Effect of Low-Dose Aspirin on the Course of Age-Related Macular Degeneration: A Secondary Analysis of the ASPREE Randomized Clinical Trial

Importance

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in old age. There is no proven intervention to prevent AMD and, apart from lifestyle, nutritional, and supplement advice, there is no intervention to delay its progression.

Objective

To determine the impact of long-term low-dose aspirin on the incidence and progression of AMD.

Design, Setting and Participants

The Aspirin in Reducing Events in the Elderly-AMD (ASPREE-AMD) study was an Australian-based substudy of the ASPREE trial, a multicenter, international, randomized, double-masked, placebo-clinical trial investigating the efficacy of low-dose aspirin in prolonging disability-free survival among older individuals. Retinal photography was conducted at baseline from March 2010 to January 2015, then 3 and 5 years after randomization. AMD status was determined using color retinal images and treatment records. Australian participants in ASPREE aged 70 years and older without dementia, independence-limiting physical disability, cardiovascular disease, or chronic illness limiting 5-year survival and with gradable retinal images at baseline were included. Data were analyzed from December 2022 to December 2023.

Interventions

Aspirin (100 mg daily, enteric coated) or placebo.

Main Outcomes and Measures

Incidence of AMD and progression from early/intermediate to late AMD. Outcomes were analyzed by modified intention-to-treat analysis.

Results

A total of 4993 participants were enrolled in this substudy. Baseline characteristics were similar between groups. At the time of sponsor-determined trial termination, retinal follow-up data were available for 3208 participants, 3171 of whom were analyzed for AMD incidence and progression, with a median (IQR) age of 73.5 (71.5-76.4) years and even sex distribution (1619 [51%] female). Median (IQR) follow-up time was 3.1 (3.0-3.5) years. Cumulative AMD incidence was 195 of 1004 (19.4%) in the aspirin group and 187 of 979 (19.1%) in the placebo group (relative risk [RR], 1.02; 95% CI, 0.85-1.22; P = .86). Cumulative progression from early/intermediate AMD to late AMD was observed in 14 of 615 (2.3%) participants in the aspirin group and 18 of 573 (3.1%) in the placebo group (RR, 0.72; 95% CI, 0.36-1.44; P = .36).

Conclusions and Relevance

In this trial, low-dose aspirin administered for 3 years did not affect the incidence of AMD. The evidence was weaker for progression of AMD due to low number of progressed cases. Overall, these results do not support suggestion that low-dose daily aspirin prevents the development or progression of AMD.

Trial Registration

anzctr.org Identifier: ACTRN12613000755730.

Correlation of extent of left ventricular endocardial unipolar low-voltage zones with ventricular tachycardia in nonischemic cardiomyopathy

BACKGROUND

Endocardial electrogram (EGM) characteristics in nonischemic cardiomyopathy (NICM) have not been explored adequately for prognostication.

OBJECTIVE

We aimed to study correlation of bipolar and unipolar EGM characteristics with left ventricular ejection fraction (LVEF) and ventricular tachycardia (VT) in NICM.

METHODS

Electroanatomic mapping of the left ventricle was performed. EGM characteristics were correlated with LVEF. Differences between groups with and without VT and predictors of VT were studied.

RESULTS

In 43 patients, unipolar EGM variables had better correlation with baseline LVEF than bipolar EGM variables: unipolar voltage (r = +0.36), peak negative unipolar voltage (r = -0.42), peak positive unipolar voltage (r = +0.38), and percentage area of unipolar low-voltage zone (LVZ; r = -0.41). Global mean unipolar voltage (hazard ratio [HR], 0.4; 95% confidence interval [CI], 0.2-0.8), extent of unipolar LVZ (HR, 1.6; 95% CI, 1.1-2.3), and percentage area of unipolar LVZ (HR, 1.6; 95% CI, 1.1-2.3) were significant predictors of VT. For classification of patients with VT, extent of unipolar LVZ had an area under the curve of 0.82 (95% CI, 0.69-0.95; P < .001), and percentage area of unipolar LVZ had an area under the curve of 0.83 (95% CI, 0.71-0.96; P = .01). Cutoff of >3 segments for extent of unipolar LVZ had the best diagnostic accuracy (sensitivity, 90%; specificity, 67%) and cutoff of 33% for percentage area of unipolar LVZ had the best diagnostic accuracy (sensitivity, 95%; specificity, 60%) for VT.

CONCLUSION

In NICM, extent and percentage area of unipolar LVZs are significant predictors of VT. Cutoffs of >3 segments of unipolar LVZ and >33% area of unipolar LVZ have good diagnostic accuracies for association with VT.

Blood Pressure Lowering in Patients With Central Hypertension: A randomized Clinical Trial

BACKGROUND

Cuff blood pressure (BP) is recommended for guiding hypertension management. However, central BP has been proposed as a superior clinical measurement. This study aimed to determine whether controlling hypertension as measured by central BP was beneficial in reducing left ventricular mass index beyond control of standard cuff hypertension.

METHODS

This multicenter, open-label, blinded-end point trial was conducted in individuals treated for uncomplicated hypertension with controlled cuff BP (<140/90 mm Hg) but elevated central BP (≥0.5 SD above age- and sex-specific normal values). Participants were randomized to 24-months intervention with spironolactone 25 mg/day (n=148) or usual care control (n=153). The primary outcome was change in left ventricular mass index measured by cardiac MRI. Cuff and central BPs were measured by clinic, 7-day home and 24-hour ambulatory BPs.

RESULTS

At 24-months, there was a greater reduction in left ventricular mass index (-3.2 [95% CI, -5.0 to -1.3] g/m2; P=0.001) with intervention compared with control. Cuff and central BPs were lowered by a similar magnitude across all BP measurement modes (eg, clinic cuff systolic BP, -6.16 [-9.60 to -2.72] mm Hg and clinic central systolic BP, -4.96 [-8.06 to -1.86] mm Hg; P≥0.48 all). Secondary analyses found that changes in left ventricular mass index correlated to changes in BP, with the magnitude of effect nearly identical for BP measured by cuff (eg, 24-hour systolic BP, β, 0.17 [0.02-0.31] g/m2) or centrally (24-hour systolic BP, β, 0.16 [0.01-0.32] g/m2).

CONCLUSIONS

Among individuals with central hypertension, spironolactone had beneficial effects in reducing LV mass. Secondary analyses showed that changes in LV mass were equally well associated with lower measured standard cuff BP and central BP.

REGISTRATION

URL: https://www.anzctr.org.au/; Unique identifier: ACTRN12613000053729.

Association between long-term use of calcium channel blockers (CCB) and the risk of breast cancer: a retrospective longitudinal observational study protocol

INTRODUCTION

Calcium channel blockers (CCB), a commonly prescribed antihypertensive (AHT) medicine, may be associated with increased risk of breast cancer. The proposed study aims to examine whether long-term CCB use is associated with the development of breast cancer and to characterise the dose-response nature of any identified association, to inform future hypertension management.

METHODS AND ANALYSIS

The study will use data from 2 of Australia's largest cohort studies; the Australian Longitudinal Study on Women's Health, and the 45 and Up Study, combined with the Rotterdam Study. Eligible women will be those with diagnosed hypertension, no history of breast cancer and no prior CCB use at start of follow-up (2004-2009). Cumulative dose-duration exposure to CCB and other AHT medicines will be captured at the earliest date of: the outcome (a diagnosis of invasive breast cancer); a competing risk event (eg, bilateral mastectomy without a diagnosis of breast cancer, death prior to any diagnosis of breast cancer) or end of follow-up (censoring event). Fine and Gray competing risks regression will be used to assess the association between CCB use and development of breast cancer using a generalised propensity score to adjust for baseline covariates. Time-varying covariates related to interaction with health services will also be included in the model. Data will be harmonised across cohorts to achieve identical protocols and a two-step random effects individual patient-level meta-analysis will be used.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the following Human research Ethics Committees: Curtin University (ref No. HRE2022-0335), NSW Population and Health Services Research Ethics Committee (2022/ETH01392/2022.31), ACT Research Ethics and Governance Office approval under National Mutual Acceptance for multijurisdictional data linkage research (2022.STE.00208). Results of the proposed study will be published in high-impact journals and presented at key scientific meetings.

TRIAL REGISTRATION NUMBER

NCT05972785.

Diagnostic accuracy of self-reported age-related macular degeneration in the ASPREE Longitudinal Study of Older Persons

BACKGROUND

The validity of findings from epidemiological studies using self-report of ophthalmic conditions depends on several factors. We assessed the diagnostic accuracy of self-reported age-related macular degeneration (AMD) among older Australians enroled in a primary prevention clinical trial and compared diagnostic accuracy between demographic subgroups.

METHODS

At baseline (2010-2015), Australian sub-study participants of the ASPirin in Reducing Events in the Elderly (ASPREE) trial, underwent bilateral two-field, 45° non-mydriatic colour retinal photography. Beckman classification of any-stage AMD was used as the reference standard diagnosis. Participants were asked whether a doctor had ever diagnosed them with "macular degeneration" (the index test) via a paper-based questionnaire as part of the ASPREE Longitudinal Study of Older Persons (ALSOP) within the first year of enrolment.

RESULTS

In total, 4193 participants were included (aged 70-92 years, 50.8% female). Of those, 262 (6.3%) reported having AMD and 92 (2.2%) were unsure. Retinal grading detected 2592 (61.8%) with no AMD, 867 (20.7%) with early, 686 (16.4%) with intermediate and 48 (1.1%) with late AMD (n = 1601 with any-stage AMD, 38.2%). Self-reported AMD had 11.4% sensitivity (95% CI 9.9-13.1) and 96.9% specificity (95% CI 96.2-97.6) for any-stage AMD, with 69.8% and 63.9% positive and negative predictive values. Sensitivity was higher among participants with late-stage AMD (87.5%), older participants (26.8%), and those with poorer vision (41.0%).

