Aspirin for Primary Prevention of Cardiovascular Events in Relation to Lipoprotein(a) Genotypes

BACKGROUND

The role of aspirin in reducing lipoprotein(a)-mediated atherothrombotic events in primary prevention is not established.

OBJECTIVES

This study sought to assess whether low-dose aspirin benefits individuals with elevated plasma lipoprotein(a)-associated genotypes in the setting of primary prevention.

METHODS

The study analyzed 12,815 genotyped individuals ≥70 years of age of European ancestry and without prior cardiovascular disease events enrolled in the ASPREE (ASPirin in Reducing Events in the Elderly) randomized controlled trial of 100 mg/d aspirin. We defined lipoprotein(a)-associated genotypes using rs3798220-C carrier status and quintiles of a lipoprotein(a) genomic risk score (LPA-GRS). We tested for interaction between genotypes and aspirin allocation in Cox proportional hazards models for incidence of major adverse cardiovascular events (MACE) and clinically significant bleeding. We also examined associations in the aspirin and placebo arms of the trial separately.

RESULTS

During a median 4.7 years (IQR: 3.6-5.7 years) of follow-up, 435 MACE occurred, with an interaction observed between rs3798220-C and aspirin allocation (P = 0.049). rs3798220-C carrier status was associated with increased MACE risk in the placebo group (HR: 1.90; 95% CI: 1.11-3.24) but not in the aspirin group (HR: 0.54; 95% CI: 0.17-1.70). High LPA-GRS (vs low) was associated with increased MACE risk in the placebo group (HR: 1.70; 95% CI: 1.14-2.55), with risk attenuated in the aspirin group (HR: 1.41; 95% CI: 0.90-2.23), but the interaction was not statistically significant. In all participants, aspirin reduced MACE by 1.7 events per 1,000 person-years and increased clinically significant bleeding by 1.7 events per 1,000 person-years. However, in the rs3798220-C and high LPA-GRS subgroups, aspirin reduced MACE by 11.4 and 3.3 events per 1,000 person-years respectively, without significantly increased bleeding risk.

CONCLUSIONS

Aspirin may benefit older individuals with elevated lipoprotein(a) genotypes in primary prevention.

Variation in Mean Arterial Pressure Increases Falls Risk in Elderly Physically Frail and Prefrail Individuals Treated With Antihypertensive Medication

BACKGROUND

Impaired cerebral blood flow has been associated with an increased risk of falls. Mean arterial pressure (MAP) and variability in MAP have been reported to affect cerebral blood flow but their relationships to the risk of falls have not previously been reported.

METHODS

Utilising data from the Aspirin in Reducing Events in the Elderly trial participants, we estimated MAP and variability in MAP, defined as within-individual SD of MAP from baseline and first 2 annual visits. The relationship with MAP was studied in 16 703 participants amongst whom 1539 falls were recorded over 7.3 years. Variability in MAP was studied in 14 818 of these participants who experienced 974 falls over 4.1 years. Falls were confined to those involving hospital presentation. Cox regression was used to calculate hazard ratio and 95% CI for associations with falls.

RESULTS

Long-term variability in MAP was not associated with falls except amongst frail or prefrail participants using antihypertensive medications. Within this group each 5 mm Hg increase in long-term variability in MAP increased the risk of falls by 16% (hazard ratio, 1.16 [95% CI, 1.02-1.33]). Amongst the antihypertensive drugs studied, beta-blocker monotherapy (hazard ratio, 1.93 [95% CI, 1.17-3.18]) was associated with an increased risk of falls compared with calcium channel blockers.

CONCLUSIONS

Higher levels of long-term variability in MAP increase the risk of serious falls in older frail and prefrail individuals taking antihypertensive medications. The observation that the relationship was limited to frail and prefrail individuals might explain some of the variability of previous studies linking blood pressure indices and falls.

B-Type Natriuretic Peptide and Long-Term Cardiovascular Mortality in Patients With Coronary Heart Disease

Background

The plasma concentration of B‐type natriuretic peptide (BNP) is a strong predictor of adverse cardiovascular events. The aim of this study was to determine whether the association between plasma BNP concentration and cardiovascular mortality is sustained or diminishes with increasing time after BNP is measured.

