Performance of cardiovascular disease risk prediction equations in more than 14 000 survivors of cancer in New Zealand primary care: a validation study.

BACKGROUND: People with cancer have an increased risk of cardiovascular disease. Risk prediction equations developed in New Zealand accurately predict 5-year cardiovascular disease risk in a general primary care population in the country. We assessed the performance of these equations for survivors of cancer in New Zealand. METHODS: For this validation study, patients aged 30-74 years from the PREDICT open cohort study, which was used to develop the New Zealand cardiovascular disease risk prediction equations, were included in the analysis if they had a primary diagnosis of invasive cancer at least 2 years before the date of the first cardiovascular disease risk assessment. The risk prediction equations are sex-specific and include the following predictors: age, ethnicity, socioeconomic deprivation index, family history of cardiovascular disease, smoking status, history of atrial fibrillation and diabetes, systolic blood pressure, total cholesterol to HDL cholesterol ratio, and preventive pharmacotherapy (blood-pressure-lowering, lipid-lowering, and antithrombotic drugs). Calibration was assessed by comparing the mean predicted 5-year cardiovascular disease risk, estimated using the risk prediction equations, with the observed risk across deciles of risk, for men and women, and according to the three clinical 5-year cardiovascular disease risk groups in New Zealand guidelines (<5%, 5% to <15%, and ≥15%). Discrimination was assessed by Harrell's C statistic. FINDINGS: 14 263 patients were included in the study. The mean age was 61 years (SD 9) for men and 60 years (SD 8) for women, with a median follow-up of 5·8 years for men and 5·7 years for women. The observed cardiovascular disease risk was underpredicted by a maximum of 2·5% in male and 3·2% in female decile groups. When patients were grouped according to clinical risk groups, observed cardiovascular disease risk was underpredicted by less than 2% in the lower risk groups and overpredicted by 2·2% for men and 3·3% for women in the highest risk group. Harrell's C statistics were 0·67 (SE 0·01) for men and 0·73 (0·01) for women. INTERPRETATION: The New Zealand cardiovascular disease risk prediction equations reasonably predicted the observed 5-year cardiovascular disease risk in survivors of cancer in the country, in whom risk prediction was considered clinically appropriate. Prediction could be improved by adding cancer-specific variables and considering competing risks. Our findings suggest that the equations are reasonable clinical tools for use in survivors of cancer in New Zealand. FUNDING: Auckland Medical Research Foundation, Health Research Council of New Zealand.

Selective under-representation of Pacific peoples in population estimates for health indicator measurements in Aotearoa New Zealand misinforms policy making.

BACKGROUND: The Census of Populations and Dwellings' is the five yearly population count of Aotearoa New Zealand. Best available populations (BAP) are subnational projections based on census data and demographic assumptions developed for healthcare planning and funding allocation but are also used as the denominator for health indicator monitoring. Pacific people are systematically undercounted, but the impact on health statistics is not well studied. For COVID-19 vaccination coverage, health service user (HSU) data were considered a more reliable denominator than BAP but introduced new biases. We aimed to understand how the choice of denominator population impacts estimates of population size and health system performance for Pacific people at a local level. METHODS: We described how declining census response rates affected population data quality. We compared BAP and HSU data at district level. For the indicators 'access to primary care' and 'cervical cancer screening uptake' we replaced currently used BAP denominators with HSU and examined the impact for different ethnic groups in different geographic districts. RESULTS: Overall Census 2018 response declined by 10%, but for Maori and Pacific people by 21% and 23%, respectively. This inequitably affected BAP accuracy. Census undercount was highest in the district with the largest Pacific populations, where HSU exceeded BAP most. Notably, 'access to primary care' for Pacific people in this district consistently exceeds 100%. Using BAP, both health indicators are currently estimated as highest for Pacific people compared to other ethnic groups, but when based on HSU, they dropped to lowest. Similar, but less pronounced trends occurred in other districts. Changes in trends over time for both indicators coincided mostly with adjustments in BAP, rather than changes in the numerators. CONCLUSIONS: The current use of BAP denominators for health statistics does not enable reliable monitoring of key health indicators for Pacific people. HSU denominators are also unsuitable for monitoring health. Exploring the feasibility of a real-time population register is strongly recommended as a new, transparent, way of obtaining more reliable, timely population data to guide policymaking and underpin a more equitable health system under the health reforms. Meanwhile, reporting of ethnic specific outcomes need to include a clear assessment of the potential for bias due to inaccurate population estimates.

