Large-Scale Proteomics Identifies Novel Biomarkers and Circulating Risk Factors for Aortic Stenosis

BACKGROUND

Limited data exist regarding risk factors for aortic stenosis (AS). The plasma proteome is a promising phenotype for discovery of novel biomarkers and potentially causative mechanisms.

OBJECTIVES

The aim of this study was to discover novel biomarkers with potentially causal associations with AS.

METHODS

We measured 4,877 plasma proteins (SomaScan aptamer-affinity assay) among ARIC (Atherosclerosis Risk In Communities) study participants in mid-life (visit 3 [V3]; n = 11,430; age 60 ± 6 years) and in late-life (V5; n = 4,899; age 76 ± 5 years). We identified proteins cross-sectionally associated with aortic valve (AV) peak velocity (AVmax) and dimensionless index by echocardiography at V5 and with incident AV-related hospitalization after V3 with the use of multivariable linear and Cox proportional hazard regression. We assessed associations of candidate proteins with changes in AVmax over 6 years and with AV calcification with the use of cardiac computed tomography, replicated analysis in an independent sample, performed Mendelian randomization, and evaluated gene expression in explanted human AV tissue.

RESULTS

Fifty-two proteins cross-sectionally were associated with AVmax and dimensionless index at V5 and with risk of incident AV-related hospitalization after V3. Among 3,413 participants in the Cardiovascular Health Study, 6 of those proteins were significantly associated with adjudicated moderate or severe AS, including matrix metalloproteinase 12 (MMP12), complement C1q tumor necrosis factor-related protein 1 (C1QTNF1), and growth differentiation factor-15. MMP12 was also associated with greater increase in AVmax over 6 years, greater degree of AV calcification, and greater expression in calcific compared with normal or fibrotic AV tissue. C1QTNF1 had consistent potential causal effects on both AS and AVmax according to Mendelian randomization analysis.

CONCLUSIONS

These findings identify MMP12 as a potential novel circulating biomarker of AS risk and C1QTNF1 as a new putative target to prevent AS progression.

Association of interleukin-6 and interleukin-18 with cardiovascular disease in older adults: Atherosclerosis Risk in Communities study

AIMS

Interleukin-6 (IL-6) and interleukin-18 (IL-18), important cytokines implicated in atherosclerosis and inflammaging, were assessed for associations with global cardiovascular disease (CVD), atrial fibrillation (AF), and death in older adults.

METHODS AND RESULTS

Participants from Atherosclerosis Risk in Communities study Visit 5 (mean age 75.4 ± 5.1 years) with IL-6 and IL-18 measurements were included (n = 5672). Cox regression models were used to assess associations of IL-6 and IL-18 with coronary heart disease (CHD), ischaemic stroke, heart failure (HF) hospitalization, global CVD (composite of CHD, stroke, and HF), AF, and all-cause death. Over a median follow-up of 7.2 years, there were 1235 global CVD events, 530 AF events, and 1173 deaths. Higher IL-6 [hazard ratio (HR) 1.57, 95% confidence interval (CI) 1.44-1.72 per log unit increase] and IL-18 (HR 1.13, 95% CI 1.01-1.26) were significantly associated with global CVD after adjustment for cardiovascular risk factors. Association between IL-6 and global CVD remained significant after further adjustment for high-sensitivity C-reactive protein (hs-CRP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and high-sensitivity troponin T (hs-TnT) but was no longer significant for IL-18 after further adjustments. Interleukin-6 was also associated with increased risk for CHD, HF, and AF after adjustment for covariates. Both IL-6 and IL-18 were associated with increased risk for all-cause death independent of cardiovascular risk factors and other biomarkers.

CONCLUSION

Among older adults, both IL-6 and IL-18 were associated with global CVD and death. The association between IL-6 with CVD appears to be more robust and was independent of hs-CRP, NT-proBNP, and hs-TnT.

Did COVID-19 Have an Impact on Incident Leaning? Implications for Patient Safety

PURPOSE/OBJECTIVE(S)

The Ottawa Hospital's Radiation Oncology program maintains the Incident Learning System (ILS) - a quality assurance program that consists of report submissions of errors and near misses arising from all major domains of radiation. In March 2020, the department adopted workflow changes to optimize patient and provider safety during the COVID-19 pandemic. The purpose of this study was to analyze the number and type of ILS submissions pre- and post-pandemic precautions to assess the impact of COVID-19-related workflow changes.

