ABSTRACT
AIMS: With improving cancer survivorship, cardiovascular disease (CVD) has become a leading cause of death in breast cancer (BC) survivors. At present, there is no prospectively validated, contemporary risk assessment tool specific to this patient cohort. Accordingly, we sought to investigate long-term cardiovascular outcomes in early-stage BC patients utilising a well characterised database at a quaternary referral centre. With the assembly of this cohort, we have derived a BC cardiovascular risk index titled the 'CRIB (Cardiovascular Risk Index in Breast Cancer)' to estimate the risk of a major adverse cardiovascular event (MACE) in women undergoing treatment for BC. METHODS: A retrospective cohort study was conducted examining all female patients aged ≥18 years of age who underwent treatment for early-stage BC at a cancer centre in Melbourne, Australia, between 2009 and 2019. The primary aim of this study was to assess causes and predictors of MACE. RESULTS: A total of 1,173 women with early-stage BC were included. During a median follow-up of 4.4 (1.8-6.7) years, 80 (6.8%) women experienced a MACE. These women were more likely to be older, with a high burden of cardiovascular risk factors and were more likely to have a history of established coronary artery disease (CAD) (p≤0.001 for all). A CRIB ≥3 (2 points: renal impairment, 1 point: age ≥65 years, body mass index [BMI]>27, diabetes, hypertension, history of smoking) demonstrated moderate discrimination (c-statistic 0.75) with appropriate calibration. A CRIB ≥3, which represented 23.9% of our cohort, was associated with a high risk of MACE (odds ratio [OR] 17.85, 95% confidence interval [CI] 6.36-50.05; p<0.001). A total of 138 (11.8%) women died during the study period. Mortality was significantly higher in patients who experienced a MACE (HR 2.72, 95%CI 1.75-4.23; p<0.001). CONCLUSION: Cardiovascular risk stratification at the time of BC diagnosis using the novel CRIB may help guide surveillance and the use of cardioprotective therapies as well as identify those who require long-term cardiac follow-up.
Subject(s)
Breast Neoplasms , Mobile Applications , Humans , Female , Smartphone , Breast Neoplasms/therapy , Walking , BreastABSTRACT
INTRODUCTION: Breast cancer survivors are at greater risk for cardiovascular-related mortality compared to women without breast cancer. Accordingly, attention to reducing the risk of cardiovascular disease must be a priority in the long-term management of these patients. With the exponential rise in cancer survivors, there is a need for innovative cardio-oncology programs. This paper describes the study design of a randomised controlled trial assessing the effectiveness of a smartphone-based cardiovascular risk reduction program in improving physical activity and cardiovascular health in patients undergoing treatment for breast cancer. METHODS AND ANALYSIS: The aim of this study is to assess the efficacy and usability of a smartphone-based model of care for exercise promotion, cardiovascular risk reduction and community engagement in women undergoing treatment for breast cancer. This will be achieved by testing our personalised smartphone application "BreastMate", as an adjunct to standard care in a single-blinded, parallel, randomised controlled trial. The primary outcome of the trial is change in exercise capacity, as measured by the 6-minute walk test distance at 12 months compared to baseline. Secondary endpoints include improvements in cardiovascular risk factor status and quality of life, received dose intensity of chemotherapy and major adverse cardiovascular events. ETHICS: Multicentre ethical approval has been granted by the Austin Hospital (HREC/47081/Austin/2018). DISSEMINATION OF RESULTS: The analysed results will be published in a peer reviewed journal on completion of the clinical trial. REGISTRATION DETAILS: SMART-BREAST has been prospectively registered with the Australia and New Zealand Clinical Trials Registry (ANZCTR12620000007932).