The Prevalence and Management of Atrial Fibrillation in New Zealand Maori Detected through an Abdominal Aortic Aneurysm Screening Program.

BACKGROUND: Atrial fibrillation (AF) screening was incorporated into an abdominal aortic aneurysm screening (AAA) program for New Zealand (NZ) Maori. METHODS: AF screening was performed as an adjunct to AAA screening of Maori men aged 60-74 years and women aged 65-74 years registered with primary health care practices in Auckland, NZ. Pre-existing AF was determined through coded diagnoses or medications in the participant's primary care record. Subsequent audit of the record assessed accuracy of pre-screening coding, medication use and clinical follow-up. RESULTS: Among 1,933 people successfully screened, the prevalence of AF was 144 (7.4%), of which 46 (2.4% of the cohort) were patients without AF coded in the medical record. More than half of these were revealed to be known AF but that was not coded. Thus, the true prevalence of newly detected AF was 1.1% (n=21). An additional 48 (2.5%) of the cohort had been coded as AF but were not in AF at the time of screening. Among the 19 at-risk screen-detected people with AF, 10 started appropriate anticoagulation therapy within 6 months. Of the nine patients who did not commence anticoagulation therapy, five had a subsequent adverse clinical outcome in the follow-up period, including one with ischaemic stroke; two had contraindications to anticoagulants. Among those with previously diagnosed AF, the proportion receiving anticoagulation therapy rose from 57% pre-screening to 83% at 6 months post-screening (p<0.0001); among newly diagnosed AF the proportion rose from 0% to 53% (p<0.01). CONCLUSIONS: AF screening is a feasible low-cost adjunct to AAA screening with potential to reduce ethnic inequities in stroke incidence. However, effective measures are needed to ensure that high-risk newly diagnosed AF is managed according to best practice guidelines.

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.

Cardiovascular disease preventive medication dispensing for almost every New Zealander 65 years and over: a preventive treatment paradox?

OBJECTIVE: To describe the dispensing of cardiovascular disease (CVD) preventive medications among older New Zealanders with and without prior CVD or diabetes. METHODS: New Zealanders aged ≥65 years in 2013 were identified using anonymised linkage of national administrative health databases. Dispensing of blood pressure lowering (BPL), lipid lowering (LL) or antithrombotic (AT) medications, was documented, stratified by age and by history of CVD, diabetes, or neither. RESULTS: Of the 593,549 people identified, 32% had prior CVD, 14% had diabetes (of whom half also had prior CVD) and 61% had neither diagnosis. For those with prior CVD, between 79-87% were dispensed BPL and 73-79% were dispensed AT medications, across all age groups. In contrast, LL dispensing was lower than either BPL or AT in every age group, falling from 75% at age 65-69 years to 43% at 85+ years. For people with diabetes, BPL and LL dispensing was similar to those with prior CVD, but AT dispensing was approximately 20% lower. Among people without prior CVD or diabetes, both BPL and AT dispensing increased with age (from 39% and 17% at age 65-69 years to 56% and 35% at 85+ years respectively), whereas LL dispensing was 26-31% across the 65-84 year age groups, falling to 17% at 85+ years. CONCLUSION: The much higher dispensing of BPL and AT compared to LL medications with increasing age suggests a preventive treatment paradox for older people, with the medications most likely to cause adverse effects being dispensed most often.

Design and implementation of a Pacific intervention to increase uptake of urate-lowering therapy for gout: a study protocol.

BACKGROUND: Gout is a painful chronic disease which disrupts work and family life and can lead to chronic joint damage. Pacific people in Aotearoa/New Zealand experience significant inequities, with over three times the gout prevalence of the non-Pacific non-Maori populations. Pacific people receive less regular urate-lowering drugs to prevent gout flare-ups, and have nine times the hospitalisation from gout compared with non-Pacific non-Maori people. Rates for Indigenous Maori lie between Pacific and non-Pacific non-Maori. A long-established Collective comprising community members from the Pacific People's Health Advisory Group, clinical staff from the Pacific Practice-Based Research Network, and University of Auckland researchers have identified that improving Pacific urate-lowering therapy use as the research question of prime importance for improved health outcomes of Pacific people in South Auckland. Building on the existing knowledge, this study aims to develop, implement and evaluate a novel innovative intervention to improve the uptake of urate-lowering therapy by Pacific patients with gout. METHODS: Three-phase mixed methods co-design study using the Fa'afaletui research framework following the STROBE statement. Phase1 is observational times series of prevalence of patients with gout, proportion with urate blood-level monitoring and use of urate-lowering medication over past 5 years. In Phase 2 the Collective will workshop new interventions to address previous uptake barriers, using culturally-appropriate Talanga communications with results synthesised in line with Kakala principles. The designed intervention will be implemented and process and outcome evaluations conducted. Finally, an implementation framework will be produced to facilitate further roll-out. DISCUSSION: The study aims to enhance health and reduce inequities for Pacific people, contribute to creation of Pacific health knowledge and translation of research findings into Pacific health gains. Potential longer-term impact is a gout-management pathway for use throughout Aotearoa/New Zealand. Maori have similar issues with high gout prevalence and low urate-lowering therapy use hence the intervention is likely to translate to Maori healthcare. The project will contribute to Pacific research capacity and capability-building as well as general upskilling of community and practice members involved in the co-design processes. TRIAL REGISTRATION: The Australian New Zealand Clinical Trial Registry is in process, request number 38206, 1-09-2021.