Methods and Results

Six thousand seven hundred forty patients with a history of myocardial infarction or unstable angina who participated in the LIPID (Long‐Term Intervention with Pravastatin in Ischemic Disease) trial had plasma BNP concentration measured at baseline and after 1 year. Associations with cardiovascular mortality were evaluated in landmark analyses 1 to <5, 5 to <10, and 10 to 16 years after randomization. There were 1640 cardiovascular deaths. The cardiovascular mortality rate increased progressively from 10.2 to 19.1 to 26.3/1000 patient‐years from 1 to <5, 5 to <10, and 10 to 16 years after baseline, respectively. The average of baseline and 1‐year BNP concentration was more strongly associated with cardiovascular mortality compared with baseline or 1‐year BNP only. The hazard ratio (HR) for cardiovascular death associated with each doubling of average BNP concentration was similar during years 1 to <5 (HR, 1.53 [95% CI, 1.44–1.63]), years 5 to <10 (HR, 1.52 [95% CI, 1.44–1.60]), and years 10–16 (HR, 1.43 [95% CI, 1.36–1.50]), P<0.0001 for all.

Conclusions

BNP concentration remains an independent predictor of cardiovascular mortality more than a decade after it is measured. Because of random variation in plasma concentrations, the average of >1 BNP measurement improves long‐term risk prediction.

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).

Common genetic variants do not predict recurrent events in coronary heart disease patients

Background

It is unclear whether genetic variants identified from single nucleotide polymorphisms (SNPs) strongly associated with coronary heart disease (CHD) in genome-wide association studies (GWAS), or a genetic risk score (GRS) derived from them, can help stratify risk of recurrent events in patients with CHD.

Methods

Study subjects were enrolled at the close-out of the LIPID randomised controlled trial of pravastatin vs placebo. Entry to the trial had required a history of acute coronary syndrome 3–36 months previously, and patients were in the trial for a mean of 36 months. Patients who consented to a blood sample were genotyped with a custom designed array chip with SNPs chosen from known CHD-associated loci identified in previous GWAS. We evaluated outcomes in these patients over the following 10 years.

Results

Over the 10-year follow-up of the cohort of 4932 patients, 1558 deaths, 898 cardiovascular deaths, 727 CHD deaths and 375 cancer deaths occurred. There were no significant associations between individual SNPs and outcomes before or after adjustment for confounding variables and for multiple testing. A previously validated 27 SNP GRS derived from SNPs with the strongest associations with CHD also did not show any independent association with recurrent major cardiovascular events.

Conclusions

Genetic variants based on individual single nucleotide polymorphisms strongly associated with coronary heart disease in genome wide association studies or an abbreviated genetic risk score derived from them did not help risk profiling in this well-characterised cohort with 10-year follow-up. Other approaches will be needed to incorporate genetic profiling into clinically relevant stratification of long-term risk of recurrent events in CHD patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02520-0.

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.

Prognostic Value of a Polygenic Risk Score for Coronary Heart Disease in Individuals Aged 70 Years and Older

BACKGROUND

The use of a polygenic risk score (PRS) to improve risk prediction of coronary heart disease (CHD) events has been demonstrated to have clinical utility in the general adult population. However, the prognostic value of a PRS for CHD has not been examined specifically in older populations of individuals aged ≥70 years, who comprise a distinct high-risk subgroup. The objective of this study was to evaluate the predictive value of a PRS for incident CHD events in a prospective cohort of older individuals without a history of cardiovascular events.

METHODS

We used data from 12 792 genotyped, healthy older individuals enrolled into the ASPREE trial (Aspirin in Reducing Events in the Elderly), a randomized double-blind placebo-controlled clinical trial investigating the effect of daily 100 mg aspirin on disability-free survival. Participants had no previous history of diagnosed atherothrombotic cardiovascular events, dementia, or persistent physical disability at enrollment. We calculated a PRS (meta-genomic risk score) consisting of 1.7 million genetic variants. The primary outcome was a composite of incident myocardial infarction or CHD death over 5 years.

