Trends in referral to outpatient cardiac rehabilitation in the Hunter Region of Australia, 2002-2007

BACKGROUND: Cardiac rehabilitation (CR) is an underutilized evidence-based treatment. We described trends in referral to outpatient CR (OCR) and the factors associated with referral. DESIGN: Cross-sectional survey data provided by Hunter residents aged 20 years or older discharged from public hospitals in the region between 2002 and 2007 with an OCR eligible diagnosis were extracted from the Hunter New England Heart and Stroke Register database. METHODS: Trends in referral were determined using the chi test for trend. Factors associated with referral were examined using multiple logistic regression. RESULTS: Sixty-five percent (4971 of 7678) of patients provided sufficient data for inclusion in the analysis. Approximately half of the patients reported being referred to OCR. No increase over time was observed. Factors associated with referral were age less than 70 years, male sex, being married, urban residence, at least one admission to the tertiary referral hospital for cardiology, at least one admission for acute myocardial infarction, revascularization, no admissions for congestive heart failure, a self-reported history of high cholesterol, and no history of stroke or atrial fibrillation. CONCLUSION: Access to this treatment of proven benefit remained suboptimal despite the provision of new programs and expansion of existing programs. Automatic referral, which is recommended in Australia, should be standard practice.

Prediciton of emergency events: a multi-task multi-label learning approach

Prediction of patient outcomes is critical to plan resources in an hospital emergency department. We present a method to exploit longitudinal data from Electronic Medical Records (EMR), whilst exploiting multiple patient outcomes. We divide the EMR data into segments where each segment is a task, and all tasks are associated with multiple patient outcomes over a 3, 6 and 12 month period. We propose a model that learns a prediction function for each task-label pair, interacting through two subspaces: the first subspace is used to impose sharing across all tasks for a given label. The second subspace captures the task-specific variations and is shared across all the labels for a given task. The proposed model is formulated as an iterative optimization problems and solved using a scalable and efficient Block co-ordinate descent (BCD) method. We apply the proposed model on two hospital cohorts - Cancer and Acute Myocardial Infarction (AMI) patients collected over a two year period from a large hospital emergency department. We show that the predictive performance of our proposed models is significantly better than those of several state-of-the-art multi-task and multi-label learning methods.

Hierarchical Bayesian nonparametric models for knowledge discovery from electronic medical records

Electronic Medical Record (EMR) has established itself as a valuable resource for large scale analysis of health data. A hospital EMR dataset typically consists of medical records of hospitalized patients. A medical record contains diagnostic information (diagnosis codes), procedures performed (procedure codes) and admission details. Traditional topic models, such as latent Dirichlet allocation (LDA) and hierarchical Dirichlet process (HDP), can be employed to discover disease topics from EMR data by treating patients as documents and diagnosis codes as words. This topic modeling helps to understand the constitution of patient diseases and offers a tool for better planning of treatment. In this paper, we propose a novel and flexible hierarchical Bayesian nonparametric model, the word distance dependent Chinese restaurant franchise (wddCRF), which incorporates word-to-word distances to discover semantically-coherent disease topics. We are motivated by the fact that diagnosis codes are connected in the form of ICD-10 tree structure which presents semantic relationships between codes. We exploit a decay function to incorporate distances between words at the bottom level of wddCRF. Efficient inference is derived for the wddCRF by using MCMC technique. Furthermore, since procedure codes are often correlated with diagnosis codes, we develop the correspondence wddCRF (Corr-wddCRF) to explore conditional relationships of procedure codes for a given disease pattern. Efficient collapsed Gibbs sampling is derived for the Corr-wddCRF. We evaluate the proposed models on two real-world medical datasets - PolyVascular disease and Acute Myocardial Infarction disease. We demonstrate that the Corr-wddCRF model discovers more coherent topics than the Corr-HDP. We also use disease topic proportions as new features and show that using features from the Corr-wddCRF outperforms the baselines on 14-days readmission prediction. Beside these, the prediction for procedure codes based on the Corr-wddCRF also shows considerable accuracy.