Cardiovascular disease and its management among Pacific people: a systematic review by ethnicity and place of birth.

BACKGROUND: Pacific people experience a disproportionate burden of cardiovascular disease (CVD), whether they remain in their country of origin or migrate to higher-income countries, such as Australia, Aotearoa New Zealand or the United States of America. We sought to determine whether the CVD health needs of Pacific people vary according to their ethnicity or place of birth. METHODS: We conducted a systematic review of medical research databases and grey literature to identify relevant data published up to 2020. Texts were included if they contained original data stratified by Pacific-specific ethnicity or place of birth on the burden or management of CVD, and were assessed as having good quality using a National Heart, Lung, and Blood Institute quality assessment tool. The protocol for this review was registered with the Open Science Forum ( https://doi.org/10.17605/OSF.IO/X7NR6 ). RESULTS: Of 3679 texts identified, 310 full texts were reviewed and the quality of 23 of these assessed, using the pre-defined search strategy. Six items (four reports, one article, one webpage) of good quality met the review eligibility criteria. All included texts provided data on epidemiology but only one reported on the management of CVD. Four texts were of Pacific populations in Pacific Island countries and two were of Pacific diaspora in other countries. Data from the Global Burden of Disease study, which provided estimates for the greatest number of Pacific countries, showed substantial differences in mortality rates between Pacific countries for every CVD type. For example, the mortality rate per 100,000 for ischemic heart disease (IHD) ranged from 103.41 in the Cook Islands to 430.35 in the Solomon Islands. A New Zealand-based report showed differences in CVD rates by Pacific ethnicity (e.g. the age-standardised prevalence of IHD per 1,000 population in Auckland ranged from 107.8 (Niuean) to 138 among Cook Islands Maori (p < 0.001)). CONCLUSIONS: This review of published studies reveals that the epidemiology of CVD among Pacific people varies by specific ethnic groups, place of birth, and country of residence. There is a critical need for high-quality contemporary ethnic-specific Pacific data to respond to the diverse CVD health needs in these underrepresented groups.

Risk of major bleeding by ethnicity and socioeconomic deprivation among 488,107 people in primary care: a cohort study.

BACKGROUND: Antithrombotic medications (antiplatelets and anticoagulants) reduce the risk of cardiovascular disease (CVD), but with the disadvantage of increasing bleeding risk. Ethnicity and socioeconomic deprivation are independent predictors of major bleeds among patients without CVD, but it is unclear whether they are also predictors of major bleeds among patients with CVD or atrial fibrillation (AF) after adjustment for clinical variables. METHODS: Prospective cohort study of 488,107 people in New Zealand Primary Care (including 64,420 Maori, the indigenous people of New Zealand) aged 30-79 years who had their CVD risk assessed between 2007 and 2016. Participants were divided into three mutually exclusive subgroups: (1) AF with or without CVD (n = 15,212), (2) CVD and no AF (n = 43,790), (3) no CVD or AF (n = 429,105). Adjusted hazards ratios (adjHRs) were estimated from Cox proportional hazards models predicting major bleeding risk for each of the three subgroups to determine whether ethnicity and socioeconomic deprivation are independent predictors of major bleeds in different cardiovascular risk groups. RESULTS: In all three subgroups (AF, CVD, no CVD/AF), Maori (adjHR 1.63 [1.39-1.91], 1.24 [1.09-1.42], 1.57 [95% CI 1.45-1.70], respectively), Pacific people (adjHR 1.90 [1.58-2.28], 1.30 [1.12-1.51], 1.62 [95% CI 1.49-1.75], respectively) and Chinese people (adjHR 1.53 [1.08-2.16], 1.15 [0.90-1.47], 1.13 [95% CI 1.01-1.26], respectively) were at increased risk of a major bleed compared to Europeans, although for Chinese people the effect did not reach statistical significance in the CVD subgroup. Compared to Europeans, Maori and Pacific peoples were generally at increased risk of all bleed types (gastrointestinal, intracranial and other bleeds). An increased risk of intracranial bleeds was observed among Chinese and Other Asian people and, in the CVD and no CVD/AF subgroups, among Indian people. Increasing socioeconomic deprivation was also associated with increased risk of a major bleed in all three subgroups (adjHR 1.07 [1.02-1.12], 1.07 [1.03-1.10], 1.10 [95% CI 1.08-1.12], respectively, for each increase in socioeconomic deprivation quintile). CONCLUSION: Ethnicity and socioeconomic status should be considered in bleeding risk assessments to guide the use of antithrombotic medication for the management of AF and CVD.