RESULTS

At baseline, the median population age was 73.9 years, and 54.9% were female. In total, 254 incident CHD events occurred. When the PRS was added to conventional risk factors, it was independently associated with CHD (hazard ratio, 1.24 [95% CI, 1.08-1.42], P=0.002). The area under the curve of the conventional model was 70.53 (95% CI, 67.00-74.06), and after inclusion of the PRS increased to 71.78 (95% CI, 68.32-75.24, P=0.019), demonstrating improved prediction. Reclassification was also improved, as the continuous net reclassification index after adding PRS to the conventional model was 0.25 (95% CI, 0.15-0.28).

CONCLUSION

A PRS for CHD performs well in older people and improves prediction over conventional cardiovascular risk factors. Our study provides evidence that genomic risk prediction for CHD has clinical utility in individuals aged 70 years and older. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01038583.

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.

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.

Trajectories of physical health-related quality of life and the risk of incident cardiovascular disease events and all-cause mortality in older people

Study objective

The aim of this study was to identify whether physical component score (PCS) of health-related quality of life trajectories over 4.7-years predicted subsequent risk of incident fatal and non-fatal CVD events, and all-cause mortality.

Methods

This study included 16,871 community-dwelling people aged ≥65 years enrolled in the ASPREE (ASPirin in Reducing Events in the Elderly) trial. PCS was assessed annually using the SF-12 (version-2) over a median 4.7-years (i.e. from baseline (2010-2014) till June 2017). Incident CVD events and all-cause mortality occurring after June 2017 until the second-year after the end of the trial were considered. Growth mixture and logistic regression modelling were used.

Results

Four PCS trajectories were identified: high (66.5%), intermediate (13.3%), decline (13.8%), and low (6.5%), and there was subsequently a total of 406 (2.50%) incident CVD events, 197 (1.17%) fatal CVD, and 751 (4.45%) deaths. The declining PCS trajectory group had the highest risk of incident CVD (adjusted OR, 1.51; 95% CI 1.14, 1.99), while the low PCS trajectory group had the greatest risk of fatal CVD (adjusted OR, 1.74; 95%CI 1.06, 2.85) and all-cause mortality (adjusted OR, 1.83; 95%CI 1.40, 2.40). After further adjustment for the baseline PCS score, only the association between declining PCS trajectory and incident CVD (adjusted OR, 1.51; 95%CI 1.11, 2.07) remained.

Conclusion

Our study strengthens the importance of PCS as a predictive measure of CVD and all-cause mortality in older people and also highlights that a declining PCS trajectory could be considered an early predictor of future CVD events.

Mean Arterial Pressure and Risk of Falls Resulting in Hospital Presentation in Older Adults

Utilising data from the ASPirin in Reducing Events in the Elderly trial participants aged 70-years, we estimated MAP and variation in MAP defined as within-individual SD of MAP from baseline and first 2 annual visits. Falls were confined to those involving presentation to a hospital. Cox proportional hazards regression was used to calculate hazard ratio (HR) and 95% confidence interval (CI) for associations with falls. Amongst 16,703 participants (1,540 falls), MAP was not associated with falls irrespective of antihypertensive medication status (all: HR 1.00, 95% CI 0.99-1.01, not on antihypertensive: HR 1.01, 95% CI 0.99, 1.02, on antihypertensive: HR 1.01, 95% CI 0.99-1.02). Amongst 14,818 participants who remained in the study up to year 2 without falls, 1 unit escalation in MAP variability increased the risk (HR 1.01, 95% CI 1.00-1.03). Compared with those in the lowest tercile of variability, those in the middle or highest tercile of variability experienced an increased risk of falling (middle: HR 1.32, 95% CI 1.06-1.65; highest: HR 1.25, 95% CI 1.01-1.55). When stratified for antihypertensive medication status, those receiving diuretics (HR 1.18, 95% CI 1.00-1.39) or beta-blockers (HR 1.37, 95% CI 1.08-1.73) were at increased risk compared to those receiving renin-angiotensin-system acting agents. All results persisted after adjustment for multiple covariates. The association of diuretics and beta-blockers with falls remained significant even after excluding those with history of heart failure. Older community-dwelling adults with high variability in MAP are at increases risk of falls, particularly amongst those receiving beta-blockers or diuretics.

