First and recurrent ischaemic heart disease events continue to decline in New Zealand, 2005-2015

Sex differences in outcomes after acute coronary syndrome vary with age: a New Zealand national study

AIMS

This study investigated age-specific sex differences in short- and long-term clinical outcomes following hospitalization for a first-time acute coronary syndrome (ACS) in New Zealand (NZ).

METHODS AND RESULTS

Using linked national health datasets, people admitted to hospital for a first-time ACS between January 2010 and December 2016 were included. Analyses were stratified by sex and 10-year age groups. Logistic and Cox regression were used to assess in-hospital death and from discharge the primary outcome of time to first cardiovascular (CV) readmission or death and other secondary outcomes at 30 days and 2 years. Among 63 245 people (mean age 69 years, 40% women), women were older than men at the time of the ACS admission (mean age 73 vs. 66 years), with a higher comorbidity burden. Overall compared with men, women experienced higher rates of unadjusted in-hospital death (10% vs. 7%), 30-day (16% vs. 12%) and 2-year (44% vs. 34%) death, or CV readmission (all P < 0.001). Age group-specific analyses showed sex differences in outcomes varied with age, with younger women (<65 years) at higher risk than men and older women (≥85 years) at lower risk than men: unadjusted hazard ratio of 2-year death or CV readmission for women aged 18-44 years = 1.51 [95% confidence interval (CI) 1.21-1.84] and aged ≥85 years = 0.88 (95% CI 0.83-0.93). The increased risk for younger women was no longer significant after multivariable adjustment whereas the increased risk for older men remained.

CONCLUSION

Men and women admitted with first-time ACS have differing age and comorbidity profiles, resulting in contrasting age-specific sex differences in the risk of adverse outcomes between the youngest and oldest age groups.

Breaking Point Toward Decreasing Prevalence of Myocardial Infarction Owing to Relative Stronger Decrease in Incidence Than Increase in Survival Rate (A Danish Cohort Study [1994-2016])

The aim of this study was to examine whether myocardial infarction (MI) incidence rate continues to decrease and to determine whether the relative magnitude of a potentially decreasing incidence rate has surpassed increasing survival, demasking a breaking point in trends of MI prevalence proportion. This was a nationwide population-based cohort study using medical registries covering all hospitals in Denmark (1994 to 2016). We identified 193,870 persons with a first-time hospitalization for MI. Age-standardized incidence rates (per 100,000 persons) decreased from 154 (95% confidence interval [CI] 149 to 159) in 1994 to 90 (95% CI 86 to 93) in 2016 for females, and from 335 (95% CI 326 to 344) in 1994 to 205 (95% CI 199 to 211) in 2016 for males. Age-standardized prevalence proportion increased overall from 1994 to 2004 with a subsequent plateau. From 2006 to 2016, age-standardized prevalence proportion decreased by 0.09% (95% CI 0.07% to 0.11%) for females (from 1.07% to 0.98%) and by 0.20% (95% CI 0.17% to 0.23%) for males (from 2.85% to 2.65%). The age-standardized prevalence proportion decreased solely among persons aged 55 to 84 years. It remained stable among persons aged <55 years and increased among persons aged ≥85 years until 2012 with subsequent stable trends. We conclude that the continuous decreasing age-standardized incidence rate of MI over decades has, although with increasing survival, led to an overall breaking point toward a decreasing age-standardized prevalence proportion of MI since 2006.

Cardiovascular risk prediction in type 2 diabetes before and after widespread screening: a derivation and validation study

BACKGROUND

Until recently, most patients with diabetes worldwide have been diagnosed when symptomatic and have high cardiovascular risk, meaning most should be prescribed cardiovascular preventive medications. However, in New Zealand, a world-first national programme led to approximately 90% of eligible adults being screened for diabetes by 2016, up from 50% in 2012, identifying many asymptomatic patients with recent-onset diabetes. We hypothesised that cardiovascular risk prediction equations derived before widespread screening would now significantly overestimate risk in screen-detected patients.