Increases in early discharge following acute coronary syndrome hospitalisations and associated clinical outcomes in New Zealand between 2006 and 2015: ANZACS-QI-43 study.

BACKGROUND: International guidelines recommend early discharge for uncomplicated acute coronary syndrome (ACS) patients within 3 days; however, there is a paucity of contemporary literature regarding the safety of this strategy. AIMS: To report the trends in the proportion of ACS hospitalisations discharged within 3 days and their outcomes in New Zealand. METHODS: ACS hospitalisations 2006-2015 using national routinely collected data were categorised by length of stay (LOS) into ≤3, 4-5 and >5 days, excluding deaths during the index admission. Trend analysis of death, cardiovascular and bleeding events and their composites (net adverse clinical events) at 30-day and 1-year post-discharge were performed using generalised linear mixed regression models adjusting for covariates by LOS subgroups. RESULTS: Among 130 037 ACS hospitalisations, LOS ≤ 3 days increased from 32% in 2006 to 44% in 2016. This trend was observed for all demographics, ACS subtypes and management strategies. Event rates at 30 days and 1 year were the lowest for the LOS ≤3 days subgroup (all-cause mortality 1.6% and 9.1% respectively). Thirty-day and 1-year all-cause mortality rates were unchanged over time for this subgroup (adjusted odds ratio (95% confidence interval) of 1.011 (0.985-1.038) and 0.991 (0.979-1.003)), while net adverse clinical event rates significantly decreased (0.962 (0.950-0.973) and 0.972 (0.964-0.980) respectively). CONCLUSION: There was a substantial increase in early discharge post-ACS over 10 years. These patients were associated with reduction in adverse clinical events up to 1 year and no increase in all-cause mortality. These findings from a comprehensive national register suggest that guideline recommendations on early discharge after uncomplicated ACS are safe and appropriate.

Maori, Pacific, Aboriginal and Torres Strait Islander Women's Cardiovascular Health: Where Are the Opportunities to Make a Real Difference?

Maori and Pacific women in New Zealand and Aboriginal and Torres Strait Islander women in Australia are recognised as nurturers and leaders within their families and communities. However, women's wellbeing, and that of their communities, are affected by a high burden of cardiovascular disease experienced at a younger age than women from other ethnic groups. There has been little focus on the cardiovascular outcomes and strategies to address heart health inequities among Maori, Pacific, Aboriginal and Torres Strait Islander women. The factors contributing to these inequities are complex and interrelated but include differences in exposure to risk and protective factors, rates of multi-morbidity, and substantial gaps within the health system, which include barriers to culturally responsive, timely and appropriate cardiovascular care. Evidence demonstrates critical treatment gaps across the continuum of risk and disease, including assessment and management of cardiovascular risk in young women and time-critical access to and receipt of acute services. Cardiovascular disease in women impacts not only the individual, but their family and community, and the burden of living with disease limits women's capacity to fulfil their roles and responsibilities which support and sustain families and communities. Our response must draw on the strengths of Maori, Pacific, Aboriginal and Torres Strait Islander women, acknowledge health and wellbeing holistically, address the health and social needs of individuals, families and communities, and recognise that Indigenous women in New Zealand, Australia and across the Pacific must be involved in the design, development and implementation of solutions affecting their own health.

The population prevalence of undetected abdominal aortic aneurysm in New Zealand Maori.