MATERIALS/METHODS

ILS data was collected over seven one-year time periods between March 2016 and February 2023, where COVID-19-related workflow changes were initiated March 2020, and lifted in March 2022. All incidents in the system were previously investigated as per clinical practice. Incidents were analyzed for the number of reports submitted and number of actual versus potential incidents as compared to previous years. Origin and detection domains were tabulated for each period under consideration, as were the root causes of the incidents.

RESULTS

With the onset of COVID-19-related workflow changes, the total number of ILS submissions were reduced by 25%. Similarly, there were 30% fewer ILS submissions per number of treatment courses compared to pre-pandemic data. There was also an increase in the proportion of "treatment planning" ILS submissions and a 50% reduction in the proportion of "decision to treat" ILS submissions compared to previous years. Root cause analysis revealed there were more incidents attributable to "poor, incomplete, or unclear documentation" during the pandemic years. In the most recent year, as COVID-19 workflow changes have eased, the total number of ILS submissions has returned to the pre-pandemic baseline average.

CONCLUSION

During the pandemic years, workflow and staffing changes were associated with a decrease in the number of ILS submissions indicating less engagement with a vital component of quality assurance and therefore patient safety. In addition, significant changes observed regarding the types of submissions reported during the pandemic years are reflective of the unique challenges encountered during pandemic precautions. Continued engagement with ILS reporting is essential to the continued safety of the radiation oncology program, particularly during the dynamic COVID-19 pandemic or other periods of rapid change within a program.

Abstract P199: Proteomic Markers of Aortic Stenosis: The Atherosclerosis Risk in Communities Study

Introduction: Although prevalence of aortic stenosis (AS) is increasing, little is known regarding circulating proteins predictive of AS development.

Hypothesis: Novel circulating proteins associated with AS hemodynamics and clinical outcomes can be discovered using plasma proteomics.

Methods: In the community-based Atherosclerosis Risk in Communities study, we measured plasma proteomics using the SOMAscan aptamer-affinity assay (n=4,877 aptamers; Somalogic Inc.) at study Visits 3 (V3; 1992-94; n=11,430) and 5 (V5; 2011-2013; n=4,899). Multivariable linear regression was used to estimate cross-sectional associations of log-transformed proteins at V5 with aortic valve (AV) peak velocity (Vmax) assessed by protocol echocardiography at a false discovery rate (FDR) of <0.05. We then assessed the association of Vmax-related proteins at V3 with incident AV-related hospitalizations post-V3 using multivariable Cox proportional hazard models at FDR of <0.05. All models adjusted for cardiovascular risk factors and diseases at the time of visit.

Results: At V5 (age 76 ± 5 years; 43% male; 18% Black adults), 946 proteins were cross-sectionally associated with Vmax. At V3, (age 60 ± 6 years; 46% male; 21% Black), 84 of these were associated with risk of AS-related hospitalization post-V3 (median follow-up 22.2 [IQR 14.4 - 24.8] years, n=912 events). Of these 84 proteins, 52 were also cross-sectionally associated with the Dimensionless index (DI) at V5. Hierarchical clustering based on V5 AV hemodynamic indices identified one cluster of 14 proteins associated with lower hemodynamic AS severity and risk of AV-related hospitalization ( Figure ). Proteins in the remaining three clusters were associated with higher Vmax, lower DI, and higher risk of AV-related hospitalization. The nine proteins in cluster 4 were also associated with lower indexed AV area.

Conclusion: We identified 52 circulating proteins with robust associations with AV hemodynamics and hospitalization risk, providing potential novel biomarkers for AS risk.

Mid- to Late-Life Inflammation and Risk of Cardiac Dysfunction, HFpEF and HFrEF in Late Life

BACKGROUND

Epidemiologic data supporting the association of accumulated inflammation from mid- to late life with late-life risk of cardiac dysfunction and heart failure (HF) is limited.

METHODS AND RESULTS

Among 4011 participants in the Atherosclerosis Risk in Communities study who were free of prevalent cardiovascular disease at study Visit 5, accumulated inflammation was defined as time-averaged high-sensitivity c-reactive protein (hsCRP) over 3 visits spanning 1990 to 2013. Associations with left ventricular (LV) function at Visit 5 and with incident adjudicated HF post Visit 5 were assessed using linear and Cox regression, adjusting for demographics and comorbidities. Higher accumulated hsCRP was associated with greater LV mass index, lower e', higher E/e', and higher adjusting for demographics (all P ≤0.01), but only with higher pulmonary artery systolic pressure after adjustment for comorbidities (P = 0.024). At 5.3 ± 1.2 year follow-up, higher accumulated hsCRP was associated with greater risk of incident HF (HR 1.31 [95% CI 1.18-1.47], P < 0.001), HFrEF (1.26 [1.05-1.52], P = 0.01), and HFpEF (1.30 [1.11-1.53], P = 0.001) in demographic-adjusted models, but not after adjustment for comorbidities (all P > 0.10). Only Visit 5 hsCRP remained associated with incident HF (1.12 [1.02-1.24], P = 0.02) after full adjustment.