METHODS

New Zealanders aged 30-74 years with type 2 diabetes and without known cardiovascular disease, heart failure, or substantial renal impairment were identified from the 400 000-person PREDICT primary care cohort study between Oct 27, 2004, and Dec 30, 2016, covering the period before and after widespread screening. Sex-specific equations estimating 5-year risk of cardiovascular disease were developed using Cox regression models, with 18 prespecified predictors, including diabetes-related and renal function measures. Equation performance was compared with an equivalent equation derived in the New Zealand Diabetes Cohort Study (NZDCS), which recruited between 2000 and 2006, before widespread screening.

FINDINGS

46 652 participants were included in the PREDICT-1° Diabetes subcohort, of whom 4114 experienced first cardiovascular events during follow-up (median 5·2 years, IQR 3·3-7·4). 14 829 (31·8%) were not taking oral hypoglycaemic medications or insulin at baseline. Median 5-year cardiovascular risk estimated by the new equations was 4·0% (IQR 2·3-6·8) in women and 7·1% (4·5-11·2) in men. The older NZDCS equation overestimated median cardiovascular risk by three times in women (median 14·2% [9·7-20·0]) and two times in men (17·1% [4·5-20·0]). Model and discrimination performance measures for PREDICT-1° Diabetse equations were also significantly better than for the NZDCS equation (eg, for women: R²=32% [95% CI 29-34], Harrell's C=0·73 [0·72-0·74], Royston's D=1·410 [1·330-1·490] vs R²=24% [21-26], C=0·69 [0·67-0·70], and D=1·147 [1·107-1·187]).

INTERPRETATION

International treatment guidelines still consider most people with diabetes to be at high cardiovascular risk; however, we show that recent widespread diabetes screening has radically changed the cardiovascular risk profile of people with diabetes in New Zealand. Many of these patients have normal renal function, are not dispensed glucose-lowering medications, and have low cardiovascular risk. These findings have clear international implications as increased diabetes screening is inevitable due to increasing obesity, simpler screening tests, and the introduction of new-generation glucose-lowering medications that prevent cardiovascular events. Cardiovascular risk prediction equations derived from contemporary diabetes populations, with multiple diabetes-related and renal function predictors, will be required to better differentiate between low-risk and high-risk patients in this increasingly heterogeneous population and to inform appropriate non-pharmacological management and cost-effective targeting of expensive new medications.

FUNDING

Health Research Council of New Zealand, Heart Foundation of New Zealand, and Healthier Lives National Science Challenge.

Trends in Ischaemic Heart Disease in Australia, 2001-2015: A Comparison of Urban and Rural Populations

OBJECTIVE

Ischaemic heart disease (IHD) is a major source of disease burden worldwide. Recent trends show incidence is declining but it is unclear whether the trends are similar in urban and rural populations. This study examines the trends of IHD events (i.e. hospitalisations and deaths) in New South Wales, Australia by rurality.

METHODS

This was a retrospective analysis of linked administrative data for hospitalisation and death records across NSW between 2001 and 2015. Participants were NSW residents aged 15-105 years who died or were hospitalised with a principal diagnosis of IHD. The main outcome measures were annual age-standardised mortality and hospitalisations for IHD by calendar year and rurality.

RESULTS

Between 2001 and 2015, age-standardised annual IHD hospitalisations declined in urban areas from 587 to 260 and in rural areas from 766 to 395 per 100,000 people. The annual decline in hospitalisations was greater in urban than rural areas, with Annual Percentage Change (APC) of -5.6% (95% CI, -6.1%, -5.0%) and -4.5% (95% CI, -5.0%, -4.0%), respectively (p=0.012). Ischaemic heart disease mortality declined at a similar rate in urban and rural regions (APC -7.6% and -6.7% per annum, p=0.28). Absolute inequalities in IHD deaths persisted until 2015 when there were 49 (urban) and 70 (rural) IHD deaths per 100,000 people.

