Is a novel diagnostic pathway for cardiology outpatient clinics in Singapore lower cost than existing practice: a cost modelling study.

OBJECTIVE: To evaluate the potential for change to costs from a decision to adopt a novel diagnostic pathway for referrals to cardiology outpatients with symptoms of chest pain. DESIGN: Costs modelling study using existing observational data, with a cost year of 2018. SETTING: Specialist Heart Centre in Singapore. PARTICIPANTS: All new referrals (n=10 622) to the outpatient clinics for investigation between January 2017 and December 2017. INTERVENTIONS: Two competing testing regimes are compared in a decision tree model. Current practice includes classification of patients by their risk and the use of treadmill tests, calcium scores, functional testing and CT angiogram. New practice offers a fundamental difference in use of diagnostics for patients, with some offered angiogram directly and for low-risk patients a calcium score is used to refine risk stratification. OUTCOME MEASURES: The expected cost difference between testing alternatives. RESULTS: The expected cost saving from 'New Practice' as compared with 'Current Practice' is $S764 per patient. There is a 50% probability the savings per patient range between $S764 and $S824 and a 90% probability they are between $S616 and $S912. The expected savings to Singapore national health services are $S26.8 million annually, with a range of $S16.2 to $S41.1 million. CONCLUSIONS: We find some evidence that using a coronary calcium score, which can be performed with a fraction of the time and cost of a CT coronary angiogram, saves costs to health services.

Ethnic Differences and Trends in ST-Segment Elevation Myocardial Infarction Incidence and Mortality in a Multi-Ethnic Population.

INTRODUCTION: This study aimed to compare the incidence and mortality of ST-segment elevation myocardial infarction (STEMI) across the 3 main ethnic groups in Singapore, determine if there is any improvement in trends over the years and postulate the reasons underlying the ethnic disparity. MATERIALS AND METHODS: This study consisted of 16,983 consecutive STEMI patients who sought treatment from all public hospitals in Singapore from 2007 to 2014. RESULTS: Compared to the Chinese (58 per 100,000 population in 2014), higher STEMI incidence rate was consistently observed in the Malays (114 per 100,000 population) and Indians (126 per 100,000 population). While the incidence rate for the Chinese and Indians remained relatively stable over the years, the incidence rate for the Malays rose slightly. Relative to the Indians (30-day and 1-year all-cause mortality at 9% and 13%, respectively, in 2014), higher 30-day and 1-year all-cause mortality rates were observed in the Chinese (15% and 21%) and Malays (13% and 18%). Besides the Malays having higher adjusted 1-year all-cause mortality, all other ethnic disparities in 30-day and 1-year mortality risk were attenuated after adjusting for demographics, comorbidities and primary percutaneous coronary intervention. CONCLUSION: It is important to continuously evaluate the effectiveness of existing programmes and practices as the aetiology of STEMI evolves with time, and to strike a balance between prevention and management efforts as well as between improving the outcome of "poorer" and "better" STEMI survivors with finite resources.

Influence of Ethnicity, Age, and Time on Sex Disparities in Long-Term Cause-Specific Mortality After Acute Myocardial Infarction.

BACKGROUND: We examined the influence of sex, ethnicity, and time on competing cardiovascular and noncardiovascular causes of death following acute myocardial infarction in a multiethnic Asian cohort. METHODS AND RESULTS: For 12 years, we followed a prospective nationwide cohort of 15 151 patients (aged 22-101 years, median age 63 years; 72.3% male; 66.7% Chinese, 19.8% Malay, 13.5% Indian) who were hospitalized for acute myocardial infarction between 2000 and 2005. There were 6463 deaths (4534 cardiovascular, 1929 noncardiovascular). Compared with men, women had a higher risk of cardiovascular death (age-adjusted hazard ratio [HR] 1.3, 95% CI 1.2-1.4) but a similar risk of noncardiovascular death (HR 0.9, 95% CI 0.8-1.0). Sex differences in cardiovascular death varied by ethnicity, age, and time. Compared with Chinese women, Malay women had the greatest increased hazard of cardiovascular death (HR 1.4, 95% CI 1.2-1.6) and a marked imbalance in death due to heart failure or cardiomyopathy (HR 3.4 [95% CI 1.9-6.0] versus HR 1.5 [95% CI 0.6-3.6] for Indian women). Compared with same-age Malay men, Malay women aged 22 to 49 years had a 2.5-fold (95% CI 1.6-3.8) increased hazard of cardiovascular death. Sex disparities in cardiovascular death tapered over time, least among Chinese patients and most among Indian patients; the HR comparing cardiovascular death of Indian women and men decreased from 1.9 (95% CI 1.5-2.4) at 30 days to 0.9 (95% CI 0.5-1.6) at 10 years. CONCLUSION: Age, ethnicity, and time strongly influence the association between sex and specific cardiovascular causes of mortality, suggesting that health care policy to reduce sex disparities in acute myocardial infarction outcomes must consider the complex interplay of these 3 major modifying factors.

Lifetime cost-effectiveness analysis of ticagrelor in patients with acute coronary syndromes based on the PLATO trial: a Singapore healthcare perspective.