Discordant age and sex-specific trends in the incidence of a first coronary heart disease event in Western Australia from 1996 to 2007

OBJECTIVE: To determine age- and sex-specific population trends in fatal and non-fatal first coronary heart disease (CHD) events in Western Australia from 1996 to 2007. DESIGN: Longitudinal retrospective population study. SETTING: State-wide population. PATIENTS: All residents aged 35-84 years during 1996-2007 who died or were hospitalised with a principal diagnosis of acute CHD. DATA SOURCES: Person-linked file of mortality and morbidity records. MAIN OUTCOME MEASURES: Age-standardised (35-84 years) and age-specific (35-54, 55-69, 70-84 years) rates by gender for a first CHD event were calculated with a 10-year lead-in period to define first events. RESULTS: From 1996 to 2007 there were 36 631 first CHD events, including 8518 (23%) fatal cases in those aged 35-84 years. Overall, age-adjusted rates for fatal first CHD declined 5.3%/year in men (95% CI -6.1% to -4.6%) and 6.5%/year in women (95% CI -7.5% to -5.5%). However, age-specific fatal first CHD rates were neutral in both men aged 35-54 years (0.1%/year; 95% CI -1.8% to 2.1%) and women of the same age, (-1.6%/year; 95% CI -5.6% to 2.5%). Age-specific trends in non-fatal CHD rates reflected the same trends in fatal CHD events in men and women, with rates reportedly increasing in women aged 35-54 years (2.5%/year (95% CI 1.1% to 3.9%). CONCLUSION: The age-specific decline in fatal and non-fatal first CHD rates in older men and women was not observed in those aged 35-54 years. These novel findings provide evidence for a levelling in the CHD incidence rates in younger adults and puts renewed importance on primary prevention in this group.

HealthMap: a cluster randomised trial of interactive health plans and self-management support to prevent coronary heart disease in people with HIV

BACKGROUND: The leading causes of morbidity and mortality for people in high-income countries living with HIV are now non-AIDS malignancies, cardiovascular disease and other non-communicable diseases associated with ageing. This protocol describes the trial of HealthMap, a model of care for people with HIV (PWHIV) that includes use of an interactive shared health record and self-management support. The aims of the HealthMap trial are to evaluate engagement of PWHIV and healthcare providers with the model, and its effectiveness for reducing coronary heart disease risk, enhancing self-management, and improving mental health and quality of life of PWHIV.

METHODS/DESIGN: The study is a two-arm cluster randomised trial involving HIV clinical sites in several states in Australia. Doctors will be randomised to the HealthMap model (immediate arm) or to proceed with usual care (deferred arm). People with HIV whose doctors are randomised to the immediate arm receive 1) new opportunities to discuss their health status and goals with their HIV doctor using a HealthMap shared health record; 2) access to their own health record from home; 3) access to health coaching delivered by telephone and online; and 4) access to a peer moderated online group chat programme. Data will be collected from participating PWHIV (n = 710) at baseline, 6 months, and 12 months and from participating doctors (n = 60) at baseline and 12 months. The control arm will be offered the HealthMap intervention at the end of the trial. The primary study outcomes, measured at 12 months, are 1) 10-year risk of non-fatal acute myocardial infarction or coronary heart disease death as estimated by a Framingham Heart Study risk equation; and 2) Positive and Active Engagement in Life Scale from the Health Education Impact Questionnaire (heiQ).

DISCUSSION: The study will determine the viability and utility of a novel technology-supported model of care for maintaining the health and wellbeing of people with HIV. If shown to be effective, the HealthMap model may provide a generalisable, scalable and sustainable system for supporting the care needs of people with HIV, addressing issues of equity of access.

A framework for mixed-type multi-outcome prediction with applications in healthcare

Health analysis often involves prediction of multiple outcomes of mixed-type. Existing work is restrictive to either a limited number or specific outcome types. We propose a framework for mixed-type multi-outcome prediction. Our proposed framework proposes a cumulative loss function composed of a specific loss function for each outcome type - as an example, least square (continuous outcome), hinge (binary outcome), poisson (count outcome) and exponential (non-negative outcome). Tomodel these outcomes jointly, we impose a commonality across the prediction parameters through a common matrix-Normal prior. The framework is formulated as iterative optimization problems and solved using an efficient Block coordinate descent method (BCD). We empirically demonstrate both scalability and convergence. We apply the proposed model to a synthetic dataset and then on two real-world cohorts: a Cancer cohort and an Acute Myocardial Infarction cohort collected over a two year period. We predict multiple emergency related outcomes - as example, future emergency presentations (binary), emergency admissions (count), emergency length-of-stay-days (non-negative) and emergency time-to-next-admission-day (non-negative). Weshow that the predictive performance of the proposed model is better than several state-of-the-art baselines.