CONCLUSIONS

Ischaemic heart disease hospitalisations and mortality have declined considerably between 2001 and 2015 in both rural and urban areas, yet inequalities persist, suggesting more intensive preventive efforts are required to further reduce the burden of IHD in rural populations.

Both incidence and prevalence of ischaemic heart disease are declining in parallel: a national data-linkage study in New Zealand (ANZACS-QI 52)

AIMS

To examine trends in ischaemic heart disease (IHD) incidence and prevalence in New Zealand from 2005 to 2016, using comprehensive linked national hospitalization and mortality data as proxy measures of all significant events.

METHODS AND RESULTS

Incident and prevalent cases of IHD in people aged ≥25 years were identified using individual patient-linkage of routinely collected ICD-10-coded hospitalization and mortality data. Incidence rates and prevalence proportions were calculated by sex and age group and then age-standardized to the 2016 New Zealand population. Ischaemic heart disease incidence and prevalence declined in men and women in all age groups. The average annual rate of decline in age-standardized IHD incidence was 3.3% for women and 2.7% for men, and the rate of decline in age-standardized IHD prevalence was 3.2% for women and 2.2% for men. Despite a 17% increase in the New Zealand population aged 25 years and over during the study period, the total number of people living with IHD also decreased, particularly in those aged 65 years and older.

CONCLUSION

In contrast to observations from other countries, where IHD incidence but not IHD prevalence has been falling, declining IHD incidence in New Zealand in recent decades is now mirrored by declining IHD prevalence.

Trends in cardiovascular outcomes after acute coronary syndrome in New Zealand 2006-2016

OBJECTIVES

Characterisation of trends in acute coronary syndrome (ACS) outcomes are critical to informing clinical practice and quality improvement, but there are few recent population studies for ACS. We reviewed the recent trends in the outcomes of ACS in New Zealand (NZ).

METHODS

All patients with ACS admitted to NZ public hospitals in 2006-2016 were identified from hospital discharge records, and their first ACS hospitalisations per year extracted for analysis. Thirty-day and 1-year death, myocardial infarction, stroke, heart failure and bleeding rates were calculated for each calendar year. Trends in outcome rates were assessed using generalised linear mixed models.

RESULTS

Total annual ACS hospitalisations decreased from 685 to 424 per 100 000. Using first patient hospitalisations per year (n=1 55 060), we found significant annual declines in all major outcomes except for non-cardiovascular deaths. All-cause mortality fell from 10.5% to 9.1% at 30 days (adjusted OR 0.985 per year change, p<0.001) and from 21.8% to 18.7% at 1 year (OR=0.994, p=0.016). This was related to significant decreases in cardiovascular death at both time points (OR=0.982 and 0.987, respectively, p<0.001), outweighing a slight increase in non-cardiovascular death at 1 year (OR=1.009, p=0.014). One-year rates of myocardial infarction, heart failure, stroke and bleeding rates all decreased significantly over time.

CONCLUSION

ACS outcomes including all-cause mortality, cardiovascular death, myocardial infarction, stroke, heart failure and bleeding at 30 days and 1 year improved over the last decade in NZ, reflecting successful implementation and advances in prevention, medical and invasive management in ACS over time.

Long-term trends in the incidence, treatment, hospital fatality and subsequent mortality from acute myocardial infarction in the Czech Republic

AIMS

Studies on the incidence, acute and subsequent mortality from myocardial infarction are limited mostly to selected clinical cohorts and populations and cover relatively short periods. Our aim was to describe and analyse long-term trends on a national scale.

METHODS

Acute myocardial infarction (AMI) was defined by the International Classification of Diseases (ICD)10; codes I21 and I22. Our natiowide 1994-2016 data on AMI mortality were obtained from the official mortality statistics (Czech Bureau of Statistics), data on morbidity (hospitalizations) from the National Register of Hospitalizations (Institute for Health Information and Statistics). For further analyses, data from the Czech EUROASPIRE I-V and Czech IMPACT studies were used.