CONCLUSIONS

Greater accumulated inflammation is associated with worse LV function and heightened HF risk in late-life. These relationships are attenuated after adjusting for HF risk factors.

Feasibility of Virtual Optimization of Guideline Directed Medical Therapy in Hospitalized Patients with HFrEF During the Covid-19 Pandemic: The IMPLEMENT-HF Pilot Study

Introduction

Implementation of GDMT for HFrEF remains low. We assessed the feasibility of a virtual GDMT Team for optimization of GDMT during hospitalization for non-CV conditions.

Hypothesis

A GDMT Team will improve GDMT optimization compared with usual care.

Methods

Consecutive hospitalized patients with HFrEF≤40% were prospectively identified. Patients with critical illness, cardiology consult, de-novo HF, COVID-19 & SBP ≤90mmHg were excluded. February 3 to March 1, 2020 served as a pre-intervention period during which patients were screened, but did not receive GDMT Team interventions. From March 2 to June 21, 2020, a pharmacist-physician team provided up to 1 suggestion daily for GDMT optimization (evidence-based ß-blockers, ACEi/ARB/ARNI, & MRA) to treating teams based on an evidence-based algorithm.

The primary outcome of a composite GDMT optimization score, the net of positive therapeutic changes (+1 for new initiations/uptitrations) & negative therapeutic changes (-1 for discontinuations/downtitrations) during hospitalization, was compared between the pre- vs. post-intervention periods. Multivariable linear regression models were built adjusting associations for clinical factors. Safety outcomes requiring intervention or GDMT downtitration were identified.

Results

Of 187 encounters, 84 (45%) met eligibility criteria: 28 pre-intervention, 56 post-intervention. Mean age was 68±11 yrs, 70% men, and 61% White. Of 88 GDMT Team suggestions, 49 (56%) were followed by discharge. During the intervention, cumulative COVID-19 hospitalizations rose from 0 to 11085 in MA.

Mean GDMT optimization score was -0.14 (95% CI: -0.58 to +0.30) pre-intervention & +0.64 (95% CI: +0.35 to +0.93) post-intervention (P=0.004). In a model inclusive of demographics, comorbidities, vital signs, potassium levels, eGFR, & LVEF, the intervention was the only factor associated with higher GDMT optimization score (β coeff 0.89; P=0.008). Safety events included 1 instance each of AKI, hyperkalemia, bradycardia, & hypotension.

Conclusion

Admission for non-CV conditions is a feasible setting for GDMT optimization. A virtual GDMT Team was associated with improved GDMT; this implementation strategy warrants testing in a prospective RCT.

Early changes in N-terminal pro-brain natriuretic peptide levels predict new-onset heart failure in patients with STEMI

BACKGROUND

Previous studies suggested that N-terminal pro-brain natriuretic peptide (NT-proBNP) level is a powerful independent predictor of death or heart failure (HF) when measured at admission in patients with chest pain or acute coronary syndrome. Little is known about the role of NT-proBNP level measured during a hospitalization for ST segment elevation myocardial infarction (STEMI) in predicting clinical outcomes. We evaluated the optimal NT-proBNP timing (admission, 72 hours, or delta [Δ] NT-proBNP [72 hours minus admission]) to predict 1-year new-onset HF in STEMI patients.

METHODS

We measured NT-proBNP levels at admission and 72 hours in 72 patients with STEMI. HF events were adjudicated and defined as hospitalization for HF or need for new initiation of a loop diuretic at 1-year follow-up. Values are presented as medians and interquartile range or frequencies (%) as appropriate. Cox regression analysis was used to determine predictors of adverse events. A receiver-operative-curve was constructed to identify the discriminative value and optimal cut-off points for NT-proBNP.

RESULTS

Patients (age 56 [49-64] years, males 59 [82%]) were followed for a median duration of 365 [180-365] days. HF events were recorded in 9 (12.5%) patients. NT-proBNP values at admission, 72 hours, and ΔNT-proBNP were 89 (26-268) pg/mL, 452 (223-1064) pg/mL, and 283 (68-686) pg/mL, respectively. NT-proBNP at 72 hours and ΔNT-proBNP, but not admission NT-proBNP predicted new-onset HF events at follow-up (P=0.03, P=0.002 and P=0.89, respectively). The optimal area under the curve of 0.771 (95%, CI [0.630-0.912], P= 0.009) and cut-off value of 830 pg/mL (sensitivity 79%; specificity 76%) were found for NT-proBNP at 72 hours. The Kaplan-Meier survival curves for NT-proBNP at 72 hours dichotomized above and below this cut-off value, confirmed NT-proBNP at 72 hours >830 pg/mL as predictive of HF events (log-rank statistic = 8.688, P=0.003).