BACKGROUND: The prevalence of abdominal aortic aneurysm (AAA) in Polynesian populations such as the New Zealand Maori has not been characterized. We measured this in a large population-based sample. METHODS: A cross-sectional population-based prevalence study was conducted as part of an AAA screening pilot; 2467 Maori men aged 54 to 74 years and 1526 women aged 65 to 74 years registered with a primary care practice in Auckland (New Zealand) were invited to be screened by abdominal ultrasound between June 2016 and March 2018. Patients with pre-existing AAA disease and those with terminal conditions or circumstances that would make them unlikely to benefit from screening were excluded. The prevalence rate of AAA in Maori women was calculated with a cutoff definition of 27 mm as well as with the normal 30-mm definition (used in men). A log-binomial regression model estimated the prevalence rate at exactly 65 years for the purpose of comparison with screened populations in the United Kingdom. RESULTS: The crude prevalence rate of undiagnosed AAA in Maori men aged 60 to 74 years was 3.6%. In women, it was 1.7% at the 30-mm threshold and 2.3% at 27 mm. The prevalence rate at exactly 65 years of age was calculated from the log-binomial regression model to be 2.7% (confidence interval [CI], 2.0%-3.8%) in men, 0.9% (CI, 0.4%-2.2%) in women at the 30-mm threshold, and 1.5% (CI, 0.7%-3.0%) in women at the 27-mm threshold. Among smokers, the crude prevalence rates were 7.5% (CI, 4.9%-11.5%) in men and 6.9% (CI, 4.1%-11.5%) in women (30 mm+). CONCLUSIONS: The prevalence of undiagnosed AAA in New Zealand Maori men is considerably higher than in screened populations of equivalent age in the United Kingdom and Sweden. Prevalence rates in New Zealand Maori women are close to those of screened British men. New Zealand should consider implementing a population-based screening program for Maori men and conduct further research into the health impact of screening Maori women.

Predicting Bleeding Risk to Guide Aspirin Use for the Primary Prevention of Cardiovascular Disease: A Cohort Study.

Background: Many prognostic models for cardiovascular risk can be used to estimate aspirin's absolute benefits, but few bleeding risk models are available to estimate its likely harms. Objective: To develop prognostic bleeding risk models among persons in whom aspirin might be considered for the primary prevention of cardiovascular disease (CVD). Design: Prospective cohort study. Setting: New Zealand primary care. Participants: The study cohort comprised 385 191 persons aged 30 to 79 years whose CVD risk was assessed between 2007 and 2016. Those with indications for or contraindications to aspirin and those who were already receiving antiplatelet or anticoagulant therapy were excluded. Measurements: For each sex, Cox proportional hazards models were developed to predict major bleeding risk; participants were censored at the earliest of the date on which they first met an exclusion criterion, date of death, or study end date (30 June 2017). The main models included the following predictors: demographic characteristics (age, ethnicity, and socioeconomic deprivation), clinical measurements (systolic blood pressure and ratio of total-high-density lipoprotein cholesterol), family history of premature CVD, medical history (smoking, diabetes, bleeding, peptic ulcer disease, cancer, chronic liver disease, chronic pancreatitis, or alcohol-related conditions), and medication use (nonsteroidal anti-inflammatory agents, corticosteroids, and selective serotonin reuptake inhibitors). Results: During 1 619 846 person-years of follow-up, 4442 persons had major bleeding events (of which 313 [7%] were fatal). The main models predicted a median 5-year bleeding risk of 1.0% (interquartile range, 0.8% to 1.5%) in women and 1.1% (interquartile range, 0.7% to 1.6%) in men. Plots of predicted-against-observed event rates showed good calibration throughout the risk range. Limitation: Hemoglobin level, platelet count, and body mass index were excluded from the main models because of high numbers of missing values, and the models were not externally validated in non-New Zealand populations. Conclusion: Prognostic bleeding risk models were developed that can be used to estimate the absolute bleeding harms of aspirin among persons in whom aspirin is being considered for the primary prevention of CVD. Primary Funding Source: The Health Research Council of New Zealand.

Personalized Prediction of Cardiovascular Benefits and Bleeding Harms From Aspirin for Primary Prevention: A Benefit-Harm Analysis.