CONCLUSIONS

Although most participants with late-stage AMD were aware of having AMD, the majority with early and intermediate AMD were not. Therefore, findings from studies that rely on disease self-report should be interpreted with caution.

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.

Efficacy of left bundle branch area pacing versus biventricular pacing in patients treated with cardiac resynchronization therapy: Select site - cohort study

BACKGROUND

Cardiac resynchronization therapy (CRT) is typically attempted with biventricular (BiV) pacing. One-third of patients are nonresponders. Left bundle branch area pacing (LBBAP) has been evaluated as an alternative means.

OBJECTIVE

The purpose of this study was to assess the feasibility and clinical response of permanent LBBAP as an alternative to BiV pacing.

METHODS

Of 479 consecutive patients referred with heart failure, 50 with BiV-CRT and 51 with LBBAP-CRT were included in this analysis after study exclusions. Quality-of-Life (QoL) assessments, echocardiographic measurements, and New York Heart Association (NYHA) class were obtained at baseline and at 6-monthly intervals.

RESULTS

There were no differences in baseline characteristics between groups (all P > .05). Clinical outcomes such as left ventricular ejection fraction, left ventricular end-systolic volume, QoL, and NYHA class were significantly improved for both pacing groups compared to baseline. The LBBAP-CRT group showed greater improvement in left ventricular ejection fraction at 6 months (P = .001) and 12 months (P = .021), accompanied by greater reduction in left ventricular end-systolic volume (P = .007). QRS duration < 120 ms (baseline 160.82 ± 21.35 ms vs 161.08 ± 24.48 ms) was achieved in 30% in the BiV-CRT group vs 71% in the LBBAP-CRT group (P ≤ .001). Improvement in NYHA class (P = .031) and QoL index was greater (P = .014). Reduced heart failure admissions (P = .003) and health care utilization (P < .05) and improved lead performance (P < .001) were observed in the LBBAP-CRT group.

CONCLUSION

LBBAP-CRT is feasible and effective CRT. It results into a meaningful improvement in QoL and reduction in health care utilization. This can be offered as an alternative to BiV-CRT or potentially as first-line therapy.

Characteristics of the phenotype of mixed cardiomyopathy in patients with implantable cardioverter-defibrillators

BACKGROUND OR PURPOSE

The prognosis of m ixed cardiomyopathy (CMP) in patients with implanted cardioverter-defibrillators (ICDs) has not been investigated. We aim to study the demographic, clinical, device therapies and survival characteristics of mixed CMP in a cohort of patients implanted with a defibrillator.

METHODS

The term mixed CMP was used to categorise patients with impaired left ventricular ejection fraction attributed to documented non-ischemic triggers with concomitant moderate coronary artery disease. This is a single center observational cohort of 526 patients with a mean follow-up of 8.7 ± 3.5 years.

RESULTS

There were 42.5% patients with ischemic cardiomyopathy (ICM), 26.9% with non-ischemic cardiomyopathy (NICM) and 30.6% with mixed CMP. Mixed CMP, compared to NICM, was associated with higher mean age (69.1 ± 9.6 years), atrial fibrillation (55.3%) and greater incidence of comorbidities. The proportion of patients with mixed CMP receiving device shocks was 23.6%, compared to 18.4% in NICM and 27% in ICM. The VT cycle length recorded in mixed CMP (281.6 ± 43.1 ms) was comparable with ICM (282.5 ± 44 ms; p = 0.9) and lesser than NICM (297.7 ± 48.7 ms; p = 0.1). All-cause mortality in mixed CMP (21.1%) was similar to ICM (20.1%; p = 0.8) and higher than NICM (15.6%; p = 0.2). The Kaplan-Meier curves revealed hazards of 1.57 (95% CI: 0.91, 2.68) for mixed CMP compared to NICM.

CONCLUSION

In a cohort of patients with ICD, the group with mixed CMP represents a phenotype predominantly comprised of the elderly with a higher incidence of comorbidities. Mixed CMP resembles ICM in terms of number of device shocks and VT cycle length. Trends of long-term prognosis of patients with mixed CMP are worse than NICM and similar to ICM.

Correlation of myocardial strain by CMR-feature tracking with substrate abnormalities detected by electro-anatomical mapping in patients with nonischemic cardiomyopathy

BACKGROUND

Late gadolinium enhancement (LGE) detected by cardiac MRI (CMR) has low correlation with low voltage zones (LVZs) detected by electroanatomical mapping (EAM). We aim to study correlation of myocardial strain by CMR- Feature Tracking (FT) alongside LGE with LVZs detected by EAM.

METHODS

Nineteen consecutive CMRs of patients with EAM were analyzed offline by CMR-FT. Peak value of circumferential strain (CS), longitudinal strain (LS), and LGE was measured in each segment of the left ventricle (17-segment model). The percentage of myocardial segments with CS and LS > -17% was determined. Percentage area of LGE-scar was calculated. Global and segment-wise bipolar and unipolar voltage was collected. Percentage area of bipolar LVZ (<1.5 mV) and unipolar LVZ (<8.3 mV) was calculated.

RESULTS

Mean age was 62±11 years. Mean LVEF was 37±13%. Mean global CS was -11.8±5%. Mean global LS was -11.2±4%. LGE-scar was noted in 74% of the patients. Mean percentage area of LGE-scar was 5%. There was significant correlation between percentage abnormality detected by LS with percentage bipolar LVZ (r = +0.5, p = 0.03) and combined percentage CS+LS abnormality with percentage unipolar LVZ (r = +0.5, p = 0.02). Per-unit increase in CS increased the percentage area of unipolar LVZ by 2.09 (p = 0.07) and per-unit increase in LS increased the percentage area of unipolar LVZ by 2.49 (p = 0.06). The concordance rates between CS and LS to localize segments with bipolar/unipolar LVZ were 79% and 95% compared to 63% with LGE.

CONCLUSIONS

Myocardial strain detected by CMR-FT has a better correlation with electrical low voltage zones than the conventional LGE.

Semaglutide in Patients With Obesity and Heart Failure Across Mildly Reduced or Preserved Ejection Fraction

BACKGROUND

Many therapies for heart failure (HF) have shown differential impact across the spectrum of left ventricular ejection fraction (LVEF).

OBJECTIVES

In this prespecified analysis, the authors assessed the effects of semaglutide across the baseline LVEF strata in patients with the obesity phenotype of HF with preserved ejection fraction (HFpEF) in the STEP-HFpEF (Semaglutide Treatment Effect in People with obesity and HFpEF) trial.

METHODS

STEP-HFpEF randomized 529 patients (263 semaglutide; 266 placebo). For this prespecified analysis, patients were categorized into 3 groups based on LVEF: 45% to 49% (n = 85), 50% to 59% (n = 215), and ≥60% (n = 229).

RESULTS

At 52 weeks, semaglutide improved the dual primary endpoints of Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (estimated treatment difference: EF [ejection fraction] 45%-49%: 5.0 points [95% CI: -2.7 to 12.8 points], EF 50%-59%: 9.8 points [95% CI: 5.0 to 14.6 points], and EF ≥60%: 7.4 points [95% CI: 2.8 to 12.0 points]; P interaction = 0.56) and body weight (EF: 45%-49%: -7.6 [95% CI: -10.7 to -4.4], EF 50%-59%: -10.6 [95% CI: -12.6 to -8.6] and EF ≥60%: -11.9 [95% CI: -13.8 to -9.9]; P interaction = 0.08), to a similar extent across LVEF categories. Likewise, LVEF did not influence the benefit of semaglutide on confirmatory secondary endpoints: 6-minute walk distance (P interaction = 0.19), hierarchal composite endpoint (P interaction = 0.43), and high-sensitivity C-reactive protein (P interaction = 0.26); or exploratory endpoint of N-terminal pro-brain natriuretic peptide (P interaction = 0.96). Semaglutide was well-tolerated across LVEF categories.

CONCLUSIONS

In patients with HFpEF and obesity, semaglutide 2.4 mg improved symptoms, physical limitations, and exercise function, and reduced inflammation and body weight to a similar extent across LVEF categories. These data support treatment with semaglutide in patients with the obesity phenotype of HFpEF regardless of LVEF. (Research Study to Investigate How Well Semaglutide Works in People Living With Heart Failure and Obesity [STEP-HFpEF]; NCT04788511).

Persistence of Detectable Anti-Pneumococcal Antibodies 4 Years After Pneumococcal Polysaccharide Vaccination in a Randomised Controlled Trial: The Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE)

AIM

Mouse models have indicated that the pneumococcal polysaccharide vaccine (PPV) can reduce atherosclerosis. This is probably through a process of molecular mimicry, where phosphorylcholine in the capsular polysaccharide of the vaccine elicits antibodies that cross-react with oxidised low-density lipoprotein and reduce plaque. We investigated whether a similar mechanism occurs in humans.

METHODS

A large national blinded, randomised, placebo-controlled trial of the PPV (Australian Study for the Prevention through Immunisation of Cardiovascular Events [AUSPICE]) is underway with fatal and nonfatal cardiovascular disease (CVD) events as the primary outcome. Participants at one centre agreed to a substudy measuring a number of biomarkers and surrogates of CVD over 4 years, including anti-pneumococcal antibodies (immunoglobulin G and immunoglobulin M), C-reactive protein, carotid intima-media thickness, pulse wave velocity, insulin, fasting blood glucose, glycated haemoglobin, and hepatorenal index.