A randomised, feasibility trial of a tele-health intervention for acute coronary syndrome patients with depression (‘MoodCare’): study protocol

Background Coronary heart disease (CHD) and depression are leading causes of disease burden globally and the two often co-exist. Depression is common after Myocardial Infarction (MI) and it has been estimated that 15-35% of patients experience depressive symptoms. Co-morbid depression can impair health related quality of life (HRQOL), decrease medication adherence and appropriate utilisation of health services, lead to increased morbidity and suicide risk, and is associated with poorer CHD risk factor profiles and reduced survival. We aim to determine the feasibility of conducting a randomised, multi-centre trial designed to compare a tele-health program (MoodCare) for depression and CHD secondary prevention, with Usual Care (UC).

Methods Over 1600 patients admitted after index admission for Acute Coronary Syndrome (ACS) are being screened for depression at six metropolitan hospitals in the Australian states of Victoria and Queensland. Consenting participants are then contacted at two weeks post-discharge for baseline assessment. One hundred eligible participants are to be randomised to an intervention or a usual medical care control group (50 per group). The intervention consists of up to 10 × 30-40 minute structured telephone sessions, delivered by registered psychologists, commencing within two weeks of baseline screening. The intervention focuses on depression management, lifestyle factors (physical activity, healthy eating, smoking cessation, alcohol intake), medication adherence and managing co-morbidities. Data collection occurs at baseline (Time 1), 6 months (post-intervention) (Time 2), 12 months (Time 3) and 24 months follow-up for longer term effects (Time 4). We are comparing depression (Cardiac Depression Scale [CDS]) and HRQOL (Short Form-12 [SF-12]) scores between treatment and UC groups, assessing the feasibility of the program through patient acceptability and exploring long term maintenance effects. A cost-effectiveness analysis of the costs and outcomes for patients in the intervention and control groups is being conducted from the perspective of health care costs to the government.

Discussion This manuscript presents the protocol for a randomised, multi-centre trial to evaluate the feasibility of a tele-based depression management and CHD secondary prevention program for ACS patients. The results of this trial will provide valuable new information about potential psychological and wellbeing benefits, cost-effectiveness and acceptability of an innovative tele-based depression management and secondary prevention program for CHD patients experiencing depression.

Depression as a predictor of work resumption following myocardial infarction (MI): a review of recent research evidence

Background Depression often coexists with myocardial infarction (MI) and has been found to impede recovery through reduced functioning in key areas of life such as work. In an era of improved survival rates and extended working lives, we review whether depression remains a predictor of poorer work outcomes following MI by systematically reviewing literature from the past 15 years.

Methods Articles were identified using medical, health, occupational and social science databases, including PubMed, OVID, Medline, Proquest, CINAHL plus, CCOHS, SCOPUS, Web of Knowledge, and the following pre-determined criteria were applied: (i) collection of depression measures (as distinct from 'psychological distress') and work status at baseline, (ii) examination and statistical analysis of predictors of work outcomes, (iii) inclusion of cohorts with patients exhibiting symptoms consistent with Acute Coronary Syndrome (ACS), (iv) follow-up of work-specific and depression specific outcomes at minimum 6 months, (v) published in English over the past 15 years. Results from included articles were then evaluated for quality and analysed by comparing effect size.

Results Of the 12 articles meeting criteria, depression significantly predicted reduced likelihood of return to work (RTW) in the majority of studies (n = 7). Further, there was a trend suggesting that increased depression severity was associated with poorer RTW outcomes 6 to 12 months after a cardiac event. Other common significant predictors of RTW were age and patient perceptions of their illness and work performance.

Conclusion Depression is a predictor of work resumption post-MI. As work is a major component of Quality of Life (QOL), this finding has clinical, social, public health and economic implications in the modern era. Targeted depression interventions could facilitate RTW post-MI.

Myocardial ischemia-reperfusion injury, antioxidant enzyme systems, and selenium : A review

Coronary heart disease (CHD) remains the greatest killer in the Western world, and although the death rate from CHD has been falling, the current increased prevalence of major risk factors including obesity and diabetes, suggests it is likely that CHD incidence will increase over the next 20 years. In conjunction with preventive strategies, major advances in the treatment of acute coronary syndromes and myocardial infarction have occurred over the past 20 years. In particular the ability to rapidly restore blood flow to the myocardium during heart attack, using interventional cardiologic or thrombolytic approaches has been a major step forward. Nevertheless, while 'reperfusion' is a major therapeutic aim, the process of ischemia followed by reperfusion is often followed by the activation of an injurious cascade. While the pathogenesis of ischemia-reperfusion is not completely understood, there is considerable evidence implicating reactive oxygen species (ROS) as an initial cause of the injury.