Background: Whether the benefits of aspirin for the primary prevention of cardiovascular disease (CVD) outweigh its bleeding harms in some patients is unclear. Objective: To identify persons without CVD for whom aspirin would probably result in a net benefit. Design: Individualized benefit-harm analysis based on sex-specific risk scores and estimates of the proportional effect of aspirin on CVD and major bleeding from a 2019 meta-analysis. Setting: New Zealand primary care. Participants: 245 028 persons (43.6% women) aged 30 to 79 years without established CVD who had their CVD risk assessed between 2012 and 2016. Measurements: The net effect of aspirin was calculated for each participant by subtracting the number of CVD events likely to be prevented (CVD risk score × proportional effect of aspirin on CVD risk) from the number of major bleeds likely to be caused (major bleed risk score × proportional effect of aspirin on major bleeding risk) over 5 years. Results: 2.5% of women and 12.1% of men were likely to have a net benefit from aspirin treatment for 5 years if 1 CVD event was assumed to be equivalent in severity to 1 major bleed, increasing to 21.4% of women and 40.7% of men if 1 CVD event was assumed to be equivalent to 2 major bleeds. Net benefit subgroups had higher baseline CVD risk, higher levels of most established CVD risk factors, and lower levels of bleeding-specific risk factors than net harm subgroups. Limitations: Risk scores and effect estimates were uncertain. Effects of aspirin on cancer outcomes were not considered. Applicability to non-New Zealand populations was not assessed. Conclusion: For some persons without CVD, aspirin is likely to result in net benefit. Primary Funding Source: Health Research Council of New Zealand.

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.

Cardiovascular disease risk prediction equations in 400 000 primary care patients in New Zealand: a derivation and validation study.

BACKGROUND: Most cardiovascular disease risk prediction equations in use today were derived from cohorts established last century and with participants at higher risk but less socioeconomically and ethnically diverse than patients they are now applied to. We recruited a nationally representative cohort in New Zealand to develop equations relevant to patients in contemporary primary care and compared the performance of these new equations to equations that are recommended in the USA. METHODS: The PREDICT study automatically recruits participants in routine primary care when general practitioners in New Zealand use PREDICT software to assess their patients' risk profiles for cardiovascular disease, which are prospectively linked to national ICD-coded hospitalisation and mortality databases. The study population included male and female patients in primary care who had no prior cardiovascular disease, renal disease, or congestive heart failure. New equations predicting total cardiovascular disease risk were developed using Cox regression models, which included clinical predictors plus an area-based deprivation index and self-identified ethnicity. Calibration and discrimination performance of the equations were assessed and compared with 2013 American College of Cardiology/American Heart Association Pooled Cohort Equations (PCEs). The additional predictors included in new PREDICT equations were also appended to the PCEs to determine whether they were independent predictors in the equations from the USA. FINDINGS: Outcome events were derived for 401 752 people aged 30-74 years at the time of their first PREDICT risk assessment between Aug 27, 2002, and Oct 12, 2015, representing about 90% of the eligible population. The mean follow-up was 4·2 years, and a third of participants were followed for 5 years or more. 15 386 (4%) people had cardiovascular disease events (1507 [10%] were fatal, and 8549 [56%] met the PCEs definition of hard atherosclerotic cardiovascular disease) during 1 685 521 person-years follow-up. The median 5-year risk of total cardiovascular disease events predicted by the new equations was 2·3% in women and 3·2% in men. Multivariable adjusted risk increased by about 10% per quintile of socioeconomic deprivation. Maori, Pacific, and Indian patients were at 13-48% higher risk of cardiovascular disease than Europeans, and Chinese or other Asians were at 25-33% lower risk of cardiovascular disease than Europeans. The PCEs overestimated of hard atherosclerotic cardiovascular disease by about 40% in men and by 60% in women, and the additional predictors in the new equations were also independent predictors in the PCEs. The new equations were significantly better than PCEs on all performance metrics. INTERPRETATION: We constructed a large prospective cohort study representing typical patients in primary care in New Zealand who were recommended for cardiovascular disease risk assessment. Most patients are now at low risk of cardiovascular disease, which explains why the PCEs based mainly on old cohorts substantially overestimate risk. Although the PCEs and many other equations will need to be recalibrated to mitigate overtreatment of the healthy majority, they also need new predictors that include measures of socioeconomic deprivation and multiple ethnicities to identify vulnerable high-risk subpopulations that might otherwise be undertreated. FUNDING: Health Research Council of New Zealand, Heart Foundation of New Zealand, and Healthier Lives National Science Challenge.

One in four major ischaemic heart disease events are fatal and 60% are pre-hospital deaths: a national data-linkage study (ANZACS-QI 8).