RESULTS

Antipneumococcal immunoglobulin G and immunoglobulin M were both present and statistically significantly increased in the treated group compared to control at 4 years. However, there were no differences in any of the surrogate measures of CVD or metabolic markers at 4 years.

CONCLUSIONS

While there were prolonged differences in anti-pneumococcal antibody titres following PPV vaccination, these did not appear to provide any cardioprotective effect, as measured by a range of markers. Final results using the fatal and nonfatal CVD events await the completion of national health record linkage next year.

TRIAL REGISTRATION

ACTRN12615000536561.

Long-term mortality in heart failure with mid-range ejection fraction: systematic review and meta-analysis

AIMS

Heart failure patients with mid-range ejection fraction (HFmrEF) have overlapping clinical features, compared with patients with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). We aim to perform a meta-analysis of studies reporting long-term outcomes in HFmrEF compared with HFrEF and HFpEF.

METHODS AND RESULTS

Data from 18 eligible large-scale studies including 126 239 patients were pooled. Patients with HFmrEF had a lower risk of all-cause death than those with HFrEF [risk ratio (RR) = 0.92; 95% CI = 0.85-0.98; P < 0.001]. This significant difference was seen in the follow-up at 1, 2, and 3 years. Patients with HFmrEF had significantly lower risk of cardiovascular (CV) deaths than HFrEF (RR = 0.77; 95% CI = 0.65-0.92; P < 0.001). Subgroup analysis showed that studies recruiting >50% of males had higher risk of deaths with HFrEF (RR = 1.15; 95% CI = 1.04-1.26; P = 0.006). When compared with HFpEF, patients with HFmrEF had comparable risk of all-cause death (RR = 1.02; 95% CI = 0.96-1.09; P = 0.53). Similarly, there were no differences in the 1, 2, and 3 year deaths; CV and non-CV deaths were insignificant between HFmrEF and HFpEF.

CONCLUSIONS

The results of the study support that HFmrEF has better prognosis than HFrEF but similar prognosis when compared with HFpEF. Gender disparity between studies seems to influence the results between HFmrEF and HFrEF. Transition in left ventricular ejection fraction (LVEF), which could not be addressed in the study, may play a decisive role in determining outcomes. PROSPERO review registration number CRD42021277107.

Sleep-disordered breathing was associated with lower health-related quality of life and cognitive function in a cross-sectional study of older adults

Background and objective

The clinical significance of sleep‐disordered breathing (SDB) in older age is uncertain. This study determined the prevalence and associations of SDB with mood, daytime sleepiness, quality of life (QOL) and cognition in a relatively healthy older Australian cohort.

Methods

A cross‐sectional analysis was conducted from the Study of Neurocognitive Outcomes, Radiological and retinal Effects of Aspirin in Sleep Apnoea. Participants completed an unattended limited channel sleep study to measure the oxygen desaturation index (ODI) to define mild (ODI 5–15) and moderate/severe (ODI ≥ 15) SDB, the Centre for Epidemiological Studies Scale, the Epworth Sleepiness Scale, the 12‐item Short‐Form for QOL and neuropsychological tests.

Results

Of the 1399 participants (mean age 74.0 years), 36% (273 of 753) of men and 25% (164 of 646) of women had moderate/severe SDB. SDB was associated with lower physical health‐related QOL (mild SDB: beta coefficient [β] −2.5, 95% CI −3.6 to −1.3, p < 0.001; moderate/severe SDB: β −1.8, 95% CI −3.0 to −0.6, p = 0.005) and with lower global composite cognition (mild SDB: β −0.1, 95% CI −0.2 to 0.0, p = 0.022; moderate/severe SDB: β −0.1, 95% CI −0.2 to 0.0, p = 0.032) compared to no SDB. SDB was not associated with daytime sleepiness nor depression.

Conclusion

SDB was associated with lower physical health‐related quality of life and cognitive function. Given the high prevalence of SDB in older age, assessing QOL and cognition may better delineate subgroups requiring further management, and provide useful treatment target measures for this age group.

The clinical implications for sleep‐disordered breathing (SDB) in older age remain uncertain. This study of healthy community‐dwelling older Australians reports significant associations between SDB and a lower physical health‐related quality of life, in contrast to other studies of SDB in older age, and between SDB and lower cognitive function.

See relatededitorial

Generation of cardio-protective antibodies after pneumococcal polysaccharide vaccine: Early results from a randomised controlled trial

BACKGROUND AND AIMS

Observational studies have demonstrated that the pneumococcal polysaccharide vaccine (PPV) is associated with reduced risk of cardiovascular events. This may be mediated through IgM antibodies to OxLDL, which have previously been associated with cardioprotective effects. The Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE) is a double-blind, randomised controlled trial (RCT) of PPV in preventing ischaemic events. Participants received PPV or placebo once at baseline and are being followed-up for incident fatal and non-fatal myocardial infarction or stroke over 6 years.

METHODS

A subgroup of participants at one centre (Canberra; n = 1,001) were evaluated at 1 month and 2 years post immunisation for changes in surrogate markers of atherosclerosis, as pre-specified secondary outcomes: high-sensitive C-reactive protein (CRP), pulse wave velocity (PWV), and carotid intima-media thickness (CIMT). In addition, 100 participants were randomly selected in each of the intervention and control groups for measurement of anti-pneumococcal antibodies (IgG, IgG2, IgM) as well as anti-OxLDL antibodies (IgG and IgM to CuOxLDL, MDA-LDL, and PC-KLH).

RESULTS

Concentrations of anti-pneumococcal IgG and IgG2 increased and remained high at 2 years in the PPV group compared to the placebo group, while IgM increased and then declined, but remained detectable, at 2 years. There were statistically significant increases in all anti-OxLDL IgM antibodies at 1 month, which were no longer detectable at 2 years; there was no increase in anti-OxLDL IgG antibodies. There were no significant changes in CRP, PWV or CIMT between the treatment groups at the 2-year follow-up.

CONCLUSIONS

PPV engenders a long-lasting increase in anti-pneumococcal IgG, and to a lesser extent, IgM titres, as well as a transient increase in anti-OxLDL IgM antibodies. However, there were no detectable changes in surrogate markers of atherosclerosis at the 2-year follow-up. Long-term, prospective follow-up of clinical outcomes is continuing to assess if PPV reduces CVD events.

Computerized tomography image correlation of His bundle/deep septal pacing location and outcomes: an analysis from the Canberra HIs bundle/deep septal Pacing Study (CHIPS)

Background

Localisation of the conduction system under fluoroscopy is not easy and the ideal location of the pacing leads in physiological pacing is still being debated.

Objective

The primary aim was to assess the lead locations using cardiac CT scan. Secondary aims were clinical outcomes including success and safety of the procedure and lead performance.

Methods

Of the 100 consecutive patients who received physiological pacing, 34 patients underwent follow-up cardiac CT scan. The four different types of pacing were identified as His bundle (HBP), para-Hisian, left bundle branch (LBBP), and deep septal pacing.

Results

Most patients had successful HBP via the right atrium (RA) (87.5%) as compared to the right ventricle (RV) (12.5%). Lower thresholds were observed when leads were placed within 2 mm of the junction of the membranous and muscular ventricular septum. Unlike HBP, LBBP was possible at a wide region of the septum and selective capture of individual fascicles was feasible. LBBP showed deeper penetration of leads into the septum, as compared to deep septal pacing (70% vs. 45%). Approximately, 80% of patients did not have an intra-ventricular portion of the membranous septum.

Conclusions

The anterior part of the atrio-ventricular (AV) septum at the junction between the membranous and muscular septum via RA appeared to be the best target to successfully pace His bundle. LBBP was possible at a wide region of the septum and selective capture of individual fascicle was feasible. Adequate depth of penetration of lead was very important to capture the left bundle.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10840-022-01133-z.

Optimal Blood Pressure Keeps Our Brains Younger

Background: Elevated blood pressure (BP) is a major health risk factor and the leading global cause of premature death. Hypertension is also a risk factor for cognitive decline and dementia. However, when elevated blood pressure starts impacting cerebral health is less clear. We addressed this gap by estimating how a validated measure of brain health relates to changes in BP over a period of 12 years. Methods: Middle-age (44-46 years at baseline, n = 335, 52% female) and older-age (60-64 years, n = 351, 46% female) cognitively intact individuals underwent up to four brain scans. Brain health was assessed using a machine learning approach to produce an estimate of "observed" age (BrainAGE), which can be contrasted with chronological age. Longitudinal associations between blood pressures and BrainAGE were assessed with linear mixed-effects models. Results: A progressive increase in BP was observed over the follow up (MAP = 0.8 mmHg/year, SD = 0.92; SBP = 1.41 mmHg/year, SD = 1.49; DBP = 0.61 mmHg/year, SD = 0.78). In fully adjusted models, every additional 10 mmHg increase in blood pressure (above 90 for mean, 114 for systolic, and 74 for diastolic blood pressure) was associated with a higher BrainAGE by 65.7 days for mean, and 51.1 days for systolic/diastolic blood pressure. These effects occurred across the blood pressure range and were not exclusively driven by hypertension. Conclusion: Increasing blood pressure is associated with poorer brain health. Compared to a person becoming hypertensive, somebody with an ideal BP is predicted to have a brain that appears more than 6 months younger at midlife.