CONCLUSIONS

NT-proBNP level at 72 hours and ΔNT-proBNP (72 hours minus admission), but not at time of admission, predicted HF events in patients following STEMI.

Determinants of Cardiorespiratory Fitness in Patients with Heart Failure Across a Wide Range of Ejection Fractions

Impaired cardiorespiratory fitness (CRF) in heart failure (HF) is influenced by a complex array of cardiac and extracardiac factors. The study aimed to identify clinical determinants of CRF measured as peak oxygen consumption (peak VO₂) in HF patients, and to determine a peak VO₂ prediction model using regression equations. Retrospective analysis of 200 HF patients who completed treadmill cardiopulmonary exercise testing and underwent Doppler echocardiography and/or biomarker analysis on the same day was performed. After univariate linear regression analysis, a multivariate peak VO₂ prediction model was developed using significant variables in a stepwise linear regression analysis. In subjects with repeated testing, Pearson's correlation was used to assess correlations between measured and predicted change in peak VO₂ (Δpeak VO₂) over time. Mean age was 57 years, with 55% being male. Stepwise linear regression was used to generate a weighted model for peak VO₂: 30.895 + (-0.112•age[years]) + (0.296•hemoglobin [g/dl]) + (-0.101•E/e'[unit change]) + (-0.202• body mass index [kg/m²]) + (-0.593• N-terminal pro-brain natriuretic peptide [log_N pg/ml])) + (-1.349•CRP [log mg/L]). Predicted peak VO₂ correlated strongly with measured peak VO₂ in HF with reduced ejection fraction and HF with preserved ejection fraction patients (r = +0.63, p <0.001; r = +0.64, p <0.001, respectively). Predicted Δpeak VO₂ correlated with measured Δpeak VO₂ (r = +0.23, p <0.001). In conclusion, in patients with HF across a wide range of left ventricular ejection fraction, age, systemic inflammation, oxygen carrying capacity, obesity, and elevated filling pressures are the strongest predictors of impaired CRF. The proposed CRF model allows prediction of peak VO₂ in HF patients and may be used to estimate peak VO₂ changes over time.

IL-1 Blockade in Patients With Heart Failure With Preserved Ejection Fraction

Background Enhanced inflammation may lead to exercise intolerance in heart failure with preserved ejection fraction. The aim of the current study was to determine whether IL (interleukin)-1 blockade with anakinra improved cardiorespiratory fitness in heart failure with preserved ejection fraction. Methods and Results Thirty-one patients with heart failure with preserved ejection fraction and CRP (C-reactive protein) >2 mg/L were randomized to anakinra (100 mg subcutaneously daily, N=21) or placebo (N=10) for 12 weeks. We measured peak oxygen consumption (Vo₂), ventilatory efficiency (V_E/Vco₂ slope), and high-sensitivity CRP and NT-proBNP (N-terminal pro-B-type natriuretic peptide) at 4, 12, and 24 weeks. Twenty-eight patients completed ≥2 visits, 18 women (64%), 27 (96%) obese. There were no differences in peak Vo₂ or V_E/Vco₂ slope between groups at baseline. Peak Vo₂ was not changed after 12 weeks of anakinra (from 13.6 [11.8-18.0] to 14.2 [11.2-18.5] mL·kg^-1·min^-1, P=0.89), or placebo (14.9 [11.7-17.2] to 15.0 [13.8-16.9] mL·kg^-1·min^-1, P=0.40), without significant between-group differences in changes at 12 weeks (-0.4 [95% CI, -2.2 to +1.4], P=0.64). V_E/Vco₂ slope was also unchanged with anakinra (from 28.3 [27.2-33.0] to 30.5 [26.3-32.8], P=0.97) or placebo (from 31.6 [27.3-36.9] to 31.2 [27.8-33.4], P=0.78), without significant between-group differences in changes at 12 weeks (+1.2 [95% CI, -1.8 to +4.3], P=0.97). Within the anakinra-treated patients, high-sensitivity CRP and NT-proBNP levels were lower at 4 weeks compared with baseline ( P=0.026 and P=0.022 versus placebo [between-group analysis], respectively). Conclusions Treatment with anakinra for 12 weeks failed to improve peak Vo₂ and V_E/Vco₂ slope in a group of obese heart failure with preserved ejection fraction patients. The favorable trends in high-sensitivity CRP and NT-proBNP with anakinra deserve exploration in future studies. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT02173548.