RESULTS

Over the 1994-2016 period the total number of AMI cases per year decreased from 34,084 to 19,015, that of patients hospitalized for AMI from 22,373 to 15,419, the total number of deaths due to AMI from 14,834 to 4,673, in those treated because of AMI from 3,794 to 1,137, and hospital fatality in patients treated for AMI decreased from 17% to 7.5%. Over the years 1997-2016, the one-year all-cause mortality rate after AMI declined from 25.1 to 17.9%, cardiovascular (CV) mortality from 22.3 to 14.2%, five-year all-cause mortality from 41.7 to 34%, and CV mortality from 34.1 to 23.6%.

CONCLUSION

The Czech Republic has witnessed a pronounced decrease in AMI incidence and fatality and, consequently, long-term mortality. The decreasing incidence and improving course of AMI are due to progress in primary prevention, in acute coronary care and interventional cardiology, and in secondary coronary heart disease (CHD) prevention.

Contrasting Trends in Acute Coronary Syndrome Hospitalisation and Coronary Revascularisation in New Zealand 2006-2016: A National Data Linkage Study (ANZACS-QI 27)

BACKGROUND

Evaluating trends in acute coronary syndrome (ACS) and invasive coronary procedures, including coronary angiography, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) can identify areas for improvement in clinical care and inform future health planning. This national data-linkage study reports trends in ACS hospitalisations and procedure rates in New Zealand between 2006 and 2016.

METHODS

All adult ACS hospitalisations and associated angiography and revascularisation procedures were identified from hospital discharge codes. Crude and age-standardised ACS incidence and procedure rates were calculated for each calendar year.

RESULTS

Between 2006 and 2016 there were 188,264 ACS admissions. During this time, there was a steady decline in hospitalisation rates, from 685 to 424 per 100,000 per year. This decline was observed in both sexes and in all age groups. There were also significant increases in coronary angiography and revascularisation rates, from 29.8% to 54.3% and 20.6% to 37.3%, respectively, between 2006 and 2016. The rate of revascularisation by PCI increased from 16.0% to 31.0%, a greater increase than revascularisation by CABG, which increased from 4.6% to 6.5%. Increases in procedures were observed in all age groups and both sexes. The proportions of coronary angiograms that resulted in revascularisation each year consistently ranged from 67 to 70% throughout the period.

CONCLUSIONS

Acute coronary syndrome hospitalisation rates in New Zealand decreased by nearly 40% between 2006 and 2016, while the use of coronary angiography and revascularisation after ACS nearly doubled. The similar proportions of angiograms that resulted in revascularisation each year suggests that, despite the doubling of angiograms over the 10-year study period, they are not over-utilised.

World Health Organization cardiovascular disease risk charts: revised models to estimate risk in 21 global regions

BACKGROUND

To help adapt cardiovascular disease risk prediction approaches to low-income and middle-income countries, WHO has convened an effort to develop, evaluate, and illustrate revised risk models. Here, we report the derivation, validation, and illustration of the revised WHO cardiovascular disease risk prediction charts that have been adapted to the circumstances of 21 global regions.

METHODS

In this model revision initiative, we derived 10-year risk prediction models for fatal and non-fatal cardiovascular disease (ie, myocardial infarction and stroke) using individual participant data from the Emerging Risk Factors Collaboration. Models included information on age, smoking status, systolic blood pressure, history of diabetes, and total cholesterol. For derivation, we included participants aged 40-80 years without a known baseline history of cardiovascular disease, who were followed up until the first myocardial infarction, fatal coronary heart disease, or stroke event. We recalibrated models using age-specific and sex-specific incidences and risk factor values available from 21 global regions. For external validation, we analysed individual participant data from studies distinct from those used in model derivation. We illustrated models by analysing data on a further 123 743 individuals from surveys in 79 countries collected with the WHO STEPwise Approach to Surveillance.