Machine Learning of ECG Waveforms to Improve Selection for Testing for Asymptomatic Left Ventricular Dysfunction Prompt

OBJECTIVES

To identify whether machine learning from processing of continuous wave transforms (CWTs) to provide an "energy waveform" electrocardiogram (ewECG) could be integrated with echocardiographic assessment of subclinical systolic and diastolic left ventricular dysfunction (LVD).

BACKGROUND

Asymptomatic LVD has management implications, but routine echocardiography is not undertaken in subjects at risk of heart failure. Signal processing of the surface ECG with the use of CWT can identify abnormal myocardial relaxation.

METHODS

EwECG and echocardiography were undertaken in 398 participants at risk of heart failure (HF). Reduced global longitudinal strain (GLS ≤16%)), diastolic abnormalities (E/e' >15, left atrial enlargement with E/e' >10 or impaired relaxation) or LV hypertrophy defined LVD. EwECG feature selection and supervised machine-learning by random forest (RF) classifier was undertaken with 643 CWT-derived features and the Atherosclerosis Risk in Communities (ARIC) heart failure risk score.

RESULTS

The ARIC score and 18 CWT features were selected to build a RF predictive model for LVD in a training dataset (n = 287; 60% female, median age 71 [interquartile range: 68 to 74] years). Model performance was tested in an independent group (n = 111; 49% female, median age 61 years [59 to 66 years]), demonstrating 85% sensitivity and 72% specificity (area under the receiver-operating characteristic curve [AUC]: 0.83; 95% confidence interval [CI]: 0.74 to 0.92). With ARIC score removed, sensitivity was 88% and specificity, 70% (AUC: 0.78; 95% CI: 0.70 to 0.86). RF models for reduced GLS and diastolic abnormalities including similar features had sensitivities that were unsuitable for screening. Conventional candidates for LVD screening (ARIC score, N-terminal pro-B-type natriuretic peptide, and standard automated ECG analysis) had inferior discriminative ability. Integration of ewECG in screening of people at risk of HF would reduce need for echocardiography by 45% while missing 12% of LVD cases.

CONCLUSIONS

Machine learning applied to ewECG is a sensitive screening test for LVD, and its integration into screening of patients at risk for HF would reduce the number of echocardiograms by almost one-half.

Clinical and cardiac structural predictors of atrial fibrillation persistence

AIMS

The persistence of atrial fibrillation (AF) has been associated with differential clinical outcomes, with studies showing that persistent and permanent AF results in increased morbidity and mortality when compared to the paroxysmal subtype. Given the established prognostic implications of AF subtype, we sought to discern the clinical and structural cardiac parameters associated with persistent/ permanent AF.

MATERIALS AND METHODS

Consecutive patients admitted to our institution between January 2013 and January 2018 with a primary diagnosis of non-valvular AF who underwent comprehensive transthoracic echocardiography were retrospectively appraised. Assessment of clinical and echocardiographic parameters was undertaken and compared according to AF subtype.

RESULTS

Of 1010 patients, 665 (mean age 66.8 ± 13.5 years, 53% men) had comprehensive transthoracic echocardiography on index admission and were included in the primary analysis. The majority of patients (n = 468; 70%) had paroxysmal AF while 197 (30%) had persistent/ permanent AF. Multivariable logistic regression analysis showed that heart failure (adjusted OR 3.135; 95% CI 2.099 to 4.682, P < .001), right atrial (RA) area ≥18 cm² (adjusted OR 2.147; 95% CI 1.413 to 3.261, P < .001) and left atrial emptying fraction (LAEF) ≤34% (adjusted OR 2.959; 95% CI 1.991 to 4.398, P < .001) were independent predictors of persistent /permanent AF.

CONCLUSIONS

The presence of heart failure, increased RA size and impaired LA function were associated with persistent/ permanent AF. These clinical and cardiac structural risk markers of AF persistence may identify a target population for early intervention to prevent adverse cardiovascular outcomes.

Cardiac resynchronization with His-CRT-D in a patient with severe heart failure and Scimitar syndrome

Cardiac resynchronization therapy with His-bundle pacing is evolving rapidly as a viable cardiac device strategy for the treatment of severe chronic heart failure. The success of this technique in patients with congenital heart disease is facilitated by advanced integrated imaging modalities. We report a case of cardiac resynchronization therapy with His-bundle pacing with defibrillator for the management of a patient with heart failure with severely reduced ejection fraction, left bundle branch block, and congenital heart disease characterized by Scimitar syndrome with cardiac dextroposition. We highlight the contribution of integrated imaging modalities to guide accurate lead positioning.

Choice of Statistical Tools for Outlier Removal Causes Substantial Changes in Analyte Reference Intervals in Healthy Populations

BACKGROUND

Reference intervals are an important aid in medical practice as they provide clinicians a guide as to whether a patient is healthy or diseased.Outlier results in population studies are removed by any of a variety of statistical measures. We have compared several methods of outlier removal and applied them to a large body of analytes from a large population of healthy persons.

METHODS

We used the outlier exclusion criteria of Reed-Dixon and Tukey and calculated reference intervals using nonparametric and Harrell-Davis statistical methods and applied them to a total of 36 different analytes.

RESULTS

Nine of 36 analytes had a greater than 20% difference in the upper reference limit, and for some the difference was 100% or more.

CONCLUSIONS

For some analytes, great importance is attached to the reference interval. We have shown that different statistical methods for outlier removal can cause large changes to reported reference intervals. So that population studies can be readily compared, common statistical methods should be used for outlier removal.

Longitudinal trajectories of hippocampal volume in middle to older age community dwelling individuals

Understanding heterogeneity in brain aging trajectories is important to estimate the extent to which aging outcomes can be optimized. Although brain changes in late life are well-characterized, brain changes in middle age are not well understood. In this study, we investigated hippocampal change in a generally healthy community-living population of middle (n = 421, mean age 47.2 years) and older age (n = 411, mean age 63.0 years) individuals, over a follow-up of up to 12 years. Manually traced hippocampal volumes were analyzed using multilevel models and latent class analysis to investigate longitudinal aging trajectories and laterality and sex effects, and to identify subgroups that follow different aging trajectories. Hippocampal volumes decreased on average by 0.18%/year in middle age and 0.3%/year in older age. Men tended to experience steeper declines than women in middle age only. Three subgroups of individuals following different trajectories were identified in middle age and 2 in older age. Contrary to expectations, the subgroup containing two-thirds of older age participants maintained stable hippocampal volumes across the follow-up.

Baseline characteristics and age-related macular degeneration in participants of the "ASPirin in Reducing Events in the Elderly" (ASPREE)-AMD trial

PURPOSE

To describe the baseline participant characteristics in the ASPREE-AMD study, investigating the effect of aspirin on AMD incidence and progression.

METHODS

Australian participants from the ASPirin in Reducing Events in the Elderly (ASPREE) trial, randomized to 100 mg aspirin daily or placebo, had non-mydriatic, digital color fundus images graded according to the Beckman AMD classification. Associations with AMD were determined for baseline characteristics and genetic risk variants.

RESULTS

ASPREE-AMD sub-study enrolled 4993 participants with gradable macular images. Median age was 73.4 years (IQR, 71.5, 76.6), 52% were female, 10% had diabetes mellitus, 73% had hypertension, and 44% were former/current smokers. Early, intermediate and late AMD (detected in 20.6%, 16.1%, 1.1%, respectively), significantly associated with age, were also associated with increasing HDL levels: OR = 1.52 (95%CI, 1.26, 1.84), OR = 1.43 (1.17, 1.77) and OR = 1.96 (1.02, 3.76), respectively. Female sex was associated with early [OR = 1.37 (1.16, 1.62)], and intermediate [OR = 1.35 (1.12, 1.63)] AMD, as was previous regular use of aspirin, with OR = 1.46 (1.11, 1.92) and OR = 1.37 (1.01, 1.85), respectively. Current smoking had increased odds for late AMD, OR = 4.02 (1.42, 11.36). Genetic risk variant rs3750846 (ARMS2/HTRA1) was associated with each AMD stage (p < 0.001), risk variants rs570618 and rs10922109 (CFH) with intermediate and late AMD (p < 0.001), and rare variant rs147859257 (C3) with late AMD (p < 0.001). The randomized groups were well balanced for all analyzed AMD risk factors.

CONCLUSIONS

Observed associations are typical of AMD. The ASPREE-AMD clinical trial provides a unique opportunity to determine the risks and benefits of low-dose aspirin for AMD incidence and progression in elderly population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trial Registry: ACTRN 12613000755730.

Subgroup analysis of the ASPirin in Reducing Events in the Elderly randomized clinical trial suggests aspirin did not improve outcomes in older adults with chronic kidney disease

The role of aspirin for primary prevention in older adults with chronic kidney disease (CKD) is unclear. Therefore, post hoc analysis of the randomized controlled trial ASPirin in Reducing Events in the Elderly (ASPREE) was undertaken comparing 100 mg of enteric-coated aspirin daily against matching placebo. Participants were community dwelling adults aged 70 years and older in Australia, 65 years and older in the United States, all free of a history of dementia or cardiovascular disease and of any disease expected to lead to death within five years. CKD was defined as present at baseline if either eGFR under 60mL/min/1.73m² or urine albumin to creatinine ratio 3 mg/mmol or more. In 4758 participants with and 13004 without CKD, the rates of a composite endpoint (dementia, persistent physical disability or death), major adverse cardiovascular events and clinically significant bleeding in the CKD participants were almost double those without CKD. Aspirin's effects as estimated by hazard ratios were generally similar between CKD and non-CKD groups for dementia, persistent physical disability or death, major adverse cardiovascular events and clinically significant bleeding. Thus, in our analysis aspirin did not improve outcomes in older people while increasing the risk of bleeding, with mostly consistent effects in participants with and without CKD.

