a double-blind, randomized, placebo-controlled trial of daily low-dose aspirin in healthy older people. ASPREE recruited 16,703 participants aged ≥70 years (from Australia) and 2411 participants aged ≥65 years (from the US) between 2010 and 2014. Participants had no diagnosed cardiovascular disease, dementia, physical disability, or life-threatening illness at enrolment and were cognitively healthy (3MS score ≥78). All-cause dementia was a primary trial endpoint, and determined by DSM-IV criteria. Cox regression was used to examine hazard ratios between HDL-C categories <40 mg/dL, 40-60 mg/dL (reference category), 60-80 mg/dL, and >80 mg/dL and dementia. Restricted cubic spline curves were used to determine nonlinear associations. Data analysis was performed from October 2022 to January 2023. Findings: Of the 18,668 participants, 850 (4.6%) cases of incident dementia were recorded over 6.3 (SD 1.8) years. Participants with high HDL-C (>80 mg/dL) had a 27% higher risk of dementia (HR 1.27, 95% CI 1.03, 1.58). Age stratified analyses demonstrated that the risk of incident dementia was higher in participants ≥75 years compared to participants <75 years (HR 1.42, 95% CI 1.10, 1.83 vs HR 1.02, 95% CI 0.68, 1.51). Associations remained significant after adjusting for covariates including age, sex, country of enrolment, daily exercise, education, alcohol consumption, weight change over time, non-HDL-C, HDL-C-PRS, and APOE genotype. Interpretation: In a population of initially-healthy older adults aged ≥75 years, high HDL-C levels were associated with increased risk of all-cause dementia. Funding: National Institutes of Health, USA; National Health and Medical Research Council Australia; Monash University (Melbourne, VIC, Australia); and the Victorian Cancer Agency (Australia).

The ASPREE Healthy Ageing Biobank: Methodology and participant characteristics.

ASPirin in Reducing Events in the Elderly (ASPREE), a placebo-controlled prevention trial of low dose aspirin, provided the opportunity to establish a biospecimen biobank from initially healthy persons aged 70+ years for future research. The ASPREE Healthy Ageing Biobank (ASPREE Biobank) collected, processed and stored blood and urine samples at -80degC or under nitrogen vapour at two timepoints, three years apart, from a willing subset of Australian ASPREE participants. Written informed consent included separate opt-in questions for biomarker and genetic testing. Fractionated blood and urine were aliquoted into multiple low-volume, barcoded cryotubes for frozen storage within 4 hours of collection. Specially designed and outfitted mobile laboratories provided opportunities for participation by people in regional and rural areas. Detailed, high quality demographic, physiological and clinical data were collected annually through the ASPREE trial. 12,219 participants contributed blood/urine at the first timepoint, 10,617 of these older adults provided 3-year follow-up samples, and an additional 1,712 provided saliva for DNA. The mean participant age was 74 years, 54% were female and 46% lived outside major cities. Despite geographical and logistical challenges, nearly 100% of blood/urine specimens were processed and frozen within 4 hours of collection into >1.4 million aliquots. After a median of 4.7 years, major clinical events among ASPREE Biobank participants included 332 with dementia, 613 with cardiovascular disease events, 1259 with cancer, 357 with major bleeds and 615 had died. The ASPREE Biobank houses and curates a large number of biospecimens collected prior to the clinical manifestations of major disease, and 3-year follow-up samples, all linked to high quality, extensive phenotypic information. This provides the opportunity to identify or validate diagnostic, prognostic and predictive biomarkers, and potentially study biological effectors, of ageing-related diseases or maintenance of older-age good health.

Sex-dependent associations of plasma high-density lipoprotein cholesterol and mortality risk in healthy older men and women: two prospective cohort studies.