Omega-3 Red Blood Cell Content Is Associated with Fat Mass Index and Leptin in Subjects with Obesity and Heart Failure with Preserved Ejection Fraction (P21-001-19)

Objectives

Overweight and obesity affect 80% of patients with heart failure and preserved ejection fraction (HFpEF). Exercise intolerance is a cardinal manifestation of HFpEF and is associated with excess fat mass (FM). Dietary polyunsaturated fatty acids (PUFA) have been associated with lower FM. However, the relationship between Omega-3 (N-3) PUFA and FM in HFpEF remains unclear. Red blood cell membrane (RBC) N-3 and omega-6 (N-6) PUFA content may serve as better objective measures of intake than subject-reported data. We hypothesized that increased RBC omega-3 (N-3) content is associated with lower FM and leptin in subjects with obesity and HFpEF.

Methods

Twenty-four consecutive subjects with HFpEF underwent body composition measurement with bioelectrical impedance analysis to obtain FM Index (FMI; kg/m2) and venipuncture to obtain RBC total percentage of N-3 PUFA content (RBC N-3%) as well as the ratio of N-6 to N-3 PUFA (N-6/N-3 ratio).

Results

Fourteen subjects were female (58%) with a median age of 53 (interquartile range [IQR] 48–63). Median BMI was 42.4 kg/m2 (38.1–47.4) and FMI was 18.7 kg/m2 (14.2–22.7). Median leptin was 82.5 ng/mL (63.5–116.5), RBC N-3% was 7.4% (6.6–8.9), and N-6/N-3 ratio was 5.00 (4.03–5.70). RBC N-3% was inversely associated with FMI (r = −0.406, P = 0.049), while N-6/N-3 ratio was positively associated with FMI (r = +0.472, P = 0.020) (Figure 1A and B). N-6/N-3 ratio was also associated with leptin (r = +0.462, P = 0.023), while RBC N-3% presented an inverse trend with leptin (r = −0.388, r = 0.061) (Figure 1C and D).

Conclusions

Higher percentage of N-3 PUFA in RBC membranes is associated with lower FMI and leptin in subjects with obesity and HFpEF. These findings suggest that increasing dietary N-3 intake and reducing N-6/N-3 ratio may protect against adiposity in HFpEF.

Funding Sources

This cross-sectional analysis was performed from baseline data of the DHART2 clinical trial (NCT02173548) and was funded by the NIH (1R34HL11348-01A1).

Supporting Tables, Images and/or Graphs

Primary and Secondary Diastolic Dysfunction in Heart Failure With Preserved Ejection Fraction

Approximately 50% of patients with symptoms and signs of heart failure have a left ventricular ejection fraction (LVEF) ≥50% and are often simply referred to as 'heart failure with preserved EF', 'HFpEF'. Many of such patients have HF secondary to specific cardiac conditions (i.e., valvular or pericardial disease) in which the symptoms and signs occur despite the LVEF being preserved due to diastolic dysfunction secondary to the underlying disease (secondary HFpEF), differently from those HFpEF patients in which the impaired LV filling is due to a primary diastolic dysfunction (primary HFpEF). When primary HFpEF patients are properly diagnosed, they appear to have a milder form of HF with a lower cardiovascular mortality compared with HFrEF and secondary HFpEF population, but a risk of HF hospitalization that is significantly higher than patients with similar cardiovascular risk factors but without the diagnosis of HFpEF. We herein review the diagnostic approach to HFpEF and present a differential diagnosis of HFpEF in a primary and secondary form.

Interleukin-1 Blockade in Recently Decompensated Systolic Heart Failure: Results From REDHART (Recently Decompensated Heart Failure Anakinra Response Trial)

BACKGROUND

An enhanced inflammatory response predicts worse outcomes in heart failure (HF). We hypothesized that administration of IL-1 (interleukin-1) receptor antagonist (anakinra) could inhibit the inflammatory response and improve peak aerobic exercise capacity in patients with recently decompensated systolic HF.

