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.

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.

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.

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.

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.

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.

ANZACS-QI Heart Failure Registry: a new approach using age-stratified sampling of hospital discharges to guide quality improvement (ANZACS-QI 79).

Heart failure is a major healthcare problem in New Zealand. The Acute Decompensated Heart Failure (ADHF) Registry was introduced in 2015, and has identified the need for quality improvement strategies to improve care of patients hospitalised with heart failure. In this paper, we describe the implementation of the revised ANZACS-QI Heart Failure Registry, which has a primary aim to support evidence-based management of and quality improvement measures for patients who are hospitalised with heart failure in New Zealand. Taking the learnings from the initial experience with the ADHF Registry, the revised ANZACS-QI Heart Failure Registry i) utilises age-stratified sampling of hospital discharge coding to identify a representative heart failure cohort, ii) utilises existing ANZACS-QI infrastructure for data-linkage to reduce the burden of manual data entry, iii) receives governance from the Heart Failure Working Group, and iv) focusses on established quality improvement indicators for heart failure management.

Is serum urate causally associated with incident cardiovascular disease?

OBJECTIVE: With studies reporting both positive and negative associations, the influence of serum urate on incident cardiovascular disease (CVD) is uncertain. We sought to determine whether serum urate is causally associated with incident CVD. METHODS: Participants were aged 30-80 years and were screened for CVD risk in primary care between 2006 and 2009. Participants had blood pressure, lipids, age and ethnic group recorded at assessment, with record linkage providing drug dispensing, hospital diagnoses and laboratory test results. Outcomes were derived from hospital diagnoses and mortality records until December 2009. Cox models were used to assess the influence of exposures on outcomes. RESULTS: A total of 78 707 people, free of CVD, were enrolled, and 1328 CVD events occurred during follow-up. Serum urate was recorded before baseline assessment in 43% (34 008/78 707) of participants. After adjustment for confounding factors, a 2 s.d. difference in serum urate (0.45 vs 0.27 mmol/l) was associated with a hazard ratio (HR) of 1.56 (95% CI 1.32, 1.84). This was more than double that of the equivalent distributional change in high-density lipoprotein cholesterol (adjusted HR 1.22) and one-third greater than that for HbA1c (adjusted HR 1.41). CONCLUSION: Serum urate is likely to be causally associated with CVD. This supports public health action to reduce urate levels in populations with significant burdens of the disease.

Risk of cardiovascular disease in cancer survivors: A cohort study of 446,384 New Zealand primary care patients.

BACKGROUND: Given advances in the management of cancer, it is increasingly important for clinicians to appropriately manage the risk of cardiovascular disease (CVD) among cancer survivors. It is unclear whether CVD risk is increased among cancer survivors overall, and there is inconsistency in evidence to date about CVD incidence and mortality by cancer type. METHODS: Patients aged 30-74 years entered an open cohort study at the time of first CVD risk assessment, between 2004 and 2018, in primary care in New Zealand. Patients with established CVD or cancer within 2 years prior to study entry were excluded. Cancer diagnosis (1995-2016) was determined from a national cancer registry. Cause-specific hazard models were used to examine the association between history of cancer and two outcomes: (1) CVD-related hospitalization and/or death and (2) CVD death. RESULTS: The study included 446,384 patients, of whom 14,263 (3.2%) were cancer survivors. Risk of CVD hospitalization and/or death was increased among cancer survivors compared with patients without cancer at cohort entry (multivariable-adjusted hazard ratio, mHR, 1.11, 95% CI 1.05-1.18), more so for CVD death (1.31, 1.14-1.52). Risk of CVD hospitalization and/or death was increased in patients with myeloma (2.66, 1.60-4.42), lung cancer (2.19, 1.48-3.24) and non-Hodgkin lymphoma (1.90, 1.42-2.54), but not for some cancers (e.g., colorectal, 0.87, 0.71-1.06). Risk of CVD death was increased in several cancer types including melanoma (1.73, 1.25-2.38) and breast cancer (1.56, 1.16-2.11). CONCLUSION: CVD risk management needs to be prioritized among cancer survivors overall, and particularly in those with myeloma, lung cancer and non-Hodgkin lymphoma given consistent evidence of increased risk.

Investigation and treatment after non-ST segment elevation acute coronary syndrome for patients presenting to rural or urban hospitals in Aotearoa New Zealand: ANZACS-QI 75.