Aims: The aim of this study is to determine proportions of major ischaemic heart disease (IHD) events that are fatal and where they occur, in an era of rapidly falling IHD mortality. Methods and Results: Individual person linkage of national data sets identified all IHD hospitalizations and deaths in New Zealand from December 2008 to November 2010. Outcome measures were proportions of people: (i) hospitalized with IHD and alive at 28 days; (ii) hospitalized with IHD and died within 28 days; (iii) hospitalized for a non-IHD cause and died from IHD within 28 days; and (iv) not hospitalized and died from IHD. Three event definitions were used [broad-balanced: IHD deaths and IHD hospitalizations, unbalanced: IHD deaths and myocardial infarction (MI) hospitalizations, and narrow-balanced: MI deaths and MI hospitalizations]. About 37 867 IHD hospitalizations and 9409 IHD deaths were identified using the broad IHD definition. Approximately one-quarter of IHD events were fatal: 4% were deaths within 28 days of an IHD hospitalization, 6% were IHD deaths within 28 days of a non-IHD hospitalization, and 14% were non-hospitalized IHD deaths. Using different event definitions, overall case fatality varied from 24­25% (broad and narrow balanced) to 37­39% (unbalanced), whereas the proportion of all deaths that were non-hospitalized was approximately 60%. Forty per cent of deaths were first-ever events that manifested as non-hospitalized IHD deaths. Conclusion: About one-quarter of IHD are fatal, although the proportion is dependent on disease definitions and age. About 60% of all IHD deaths occur out of hospital, and of these 60% are in people not previously hospitalized for IHD.

Annual Risk of Major Bleeding Among Persons Without Cardiovascular Disease Not Receiving Antiplatelet Therapy.

Importance: A decision to initiate aspirin therapy for primary prevention of cardiovascular disease (CVD) requires consideration of both treatment benefits and harms. The most significant harm associated with aspirin is major bleeding, yet there is a paucity of data on bleeding risk in suitable community populations. Objective: To determine the risk of major bleeding among people without CVD who are not receiving antiplatelet therapy. Design, Setting, and Participants: Prospective cohort study of 359 166 individuals aged 30 to 79 years receiving primary care in New Zealand who had CVD risk assessment between 2002 and 2015. Participants were censored at the earliest date on which they had a first major bleeding event, died, or met any baseline cohort exclusion criteria or the study end date of December 31, 2015. Analyses were repeated after excluding people with medical conditions associated with increased bleeding risk (non-high-risk cohort; n=305 057) and after further excluding people receiving other medications associated with increased bleeding risk (nonmedication cohort; n=240 254). Exposures: Sex and age group in 10-year bands from 30 to 79 years. Main Outcomes and Measures: Risk of a major bleeding event (hospitalization or death associated with bleeding); nonfatal gastrointestinal tract bleeding; and gastrointestinal tract bleeding-related case fatality. Results: Mean participant age was 54 years (SD, 10 years), 44% were women, and 57% were European. Among the 359 166 individuals in the baseline cohort, 3976 had a major bleeding event during 1 281 896 person-years of follow-up. Most had gastrointestinal (GI) bleeding (n=2910 [73%]). There were 274 fatal bleeding events (7%), of which 153 were intracerebral. The risk of a nonfatal GI bleeding event per 1000 person-years was 2.19 (95% CI, 2.11-2.27), 1.77 (95% CI, 1.69-1.85) and 1.61 (95% CI, 1.52-1.69), in the baseline, non-high-risk, and nonmedication cohorts, respectively. Case fatality associated with GI bleeding was 3.4% (95% CI, 2.2%-4.1%), 4.0% (95% CI, 3.2%-5.1%), and 4.6% (95% CI, 3.6%-6.0%) in the baseline, non-high-risk, and nonmedication cohorts, respectively. Conclusions and Relevance: In a population not receiving antiplatelet therapy, the annual risk of major bleeding events and nonfatal major bleeding was estimated. These findings could inform population-level guidelines for primary prevention of CVD.

Ethnic Differences in Coronary Revascularisation following an Acute Coronary Syndrome in New Zealand: A National Data-linkage Study (ANZACS-QI 12).