Using Health-Related Quality of Life to Identify the Incident Cardiovascular Disease Risk

Previous studies have revealed that poor health-related quality of life (HRQoL) is associated with a higher risk of hospital readmission and mortality in patients with cardiovascular disease (CVD). The association between HRQoL and incident CVD is still limited for general older people. This study explored the associations between baseline HRQoL and incident and fatal CVD in community-dwelling Australian and the United States older people enrolled in ASPREE clinical trial. A cohort of 19,106 individuals aged 65 to 98 years, who were initially free of CVD, dementia, or disability, were followed between March 2010 and June 2017. The SF-12 questionnaire was used to assess HRQoL, and the physical (PCS) and mental component scores (MCS) of SF-12 were derived using norm-based methods. Incident major adverse CVD events included fatal CVD (death due to atherothrombotic CVD), hospitalizations for heart failure, myocardial infarction or stroke. Analyses were performed using Cox proportional-hazard regression. Over a median 4.7 follow-up years, there were 922 incident CVD events, 203 fatal CVD events, 171 hospitalizations for heart failure, 355 fatal or nonfatal myocardial infarction and 403 fatal or nonfatal strokes. A 10-unit higher PCS, but not MCS, was associated with a lower risk of incident CVD (HR=0.86, 95%CI 0.79-0.92), hospitalization for heart failure (HR=0.72, 95%CI 0.60-0.85), and myocardial infarction (HR=0.85, 95%CI 0.75-0.96). Neither PCS nor MCS was associated with fatal CVD events or stroke. Physical HRQoL can be used in combination with clinical data to identify the incident CVD risk among community-dwelling older people.

Out-of-hospital cardiac arrest in elderly individuals

Background

Out-of-hospital cardiac arrest (OHCA) is associated with poor outcome, particularly in elderly people. Due to the shift in global demographics towards an ageing population, understanding risk factors for OHCA is essential for the development of primary prevention strategies. Thus, we aimed to identify predictors for OHCA in a large, community-dwelling cohort of elderly individuals.

Methods

We analyzed data from 11,156 participants enrolled in a randomized, placebo-controlled primary prevention trial, investigating the effect of low-dose aspirin in individuals aged 70 years or above. At baseline all participants had no prior cardiovascular disease events, dementia or major physical disability. OHCA events occurring within 5 years were identified by probabilistic data-linkage with a state-wide out-of-hospital cardiac arrest registry. Possible predictors included age, sex, anthropometric measures, conventional cardiovascular risk factors, renal function and frailty. To evaluate the association with OHCA, we performed univariable and multivariable Cox regression analyses. In exploratory analyses we also evaluated the effect of low-dose aspirin on OHCA events.

Results

In the cohort 54.7% were female and median age was 74.1 years (Interquartile Range [IQR] 71.8–77.7). During a median follow up time of 4.7 years (IQR 3.4–6.0) we recorded 67 OHCA events with presumed cardiac cause. The incidence rate was 1.07 per 1,000 person-years (95% Confidence-Interval [CI] 0.80–1.40). The mortality rate following OHCA was 91.2% (n=62). Univariable Cox regression analyses identified age, sex, weight, abdominal circumference, serum creatinine, diabetes, arterial hypertension, intake of antihypertensive medication and pre-frailty as predictors for the outcome. In multivariable Cox regression analyses we identified age (Hazard Ratio [HR] 1.06, CI 1.00–1.13), female sex (HR 0.49, CI 0.26–0.94) and pre-frailty (HR 1.92, CI 1.03–3.58) to be independent predictors (Table). In exploratory analyses there was no effect of low-dose aspirin on OHCA (HR 1.52, CI 0.87–2.70).

Conclusion

In a large, contemporary cohort of healthy, elderly individuals we describe a significant incidence of OHCA events associated with a very high mortality. We identified age, sex and pre-frailty, but interestingly not conventional cardiovascular risk factors as independent predictors of OHCA. We could not show a benefit of low-dose aspirin treatment, although the number of events was small. Our findings emphasize the importance of preventive strategies for pre-frailty in elderly individuals.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ASPREE study was primarily funded by the National Institute of Aging and National Cancer Institute at the National Institutes of Health (grant number U01AG029824), the Australian National Health & Medical Research Council (grants 334047 & 1127060), Monash University (Australia) and the Victorian Cancer Agency (Australia). Multivariable Cox regression analyses