The relationship between high plasma high-density lipoprotein cholesterol (HDL-C) and cause and mortality are not well established in healthy older people. This study examined the associations between HDL-C levels and mortality in initially healthy older men and women. This analysis included participants from the Aspirin in Reducing Events in the Elderly (ASPREE; n=18,668) trial and a matched cohort from the UK Biobank (UKB; n=62,849 ≥65 years). Cox regression was used to examine hazard ratios between HDL-C categories <1.03 mmol/L, 1.03-1.55 mmol/L (referent category), 1.55-2.07 mmol/L, and >2.07 mmol/L and all-cause, cancer, cardiovascular disease (CVD), and "non-cancer non-CVD" mortality. Genetic contributions were assessed using a polygenic score for HDL-C. Among ASPREE participants (aged 75±5 years), 1836 deaths occurred over a mean follow-up of 6.3±1.8 years. In men, the highest category of HDL-C levels was associated with increased risk of all-cause (HR 1.60, 95% CI 1.26-2.03), cancer (HR 1.37, 95% CI 0.96-2.00), and "non-cancer non-CVD" mortality (HR 2.35, 95% CI 1.41-3.42) but not CVD mortality (HR 1.08, 95% CI 0.60-1.94). The associations were replicated among UKB participants (aged 66.9±1.5 years), including 8739 deaths over a mean follow-up of 12.7±0.8 years. There was a non-linear association between HDL-C levels and all-cause and cause-specific mortality. The association between HDL-C levels and mortality was unrelated to variations in the HDL-C polygenic score. No significant association was found between HDL-C levels and mortality in women. Higher HDL-C levels are associated with increased risk from cancer and "non-cancer non-CVD" mortality in healthy older men but no such relationship was observed in women.

Low-Density-Lipoprotein Cholesterol and Mortality Outcomes Among Healthy Older Adults: A Post Hoc Analysis of ASPREE Trial.

BACKGROUND: The prognostic implication of cholesterol levels in older adults remains uncertain. This study aimed to examine the relationship between low-density-lipoprotein cholesterol (LDL-c) and mortality outcomes in older individuals. METHODS: This post hoc analysis examined the associations of LDL-c levels with mortality risks from all-cause, cardiovascular disease (CVD), cancer, and combined non-CVD/noncancer conditions in a cohort of individuals aged ≥65 years from the ASPirin in Reducing Events in the Elderly trial (NCT01038583). At baseline, participants had no diagnosed dementia, physical disability, or CVD, and were not taking lipid-lowering agents. Outcome analyses were performed using multivariable Cox models. RESULTS: We analyzed 12 334 participants (mean age: 75.2 years). Over a median 7-year follow-up, 1 250 died. Restricted cubic splines found a U-shaped relation for LDL-c and all-cause mortality, cancer mortality, and noncancer/non-CVE mortality (nadir: 3.3-3.4 mmol/L); the risk of CVD mortality was similar at LDL-c below 3.3 mmol/L and increased above 3.3 mmol/L. Similar trends were observed in analyses modeling LDL-c by quartiles. When modeling LDL-c as a continuous variable, the risk of all-cause mortality, cancer mortality, and noncancer/non-CVD mortality was decreased by 9%, 16%, and 18%, respectively, per 1-mmol/L higher LDL-c, and the risk of CVD mortality was increased by 19% per 1-mmol/L higher LDL-c. Reduced all-cause and non-CVD/noncancer mortality risks were only significant in males but not females (pinteraction < .05). CONCLUSIONS: There were U-shaped relationships between LDL-c and all-cause mortality, cancer mortality, and noncancer/non-CVD mortality in healthy older adults. Higher LDL-c levels were associated with an increased risk of CVD mortality. Future studies are warranted to confirm our results.

Association of a healthy lifestyle with mortality in older people.

BACKGROUND: Unhealthy lifestyle behaviours such as smoking, high alcohol consumption, poor diet or low physical activity are associated with morbidity and mortality. Public health guidelines provide recommendations for adherence to these four factors, however, their relationship to the health of older people is less certain. METHODS: The study involved 11,340 Australian participants (median age 7.39 [Interquartile Range (IQR) 71.7, 77.3]) from the ASPirin in Reducing Events in the Elderly study, followed for a median of 6.8 years (IQR: 5.7, 7.9). We investigated whether a point-based lifestyle score based on adherence to guidelines for a healthy diet, physical activity, non-smoking and moderate alcohol consumption was associated with subsequent all-cause and cause-specific mortality. RESULTS: In multivariable adjusted models, compared to those in the unfavourable lifestyle group, individuals in the moderate lifestyle group (Hazard Ratio (HR) 0.73 [95% CI 0.61, 0.88]) and favourable lifestyle group (HR 0.68 [95% CI 0.56, 0.83]) had lower risk of all-cause mortality. A similar pattern was observed for cardiovascular related mortality and non-cancer/non-cardiovascular related mortality. There was no association of lifestyle with cancer-related mortality. CONCLUSIONS: In a large cohort of initially healthy older people, reported adherence to a healthy lifestyle is associated with reduced risk of all-cause and cause-specific mortality. Adherence to all four lifestyle factors resulted in the strongest protection.