FINDINGS

Our risk model derivation involved 376 177 individuals from 85 cohorts, and 19 333 incident cardiovascular events recorded during 10 years of follow-up. The derived risk prediction models discriminated well in external validation cohorts (19 cohorts, 1 096 061 individuals, 25 950 cardiovascular disease events), with Harrell's C indices ranging from 0·685 (95% CI 0·629-0·741) to 0·833 (0·783-0·882). For a given risk factor profile, we found substantial variation across global regions in the estimated 10-year predicted risk. For example, estimated cardiovascular disease risk for a 60-year-old male smoker without diabetes and with systolic blood pressure of 140 mm Hg and total cholesterol of 5 mmol/L ranged from 11% in Andean Latin America to 30% in central Asia. When applied to data from 79 countries (mostly low-income and middle-income countries), the proportion of individuals aged 40-64 years estimated to be at greater than 20% risk ranged from less than 1% in Uganda to more than 16% in Egypt.

INTERPRETATION

We have derived, calibrated, and validated new WHO risk prediction models to estimate cardiovascular disease risk in 21 Global Burden of Disease regions. The widespread use of these models could enhance the accuracy, practicability, and sustainability of efforts to reduce the burden of cardiovascular disease worldwide.

FUNDING

World Health Organization, British Heart Foundation (BHF), BHF Cambridge Centre for Research Excellence, UK Medical Research Council, and National Institute for Health Research.

The 21st Century Echocardiography Laboratory in Australia and New Zealand: Rapid Evolution of Training and Workforce, Practice and Technology

Echocardiography is a common and increasingly used noninvasive imaging tool in medicine. In this paper, we imagine the echocardiography laboratory of the future and consider the challenges we face currently, and may face in the future, and how these might be overcome; challenges such as training enough sonographers to meet the increasing demands of the ageing population living with chronic cardiovascular disease and the need for surveillance in other clinical scenarios. We consider the changing qualification framework and the requirements for accreditation and registration in Australia and New Zealand and the potential for migrant sonographers to meet some of the increasing demand. Advanced scopes of practice are likely to be a feature of the future workforce and we consider some of the ways these may evolve. Lastly, we consider how the evolving clinical landscape and technology may change the way echocardiography is delivered.

Comparative trends in coronary heart disease subgroup hospitalisation rates in England and Australia

Background

Population-based coronary heart disease (CHD) studies have focused on myocardial infarction (MI) with limited data on trends across the spectrum of CHD. We investigated trends in hospitalisation rates for acute and chronic CHD subgroups in England and Australia from 1996 to 2013.

Methods

CHD hospitalisations for individuals aged 35–84 years were identified from electronic hospital data from 1996 to 2013 for England and Australia and from the Oxford Region and Western Australia. CHD subgroups identified were acute coronary syndromes (ACS) (MI and unstable angina) and chronic CHD (stable angina and ‘other CHD’). We calculated age-standardised and age-specific rates and estimated annual changes (95% CI) from age-adjusted Poisson regression.

Results

From 1996 to 2013, there were 4.9 million CHD hospitalisations in England and 2.6 million in Australia (67% men). From 1996 to 2003, there was between-country variation in the direction of trends in ACS and chronic CHD hospitalisation rates (p<0.001). During 2004–2013, reductions in ACS hospitalisation rates were greater than for chronic CHD hospitalisation rates in both countries, with the largest subgroup declines in unstable angina (England: men: −7.1 %/year, 95% CI −7.2 to –7.0; women: −7.5 %/year, 95% CI −7.7 to –7.3; Australia: men: −8.5 %/year, 95% CI −8.6 to –8.4; women: −8.6 %/year, 95% CI −8.8 to –8.4). Other CHD rates increased in individuals aged 75–84 years in both countries. Chronic CHD comprised half of all CHD admissions, with the majority involving angiography or percutaneous coronary intervention.