Role of Cardiac Biomarkers in Epidemiology and Risk Outcomes

BACKGROUND

The use of biomarkers associated with cardiovascular disease (CVD) is established for diagnostic purposes. Cardiac troponins, as specific markers of myocardial injury, and natriuretic peptides, reflecting myocardial dilation, are routinely used for diagnosis in clinical practice. In addition, a substantial body of research has shed light on the ability of biomarkers to reflect the risk of future major cardiovascular events. Among biomarkers, troponin and members of the natriuretic peptide family have been investigated extensively in the general population, in those at higher risk, and in patients with known CVD. Both biomarkers have been shown to contribute substantially to statistical models describing cardiovascular risk, in addition to and independently of important clinical characteristics. The more precise identification of individuals at risk by appropriate use of biomarkers might lead to an earlier initiation of preventive therapies and potentially avoid significant events.

CONTENT

We summarize the current evidence concerning risk prediction using cardiac biomarkers at different stages in the development of CVD and provide examples of observational studies and large-scale clinical trials testing such application. Beyond the focus on troponin and natriuretic peptides, we also discuss other important and emerging biomarkers in the field with potential for such application, including growth differentiation factor-15, soluble ST2 (alias for IL1RL1 [interleukin 1 receptor like 1), and galectin-3.

SUMMARY

Incorporating biomarkers in risk prediction models might allow more precise identification of individuals at risk. Among the various biomarkers, cardiac troponin appears to be the most promising for prediction of future cardiovascular events in a wide variety of patient populations.

Long-Term Blood Pressure Variability and Risk of Cognitive Decline and Dementia Among Older Adults

Background

Blood pressure variability (BPV) in midlife increases risk of late‐life dementia, but the impact of BPV on the cognition of adults who have already reached older ages free of major cognitive deficits is unknown. We examined the risk of incident dementia and cognitive decline associated with long‐term, visit‐to‐visit BPV in a post hoc analysis of the ASPREE (Aspirin in Reducing Events in the Elderly) trial.

Methods and Results

ASPREE participants (N=19 114) were free of dementia and significant cognitive impairment at enrollment. Measurement of BP and administration of a standardized cognitive battery evaluating global cognition, delayed episodic memory, verbal fluency, and processing speed and attention occurred at baseline and follow‐up visits. Time‐to‐event analysis using Cox proportional hazards regression models were used to calculate hazard ratios (HR) and corresponding 95% CI for incident dementia and cognitive decline, according to tertile of SD of systolic BPV. Individuals in the highest BPV tertile compared with the lowest had an increased risk of incident dementia and cognitive decline, independent of average BP and use of antihypertensive drugs. There was evidence that sex modified the association with incident dementia (interaction P=0.02), with increased risk in men (HR, 1.68; 95% CI, 1.19–2.39) but not women (HR, 1.01; 95% CI, 0.72–1.42). For cognitive decline, similar increased risks were observed for men and women (interaction P=0.15; men: HR, 1.36; 95% CI, 1.16–1.59; women: HR, 1.14; 95% CI, 0.98–1.32).

Conclusions

High BPV in older adults without major cognitive impairment, particularly men, is associated with increased risks of dementia and cognitive decline.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01038583; isrctn.com. Identifier: ISRCTN83772183.

Effect of Statin Therapy on Cognitive Decline and Incident Dementia in Older Adults

BACKGROUND

The neurocognitive effect of statins in older adults remain uncertain.

OBJECTIVES

The aim of this study was to investigate the associations of statin use with cognitive decline and incident dementia among older adults.

METHODS

This analysis included 18,846 participants ≥65 years of age in a randomized trial of aspirin, who had no prior cardiovascular events, major physical disability, or dementia initially and were followed for 4.7 years. Outcome measures included incident dementia and its subclassifications (probable Alzheimer's disease, mixed presentations); mild cognitive impairment (MCI) and its subclassifications (MCI consistent with Alzheimer's disease, other MCI); and changes in domain-specific cognition, including global cognition, memory, language and executive function, psychomotor speed, and the composite of these domains. Associations of baseline statin use versus nonuse with dementia and MCI outcomes were examined using Cox proportional hazards models and with cognitive change using linear mixed-effects models, adjusting for potential confounders. The impact of statin lipophilicity on these associations was further examined, and effect modifiers were identified.