Expanded statistical analysis plan for legacy and long-term effects of aspirin in the ASPREE-XT observational follow-up study of participants in the ASPREE randomized trial.

The ASPREE randomized controlled trial (2010-2017) of 19,114 community-dwelling older adults without cardiovascular disease and significant disability compared daily 100mg aspirin to placebo. A total of 16,317 (93%) of 17,546 surviving and non-withdrawn participants agreed to continue regular study follow-up visits in the post-trial phase, named ASPREE-XT (2017-2024). We present a statistical analysis plan to underpin three main papers to report aspirin effects through to the fourth post-trial ASPREE-XT study visit with focus areas of: (1) death, dementia, and disability, (2) CVD events and bleeding, and (3) cancer. The focus of the plan is to estimate long-term (entire timespan of RCT plus post-trial) and legacy (post-trial period only) effects of aspirin in the setting of primary prevention for older individuals. Preliminary insights to these effects are presented that are based on data that has been reported to the study's observational study monitoring board however formal data lock is not expected until October 2023.

The Effects of Statins on Cardiovascular and Inflammatory Biomarkers in Primary Prevention: A Systematic Review and Meta-Analysis.

BACKGROUND: Statins are well-established for their treatment of cardiovascular disease (CVD) due to their cholesterol-lowering effects and potential anti-inflammatory properties. Although previous systematic reviews demonstrate that statins reduce inflammatory biomarkers in the secondary prevention of CVD, none examine their effects on cardiac and inflammatory biomarkers in a primary prevention setting. METHODS: We conducted a systematic review and meta-analysis to examine the effects of statins on cardiovascular and inflammatory biomarkers among individuals without established CVD. The biomarkers included are: cardiac troponin, N-terminal pro B-type natriuretic peptide (NT-proBNP), C-reactive protein (CRP), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), soluble vascular cell adhesion molecule (sVCAM), soluble intercellular adhesion molecule (sICAM), soluble E-selectin (sE-selectin) and endothelin-1 (ET-1). A literature search was performed through Ovid MEDLINE, Embase and CINAHL Plus for randomised controlled trials (RCTs) published up to June 2021. RESULTS: Overall, 35 RCTs with 26,521 participants were included in our meta-analysis. Data was pooled using random effects models presented as standardised mean differences (SMD) with 95% confidence intervals (CI). Combining 36 effect sizes from 29 RCTs, statin use resulted in a significant reduction in CRP levels (SMD -0.61; 95% CI -0.91, -0.32; P<0.001). This reduction was observed for both hydrophilic (SMD -0.39; 95% CI -0.62, -0.16; P<0.001) and lipophilic statins (SMD -0.65; 95% CI -1.01, -0.29; P<0.001). There were no significant changes in serum concentrations of cardiac troponin, NT-proBNP, TNF-α, IL-6, sVCAM, sICAM, sE-selectin and ET-1. CONCLUSION: This meta-analysis demonstrates that statin use reduces serum CRP levels in a primary prevention setting for CVD, with no clear effect on the other eight biomarkers studied.

Statins for extension of disability-free survival and primary prevention of cardiovascular events among older people: protocol for a randomised controlled trial in primary care (STAREE trial).

INTRODUCTION: The world is undergoing a demographic transition to an older population. Preventive healthcare has reduced the burden of chronic illness at younger ages but there is limited evidence that these advances can improve health at older ages. Statins are one class of drug with the potential to prevent or delay the onset of several causes of incapacity in older age, particularly major cardiovascular disease (CVD). This paper presents the protocol for the STAtins in Reducing Events in the Elderly (STAREE) trial, a randomised double-blind placebo-controlled trial examining the effects of statins in community dwelling older people without CVD, diabetes or dementia. METHODS AND ANALYSIS: We will conduct a double-blind, randomised placebo-controlled trial among people aged 70 years and over, recruited through Australian general practice and with no history of clinical CVD, diabetes or dementia. Participants will be randomly assigned to oral atorvastatin (40 mg daily) or matching placebo (1:1 ratio). The co-primary endpoints are disability-free survival defined as survival-free of dementia and persistent physical disability, and major cardiovascular events (cardiovascular death or non-fatal myocardial infarction or stroke). Secondary endpoints are all-cause death, dementia and other cognitive decline, persistent physical disability, fatal and non-fatal myocardial infarction, fatal and non-fatal stroke, heart failure, atrial fibrillation, fatal and non-fatal cancer, all-cause hospitalisation, need for permanent residential care and quality of life. Comparisons between assigned treatment arms will be on an intention-to-treat basis with each of the co-primary endpoints analysed separately in time-to-first-event analyses using Cox proportional hazards regression models. ETHICS AND DISSEMINATION: STAREE will address uncertainties about the preventive effects of statins on a range of clinical outcomes important to older people. Institutional ethics approval has been obtained. All research outputs will be disseminated to general practitioner co-investigators and participants, published in peer-reviewed journals and presented at national and international conferences. TRIAL REGISTRATION NUMBER: NCT02099123.