Factors Associated With Treatment and Control of Hypertension in a Healthy Elderly Population Free of Cardiovascular Disease: A Cross-sectional Study

BACKGROUND

Despite readily available treatments, control of blood pressure (BP) with population aging remains suboptimal. Further, there are gaps in the understanding of the management of high BP in the aged. We explored antihypertensive treatment and control among elderly hypertensive participants free from overt cardiovascular disease (CVD), and identified factors related to both "untreated" and "treated but uncontrolled" high BP.

METHODS

We analyzed baseline data from 19,114 individuals aged ≥65 years enrolled from Australia and United States (US) in the ASPirin in Reducing Events in the Elderly study. Hypertension was defined as an average systolic/diastolic BP ≥140/90 mm Hg and/or the use of any BP lowering medication. "Controlled hypertension" was defined if participants were receiving antihypertensive medication and BP <140 and 90 mm Hg. Descriptive analyses were used to summarize hypertension control rates; logistic regression was used to investigate relationships with treatment and BP control.

RESULTS

Overall, 74% (14,213/19,114) of participants were hypertensive; and of these 29% (4,151/14,213) were untreated. Among those treated participants, 53% (5,330/10,062) had BP ≥140/90 mm Hg. Participants who were untreated were more likely to be men, have higher educational status, and be in good physical health, and less likely to have significant comorbidities. The factors related to "treated but uncontrolled" BP included older age, male, Black race (vs. White), using antihypertensive monotherapy (vs. multiple) and residing in Australia (vs. US).

CONCLUSIONS

High levels of "untreated" and "treated but uncontrolled" BP occur in healthy elderly people without CVD, suggesting there are opportunities for better BP control in the primary prevention of CVD in this population.

CLINICAL TRIALS REGISTRATION

NCT01038583.

PREVEntion and regReSsive Effect of weight-loss and risk factor modification on Atrial Fibrillation: the REVERSE-AF study

Aims

Atrial fibrillation (AF) is a progressive disease. Obesity is associated with progression of AF. This study evaluates the impact of weight and risk factor management (RFM) on progression of the AF.

Methods and results

As described in the Long-Term Effect of Goal-Directed Weight Management in an Atrial Fibrillation Cohort: A Long-Term Follow-Up (LEGACY) Study, of 1415 consecutive AF patients, 825 had body mass index ≥ 27 kg/m2 and were offered weight and RFM. After exclusion, 355 were included for analysis. Weight loss was categorized as: Group 1 (<3%), Group 2 (3-9%), and Group 3 (≥10%). Change in AF type was determined by clinical review and 7-day Holter yearly. Atrial fibrillation type was categorized as per the Heart Rhythm Society consensus. There were no differences in baseline characteristic or follow-up duration between groups (P = NS). In Group 1, 41% progressed from paroxysmal to persistent and 26% from persistent to paroxysmal or no AF. In Group 2, 32% progressed from paroxysmal to persistent and 49% reversed from persistent to paroxysmal or no AF. In Group 3, 3% progressed to persistent and 88% reversed from persistent to paroxysmal or no AF (P < 0.001). Increased weight loss was significantly associated with greater AF freedom: 45 (39%) in Group 1, 69 (67%) in Group 2, and 116 (86%) in Group 3 (P ≤ 0.001).

Conclusion

Obesity is associated with progression of the AF disease. This study demonstrates the dynamic relationship between weight/risk factors and AF. Weight-loss management and RFM reverses the type and natural progression of AF.

Tropheryma Whipplei Endocarditis: Case Report and Literature Review

We describe a young man who initially presented with stroke and febrile illness. He was eventually diagnosed with Tropheryma whipplei endocarditis. This is a very rare condition and to the best of our knowledge, this is the first documented case of T. whipplei endocarditis in Australia and New Zealand regions. This report aims to increase awareness of clinicians of this very rare but potentially treatable condition. It is reasonable to exclude T. whipplei endocarditis when dealing with high-risk patients who are suspected for “culture-negative” endocarditis.

Evaluating recruitment strategies for AUSPICE, a large Australian community-based randomised controlled trial

OBJECTIVES

To examine the effectiveness of different strategies for recruiting participants for a large Australian randomised controlled trial (RCT), the Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE).

DESIGN, SETTING, PARTICIPANTS

Men and women aged 55-60 years with at least two cardiovascular risk factors (hypertension, hypercholesterolaemia, overweight/obesity) were recruited for a multicentre placebo-controlled RCT assessing the effectiveness of 23-valent pneumococcal polysaccharide vaccine (23vPPV) for preventing cardiovascular events.

METHODS

Invitations were mailed by the Australian Department of Human Services to people in the Medicare database aged 55-60 years; reminders were sent 2 weeks later. Invitees could respond in hard copy or electronically. Direct recruitment was supplemented by asking invitees to extend the invitation to friends and family (snowball sampling) and by Facebook advertising.

MAIN OUTCOME

Proportions of invitees completing screening questionnaire and recruited for participation in the RCT.

RESULTS

21 526 of 154 992 invited people (14%) responded by completing the screening questionnaire, of whom 4725 people were eligible and recruited for the study. Despite the minimal study burden (one questionnaire, one clinic visit), the overall participation rate was 3%, or an estimated 10% of eligible persons. Only 16% of eventual participants had responded within 2 weeks of the initial invitation letter (early responders); early and late responders did not differ in their demographic or medical characteristics. Socio-economic disadvantage did not markedly influence response rates. Facebook advertising and snowball sampling did not increase recruitment.

CONCLUSIONS

Trial participation rates are low, and multiple concurrent methods are needed to maximise recruitment. Social media strategies may not be successful in older age groups.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12615000536561.

Recruiting general practice patients for large clinical trials: lessons from the Aspirin in Reducing Events in the Elderly (ASPREE) study

OBJECTIVE

To assess the factors that contributed to the successful completion of recruitment for the largest clinical trial ever conducted in Australia, the Aspirin in Reducing Events in the Elderly (ASPREE) study.

DESIGN

Enrolment of GPs; identification of potential participants in general practice databases; screening of participants.

SETTING, PARTICIPANTS

Selected general practices across southeast Australia (Tasmania, Victoria, Australian Capital Territory, New South Wales, South Australia).

MAJOR OUTCOMES

Numbers of patients per GP screened and randomised to participation; geographic and demographic factors that influenced screening and randomising of patients.

RESULTS

2717 of 5833 GPs approached (47%) enrolled to recruit patients for the study; 2053 (76%) recruited at least one randomised participant. The highest randomised participant rate per GP was for Tasmania (median, 5; IQR, 1-11), driven by the high rate of participant inclusion at phone screening. GPs in inner regional (adjusted odds ratio [aOR], 1.45; 95% CI, 1.14-1.84) and outer regional areas (aOR, 1.86; 95% CI, 1.19-2.88) were more likely than GPs in major cities to recruit at least one randomised participant. GPs in areas with a high proportion of people aged 70 years or more were more likely to randomise at least one participant (per percentage point increase: aOR, 1.10; 95% CI, 1.05-1.15). The number of randomised patients declined with time from GP enrolment to first randomisation.

CONCLUSION

General practice can be a rich environment for research when barriers to recruitment are overcome. Including regional GPs and focusing efforts in areas with the highest proportions of potentially eligible participants improves recruitment. The success of ASPREE attests to the clinical importance of its research question for Australian GPs.

Effect of Aspirin on All-Cause Mortality in the Healthy Elderly

BACKGROUND

In the primary analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial, now published in the Journal, we report that the daily use of aspirin did not provide a benefit with regard to the primary end point of disability-free survival among older adults. A numerically higher rate of the secondary end point of death from any cause was observed with aspirin than with placebo.

METHODS

From 2010 through 2014, we enrolled community-dwelling persons in Australia and the United States who were 70 years of age or older (or ≥65 years of age among blacks and Hispanics in the United States) and did not have cardiovascular disease, dementia, or disability. Participants were randomly assigned to receive 100 mg of enteric-coated aspirin or placebo. Deaths were classified according to the underlying cause by adjudicators who were unaware of trial-group assignments. Hazard ratios were calculated to compare mortality between the aspirin group and the placebo group, and post hoc exploratory analyses of specific causes of death were performed.

RESULTS

Of the 19,114 persons who were enrolled, 9525 were assigned to receive aspirin and 9589 to receive placebo. A total of 1052 deaths occurred during a median of 4.7 years of follow-up. The risk of death from any cause was 12.7 events per 1000 person-years in the aspirin group and 11.1 events per 1000 person-years in the placebo group (hazard ratio, 1.14; 95% confidence interval [CI], 1.01 to 1.29). Cancer was the major contributor to the higher mortality in the aspirin group, accounting for 1.6 excess deaths per 1000 person-years. Cancer-related death occurred in 3.1% of the participants in the aspirin group and in 2.3% of those in the placebo group (hazard ratio, 1.31; 95% CI, 1.10 to 1.56).

CONCLUSIONS

Higher all-cause mortality was observed among apparently healthy older adults who received daily aspirin than among those who received placebo and was attributed primarily to cancer-related death. In the context of previous studies, this result was unexpected and should be interpreted with caution. (Funded by the National Institute on Aging and others; ASPREE ClinicalTrials.gov number, NCT01038583 .).

Effect of Aspirin on Cardiovascular Events and Bleeding in the Healthy Elderly

BACKGROUND

Aspirin is a well-established therapy for the secondary prevention of cardiovascular events. However, its role in the primary prevention of cardiovascular disease is unclear, especially in older persons, who have an increased risk.