Conclusions

Since 2004, rates of all CHD subgroups have fallen, with greater declines in acute than chronic presentations. The slower declines and high proportion of chronic CHD admissions undergoing coronary procedures requires greater focus.

Performance of a Framingham cardiovascular risk model among Indians and Europeans in New Zealand and the role of body mass index and social deprivation

Objectives

To evaluate a Framingham 5-year cardiovascular disease (CVD) risk score in Indians and Europeans in New Zealand, and determine whether body mass index (BMI) and socioeconomic deprivation were independent predictors of CVD risk.

Methods

We included Indians and Europeans, aged 30–74 years without prior CVD undergoing risk assessment in New Zealand primary care during 2002–2015 (n=256 446). Risk profiles included standard Framingham predictors (age, sex, systolic blood pressure, total cholesterol/high-density lipoprotein ratio, smoking and diabetes) and were linked with national CVD hospitalisations and mortality datasets. Discrimination was measured by the area under the receiver operating characteristics curve (AUC) and calibration examined graphically. We used Cox regression to study the impact of BMI and deprivation on the risk of CVD with and without adjustment for the Framingham score.

Results

During follow-up, 8105 and 1156 CVD events occurred in Europeans and Indians, respectively. Higher AUCs of 0.76 were found in Indian men (95% CI 0.74 to 0.78) and women (95% CI 0.73 to 0.78) compared with 0.74 (95% CI 0.73 to 0.74) in European men and 0.72 (95% CI 0.71 to 0.73) in European women. Framingham was best calibrated in Indian men, and overestimated risk in Indian women and in Europeans. BMI and deprivation were positively associated with CVD, also after adjustment for the Framingham risk score, although the BMI association was attenuated.

Conclusions

The Framingham risk model performed reasonably well in Indian men, but overestimated risk in Indian women and in Europeans. BMI and socioeconomic deprivation could be useful predictors in addition to a Framingham score.

Improved outcomes in patients with ST-elevation myocardial infarction during the last 20 years are related to implementation of evidence-based treatments: experiences from the SWEDEHEART registry 1995-2014

Aims

Impact of changes of treatments on outcomes in ST-elevation myocardial infarction (STEMI) patients in real-life health care has not been documented.

Methods and results

All STEMI cases (n = 105.674) registered in the nation-wide SWEDEHEART registry between 1995 and 2014 were included and followed for fatal and non-fatal outcomes for up to 20 years. Most changes in treatment and outcomes occurred from 1994 to 2008. Evidence-based treatments increased: reperfusion from 66.2 to 81.7%; primary percutaneous coronary intervention: 4.5 to 78.0%; dual antiplatelet therapy from 0 to 89.6%; statin: 14.1 to 93.6%; beta-blocker: 78.2 to 91.0%, and angiotensin-converting-enzyme/angiotensin-2-receptor inhibitors: 40.8 to 85.2% (P-value for-trend <0.001 for all). One-year mortality decreased from 22.1 to 14.1%. Standardized incidence ratio compared with the general population decreased from 5.54 to 3.74 (P < 0.001). Cardiovascular (CV) death decreased from 20.1 to 11.1%, myocardial infarction (MI) from 11.5 to 5.8%; stroke from 2.9 to 2.1%; heart failure from 7.1 to 6.2%. After standardization for differences in demography and baseline characteristics, the change of 1-year CV-death or MI corresponded to a linear trend of 0.915 (95% confidence interval: 0.906–0.923) per 2-year period which no longer was significant, 0.997 (0.984–1.009), after adjustment for changes in treatment. The changes in treatment and outcomes were most pronounced from 1994 to 2008.

Conclusion

Gradual implementation of new and established evidence-based treatments in STEMI patients during the last 20 years has been associated with prolonged survival and lower risk of recurrent ischaemic events, although a plateauing is seen since around 2008.