Associations of Change in Body Size With All-Cause and Cause-Specific Mortality Among Healthy Older Adults.

Importance: The association between weight change and subsequent cause-specific mortality among older adults is not well described. The significance of changes in waist circumference (WC) has also not been compared with weight change for this purpose. Objective: To examine the associations of changes in body weight and WC with all-cause and cause-specific mortality. Design, Setting, and Participants: This cohort study is a post hoc analysis of data from the Aspirin in Reducing Events in the Elderly (ASPREE) randomized clinical trial, which recruited participants between March 1, 2010, and December 31, 2014. The study included community-based older adults (16 703 Australian participants aged ≥70 years and 2411 US participants aged ≥65 years) without evident cardiovascular disease (CVD), dementia, physical disability, or life-limiting chronic illness. Data analysis was performed from April to September 2022. Exposures: Body weight and WC were measured at baseline and at annual visit 2. Analysis models were adjusted for baseline body mass index because height and weight were measured at baseline, allowing for calculation of body mass index and other variables. Both body weight and WC changes were categorized as change within 5% (stable), decrease by 5% to 10%, decrease by more than 10%, increase by 5% to 10%, and increase by more than 10%. Main Outcomes and Measures: All-cause, cancer-specific, CVD-specific, and noncancer non-CVD-specific mortality. Mortality events were adjudicated by an expert review panel. Cox proportional hazards regression and competing risk analyses were used to calculate hazard ratios (HRs) and 95% CIs. Results: Among 16 523 participants (mean [SD] age, 75.0 [4.3] years; 9193 women [55.6%]), 1256 deaths were observed over a mean (SD) of 4.4 (1.7) years. Compared with men with stable weight, those with a 5% to 10% weight loss had a 33% higher (HR, 1.33; 95% CI, 1.07-1.66) risk of all-cause mortality, and those with more than a 10% decrease in body weight had a 289% higher (HR, 3.89; 95% CI, 2.93-5.18) risk. Compared with women with stable weight, those with a 5% to 10% weight loss had a 26% higher (HR, 1.26; 95% CI, 1.00-1.60) risk of all-cause mortality, and those with more than a 10% decrease in body weight had a 114% higher (HR, 2.14; 95% CI, 1.58-2.91) risk. Weight loss was associated with a higher cancer-specific mortality (>10% decrease among men: HR, 3.49; 95% CI, 2.26-5.40; 5%-10% decrease among women: HR, 1.44; 95% CI, 1.46-2.04; >10% decrease among women: HR, 2.78; 95% CI, 1.82-4.26), CVD-specific mortality (>10% decrease among men: HR, 3.14; 95% CI, 1.63-6.04; >10% decrease among women: HR, 1.92; 95% CI, 1.05-3.51), and noncancer non-CVD-specific mortality (>10% decrease among men: HR, 4.98; 95% CI, 3.14-7.91). A decrease in WC was also associated with mortality. Conclusions and Relevance: This cohort study of healthy older adults suggests that weight loss was associated with an increase in all-cause and cause-specific mortality, including an increased risk of cancer, CVD, and other life-limiting conditions. Physicians should be aware of the significance of weight loss, especially among older men.

Associations of body size with all-cause and cause-specific mortality in healthy older adults.