AIMS: Compare the care patients with non-ST segment elevation acute coronary syndrome (NSTEACS) received in Aotearoa New Zealand depending on the rural-urban category of the hospital they are first admitted to. METHODS: Patients with NSTEACS investigated with invasive coronary angiogram between 1 January 2014 and 31 December 2019 were included. There were three hospital categories (routine access to percutaneous coronary intervention [urban interventional], other urban [urban non-interventional] and rural) and three ethnicity categories (Maori, Pacific and non-Maori/non-Pacific). Clinical performance measures included: angiography ≤3 days, assessment of left ventricular ejection fraction (LVEF) and prescription of secondary prevention medication. RESULTS: Of 26,779 patients, 66.2% presented to urban-interventional, 25.6% to urban non-interventional and 8.2% to rural hospitals. A smaller percentage of patients presenting to urban interventional than urban non-interventional and rural hospitals were Maori (8.1%, 17.0% and 13.0%). Patients presenting to urban interventional hospitals were more likely to receive timely angiography than urban non-interventional or rural hospitals (78.5%, 60.8% and 63.1%). They were also more likely to have a LVEF assessment (78.5%, 65.4% and 66.3%). In contrast, the use of secondary prevention medications at discharge was similar between hospital categories. Maori and Pacific patients presenting to urban interventional hospitals were less likely than non-Maori/non-Pacific to receive timely angiography but more likely to have LVEF assessed. However, LVEF assessment and timely angiography in urban non-interventional and rural hospitals were lower than in urban interventional hospitals for both Maori and non-Maori/non-Pacific. CONCLUSIONS: Patients presenting to urban hospitals without routine interventional access and rural hospitals were less likely to receive LVEF assessment or timely angiography. This disproportionately impacts Maori, who are more likely to live in these hospital catchments.

Are competing-risk models superior to standard Cox models for predicting cardiovascular risk in older adults? Analysis of a whole-of-country primary prevention cohort aged ≥65 years.

BACKGROUND: Both cardiovascular disease (CVD) risk and deaths from non-CVD causes, which may preclude a CVD event, increase with age. We evaluated whether accounting for the competing risk of non-CVD death improves the performance of CVD risk-prediction equations in older adults. METHODS: All New Zealanders aged ≥65 years in 2012 without a prior CVD hospitalization were identified by anonymized linkage of eight routinely collected national health data sets. Sex-specific equations estimating the 5-year risk of a fatal or non-fatal CVD event were constructed using standard Cox and Fine-Gray (competing-risk) approaches. The pre-specified predictors were: age, ethnicity, deprivation level, diabetes, atrial fibrillation and baseline preventive pharmacotherapy. Model performance was evaluated by assessing calibration and discrimination in the overall cohort and in ethnic and age-specific subgroups. RESULTS: Among 360 443 people aged ≥65 years with 1 615 412 person-years of follow-up, 14.6% of men and 12.1% of women had a first CVD event, whereas 8.5% of men and 7.6% of women died from a non-CVD cause. Standard Cox models overestimated the mean predicted the 5-year CVD risk by ∼1% overall and by 5-6% in the highest risk deciles. The mean predicted CVD risk from the Fine-Gray models approximated the observed risk overall, although slight underestimation occurred in some subgroups. Discrimination was similar for both models. CONCLUSIONS: In a whole-of-country primary prevention cohort aged ≥65 years, standard Cox models overestimated the 5-year CVD risk whereas the Fine-Gray models were generally better calibrated. New CVD risk equations that take competing risks into account should be considered for older people.

Predicting cardiovascular disease risk across the atherosclerotic disease continuum.

AIMS: Cardiovascular disease (CVD) guidelines dichotomize populations into primary and secondary prevention. We sought to develop a risk equation for secondary prevention of CVD that complements existing equations for primary prevention of CVD, and to describe the distributions of CVD risk across the population. METHODS AND RESULTS: Adults aged 30-79 years who had routine CVD risk assessment in 2007-16 were identified from a large primary care cohort (PREDICT) with linkage to national and regional datasets. The 5-year risk of developing CVD among people without atherosclerotic CVD (ASCVD) was calculated using published equations (PREDICT-1°). A new risk equation (PREDICT-2°) was developed from Cox regression models to estimate the 5-year risk of CVD event recurrence among patients with known ASCVD. The outcome for both equations was hospitalization for a CVD event or cardiovascular death. Of the 475 161 patients, 12% (57 061) had ASCVD. For those without ASCVD, median (interquartile range) 5-year risks with the PREDICT-1° score were women 2.2% (1.2-4.2%), men 3.5% (2.0-6.6%), and whole group 2.9% (1.6-5.5%). For those with ASCVD, the 5-year risks with the new PREDICT-2° equation were women 21% (15-33%), men 23% (16-35%), and whole group 22% (16-34%). CONCLUSION: We developed CVD risk scores for people with ASCVD (PREDICT-2°) to complement the PREDICT-1° scores. Median CVD risk is eight-fold higher among those with ASCVD than those without; however, there was overlap and the widest distribution of CVD risk was among people with ASCVD. This study describes a CVD risk continuum and the limitations of a 'one size fits all' approach to assessing risk in people with ASCVD.