METHODS

From 2010 through 2014, we enrolled community-dwelling men and women in Australia and the United States who were 70 years of age or older (or ≥65 years of age among blacks and Hispanics in the United States) and did not have cardiovascular disease, dementia, or disability. Participants were randomly assigned to receive 100 mg of enteric-coated aspirin or placebo. The primary end point was a composite of death, dementia, or persistent physical disability; results for this end point are reported in another article in the Journal. Secondary end points included major hemorrhage and cardiovascular disease (defined as fatal coronary heart disease, nonfatal myocardial infarction, fatal or nonfatal stroke, or hospitalization for heart failure).

RESULTS

Of the 19,114 persons who were enrolled in the trial, 9525 were assigned to receive aspirin and 9589 to receive placebo. After a median of 4.7 years of follow-up, the rate of cardiovascular disease was 10.7 events per 1000 person-years in the aspirin group and 11.3 events per 1000 person-years in the placebo group (hazard ratio, 0.95; 95% confidence interval [CI], 0.83 to 1.08). The rate of major hemorrhage was 8.6 events per 1000 person-years and 6.2 events per 1000 person-years, respectively (hazard ratio, 1.38; 95% CI, 1.18 to 1.62; P<0.001).

CONCLUSIONS

The use of low-dose aspirin as a primary prevention strategy in older adults resulted in a significantly higher risk of major hemorrhage and did not result in a significantly lower risk of cardiovascular disease than placebo. (Funded by the National Institute on Aging and others; ASPREE ClinicalTrials.gov number, NCT01038583 .).

Effect of Aspirin on Disability-free Survival in the Healthy Elderly

BACKGROUND

Information on the use of aspirin to increase healthy independent life span in older persons is limited. Whether 5 years of daily low-dose aspirin therapy would extend disability-free life in healthy seniors is unclear.

METHODS

From 2010 through 2014, we enrolled community-dwelling persons in Australia and the United States who were 70 years of age or older (or ≥65 years of age among blacks and Hispanics in the United States) and did not have cardiovascular disease, dementia, or physical disability. Participants were randomly assigned to receive 100 mg per day of enteric-coated aspirin or placebo orally. The primary end point was a composite of death, dementia, or persistent physical disability. Secondary end points reported in this article included the individual components of the primary end point and major hemorrhage.

RESULTS

A total of 19,114 persons with a median age of 74 years were enrolled, of whom 9525 were randomly assigned to receive aspirin and 9589 to receive placebo. A total of 56.4% of the participants were women, 8.7% were nonwhite, and 11.0% reported previous regular aspirin use. The trial was terminated at a median of 4.7 years of follow-up after a determination was made that there would be no benefit with continued aspirin use with regard to the primary end point. The rate of the composite of death, dementia, or persistent physical disability was 21.5 events per 1000 person-years in the aspirin group and 21.2 per 1000 person-years in the placebo group (hazard ratio, 1.01; 95% confidence interval [CI], 0.92 to 1.11; P=0.79). The rate of adherence to the assigned intervention was 62.1% in the aspirin group and 64.1% in the placebo group in the final year of trial participation. Differences between the aspirin group and the placebo group were not substantial with regard to the secondary individual end points of death from any cause (12.7 events per 1000 person-years in the aspirin group and 11.1 events per 1000 person-years in the placebo group), dementia, or persistent physical disability. The rate of major hemorrhage was higher in the aspirin group than in the placebo group (3.8% vs. 2.8%; hazard ratio, 1.38; 95% CI, 1.18 to 1.62; P<0.001).

CONCLUSIONS

Aspirin use in healthy elderly persons did not prolong disability-free survival over a period of 5 years but led to a higher rate of major hemorrhage than placebo. (Funded by the National Institute on Aging and others; ASPREE ClinicalTrials.gov number, NCT01038583 .).

Increasing Body Mass Index at Midlife is Associated with Increased Cortical Thinning in Alzheimer's Disease-Vulnerable Regions

Higher body mass index (BMI) at midlife is associated with greater decreases in cognitive function at older age as well as increased Alzheimer's disease (AD) risk, compared to those with normal BMI. Here, we tested whether BMI at midlife was associated with cortical thinning in brain regions known to be affected in early AD. We examined a large sample (n = 404) of midlife individuals (44-49 years) from the PATH population-based study. Individuals were scanned with magnetic resonance imaging (1.5T) on up to three occasions over eight years. Change in cortical thickness was modeled as a linear function of BMI and change in BMI longitudinally. Being obese was associated with thinner right frontal cortex at baseline (44-49 years). Across all individuals, increasing BMI over the 8-year study period was associated with increased cortical thinning in posterior cingulate bilaterally, as well as right lingual gyrus, anterior cingulate, and the peri-calcarine sulcus. Accelerated age-related cortical atrophy at midlife, particularly in posterior cingulate, is consistent with increased risk of AD in individuals with high BMI at this age. The findings suggest that management of body weight at midlife could reduce the risk of AD.

Associations between Type 2 Diabetes Mellitus and Arterial Stiffness: A Prospective Analysis Based on the Maine-Syracuse Study

BACKGROUND

The aim of this study was to investigate prospective associations between type 2 diabetes mellitus status and the gold standard non-invasive method for ascertaining arterial stiffness, carotid femoral pulse wave velocity.

METHODS

The prospective analysis employed 508 community-dwelling participants (mean age 61 years, 60% women) from the Maine-Syracuse Longitudinal Study. Pulse wave velocity at wave 7 (2006-2010) was compared between those with type 2 diabetes mellitus at wave 6 (2001-2006) (n = 52) and non-diabetics at wave 6 (n = 456), with adjustment for demographic factors, cardiovascular risk factors and lifestyle- and pulse wave velocity-related factors.

RESULTS

Type 2 diabetes mellitus status was associated with a significantly higher pulse wave velocity (12.5 ± 0.36 vs. 10.4 ± 0.12 m/s). Multivariate adjustment for other cardiovascular risk factors and lifestyle- and pulse wave velocity-related variables did not attenuate the findings. The risk of an elevated pulse wave velocity (≥12 m/s) was over 9 times higher for those with uncontrolled type 2 diabetes mellitus than for those without diabetes (OR 9.14, 95% CI 3.23-25.9, p < 0.001).

CONCLUSIONS

Type 2 diabetes mellitus, particularly if uncontrolled, is significantly associated with risk of arterial stiffness later in life. Effective management of diabetes mellitus is an important element of protection from arterial stiffness.

Baseline Characteristics of Participants in the ASPREE (ASPirin in Reducing Events in the Elderly) Study

BACKGROUND

There are no primary prevention trials of aspirin with relevant geriatric outcomes in elderly people. ASPirin in Reducing Events in the Elderly (ASPREE) is a placebo-controlled trial of low-dose aspirin that will determine whether 5 years of daily 100-mg enteric-coated aspirin extends disability-free and dementia-free life in a healthy elderly population and whether these benefits outweigh the risks.

METHODS

Set in primary care, this randomized double-blind placebo-controlled trial has a composite primary endpoint of death, incident dementia or persistent physical disability. Participants aged 70+ years (non-minorities) or 65+ years (U.S. minorities) were free of cardiovascular disease, dementia, or physical disability and without a contraindication to, or indication for, aspirin. Baseline data include physical and lifestyle, personal and family medical history, hemoglobin, fasting glucose, creatinine, lipid panel, urinary albumin:creatinine ratio, cognition (3MS, HVLT-R, COWAT, SDMT), mood (CES-D-10), physical function (gait speed, grip strength), Katz activities of daily living and quality of life (SF-12).

RESULTS

Recruitment ended in December 2014 with 16,703 Australian and 2,411 U.S. participants, a median age of 74 (range 65-98) years and 56% women. Approximately 55% of the U.S. cohort were from minority groups; 9% of the total cohort. Proportions with hypertension, overweight, and chronic kidney disease were similar to age-matched populations from both countries although lower percentages had diabetes, dyslipidemia, and osteoarthritis.

DISCUSSION

Findings from ASPREE will be generalizable to a healthier older population in both countries and will assess whether the broad benefits of daily low-dose aspirin in prolonging independent life outweigh the risks.

Symptoms of stress and depression effect percentage of body fat and insulin resistance in healthy youth: LOOK longitudinal study

OBJECTIVE

This study examined the longitudinal and cross-sectional effects of both psychosocial stress and depressive symptoms on insulin resistance and percentage body fat in a cohort of healthy Australian children, following them from childhood into adolescence.

METHOD

Participants were 791 healthy, initially Grade 2 children (7-8 years; 394 girls), selected from the general community. Psychosocial stress was assessed using the Children's Stress Questionnaire, while depressive symptoms were assessed using the Children's Depression Inventory. Fasting blood samples for serum insulin and plasma glucose were collected to calculate the homeostasis model assessment-insulin resistance (HOMA-IR). Other measurements were height, weight, percentage body fat (dual energy x-ray absorptiometry), physical activity (pedometers), and pubertal maturation (Tanner score).

RESULTS

Boys who reported more symptoms of depression had higher insulin resistance, irrespective of adiposity (p = .016); and longitudinally, we found a trend for boys who developed more depressive symptoms to develop higher insulin resistance (p = .073). These findings did not extend to girls. Furthermore, boys and girls with higher depressive symptoms had a higher percentage of body fat (p = .011 and .020, respectively); and longitudinally, boys whose depressive symptoms increased became fatter (p = .046).