RESULTS

Statin use versus nonuse was not associated with dementia, MCI, or their subclassifications or with changes in cognitive function scores over time (p > 0.05 for all). No differences were found in any outcomes between hydrophilic and lipophilic statin users. Baseline neurocognitive ability was an effect modifier for the associations of statins with dementia (p for interaction < 0.001) and memory change (p for interaction = 0.02).

CONCLUSIONS

In adults ≥65 years of age, statin therapy was not associated with incident dementia, MCI, or declines in individual cognition domains. These findings await confirmation from ongoing randomized trials.

Predictive Performance of a Polygenic Risk Score for Incident Ischemic Stroke in a Healthy Older Population

[Figure: see text].

Development and validation of a ceramide- and phospholipid-based cardiovascular risk estimation score for coronary artery disease patients

AIMS

Distinct ceramide lipids have been shown to predict the risk for cardiovascular disease (CVD) events, especially cardiovascular death. As phospholipids have also been linked with CVD risk, we investigated whether the combination of ceramides with phosphatidylcholines (PCs) would be synergistic in the prediction of CVD events in patients with atherosclerotic coronary heart disease in three independent cohort studies.

METHODS AND RESULTS

Ceramides and PCs were analysed using liquid chromatography-mass spectrometry (LC-MS) in three studies: WECAC (The Western Norway Coronary Angiography Cohort) (N = 3789), LIPID (Long-Term Intervention with Pravastatin in Ischaemic Disease) trial (N = 5991), and KAROLA (Langzeiterfolge der KARdiOLogischen Anschlussheilbehandlung) (N = 1023). A simple risk score, based on the ceramides and PCs showing the best prognostic features, was developed in the WECAC study and validated in the two other cohorts. This score was highly significant in predicting CVD mortality [multiadjusted hazard ratios (HRs; 95% confidence interval) per standard deviation were 1.44 (1.28-1.63) in WECAC, 1.47 (1.34-1.61) in the LIPID trial, and 1.69 (1.31-2.17) in KAROLA]. In addition, a combination of the risk score with high-sensitivity troponin T increased the HRs to 1.63 (1.44-1.85) and 2.04 (1.57-2.64) in WECAC and KAROLA cohorts, respectively. The C-statistics in WECAC for the risk score combined with sex and age was 0.76 for CVD death. The ceramide-phospholipid risk score showed comparable and synergistic predictive performance with previously published CVD risk models for secondary prevention.

CONCLUSION

A simple ceramide- and phospholipid-based risk score can efficiently predict residual CVD event risk in patients with coronary artery disease.

Association of Statin Use With Disability-Free Survival and Cardiovascular Disease Among Healthy Older Adults

BACKGROUND

There is clinical uncertainty regarding the benefits and harms of prescribing statins in healthy subjects ≥70 years of age.

OBJECTIVES

The aim of this study was to examine the association among statins, dementia-free and disability-free survival, and cardiovascular disease (CVD) among healthy older adults using data from the ASPREE (Aspirin in Reducing Events in the Elderly) trial.

METHODS

ASPREE was a randomized trial of 19,114 community-dwelling persons in Australia and the United States ≥65 years of age and free of documented CVD, dementia, and disability. Data were collected for those ≥70 years of age, and participants who took statins at baseline were compared with those who did not using Cox proportional hazards regression with inverse probability weighting. The primary outcome, referred to as "disability-free survival," was a composite of all-cause mortality, dementia, or persistent physical disability. Other outcomes included the individual components of the composite outcome, major adverse cardiovascular events, fatal CVD, myocardial infarction, and stroke.

RESULTS

Of the 18,096 included participants (median age 74.2 years, 56.0% women), 5,629 took statins at baseline. Over a median follow-up period of 4.7 years, baseline statin use was not associated with disability-free survival or with the risk for all-cause mortality or dementia. However, it was associated with lower risks for physical disability and all cardiovascular outcomes.

CONCLUSIONS

Among healthy community-dwelling adults ≥70 years of age, statin use may be beneficial for preventing physical disability and CVD but not beneficial for prolonging disability-free survival or avoiding death or dementia. Future clinical trials are needed to confirm these findings.