Identification of clinically relevant cohorts of people with heart failure from electronic health data in Aotearoa: potential, pitfalls and a plan.

Heart failure (HF) is associated with high morbidity and mortality and contributes to substantial burden of disease, significant inequities and high healthcare cost globally as well as in Aotearoa. Management of chronic HF is driven by HF phenotype, defined by left ventricular ejection fraction (EF), as only those with reduced ejection fraction (HFrEF) have been shown to experience reduced mortality and morbidity with long-term pharmacotherapy. To ensure appropriate and equitable implementation of HF management we need to be able to identify clinically relevant cohorts of patients with HF, in particular, those with HFrEF. The ideal HF registry would incorporate and link HF diagnoses and phenotype from primary and secondary care with echocardiography and pharmacotherapy data. In this article we consider several options for identifying such cohorts from electronic health data in Aotearoa, as well as the potential and pitfalls of these options. Given the urgent need to identify people with HF according to EF phenotype, the options for identifying them from electronic health data, and the opportunities presented by health system reform, including a focus on digital solutions, we recommend the following four actions, with oversight from a national HF working group: 1) Establish a HF registry based on random and representative sampling of HF admissions; 2) investigate obtaining HF diagnosis and EF-phenotype from primary care-coded data; 3) amalgamate national echocardiography data; and 4) investigate options to enable the systematic collection of HF diagnosis and EF-phenotype from outpatient attendances. Future work will need to consider reliability and concordance of data across sources. The case for urgent action in Aotearoa is compounded by the stark inequities in the burden of HF, the likely contribution of health service factors to these inequities and the legislative requirement under the Pae Ora (Healthy Futures) Act 2022 that "the health sector should be equitable, which includes ensuring Maori and other population groups - (i) have access to services in proportion to their health needs; and (ii) receive equitable levels of service; and (iii) achieve equitable health outcomes".

Cardiovascular preventive pharmacotherapy stratified by predicted cardiovascular risk: a national data linkage study.

AIMS: Cardiovascular disease (CVD) risk management guided by predicted CVD risk is widely recommended internationally. This is the first study to examine CVD preventive pharmacotherapy in a whole-of-country primary prevention population, stratified by CVD risk. METHODS AND RESULTS: Anonymized individual-level linkage of New Zealand administrative health and non-health data identified 2 250 201 individuals without atherosclerotic CVD, alive, and aged 30-74 years on 31 March 2013. We identified individuals with ≥1 dispensing by community pharmacies of blood pressure lowering (BPL) and/or lipid-lowering (LL) medications at baseline (1 October 2012-31 March 2013) and in 6-month periods between 1 April 2013 and 31 March 2016. Individuals were stratified using 5-year CVD risk equations specifically developed for application in administrative datasets. One-quarter of individuals had ≥5% 5-year risk (the current New Zealand guideline threshold for discussing preventive medications) and 5% met the ≥15% risk threshold for recommended dual therapy. By study end, dual therapy was dispensed to 2%, 18%, 34%, and 49% of individuals with <5%, 5-9%, 10-14%, and ≥15% 5-year risk, respectively. Among those dispensed baseline dual therapy, 83-89% across risk strata were still treated after 3 years. Dual therapy initiation during follow-up occurred among only 13% of high-risk individuals untreated at baseline. People without diabetes and those aged ≥65 years were more likely to remain untreated. CONCLUSION: Cardiovascular disease primary preventive pharmacotherapy was strongly associated with predicted CVD risk and, once commenced, was generally continued. However, only half of high-risk individuals received recommended dual therapy and treatment initiation was modest. Individually linked administrative datasets can identify clinically relevant quality improvement opportunities for entire 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.