In the general population, body mass index (BMI) and waist circumference are recognized risk factors for several chronic diseases and all-cause mortality. However, whether these associations are the same for older adults is less clear. The association of baseline BMI and waist circumference with all-cause and cause-specific mortality was investigated in 18,209 Australian and US participants (mean age: 75.1 ± 4.5 years) from the ASPirin in Reducing Events in the Elderly (ASPREE) study, followed up for a median of 6.9 years (IQR: 5.7, 8.0). There were substantially different relationships observed in men and women. In men, the lowest risk of all-cause and cardiovascular mortality was observed with a BMI in the range 25.0-29.9 kg/m2 [HR25-29.9 vs 21-24.9 kg/m2: 0.85; 95% CI, 0.73-1.00] while the highest risk was in those who were underweight [HRBMI <21 kg/m2 vs BMI 21-24.9 kg/m2: 1.82; 95% CI 1.30-2.55], leading to a clear U-shaped relationship. In women, all-cause mortality was highest in those with the lowest BMI leading to a J-shaped relationship (HRBMI <21 kg/m2 vs BMI 21-24.9 kg/m2: 1.64; 95% CI 1.26-2.14). Waist circumference showed a weaker relationship with all-cause mortality in both men and women. There was little evidence of a relationship between either index of body size and subsequent cancer mortality in men or women, while non-cardiovascular non-cancer mortality was higher in underweight participants. For older men, being overweight was found to be associated with a lower risk of all-cause mortality, while among both men and women, a BMI in the underweight category was associated with a higher risk. Waist circumference alone had little association with all-cause or cause-specific mortality risk.Trial registration ASPREE https://ClinicalTrials.gov number NCT01038583.

Association of a Healthy Lifestyle with Mortality in Older People.

Background: Unhealthy lifestyle behaviours such as smoking, high alcohol consumption, poor diet or low physical activity are associated with morbidity and premature mortality. Public health guidelines provide recommendations for adherence to these four factors, however, their impact on the health of older people is less certain. Methods: The study involved 11,340 Australian participants (median age 7.39 [Interquartile Range (IQR) 71.7, 77.3]) from the ASPirin in Reducing Events in the Elderly study, followed for a median of 6.8 years (IQR: 5.7, 7.9). We investigated whether a point-based lifestyle score based on adherence to guidelines for a healthy diet, physical activity, non-smoking and moderate alcohol consumption was associated with all-cause and cause-specific mortality. Results: In multivariable adjusted models, compared to those in the unfavourable lifestyle group, individuals in the moderate lifestyle group (Hazard Ratio (HR) 0.73 [95% CI 0.61, 0.88]) and favourable lifestyle group (HR 0.68 [95% CI 0.56, 0.83]) had lower risk of all-cause mortality. A similar pattern was observed for cardiovascular related mortality and non-cancer/non-cardiovascular related mortality. There was no association of lifestyle with cancer-related mortality. Stratified analysis indicated larger effect sizes among males, those ≤ 73 years old and among those in the aspirin treatment group. Conclusions: In a large cohort of initially healthy older people, reported adherence to a healthy lifestyle is associated with reduced risk of all-cause and cause-specific mortality.

Association between popliteal artery wall thickness and structural progression in patients with symptomatic knee osteoarthritis.

OBJECTIVE: There is increasing evidence for the involvement of vascular disease in the pathogenesis of knee OA. Popliteal artery wall thickness can be used as a surrogate marker of atherosclerosis. We examined the association between popliteal artery wall thickness and knee cartilage volume in individuals with symptomatic knee OA. METHODS: This prospective cohort study analysed 176 participants from a randomized placebo-controlled trial examining the effect of atorvastatin on structural progression in knee OA. The participants underwent MRI of the study knee at baseline and 2-year follow-up. Popliteal artery wall thickness and tibial cartilage volume were measured from MRI using validated methods. The top quartile of the rate of tibial cartilage volume loss was defined as rapid progression. RESULTS: At baseline, every 10% increase in popliteal artery wall thickness was associated with 120.8 mm3 (95% CI 5.4, 236.2, P = 0.04) lower of medial tibial cartilage volume and 151.9 mm3 (95% CI 12.1, 291.7, P = 0.03) lower of lateral tibial cartilage volume. Longitudinally, for every 10% increase in popliteal artery wall thickness, the annual rate of medial tibial cartilage volume loss was increased by 1.14% (95% CI 0.09%, 2.20%, P = 0.03), and there was a 2.28-fold (95% CI 1.07, 4.83, P = 0.03) risk of rapid progression of medial tibial cartilage loss, adjusted for age, sex, BMI, tibial bone area, smoking, vigorous physical activity, and intervention group allocation. CONCLUSION: The findings support a role for vascular pathology in the progression of knee OA. Targeting atherosclerosis has the potential to improve outcomes in knee OA.