ROS formed during oxidative stress can initiate lipid peroxidation, oxidize proteins to inactive states and cause DNA strand breaks, all potentially damaging to normal cellular function. ROS have been shown to be generated following routine clinical procedures such as coronary bypass surgery and thrombolysis, due to the unavoidable episode of ischemia-reperfusion. Furthermore, they have been associated with poor cardiac recovery post-ischemia, with recent studies supporting a role for them in infarction, necrosis, apoptosis, arrhythmogenesis and endothelial dysfunction following ischemia-reperfusion. In normal physiological condition, ROS production is usually homeostatically controlled by endogenous free radical scavengers such as superoxide dismutase, catalase, and the glutathione peroxidase and thioredoxin reductase systems. Accordingly, targeting the generation of ROS with various antioxidants has been shown to reduce injury following oxidative stress, and improve recovery from ischemia-reperfusion injury.

This review summarises the role of myocardial antioxidant enzymes in ischemia-reperfusion injury, particularly the glutathione peroxidase (GPX) and the thioredoxin reductase (TxnRed) systems. GPX and TxnRed are selenocysteine dependent enzymes, and their activity is known to be dependent upon an adequate supply of dietary selenium. Moreover, various studies suggest that the supply of selenium as a cofactor also regulates gene expression of these selenoproteins. As such, dietary selenium supplementation may provide a safe and convenient method for increasing antioxidant protection in aged individuals, particularly those at risk of ischemic heart disease, or in those undergoing clinical procedures involving transient periods of myocardial hypoxia.

Effects of work-related sleep restriction on acute physiological and psychological stress responses and their interactions: A review among emergency service personnel

Emergency work can expose personnel to sleep restriction. Inadequate amounts of sleep can negatively affect physiological and psychological stress responses. This review critiqued the emergency service literature (e.g., firefighting, police/law enforcement, defense forces, ambulance/paramedic personnel) that has investigated the effect of sleep restriction on hormonal, inflammatory and psychological responses. Furthermore, it investigated if a psycho-physiological approach can help contextualize the significance of such responses to assist emergency service agencies monitor the health of their personnel. The available literature suggests that sleep restriction across multiple work days can disrupt cytokine and cortisol levels, deteriorate mood and elicit simultaneous physiological and psychological responses. However, research concerning the interaction between such responses is limited and inconclusive. Therefore, it is unknown if a psycho-physiological relationship exists and as a result, it is currently not feasible for agencies to monitor sleep restriction related stress based on psycho- physiological interactions. Sleep restriction does however, appear to be a major stressor contributing to physiological and psychological responses and thus, warrants further investigation.

Gender difference in treatment and mortality of patients with ST-segment elevation myocardial infarction admitted to Victorian public hospitals: A retrospective database study.

BACKGROUND: Death from acute coronary syndrome (ACS) is avoidable with early reperfusion therapy, however, evidence suggests inequity in women's ACS treatment within a number of international healthcare systems, when compared to men's. Research indicates mortality rates are higher in some age groups of women when compared to men for the sub-group of ACS known as ST-segment elevation myocardial infarction (STEMI). OBJECTIVE: To determine whether patient sex was associated with patterns of reperfusion treatment variation or increased inhospital mortality in patients with STEMI. METHODS: We undertook retrospective analyses on a government database for patients admitted to Victorian public hospitals with STEMI. Patients were categorised into two age groups: 18-64 and 65-84 years (inclusive), to determine whether patient sex and these age groups influenced treatment from 2005 to 2008 and mortality from 2005 to 2010. RESULTS: Both younger and older women received less frequent angioplasty with stent and more often received no reperfusion treatment than men in corresponding younger and older age groups (p=0.006 and p<0.001, respectively). Overall, women in both age groups were more likely to die inhospital than men from equivalent age groups with STEMI (p<0.001, both groups). CONCLUSIONS: Proportionately, both younger and older women received less interventional reperfusion therapy for STEMI than their male cohorts, and died more often during admission than men. Further research needs to be undertaken to verify the findings and causes, and guide future research to ensure application of evidence to treatment in patients with STEMI.

Gender difference in the use of coronary interventions for patients with acute coronary syndrome: experience from a major metropolitan hospital in Melbourne, Australia