METHODS AND RESULTS

We randomly assigned 60 patients with reduced left ventricular ejection fraction (<50%) and elevated C-reactive protein levels (>2 mg/L), within 14 days of hospital discharge, to daily subcutaneous injections with anakinra 100 mg for 2 weeks, 12 weeks, or placebo. Patients underwent measurement of peak oxygen consumption (Vo₂ [mL/kg per minute]) and ventilatory efficiency (the VE/Vco₂ slope). Treatment with anakinra did not affect peak Vo₂ or VE/Vco₂ slope at 2 weeks. At 12 weeks, patients continued on anakinra showed an improvement in peak Vo₂ from 14.5 (10.5-16.6) mL/kg per minute to 16.1 (13.2-18.6) mL/kg per minute (P=0.009 for within-group changes), whereas no significant changes occurred within the anakinra 2-week or placebo groups. The between-groups differences, however, were not statistically significant. The incidence of death or rehospitalization for HF at 24 weeks was 6%, 31%, and 30%, in the anakinra 12-week, anakinra 2-week, and placebo groups, respectively (log-rank test P=0.10).

CONCLUSIONS

No change in peak Vo₂ occurred at 2 weeks in patients with recently decompensated systolic HF treated with anakinra, whereas an improvement was seen in those patients in whom anakinra was continued for 12 weeks. Additional larger studies are needed to validate the effects of prolonged anakinra on peak Vo₂ and rehospitalization for HF.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01936909.

Impaired myocardial relaxation with exercise determines peak aerobic exercise capacity in heart failure with preserved ejection fraction

Background

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome characterized by impaired exercise capacity due to shortness of breath and/or fatigue. Assessment of diastolic dysfunction at rest and with exercise may provide insight into the pathophysiology of exercise intolerance in HFpEF.

Aims

To measure echocardio‐Doppler‐derived parameters of diastolic function as they relate to various indices of aerobic exercise capacity in HFpEF.

Methods

We selected 16 subjects with clinically stable HFpEF, no evidence of volume overload, but impaired functional capacity by cardiopulmonary exercise testing [peak oxygen consumption (VO₂)]. We measured the transmitral E and A flow velocities, E/A ratio, and E deceleration time (DT) and tissue Doppler E′ velocity. We also indexed the E′ to the DT, as additional measure of impaired relaxation (E′_DT), and calculated the diastolic functional reserve index (DFRI), as the product of E′ at rest and change in E′ with exercise.

Results

E′ velocity, at rest and peak exercise, as well as the DFRI positively correlated with peak VO₂, whereas DT, E′_DT, and E/E′ with exercise inversely correlated with peak VO₂. Of note, the E′_DT at rest also significantly predicted E′ velocity at peak exercise (R = +0.81, P < 0.001). Exercise E′ was the only independent predictor of peak VO₂ at multivariable analysis (R = +0.67, P = 0.005).

Conclusions

The E′ velocity at peak exercise is a strong and independent predictor of aerobic exercise capacity as measured by peak VO₂ in patients with HFpEF, providing the link between abnormal myocardial relaxation with exercise and impaired aerobic exercise capacity in HFpEF.

Pilot evaluation of an adolescent risk and injury prevention programme incorporating curriculum and school connectedness components

School connectedness is an important protective factor for adolescent risk-taking behaviour. This study examined a pilot version of the Skills for Preventing Injury in Youth (SPIY) programme, combining teacher professional development (PD) for increasing school connectedness (connectedness component) with a risk and injury prevention curriculum for early adolescents (curriculum component). A process evaluation was conducted on the connectedness component, involving assessments of programme reach, participant receptiveness and initial use, and a preliminary impact evaluation was conducted on the combined connectedness and curriculum programme. The connectedness component was well received by teacher participants, who saw benefits for both themselves and their students. Classroom observation also showed that teachers who received PD made use of the programme strategies. Grade 8 students who participated in the SPIY programme were less likely to report violent behaviour at 6-month follow-up than were control students, and trends also suggested reduced transport injuries. The results of this research support the use of the combined SPIY connectedness and curriculum components in a large-scale effectiveness trial to assess the impact of the programme on students' connectedness, risk-taking and associated injuries.

PROSPER: a randomised comparison of surgical treatments for rectal prolapse

AIM

Rectal prolapse is a profoundly disabling condition, occurring mainly in elderly and parous women. There is no accepted standard surgical treatment, with previous studies limited in methodological quality and size. PROSPER aimed to address these deficiencies by comparing the relative merits of different procedures.

METHOD

In a pragmatic, factorial (2 × 2) design trial, patients could be randomised between abdominal and perineal surgery (i), and suture vs resection rectopexy for those receiving an abdominal procedure (ii) or Altemeier's vs Delorme's for those receiving a perineal procedure (iii). Primary outcome measures were recurrence of the prolapse, incontinence, bowel function and quality of life scores (Vaizey, bowel thermometer and EQ-5D) measured up to 3 years.