Examining evidence of time-dependent treatment effects: an illustration using regression methods.

BACKGROUND: For the design and analysis of clinical trials with time-to-event outcomes, the Cox proportional hazards model and the logrank test have been the cornerstone methods for many decades. Increasingly, the key assumption of proportionality-or time-fixed effects-that underpins these methods has been called into question. The availability of novel therapies with new mechanisms of action and clinical trials of longer duration mean that non-proportional hazards are now more frequently encountered. METHODS: We compared several regression-based methods to model time-dependent treatment effects. For illustration purposes, we used selected endpoints from a large, community-based clinical trial of low dose daily aspirin in older persons. Relative and absolute estimands were defined, and analyses were conducted in all participants. Additional exploratory analyses were undertaken by selected subgroups of interest using interaction terms in the regression models. DISCUSSION: In the trial with median 4.7 years follow-up, we found evidence for non-proportionality and a time-dependent treatment effect of aspirin on cancer mortality not previously reported in trial findings. We also found some evidence of time-dependence to an aspirin by age interaction for major adverse cardiovascular events. For other endpoints, time-fixed treatment effect estimates were confirmed as appropriate. CONCLUSIONS: The consideration of treatment effects using both absolute and relative estimands enhanced clinical insights into potential dynamic treatment effects. We recommend these analytical approaches as an adjunct to primary analyses to fully explore findings from clinical trials.

Prediction of disability-free survival in healthy older people.

Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disability-free survival outcome was defined as absence of dementia, persistent disability or death. Selection of potential predictors from amongst 25 biomedical, psychosocial and lifestyle variables including recognized geriatric risk factors, utilizing a machine-learning approach. Separate models were developed for men and women. The selected predictors were evaluated in a multivariable Cox proportional hazards model and validated internally by bootstrapping. We included 19,114 Australian and US participants aged ≥65 years (median 74 years, IQR 71.6-77.7). Common predictors of a worse prognosis in both sexes included higher age, lower Modified Mini-Mental State Examination score, lower gait speed, lower grip strength and abnormal (low or elevated) body mass index. Additional risk factors for men included current smoking, and abnormal eGFR. In women, diabetes and depression were additional predictors. The biased-corrected areas under the receiver operating characteristic curves for the final prognostic models at 5 years were 0.72 for men and 0.75 for women. Final models showed good calibration between the observed and predicted risks. We developed a prediction model in which age, cognitive function and gait speed were the strongest predictors of disability-free survival in healthy older people.Trial registration Clinicaltrials.gov (NCT01038583).

Associations between blood sex steroid concentrations and risk of major adverse cardiovascular events in healthy older women in Australia: a prospective cohort substudy of the ASPREE trial.

BACKGROUND: Blood testosterone concentrations in women decline during the reproductive years and reach a nadir in the seventh decade, after which concentrations increase and are restored to those of reproductive-aged women early in the eighth decade. We aimed to establish the association between the concentration of testosterone in the blood and risk of major adverse cardiovascular events (MACE) and all-cause mortality in healthy older women. METHODS: SHOW was a prospective cohort substudy of the longitudinal randomised ASPREE trial. Eligible participants were women aged at least 70 years from Australia with unimpaired cognition, no previous MACE, and a life expectancy of at least 5 years. Participants who were receiving hormonal or steroid therapy were ineligible for inclusion. We measured serum concentrations of sex steroids with liquid chromatography-tandem mass spectrometry and of SHBG with immunoassay. We compared lower concentrations of sex hormones with higher concentrations using four quartiles. Primary endpoints were risk of MACE and all-cause mortality, the associations of which with sex steroid concentrations were assessed using Cox proportional hazards regression that included age, body-mass index, smoking status, alcohol consumption, diabetes, hypertension, dyslipidaemia, impaired renal function, and treatment allocation in the ASPREE trial (aspirin vs placebo). ASPREE is registered with ClinicalTrials.gov, NCT01038583. FINDINGS: Of the 9180 women recruited to the ASPREE trial between March 10, 2010, and Dec 31 2014, 6358 participants provided sufficient biobank samples at baseline and 5535 were included in the final analysis. Median age at entry was 74·0 years (IQR 71·7-77·7). During a median 4·4 years of follow-up (24 553 person-years), 144 (2·6%) women had a first MACE (incidence 5·9 per 1000 person-years). During a median 4·6 years of follow-up (3·8-5·6), 200 women died (7·9 per 1000 person-years). In the fully adjusted models, higher concentrations of testosterone were associated with a lower incidence of MACE (quartile 4 vs quartile 1: hazard ratio 0·57 [95% CI 0·36-0·91]; p=0·02), as were higher concentrations of DHEA (quartile 4 vs quartile 1: 0·61 [0·38-0·97]; p=0·04). For oestrone, a lower risk of MACE was seen for concentrations in quartile 2 only, compared with quartile 1 (0·55 [0·33-0·92]; p=0·02). In fully adjusted models, no association was seen between SHBG and MACE, or between any hormone or SHBG and all-cause mortality. INTERPRETATION: Blood concentrations of testosterone and DHEA above the lowest quartile in older women were associated with a reduced risk of a first-ever MACE. Given that the physiological effects of DHEA are mediated through its steroid metabolites, if the current findings were to be replicated, trials investigating testosterone therapy for the primary prevention of ischaemic cardiovascular disease events in older women would be warranted. FUNDING: The National Health and Medical Research Council of Australia, US National Institute on Aging, the Victorian Cancer Agency, the Commonwealth Scientific and Industrial Research Organisation, and Monash University.