BACKGROUND: The aim of this study was to describe ethnic differences in angiography and revascularisation rates following an acute coronary syndrome (ACS) in New Zealand. METHODS: National hospitalisation and mortality data were anonymously linked to determine receipt of angiography and revascularisation for 30-84 year-olds hospitalised with ACS between 2007 and 2012. Multilevel Cox regression, accounting for individual factors and admitting hospital, was used to estimate adjusted procedural rates within 30 days of admission. RESULTS: Of the 50,324 ACS patients included, 10% were Maori, 4% Pacific, 3% Indian and 83% New Zealand European or Other ethnicities (NZEO). A larger proportion of Maori (48%) than NZEO (36%), Pacific (19%) and Indian (14%) patients were admitted to hospitals without catheterisation facilities. More Maori and Pacific (22-24%) than NZEO and Indian patients (12-13%) had severe comorbidities. Maori and Pacific were less likely than NZEO patients to receive angiography (adjusted HRs 0.94 [0.91-0.98] and 0.93 [0.87-0.98] respectively) and revascularisation (adjusted HRs 0.79 [0.75-0.83] and 0.77 [0.71-0.83]), even after adjusting for important demographic and clinical factors. CONCLUSIONS: A higher comorbidity burden in Maori and Pacific patients and reduced access to catheterisation facilities for non-urban Maori contributed to lower procedure rates after ACS admission. Ethnic differences remained after adjustment for these factors and require further investigation.

Widening ethnic inequities in heart failure incidence in New Zealand.

OBJECTIVE: Ethnic inequities in heart failure (HF) have been documented in several countries. This study describes New Zealand (NZ) trends in incident HF hospitalisation by ethnicity between 2006 and 2018. METHODS: Incident HF hospitalisations in ≥20-year-old subjects were identified through International Classification of Diseases, 10th Revision-coded national hospitalisation records. Incidence was calculated for different ethnic, sex and age groups and were age standardised. Trends were estimated with joinpoint regression. RESULTS: Of 116 113 incident HF hospitalisations, 12.8% were Maori, 5.7% Pacific people, 3.0% Asians and 78.6% Europeans/others. 64% of Maori and Pacific patients were aged <70 years, compared with 37% of Asian and 19% of European/others. In 2018, incidence rate ratios compared with European/others were 6.0 (95% CI 4.9 to 7.3), 7.5 (95% CI 6.0 to 9.4) and 0.5 (95% CI 0.3 to 0.8) for Maori, Pacific people and Asians aged 20-49 years; 3.7 (95% CI 3.4 to 4.0), 3.6 (95% CI 3.2 to 4.1) and 0.5 (95% CI 0.4 to 0.6) for Maori, Pacific people and Asians aged 50-69 years; and 1.5 (95% CI 1.4 to 1.6), 1.5 (95% CI 1.3 to 1.7) and 0.5 (95% CI 0.5 to 0.6) for Maori, Pacific people and Asians aged ≥70 years. Between 2006 and 2018, ethnicity-specific rates diverged in ≥70-year-old subjects due to a decline in European/others (annual percentage change (APC) -2.0%, 95% CI -2.5% to -1.6%) and Asians (APC -3.3%, 95% CI -4.4% to -2.1%), but rates remained unchanged for Maori and Pacific people. In contrast, regardless of ethnicity, rates either increased or remained unchanged in <70-year-old subjects. CONCLUSION: Ethnic inequities in incident HF hospitalisation have widened in NZ over the past 13 years. Urgent action is required to address the predisposing factors that lead to development of HF in Maori and Pacific people.

Maori and Pacific families' experiences and perspectives of cardiovascular care; A qualitative study.

OBJECTIVE: This study aimed to understand the reasons behind evidence-practice gaps and inequities in cardiovascular care for Maori and Pacific people, as evidenced by the experiences and perspectives of patients and their families. METHODS: The research was guided by Maori and Pacific worldviews, incorporating Kaupapa Maori Theory and Pacific conceptual frameworks and research methodologies. Template analysis was used to analyse interview data from 61 Maori and Pacific people who had experienced a cardiovascular disease (CVD) risk assessment, acute coronary syndrome, and/or heart failure. RESULTS: The range of experiences relating to participants' heart health journeys are presented in five main themes: Context, Mana (maintaining control and dignity), Condition, People and Journey. CONCLUSIONS: Maori and Pacific people want to take charge of their heart health but face challenges. Participants described important obligations to family, community and tikanga (the culturally correct way of doing things). Participants described times when health care undermined existing responsibilities, their dignity and/or their mana, and they felt excluded from treatment as a result. IMPLICATIONS FOR PUBLIC HEALTH: Good reciprocal communication, stemming from a high-quality relationship is essential for successful outcomes. A workforce that is representative of the population it serves and is culturally safe lays the foundation for excellence in care.