INTRODUCTION: Ticagrelor is a novel antiplatelet drug developed to reduce atherothrombosis. The PLATO trial compared ticagrelor and aspirin to clopidogrel and aspirin in patients with acute coronary syndromes (ACS). Ticagrelor was found to be superior in the primary composite endpoint of cardiovascular death, myocardial infarction or stroke, without increasing major bleeding events. The current study estimates the lifetime cost-effectiveness of ticagrelor relative to generic clopidogrel from a Singapore public healthcare perspective. METHODS: This study used a two-part cost-effectiveness model. The first part was a 12-month decision tree (using PLATO trial data) to estimate the rates of major cardiovascular events, healthcare costs and health-related quality of life. The second part was a Markov model estimating lifetime quality-adjusted survival and costs conditional on events during the initial 12 months. Daily drug costs applied were SGD 1.05 (generic clopidogrel) and SGD 6.00 (ticagrelor). Cost per quality-adjusted life years (QALY) was estimated from a Singapore public healthcare perspective using life tables and short-term costs from Singapore, and long-term costs from South Korea. Deterministic and probabilistic sensitivity analyses were performed. RESULTS: Ticagrelor was associated with a lifetime QALY gain of 0.13, primarily driven by lower mortality. The resulting incremental cost per QALY gained was SGD 10,136.00. Probabilistic sensitivity analysis indicated that ticagrelor had a > 99% probability of being cost-effective, given the lower recommended WHO willingness-to-pay threshold of one GDP/capita per QALY. CONCLUSION: Based on PLATO trial data, one-year treatment with ticagrelor versus generic clopidogrel in patients with ACS, relative to WHO reference standards, is cost-effective from a Singapore public healthcare perspective.

Public perceptions, knowledge and awareness of cholesterol management in Singapore: a prospective pilot study.

INTRODUCTION: Hyperlipidaemia is a major risk factor for coronary artery disease (CAD). Its effective treatment has been shown to reduce the incidence of cardiovascular events, both in secondary and primary prevention. An essential component of risk factor management at the community level is public awareness and knowledge of treatment benefits. However, this data is limited in Singapore. METHODS: A cross-sectional survey questionnaire of public perception and knowledge on cholesterol treatment among adult Singaporeans aged 30-69 years was commissioned by the Singapore Heart Foundation and conducted by a professional market survey company. Regional quota sampling was performed to ensure that the sample was representative of the Singapore population. This was followed by random sampling of households and respondents. RESULTS: Of the 365 respondents, 40.9% were male, 70.3% were Chinese, 18.8% Malay and 10.9% Indian. The mean age was 47.5 years. Although 81.9% of respondents had medical check-ups involving blood tests, only 11.0% knew their actual cholesterol levels. A third of the respondents saw herbal medicine as healthier and safer than Western medication. More than 80% of respondents believed that diet and exercise were equally effective at lowering cholesterol as medication. About half of the respondents associated long-term use of statins with damage to the liver and kidney, while a third associated chronic statin use with the development of cancer. CONCLUSION: There are gaps in the level of public awareness and understanding of cholesterol treatment in Singapore. Common misconceptions should be addressed, as they could potentially impair effective management or treatment compliance.

Risk assessment models in acute coronary syndromes and their applicability in Singapore.

Risk prediction models are critical in managing patients with acute coronary syndromes (ACS) as they identify high-risk patients who benefit the most from targeted care. We discuss the process of developing and validating a risk prediction model as well as highlight the more commonly used models in clinical practice currently. Finally we conclude by outlining the importance of creating a risk prediction model based on a Singapore population of ACS patients so as to further improve patient, hospital and research outcomes.

Pattern and outcome of subsidised referrals to cardiology specialist outpatient clinics.

INTRODUCTION: Increasing demand for public healthcare and access to specialist care has become a major concern. Characterising the referral pattern to a national centre's cardiology specialist outpatient clinics (SOCs) and the diagnostic outcomes may be useful in formulating referral guidelines to contain rising demand. MATERIALS AND METHODS: A prospective observational followup study was conducted of all consecutive new patient referrals to the cardiology SOCs of the National Heart Centre over a 1-month period. The records of these 1224 patients were reviewed following their first visit and again after 3 months of evaluation and investigation. Patients' demographics, referral sources, indications of referral, risk factors, provisional and final diagnoses were collected. Referrals from the top 2 volume sources (government polyclinics and hospital Emergency Department) accounted for 600 referrals. These subsidised referrals formed the study group for analysis. RESULTS: The mean age of referred patients was 56 +/- 15.2 years, with equal proportion of males and females. Most patients had known cardiac risk factors of hypertension (53.2%) and hyperlipidaemia (42.3%). Only 23% of referrals had significant cardiac abnormalities. Referrals for typical chest pain derived the highest yield whereas referrals for atypical chest pain, non-cardiac chest pain derived the lowest yield. Referrals for asymptomatic electrocardiogram (ECG) changes (except for atrial flutter/fibrillation) did not yield cardiac abnormalities. Multivariate analysis of chest pain referrals showed typical chest pain and hyperlipidaemia to be statistically significant predictors for coronary artery disease. CONCLUSION: Referrals to cardiology outpatient specialist clinics should be based on the presence of patient symptoms, particularly that of typical chest pain. In asymptomatic patients, routine ECG screening did not appear to yield significant cardiac abnormalities.

Improving access to outpatient cardiac care at the national heart centre--a partnership between specialists and primary care.

Ensuring timely access to specialist care is an important indicator of the quality of a health service. Demand for cardiology outpatient appointments has grown considerably in the last decade, leading to increased waiting time for cardiology appointments at public hospitals. This paper examines the effectiveness of past and ongoing strategies initiated by the National Heart Centre, many of which were in collaboration with SingHealth Polyclinics, documents the lessons learnt, and provides a framework for approaching this problem. Instead of a simplistic approach where institutions react to long waiting times by growing capacity to meet demand, this paper emphasises the need to focus on the final intended outcome (timely diagnosis and treatment) rather than on a single performance indicator, such as waiting time. A broad systems approach at the national level is advocated, rather than piecemeal, uncoordinated actions by individual hospitals.