A multistate model of health transitions in older people: a secondary analysis of ASPREE clinical trial data.

BACKGROUND: Understanding the nature of transitions from a healthy state to chronic diseases and death is important for planning health-care system requirements and interventions. We aimed to quantify the trajectories of disease and disability in a population of healthy older people. METHODS: We conducted a secondary analysis of data from the ASPREE trial, which was done in 50 sites in Australia and the USA and recruited community-dwelling, healthy individuals who were aged 70 years or older (≥65 years for Black and Hispanic people in the USA) between March 10, 2010, and Dec 24, 2014. Participants were followed up with annual face-to-face visits, biennial assessments of cognitive function, and biannual visits for physical function until death or June 12, 2017, whichever occurred first. We used multistate models to examine transitions from a healthy state to first intermediate disease events (ie, cancer events, stroke events, cardiac events, and physical disability or dementia) and, ultimately, to death. We also examined the effects of age and sex on transition rates using Cox proportional hazards regression models. FINDINGS: 19 114 participants with a median age of 74·0 years (IQR 71·6-77·7) were included in our analyses. During a median follow-up of 4·7 years (IQR 3·6-5·7), 1933 (10·1%) of 19 114 participants had an incident cancer event, 487 (2·5%) had an incident cardiac event, 398 (2·1%) had an incident stroke event, 924 (4·8%) developed persistent physical disability or dementia, and 1052 (5·5%) died. 15 398 (80·6%) individuals did not have any of these events during follow-up. The highest proportion of deaths followed incident cancer (501 [47·6%] of 1052) and 129 (12·3%) participants transitioned from disability or dementia to death. Among 12 postulated transitions, transitions from the intermediate states to death had much higher rates than transitions from a healthy state to death. The progression rates to death were 158 events per 1000 person-years (95% CI 144-172) from cancer, 112 events per 1000 person-years (86-145) from stroke, 88 events per 1000 person-years (68-111) from cardiac disease, 69 events per 1000 person-years (58-82) from disability or dementia, and four events per 1000 person-years (4-5) from a healthy state. Age was significantly associated with an accelerated rate for most transitions. Male sex (vs female sex) was significantly associated with an accelerate rate for five of 12 transitions. INTERPRETATION: We describe a multistate model in a healthy older population in whom the most common transition was from a healthy state to cancer. Our findings provide unique insights into the frequency of events, their transition rates, and the impact of age and sex. These results have implications for preventive health interventions and planning for appropriate levels of residential care in healthy ageing populations. FUNDING: The National Institutes of Health.

Circulating Cystatin C Is an Independent Risk Marker for Cardiovascular Outcomes, Development of Renal Impairment, and Long-Term Mortality in Patients With Stable Coronary Heart Disease: The LIPID Study.