Long-Term Blood Pressure Variability and Risk of Cardiovascular Disease Events Among Community-Dwelling Elderly

High office blood pressure variability (OBPV) in midlife increases the risk of cardiovascular disease (CVD), but the impact of OBPV in older adults without previous CVD is unknown. We conducted a post hoc analysis of ASPREE trial (Aspirin in Reducing Events in the Elderly) participants aged 70-years and older (65 for US minorities) without history of CVD events at baseline, to examine risk of incident CVD associated with long-term, visit-to-visit OBPV. CVD was a prespecified, adjudicated secondary end point in ASPREE. We estimated OBPV using within-individual SD of mean systolic BP from baseline and first 2 annual visits. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% CI for associations with CVD events. In 16 475 participants who survived to year 2 without events, those in the highest tertile of OBPV had increased risk of CVD events after adjustment for multiple covariates, when compared with participants in the lowest tertile (HR, 1.36 [95% CI, 1.08-1.70]; P=0.01). Similar increased risk was observed for ischemic stroke (HR, 1.56 [95% CI, 1.04-2.33]; P=0.03), heart failure hospitalization, or death (HR, 1.73 [95% CI, 1.07-2.79]; P=0.02), and all-cause mortality (HR, 1.27 [95% CI, 1.04-1.54]; P=0.02). Findings were consistent when stratifying participants by use of antihypertensive drugs, while sensitivity analyses suggested the increased risk was especially for individuals whose BP was uncontrolled during the OBPV estimation period. Our findings support increased OBPV as a risk factor for CVD events in healthy older adults with, or without hypertension, who have not had such events previously. Registration- URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01038583; URL: https://www.isrctn.com; Unique identifiers: ISRCTN83772183.

Fox K, Liang Y, Liu L, Zhu J, Pogosova N, Maggioni AP, Avezum A, Piegas LS, Keltai K, Keltai M, Berkowitz SD, Yusuf S. Rivaroxaban for Prevention of Covert Brain Infarcts and Cognitive Decline

Background and Purpose:

Covert brain infarcts are associated with cognitive decline. It is not known whether therapies that prevent symptomatic stroke prevent covert infarcts. COMPASS compared rivaroxaban with and without aspirin with aspirin for the prevention of stroke, myocardial infarction, and vascular death in participants with stable vascular disease and was terminated early because of benefits of rivaroxaban 2.5 mg twice daily plus aspirin over aspirin. We obtained serial magnetic resonance imagings and cognitive tests in a consenting subgroup of COMPASS patients to examine treatment effects on infarcts, cerebral microbleeds, and white matter hyperintensities.

Methods:

Baseline and follow-up magnetic resonance imagings were completed in 1445 participants with a mean (SD) interval of 2.0 (0.7) years. Whole-brain T1, T2 fluid-attenuated inversion recovery, T2* sequences were centrally interpreted by blinded, trained readers. Participants had serial measurements of cognition and function. The primary end point was the proportion of participants with incident covert infarcts. Secondary end points were the composite of clinical stroke and covert brain infarcts, cerebral microbleeds, and white matter hyperintensities.

Results:

At baseline, 493 (34.1%) participants had infarcts. Incident covert infarcts occurred in 55 (3.8%) participants. In the overall trial rivaroxaban plus aspirin reduced ischemic stroke by 49% (0.7% versus 1.4%; hazard ratio [95% CI], 0.51 [0.38–0.68]). In the magnetic resonance imaging substudy the effects of rivaroxaban+aspirin versus aspirin were: covert infarcts: 2.7% versus 3.5% (odds ratio [95% CI], 0.77 [0.37–1.60]); Covert infarcts or ischemic stroke: 2.9% versus 5.3% (odds ratio [95% CI], 0.53 [0.27–1.03]). Incident microbleeds occurred in 6.6% of participants and 65.7% of participants had an increase in white matter hyperintensities volume with no effect of treatment for either end point. There was no effect on cognitive tests.

Conclusions:

Covert infarcts were not significantly reduced by treatment with rivaroxaban and aspirin but estimates for the combination of ischemic stroke and covert infarcts were consistent with the effect on ischemic stroke in the overall trial.

Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01776424.