BACKGROUND: Literature suggests an ongoing gender disparity in the use of coronary angiography and subsequent interventions among patients with acute coronary syndrome (ACS). OBJECTIVES: The study aimed to examine gender differences in the use of coronary interventions amongst patients with acute coronary syndrome (ACS) admitted to a major metropolitan hospital in Melbourne during the period 2009-2012. METHODS: We undertook a retrospective analysis of a hospital database of 2096 ACS patients. ACS included unstable angina (UA), ST-segment-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI). RESULTS: The mean age of the patients was 64.3 years and 624 (30%) were women. Half of them were diagnosed as NSTEMI, 23% as STEMI and 25% as UA. Compared to men, women were older at admission, less likely to be diagnosed with STEMI and less likely to smoke. No gender difference was observed for severe co-morbidities or use of coronary angiography. Women diagnosed with STEMI were 39% less likely to receive an angioplasty stent (adjusted odds ratio 0.61, 95% confidence intervals 0.39-0.96) and 66% less likely to receive grafts (adjusted OR 0.34, 95% CIs 0.13-0.93). Women diagnosed with NSTEMI were 44% less likely to receive grafts (adjusted OR 0.56, 95% CIs 0.37-0.83). Younger women aged 35-49 years were less likely to receive an angioplasty stent, and older women >50 years were less likely to receive grafts. CONCLUSIONS: Adherence to guideline based treatment will help to ensure knowledge translation from guideline to practice. Further research investigating symptom presentation, use of non-invasive tests and medical management of ACS by gender may further explain gender difference for coronary interventions.

Gender differences in presentation, coronary intervention, and outcomes of 28,985 acute coronary syndrome patients in Victoria, Australia

BACKGROUND: Differences in demographics, presenting characteristics, and treatment of heart disease in women may contribute to adverse outcomes. The purpose of this paper was to describe gender differences in the epidemiology, treatment, and outcomes of all admissions for acute coronary syndrome (ACS) in Victoria that occurred between June 2007 and July 2009. METHODS: We undertook a retrospective cohort study of all patients admitted to Victorian hospitals with a first time diagnosis of ACS. Use of angiograms, percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), and adverse outcomes (death and/or unplanned readmission) were compared by gender and hierarchical logistic regression models were used to account for confounding variables. RESULTS: Of a total of 28,985 ACS patients, 10,455 (36%) were women. Compared with men, women were older (aged ≥75 years: 54% vs 31%; p < .001), more likely to present with multiple comorbidities (>1 comorbidity: 53% vs 46%; p < .001), and more likely to be diagnosed with non-ST-segment elevation ACS (86% vs 80%; p < .001). Women were less likely to receive coronary interventions (angiogram: adjusted odds ratio [aOR], 0.71; 95% CI, 0.66-0.75; PCI: aOR, 0.73; 95% CI, 0.66-0.80; CABG: aOR, 0.58; 95% CI, 0.53-0.64). Adverse outcomes were similar in women and men after accounting for confounding variables. CONCLUSIONS: Our results show that women in Victoria were less likely to receive coronary interventions after an admission for ACS. Clinicians should be wary of inherent gender bias in decisions to refer patients for angiography.

Efficacy and safety of thrombin-receptor antagonist (atopaxar and vorapaxar) in patients with acute coronary syndrome or coronary artery disease-a meta-analysis of randomized controlled trials

Background: Meta-analysis for the efficacy and safety data of thrombin-receptor antagonist (TRA) based on patients with acute coronary syndrome (ACS) or coronary artery disease (CAD) and indirect comparisons between TRAs were not available. Objectives: We intended to synthesize the primary end points based on different patient populations (ACS or CAD) as well as perform indirect comparison between two newly invented antiplatelet agents atopaxar and vorapaxar. Methods: A literature search was performed in MEDLINE, Embase, and Cochrane Library. Incidences of major adverse cardiovascular events (MACEs) and bleeding events according to thrombolysis in myocardial infarction were selected as primary outcomes, whereas adverse effects were considered as secondary outcomes. Corresponding results were synthesized using Revman 5.1 according to ACS or CAD cohorts. Results: Among the seven included randomized controlled trials, the efficacy end points in the TRA treatment group were favorable compared with placebo. Specifically, the odds ratio (OR) of MACEs was 0.80 (95% confidence interval [CI] 0.52-1.22) for patients with ACS and 0.74 (95% CI 0.53-1.05) for the cohort with CAD. The events of bleeding were unanimously superior in the placebo arm for both cohorts. The indirect comparison showed a superior trend in favor of atopaxar over vorapaxar in occurrences of MACEs (OR 0.93; 95% CI 0.38-1.32), myocardial infarction (OR 0.52; 95% CI 0.13-0.95), and cardiovascular death (OR 0.82; 95% CI 0.12-4.24) and caused less incidence of bleeding. Conclusions: Besides being more effective than placebo in improving the incidence of MACEs but with a higher risk of bleeding, TRAs may exert different effects in patients with ACS and CAD. Indirect comparisons also suggested that atopaxar might be better than vorapaxar in lowering the incidence of MACEs, myocardial infarction, and cardiovascular death and at the same time with lower risks of bleeding.