RESULTS

Two hundred and ninety-three patients were recruited: 49 were randomised between surgical approaches (i); 78 between abdominal procedures (ii); and 213 between perineal procedures (iii). Recurrence rates were higher than anticipated, but not significantly different in any comparison: Altemeier's vs Delorme's 24/102 (24%) and 31/99 (31%) [hazard ratio (HR) 0.81; 95% CI 0.47, 1.38; P = 0.4]; resection vs suture rectopexy 4/32 (13%) and 9/35 (26%) (HR 0.45; 95% CI 0.14, 1.46; P = 0.2); perineal vs abdominal 5/25 (20%) and 5/19 (26%) (HR 0.83; 95% CI 0.24, 2.86; P = 0.8). Vaizey, bowel thermometer and EQ-5D scores were not significantly different in any of the comparisons.

CONCLUSION

No significant differences were seen in any of the randomised comparisons, although substantial improvements from baseline in quality of life were noted following all procedures.

Anticoagulants: A Review of the Pharmacology, Dosing, and Complications

Anticoagulants remain the primary strategy for the prevention and treatment of thrombosis. Unfractionated heparin, low molecular weight heparin, fondaparinux, and warfarin have been studied and employed extensively with direct thrombin inhibitors typically reserved for patients with complications or those requiring intervention. Novel oral anticoagulants have emerged from clinical development and are expected to replace older agents with their ease of use and more favorable pharmacodynamic profiles. Hemorrhage is the main concerning adverse event with all anticoagulants. With their ubiquitous use, it becomes important for clinicians to have a sound understanding of anticoagulant pharmacology, dosing, and toxicity.

Efficacy and safety of novel anticoagulants compared with established agents

Dabigatran, rivaroxaban, and apixaban are novel oral anticoagulants that offer major advantages over existing agents. The onset of the anticoagulant effect of these agents is rapid. Each agent has a predictable anticoagulant response that eliminates the need for monitoring. Clinical trials have been completed with all three agents in the prevention and treatment of the three leading causes of cardiovascular death: myocardial infarction, stroke, and venous thromboembolism (VTE). Novel agents have shown reduced or similar rates of thrombosis, major bleeding, and adverse events when weighed against either low molecular weight heparin or warfarin. Additional trials are underway and more agents are in development. As a result, novel anticoagulants may impact physician prescribing practices and warrant consideration in patients requiring thrombosis management.

Abstract S4-4: SECRAB: The Optimal SEquencing of Adjuvant Chemotherapy (CT) and RAdiotherapy (RT) in Early Breast Cancer (EBC), Results of a UK Multicentre Prospective Randomised Trial

Background: The optimal sequence of CT and RT for women with EBC has yet to be defined. SECRAB aimed to determine i) if synchronous (Syn) CT-RT improves loco-regional relapse rates (LRR) and ii) whether the treatments could be given together without increased toxicity or compromising the dose intensity of either CT or RT. The first endpoint of this study is presented in this abstract. Methods: SECRAB was a prospective, randomised trial comparing sequential (Seq) to Syn CT-RT. Permitted RT schedules included 40Gy/15F over 3 weeks, 45Gy/20F over 4 weeks and 50Gy/25F over 5 weeks. Syn RT was administered between cycles 2 and 3 for CMF or 5 and 6 for anthracycline-CMF. Syn patients treated using 15F were treated predominantly using a sandwich schedule while those receiving &gt;15F were treated concurrently with CT. Seq RT was delivered on CT completion. Key eligibility criteria were completely excised EBC, fit for and requiring adjuvant CT and RT. The trial was powered to produce a definitive event driven analysis: 150 loco-regional relapses having 85% power to detect 4% 2-sided differences in the primary endpoint of overall LRR. Results: Between Jul 98 and Mar 04, 2296 women were randomised. Baseline characteristics were well balanced. 63% of patients were node positive indicating a high risk population. 2 patients did not receive CT and 23 did not receive RT. 5 patients in the latter group had a loco-regional relapse prior to planned RT (Seq n=3). With a median follow-up of 8.8 years there were 93 and 76 loco-regional relapses in the Seq and Syn arms and 5-year LRR were 7.4% (95% CI 5.9-9.1) and 5.4% (95% CI 4.2-7.0) respectively. There was no significant difference in overall LRR (HRSyn 0.82; 95% CI 0.6-1.1; p=0.19). There was a trend for benefit for Syn treatment which was consistent across different subgroups (grade, lymph node status, tumour size, vascular invasion and excision margin). In an unplanned subgroup analysis, a trend for benefit for Syn treatment was seen predominantly in patients with the presence of lymphovascular invasion (LRR 11.9% Seq vs 8.2% Syn) and also in patients with 0 and 1-3 positive nodes (LRR 7.8% Seq vs 5.2% Syn) but not in those with 4 or more positive nodes. Similar rates were observed for distant recurrences (22.2% vs 22.2%), contralateral recurrences (2.9% vs 2.7%), and new primary cancers (2.9% vs 2.6%) in the Seq and Syn arms respectively. There was also no significant difference in overall survival which was 83% and 82% in the Syn and Seq arms respectively at 5-years (HRSyn 0.99; 95% CI 0.8-1.2; p=0.87). Modest differences in acute skin toxicity and telangiectasia were observed between the two study arms. There was no difference in other late toxicities. The second primary endpoint of safety, toxicity and dose intensity is described in detail elsewhere (abstract no 850168). Conclusions: SECRAB is the largest sequencing trial in EBC to date. Delivering Syn CT-RT using CMF or anthracycline-CMF and a 3 weekly RT fractionation shortens the overall treatment time. Although not statistically significant there was a trend to improved locoregional control with Syn treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S4-4.