CONCLUSION

Our data provide evidence that early symptoms of depression increase insulin resistance, independent of adiposity. Our evidence that early symptoms of depression may lead to overweight, and obesity provides further reason to suggest that early attention to children with depression, even in preclinical stages, may reduce risk of chronic disease in later life. (PsycINFO Database Record

Using a thyroid disease-free population to define the reference interval for TSH and free T4 on the Abbott Architect analyser

OBJECTIVE

Thyroid disease can be subtle in its presentation, and TSH reference intervals may be artefactually increased by including persons with subclinical thyroid disease. We have therefore used a thyroid disease-free population to determine TSH and fT4 reference intervals.

DESIGN

Apparently healthy subjects were assessed by health questionnaire, drug history, clinical assessment and measurement of thyroid antibodies.

PATIENTS

Healthy subjects in a community setting.

MEASUREMENTS

TSH, free T4, antithyroglobulin and anti-TPO were measured on the Abbott Architect analyser. Subjects with clinical abnormalities, consumption of thyroid-active medications or with thyroid antibodies above the manufacturer-quoted reference intervals were excluded. TSH and fT4 data were log-transformed, and the central 95% was used to calculate reference intervals. We assessed whether these data were normally distributed. We compared samples spanning the reference intervals for both TSH and fT4 between different assays looking at biases.

RESULTS

From a population of 1,606 subjects, 140 males (18%) and 284 females (34%) were excluded. The central population 95% for TSH was 0·43-3·28 mU/l and for fT4 10·8-16·8 pmol/l. There were no age- or sex-related differences. For both analytes, the distribution was not significantly different to a Gaussian distribution (P > 0·05). For 5 commonly used assays for TSH, the maximum difference in the upper limit of the TSH reference interval was 0·48 mU/l and for fT4 the maximum difference for the upper reference limit was 4·1 pmol/l.

CONCLUSIONS

A substantial proportion of apparently healthy persons have subclinical thyroid disease. These subjects must be excluded for any thyroid hormone reference interval studies.

Comparison of Central Blood Pressure Estimated by a Cuff-Based Device With Radial Tonometry

BACKGROUND

New techniques that measure central blood pressure (BP) using an upper arm cuff-based approach require performance assessment. The aim of this study was to compare a cuff-based device (CuffCBP) to estimate central BP indices (systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP), augmentation pressure (AP), augmentation index (AIx)) with noninvasive radial tonometry (TonCBP).

METHODS

Consecutive CuffCBP (SphygmoCor Xcel) and TonCBP (SphygmoCor 8.1) duplicate recordings were measured in 182 people with treated hypertension (aged 61±7 years, 48% male). Agreement between methods was assessed using standard calibration with brachial SBP and DBP (measured with the Xcel device), as well as with brachial mean arterial pressure (MAP; 40% form factor method) and DBP.

RESULTS

The mean difference ± SD for central SBP (cSBP), central DBP (cDBP), and central PP (cPP) between methods were -0.89±3.48mm Hg (intra-class correlation (ICC) 0.977; 95% confidence interval (CI) 0.973-0.982), -0.50±1.54mm Hg (ICC 0.992, 95% CI 0.987-0.993), and -0.42±3.57mm Hg (ICC 0.966, 95% CI 0.958-0.972), indicating good agreement. Wider limits of agreement were observed for central AP (cAP) and central AIx (cAIx) (-0.91±5.31mm Hg; ICC 0.802; 95% CI 0.756-0.839, -0.99±10.91%; ICC 0.749; 95% CI 0.691-0.796). Re-calibration with brachial MAP and DBP resulted in an overestimation of cSBP with CuffCBP compared with TonCBP (8.58±19.06mm Hg, ICC 0.164, 95% CI -0.029 to 0.321).

CONCLUSION

cSBP, cDBP, and cPP derived from CuffCBP are substantially equivalent to TonCBP, although the level of agreement is dependent on calibration method. Further validity testing of CuffCBP by comparison with invasively measured central BP will be required.

Blood Pressure Variability and Prediction of Target Organ Damage in Patients With Uncomplicated Hypertension

BACKGROUND

The average of multiple blood pressure (BP) readings (mean BP) independently predicts target organ damage (TOD). Observational studies have also shown an independent relationship between BP variability (BPV) and TOD, but there is limited longitudinal data. This study aimed to determine the effects of changes in mean BP levels compared with BPV on left ventricular mass index (LVMI) and aortic pulse wave velocity (aPWV).

METHODS

Mean BP levels (research-protocol clinic BP (clinic BP), 24-hour ambulatory BP, and 7-day home BP) and BPV were assessed in 286 patients with uncomplicated hypertension (mean age 64±8 SD years, 53% women) over 12 months. Reading-to-reading BPV (from 24-hour ambulatory BP) and day-to-day BPV (from 7-day home BP) were assessed at baseline and 12 months, and visit-to-visit BPV (clinic BP) was assessed from 5 visits over 12 months. LVMI was measured by 3D echocardiography and aPWV with applanation tonometry.

RESULTS

The strongest predictors of the changes in LVMI (ΔLVMI) were the changes in mean 24-hour systolic BPs (SBPs) (P < 0.02). Similarly, the strongest predictors of the changes in aPWV (ΔaPWV) were the changes in mean 24-hour ambulatory SBPs (P < 0.01) and the changes in mean clinic SBP (P < 0.001). However, none of the changes in BPV were independently associated with ΔLVMI or ΔaPWV (P > 0.05 for all).

CONCLUSIONS

Changes in mean BP levels, but not BPV, were most relevant to changes in TOD in patients with uncomplicated hypertension. Thus, from this point of view, BPV appears to have limited clinical utility in this patient population.

Efficacy of a trivalent influenza vaccine against seasonal strains and against 2009 pandemic H1N1: A randomized, placebo-controlled trial

BACKGROUND

Before pandemic H1N1 vaccines were available, the potential benefit of existing seasonal trivalent inactivated influenza vaccines (IIV3s) against influenza due to the 2009 pandemic H1N1 influenza strain was investigated, with conflicting results. This study assessed the efficacy of seasonal IIV3s against influenza due to 2008 and 2009 seasonal influenza strains and against the 2009 pandemic H1N1 strain.

METHODS

This observer-blind, randomized, placebo-controlled study enrolled adults aged 18-64years during 2008 and 2009 in Australia and New Zealand. Participants were randomized 2:1 to receive IIV3 or placebo. The primary objective was to demonstrate the efficacy of IIV3 against laboratory-confirmed influenza. Participants reporting an influenza-like illness during the period from 14days after vaccination until 30 November of each study year were tested for influenza by real-time reverse transcription polymerase chain reaction.

RESULTS

Over a study period of 2years, 15,044 participants were enrolled (mean age±standard deviation: 35.5±14.7years; 54.4% female). Vaccine efficacy of the 2008 and 2009 IIV3s against influenza due to any strain was 42% (95% confidence interval [CI]: 30%, 52%), whereas vaccine efficacy against influenza due to the vaccine-matched strains was 60% (95% CI: 44%, 72%). Vaccine efficacy of the 2009 IIV3 against influenza due to the 2009 pandemic H1N1 strain was 38% (95% CI: 19%, 53%). No vaccine-related deaths or serious adverse events were reported. Solicited local and systemic adverse events were more frequent in IIV3 recipients than placebo recipients (local: IIV3 74.6% vs placebo 20.4%, p<0.001; systemic: IIV3 46.6% vs placebo 39.1%, p<0.001).

CONCLUSIONS

The 2008 and 2009 IIV3s were efficacious against influenza due to seasonal influenza strains and the 2009 IIV3 demonstrated moderate efficacy against influenza due to the 2009 pandemic H1N1 strain. Funded by CSL Limited, ClinicalTrials.gov identifier NCT00562484.

Harmonising Reference Intervals for Three Calculated Parameters used in Clinical Chemistry

For more than a decade there has been a global effort to harmonise all phases of the testing process, with particular emphasis on the most frequently utilised measurands. In addition, it is recognised that calculated parameters derived from these measurands should also be a target for harmonisation. Using data from the Aussie Normals study we report reference intervals for three calculated parameters: serum osmolality, serum anion gap and albumin-adjusted serum calcium. The Aussie Normals study was an a priori study that analysed samples from 1856 healthy volunteers. The nine analytes used for the calculations in this study were measured on Abbott Architect analysers. The data demonstrated normal (Gaussian) distributions for the albumin-adjusted serum calcium, the anion gap (using potassium in the calculation) and the calculated serum osmolality (using both the Bhagat et al. and Smithline and Gardner formulae). To assess the suitability of these reference intervals for use as harmonised reference intervals, we reviewed data from the Royal College of Pathologists of Australasia/Australasian Association of Clinical Biochemists (RCPA/AACB) bias survey. We conclude that the reference intervals for the calculated serum osmolality (using the Smithline and Gardner formulae) may be suitable for use as a common reference interval. Although a common reference interval for albumin-adjusted serum calcium may be possible, further investigations (including a greater range of albumin concentrations) are needed. This is due to the bias between the Bromocresol Green (BCG) and Bromocresol Purple (BCP) methods at lower serum albumin concentrations. Problems with the measurement of Total CO2 in the bias survey meant that we could not use the data for assessing the suitability of a common reference interval for the anion gap. Further study is required.