Background Elevated plasma cystatin C levels reflect reduced renal function and increased cardiovascular risk. Less is known about whether the increased risk persists long-term or is independent of renal function and other important biomarkers. Methods and Results Cystatin C and other biomarkers were measured at baseline (in 7863 patients) and 1 year later (in 6106 patients) in participants in the LIPID (Long-Term Intervention with Pravastatin in Ischemic Disease) study, who had a previous acute coronary syndrome. Outcomes were ascertained during the study (median follow-up, 6 years) and long-term (median follow-up, 16 years). Glomerular filtration rate (GFR) was estimated using Chronic Kidney Disease Epidemiology Collaboration equations (first GFR-creatinine, then GFR-creatinine-cystatin C). Over 6 years, in fully adjusted multivariable time-to-event models, with respect to the primary end point of coronary heart disease mortality or nonfatal myocardial infarction, for comparison of Quartile 4 versus 1 of baseline cystatin C, the hazard ratio was 1.37 (95% CI, 1.07-1.74; P=0.01), and for major cardiovascular events was 1.47 (95% CI, 1.19-1.82; P<0.001). Over 16 years, the association of baseline cystatin C with coronary heart disease, cardiovascular, and all-cause mortality persisted (each P<0.001) and remained significant after adjustment for estimated GFR-creatinine-cystatin C. Cystatin C also predicted the development of chronic kidney disease for 6 years (odds ratio, 6.61; 95% CI, 4.28-10.20) independently of estimated GFR-creatinine and other risk factors. However, this association was no longer significant after adjustment for estimated GFR-creatinine-cystatin C. Conclusions Cystatin C independently predicted major cardiovascular events, development of chronic kidney disease, and cardiovascular and all-cause mortality. Prediction of long-term mortality was independent of improved estimation of GFR. Registration URL: https://anzctr.org.au; Unique identifier: ACTRN12616000535471.

Trajectories of depressive symptoms in older adults and associated health outcomes.

With the progressive aging of the world's population, prolongation of a healthy lifespan in old age has become a medical research priority. The presence of depressive symptoms in later life is associated with poor health prognosis and increased mortality1,2. Here we explore distinct trajectories of depressive symptoms in later life and their association with several health-related outcomes in 19,110 older individuals followed for a median of 4.7 years. Using a latent class, mixed-modeling approach we identified four distinct trajectories of depressive symptoms with scoring patterns of consistently low, moderate, emerging and persistently high. Compared to those with minimal depressive symptoms, membership of any other class was associated with specific patterns of baseline sociodemographic and medical factors. Membership of any group with depressive symptoms was associated with a higher likelihood of health events, including physical disability, cancer and major bleeding episodes. Membership of the persistently depressed class was associated with increased mortality, while a diagnosis of dementia was generally limited to the class with initially low and progressively rising symptoms. The course of depressive symptoms in older individuals can vary widely and depend on several factors. The presence of depressive symptoms, including those that do not meet criteria for major depression, can flag a poor prognosis and risk for specific health conditions. Systematic assessment of depressive symptoms may facilitate early identification of at-risk populations.

Cardiovascular risk prediction in healthy older people.

Identification of individuals with increased risk of major adverse cardiovascular events (MACE) is important. However, algorithms specific to the elderly are lacking. Data were analysed from a randomised trial involving 18,548 participants ≥ 70 years old (mean age 75.4 years), without prior cardiovascular disease events, dementia or physical disability. MACE included coronary heart disease death, fatal or nonfatal ischaemic stroke or myocardial infarction. Potential predictors tested were based on prior evidence and using a machine-learning approach. Cox regression analyses were used to calculate 5-year predicted risk, and discrimination evaluated from receiver operating characteristic curves. Calibration was also assessed, and the findings internally validated using bootstrapping. External validation was performed in 25,138 healthy, elderly individuals in the primary care environment. During median follow-up of 4.7 years, 594 MACE occurred. Predictors in the final model included age, sex, smoking, systolic blood pressure, high-density lipoprotein cholesterol (HDL-c), non-HDL-c, serum creatinine, diabetes and intake of antihypertensive agents. With variable selection based on machine-learning, age, sex and creatinine were the most important predictors. The final model resulted in an area under the curve (AUC) of 68.1 (95% confidence intervals 65.9; 70.4). The model had an AUC of 67.5 in internal and 64.2 in external validation. The model rank-ordered risk well but underestimated absolute risk in the external validation cohort. A model predicting incident MACE in healthy, elderly individuals includes well-recognised, potentially reversible risk factors and notably, renal function. Calibration would be necessary when used in other populations.