Abstract P4-11-05: Acute and Late Toxicity Results from the SECRAB Trial: The Optimal SEquencing of Adjuvant Chemotherapy (CT) and RAdiotherapy (RT) in Early Breast Cancer (EBC)

Background: SECRAB is a large multicentre randomised controlled trial designed to determine the optimal sequence of CT and RT for women with EBC. The second objective of this trial was to determine if CT and RT treatment modalities could be given together without increased toxicity or compromising either modality. See abstract no 851519 for details of CT and RT scheduling.

Methods: Data on acute skin reaction was collected on completion of RT and graded as mild, moderate or severe. Late toxicity data was collected annually and included lymphoedema, telangiectasia, severe subcutaneous fibrosis, brachial plexopathy, rib fracture, ischaemic heart disease, symptomatic lung fibrosis, and clinical radiation pneumonitis.

Results: Between Jul 98 and Mar 04, 2296 women were randomised. Acute toxicity data was collected on 2267 patients who received RT. The distribution of RT schedules was balanced across treatment arms, with the majority of patients (67%) receiving 40Gy/15F (15F). Significantly more patients in the Syn arm experienced a delay of &gt;10 days in CT delivery (11% vs 5%, p &lt; 0.0001). Very few patients experienced a &gt;7 days delay in RT in either arm (Syn n=12 vs Seq n=3). In a sub-set of 880 patients dose intensity of CT was not significantly different between the two arms. Percentage skin toxicities for the Syn and Seq arms respectively were: None 22.9 vs 36.3; Mild 52.4 vs 48.1; Moderate 20.2 vs 13.6; Severe 3.8 vs 1.1. A significantly (p &lt; 0.001) higher proportion of patients on the Syn arm suffered a moderate or severe skin reaction compared to those on the Seq arm. An unplanned exploratory analysis by duration of RT showed that patients receiving &gt;15F (45Gy/20F or 50Gy/25F) had a significantly worse acute skin reaction than those receiving 15F (25% vs 16%, p=&lt;0.001). 5 patients on the Syn arm were admitted to hospital as a result of a severe RT reaction, 3 received &gt;15F. Acute radiation pneumonitis was 0.3% in both arms (n=5 in total). Percentage late toxicities for the Syn and Seq arms respectively were not significantly different for: moderate/severe lymphoedema 6.1 (n=70) vs 5.5 (n=64); severe subcutaneous fibrosis 1.3 (n= 15) vs 0.6 (n=7); brachial plexopathy 0.2 (n=2) vs 0.1 (n=1); rib fracture 0.6 (n=7) vs 0.4 (n=5); ischaemic heart disease 0.4 (n=5) vs 0.4 (n=2); symptomatic lung fibrosis 0.3 (n=15) vs 0.3 (n=7); and late clinical radiation pneumonitis 0.1 (n=1) vs 0.1 (n=1). Howevermoderate/severe telangiectasia was 2.5% vs 1.3% in the Syn and Seq arms respectively (p =0.05). This difference was not seen in patients receiving 15F.

Conclusions: The delivery of Syn CT-RT in the adjuvant treatment of EBC is associated with an increase in acute skin toxicity however the percentage of severe reactions is less than 5%. These skin reactions were seen predominantly in patients treated with concurrent RT (&gt;15F). An increase in late skin telangiectasia was also seen in patients receiving &gt;15F. There was no difference in other late toxicities recorded. Syn CT-RT is feasible in the adjuvant treatment of EBC and does not result in a reduction in dose intensity of delivered CT. The optimal schedule is 40Gy/15F which is now the standard regime used in the UK.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-11-05.