Heterogeneity of Human Neutrophil CD177 Expression Results from CD177P1 Pseudogene Conversion

Most humans harbor both CD177neg and CD177pos neutrophils but 1-10% of people are CD177null, placing them at risk for formation of anti-neutrophil antibodies that can cause transfusion-related acute lung injury and neonatal alloimmune neutropenia. By deep sequencing the CD177 locus, we catalogued CD177 single nucleotide variants and identified a novel stop codon in CD177null individuals arising from a single base substitution in exon 7. This is not a mutation in CD177 itself, rather the CD177null phenotype arises when exon 7 of CD177 is supplied entirely by the CD177 pseudogene (CD177P1), which appears to have resulted from allelic gene conversion. In CD177 expressing individuals the CD177 locus contains both CD177P1 and CD177 sequences. The proportion of CD177hi neutrophils in the blood is a heritable trait. Abundance of CD177hi neutrophils correlates with homozygosity for CD177 reference allele, while heterozygosity for ectopic CD177P1 gene conversion correlates with increased CD177neg neutrophils, in which both CD177P1 partially incorporated allele and paired intact CD177 allele are transcribed. Human neutrophil heterogeneity for CD177 expression arises by ectopic allelic conversion. Resolution of the genetic basis of CD177null phenotype identifies a method for screening for individuals at risk of CD177 isoimmunisation.

Relation of Habitual Chocolate Consumption to Arterial Stiffness in a Community-Based Sample: Preliminary Findings

BACKGROUND

The consumption of chocolate and cocoa has established cardiovascular benefits. Less is known about the effects of chocolate on arterial stiffness, a marker of subclinical cardiovascular disease. The aim of this study was to investigate whether chocolate intakes are independently associated with pulse wave velocity (PWV), after adjustment for cardiovascular, lifestyle and dietary factors.

METHODS

Prospective analyses were undertaken on 508 community-dwelling participants (mean age 61 years, 60% women) from the Maine-Syracuse Longitudinal Study (MSLS). Habitual chocolate intakes, measured using a food frequency questionnaire, were related to PWV, measured approximately 5 years later.

RESULTS

Chocolate intake was significantly associated with PWV in a non-linear fashion with the highest levels of PWV in those who never or rarely ate chocolate and lowest levels in those who consumed chocolate once a week. This pattern of results remained and was not attenuated after multivariate adjustment for diabetes, cardiovascular risk factors and dietary variables (p = 0.002).

CONCLUSIONS

Weekly chocolate intake may be of benefit to arterial stiffness. Further studies are needed to explore the underlying mechanisms that may mediate the observed effects of habitual chocolate consumption on arterial stiffness.

Sensitivity of blood lipids to changes in adiposity, exercise, and diet in children

PURPOSE

This study aims to determine whether blood lipids in healthy preadolescent children are sensitive to normally occurring changes in percent body fat, physical activity (PA), cardiorespiratory fitness (CRF), and macronutrient intake.

METHODS

Repeated measurements of fasting serum LDL cholesterol, HDL cholesterol, and triglycerides (TG); percent body fat (dual-energy x-ray absorptiometry); PA (pedometers); CRF (multistage run); and carbohydrate, sugar, and fat intake (dietary recall and record) were carried out in 469 children (51% girls) age 8, 10, and 12 yr.

RESULTS

Longitudinal relationships in boys showed that, for every one-unit increase in percent body fat, there was a 1.3% (95% CI, 0.9-1.8; P < 0.001) increase in LDL cholesterol; among girls, the increase was 0.8% (95% CI, 0.3-1.2; P = 0.003). In addition, we found a positive longitudinal relationship between TG and percent body fat (P < 0.001) in girls, and a negative longitudinal relationship between HDL cholesterol and percent body fat (P = 0.03) in boys. There were also longitudinal relationships between TG and CRF in both sexes (P < 0.05), but these were not sustained upon adjustment for percent body fat. Although cross-sectional relationships occurred in girls for both HDL cholesterol and TG with PA (P < 0.05), we found no evidence of any relationships between lipids and fat or sugar intake. By age 12 yr, LDL cholesterol was elevated (>3.36 mmol·L) in 16% and 20% of girls and boys, respectively.

CONCLUSIONS

Blood lipids in preadolescent children appear sensitive to normal changes occurring in their percent body fat and, thus, fitness. Our data support early attention to body composition in community strategies designed to prevent cardiovascular disease in later life.

Guiding Hypertension Management Using Central Blood Pressure: Effect of Medication Withdrawal on Left Ventricular Function

BACKGROUND

Central blood pressure (BP) is an acknowledged contributor to end-organ damage and independent determinant of prognosis. Primary analysis from the BPGUIDE study demonstrated no detriment on left ventricular (LV) structure from central BP-guided hypertension management, despite significant medication withdrawal. However, the effect of this on LV function has not been investigated. In this study, we sought to investigate the impact of central BP-guided hypertension management on LV systolic and diastolic performance.

METHODS

A total of 286 enrollees with uncomplicated hypertension were randomized to therapeutic decisions guided by best-practice usual care (UC) or, in addition, by central BP intervention (CBP) for 12 months. Each participant underwent baseline and follow-up 2-dimensional echocardiography, with assessment undertaken by an expert blinded to participant allocation.

RESULTS

Antihypertensive medication quantity remained unchanged for UC but significantly decreased with intervention. However, no significant between-group differences were noted for changes during follow-up in both brachial and central BP, as well as other central hemodynamic parameters: augmentation index and augmented pressure. Similarly, there were no differences between groups in parameters of LV diastolic function: tissue e' velocity (∆UC vs. ∆CBP; P = 0.27) and E/e' ratio (∆UC vs. ∆CBP; P = 0.60), and systolic parameters: LV longitudinal strain (∆UC vs. ∆CBP; P = 0.55), circumferential strain (∆UC vs. ∆CBP; P = 0.79), and ejection fraction (∆UC vs. ∆CBP; P = 0.15).

CONCLUSIONS

Hypertension management guided by central BP, resulting in significant withdrawal of medication to maintain appropriate BP control, had no adverse effect on LV systolic or diastolic function. Clinical trials registration: Australia New Zealand Clinical Trial Registry Number ACTRN12608 000041358.

Categorising major cardiovascular disease hospitalisations from routinely collected data

Objectives and importance of the study: Routine hospital administrative data provide an important source of information about cardiovascular disease (CVD) for health statistics reporting, health services and research. How such conditions are classified and grouped has implications for the use and interpretation of these data. International Classification of Diseases (ICD) diagnosis codes from hospital data collections are often used to classify CVD, but there is little published evidence on the most appropriate ways to use these codes to categorise CVD in a way that maximises the usefulness of hospital data for reporting and research. In particular, ICD codes under 'Diseases of the circulatory system' (I00-I99) are often grouped together into a general CVD category. However, this category is heterogeneous and combines common severe atherosclerotic and thrombotic CVDs (such as myocardial infarction and pulmonary embolism) with common, less severe and pathologically dissimilar conditions (such as varicose veins and haemorrhoids). In addition, hospital data collections contain a range of data fields, including those relating to primary and additional diagnoses and those relating to procedures. All of these have the potential to contribute valuable information on CVD. This paper proposes a pragmatic approach to using ICD diagnosis codes and procedure codes to capture major atherosclerotic and arteriovenous thromboembolic and related CVD.

METHODS

We reviewed the ICD diagnosis codes and procedure codes and developed an algorithm for classifying and categorising major CVD diagnoses. This approach was then applied to linked hospitalisation data from individuals participating in the 45 and Up Study, a cohort study of 267 153 New South Wales residents aged 45 and over, to investigate the implications of the proposed approach for quantifying CVD.

RESULTS

Large differences were observed in the numbers of events in grouped CVD outcomes, depending on the methods used.

CONCLUSIONS

In cases where the reporting and research interest relates to incident disease, it may be appropriate to prioritise specific disease categories and pathological homogeneity.

Impact of CARDIOrespiratory FITness on Arrhythmia Recurrence in Obese Individuals With Atrial Fibrillation: The CARDIO-FIT Study

BACKGROUND

Obesity begets atrial fibrillation (AF). Although cardiorespiratory fitness is protective against incident AF in obese individuals, its effect on AF recurrence or the benefit of cardiorespiratory fitness gain is unknown.

OBJECTIVES

This study sought to evaluate the role of cardiorespiratory fitness and the incremental benefit of cardiorespiratory fitness improvement on rhythm control in obese individuals with AF.

METHODS

Of 1,415 consecutive patients with AF, 825 had a body mass index ≥27 kg/m(2) and were offered risk factor management and participation in a tailored exercise program. After exclusions, 308 patients were included in the analysis. Patients underwent exercise stress testing to determine peak metabolic equivalents (METs). To determine a dose response, cardiorespiratory fitness was categorized as: low (<85%), adequate (86% to 100%), and high (>100%). Impact of cardiorespiratory fitness gain was ascertained by the objective gain in fitness at final follow-up (≥2 METs vs. <2 METs). AF rhythm control was determined using 7-day Holter monitoring and AF severity scale questionnaire.

RESULTS

There were no differences in baseline characteristics or follow-up duration between the groups defined by cardiorespiratory fitness. Arrhythmia-free survival with and without rhythm control strategies was greatest in patients with high cardiorespiratory fitness compared to adequate or low cardiorespiratory fitness (p < 0.001 for both). AF burden and symptom severity decreased significantly in the group with cardiorespiratory fitness gain ≥2 METs as compared to <2 METs group (p < 0.001 for all). Arrhythmia-free survival with and without rhythm control strategies was greatest in those with METs gain ≥2 compared to those with METs gain <2 in cardiorespiratory fitness (p < 0.001 for both).

CONCLUSIONS

Cardiorespiratory fitness predicts arrhythmia recurrence in obese individuals with symptomatic AF. Improvement in cardiorespiratory fitness augments the beneficial effects of weight loss. (Evaluating the Impact of a Weight Loss on the Burden of Atrial Fibrillation [AF] in Obese Patients; ACTRN12614001123639).