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.
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.
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. Māori, 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.
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.
Health Research Council of New Zealand, Heart Foundation of New Zealand, and Healthier Lives National Science Challenge.
To determine 28‐day and one‐year case fatality in patients hospitalised with acute coronary syndromes (ACS) and identify factors associated with mortality.
All New Zealand residents admitted with ACS ...between 2007 and 2009 were followed for one year using individual patient linkage of national hospitalisation and mortality datasets. Deaths from any cause were used to calculate 28‐day and one‐year case fatality. Cox‐proportional hazards models were constructed to identify factors associated with mortality after an ACS hospitalisation.
The cohort included 42,920 ACS patients. Case fatality increased steeply with age. Māori and Pacific peoples had 1.5 times the risk of 28‐day, and twice the risk of one‐year, mortality as Europeans/Others. Low (compared to high) socioeconomic status was associated with significantly higher mortality at 28 days but not one year. Patients with unstable angina had half the risk of short‐term mortality as NSTEMI patients, whereas STEMI patients had double the NSTEMI risk.
The major determinant of increasing case fatality was increasing age. There were also substantial differences in case fatality by ethnicity, deprivation and diagnostic category. Further research is needed to explore the possible mechanisms by which ethnic and deprivation disparities occur and effective strategies to address them.
Rates of acute rheumatic fever and chronic rheumatic heart disease in Aboriginal people, Torres Strait Islanders and Māori continue to be unacceptably high. The impact of rheumatic heart disease is ...inequitable on these populations as compared with other Australians and New Zealanders. The associated cardiac morbidity, including the development of rheumatic valve disease, and cardiomyopathy, with possible sequelae of heart failure, development of atrial fibrillation, systemic embolism, transient ischaemic attacks, strokes, endocarditis, the need for interventions including cardiac surgery, and impaired quality of life, and shortened life expectancy, has major implications for the individual. The adverse health and social effects may significantly limit education and employment opportunities and increase dependency on welfare. Additionally there may be major adverse impacts on family and community life. The costs in financial terms and missed opportunities, including wasted young lives, are substantial. Prevention of acute rheumatic fever is dependent on the timely diagnosis and treatment of sore throats and skin infections in high-risk groups. Both Australia and New Zealand have registries for acute rheumatic fever but paradoxically neither includes all cases of chronic rheumatic heart disease many of whom would benefit from close surveillance and follow-up. In New Zealand and some Australian States there are programs to give secondary prophylaxis with penicillin, but these are not universal. Surgical outcomes for patients with rheumatic valvular disease are better for valve repair than for valve replacement. Special attention to the selection of the appropriate valve surgery and valve choice is required in pregnant women. It may be necessary to have designated surgical units managing Indigenous patients to ensure high rates of surgical repair rather than valve replacement. Surgical guidelines may be helpful. Long-term follow-up of the outcomes of surgery in Indigenous patients with rheumatic heart disease is required. Underpinning these strategies is the need to improve poverty, housing, education and employment. Cultural empathy with mutual trust and respect is essential. Involvement of Indigenous people in decision making, design, and implementation of primary and secondary prevention programs, is mandatory to reduce the unacceptably high rates of rheumatic heart disease.
National cardiovascular disease (CVD) guidelines recommend that adults have cholesterol levels monitored regularly. However, little is known about the extent and equity of cholesterol testing in New ...Zealand.
To investigate the distribution and frequency of blood lipid testing by sociodemographic status in Auckland, New Zealand.
We anonymously linked five national health datasets (primary care enrolment, laboratory tests, pharmaceuticals, hospitalisations and mortality) to identify adults aged ≥25 years without CVD or diabetes who had their lipids tested in 2006-2010, by age, gender, ethnicity and area of residence and deprivation. Multivariate logistic regression was used to estimate the likelihood of testing associated with these factors.
Of the 627 907 eligible adults, 66.3% had at least one test between 2006 and 2010. Annual testing increased from 24.7% in 2006 to 35.1% in 2010. Testing increased with age similarly for men and women. Indian people were 87% more likely than New Zealand European and Others (NZEO) to be tested, Pacific people 8% more likely, but rates for Maori were similar to NZEO. There was marked variation within the region, with residents of the most deprived areas less likely to be tested than residents in least deprived areas.
Understanding differences within and between population groups supports the development of targeted strategies for better service utilisation. While lipid testing has increased, sociodemographic variations persist by place of residence, and deprivation. Of the high CVD risk populations, lipid testing for Maori and Pacific is not being conducted according to need.
To compare the cardiovascular disease (CVD) risk profiles of Indian and European patients from routine primary care assessments in the northern region of New Zealand.
Anonymous CVD risk profiles were ...extracted from PREDICT (a web‐based decision support program) for Indian and European patients aged 35–74 years. Linear regression models were used to obtain mean differences adjusted for age, gender and deprivation.
At recruitment, Indian participants (n=8,830) were younger than Europeans (n=47,091), in keeping with national guidelines that recommend earlier CVD risk assessment for Indians. Compared with Europeans, a greater proportion of Indian participants lived in areas of higher deprivation and had a two to four‐fold greater burden of diabetes in all age groups. Indian participants had a significantly lower proportion of smokers and a lower mean systolic blood pressure. The respective cardiovascular risk factor profiles lead to similar age‐adjusted Framingham five‐year CVD risk scores.
National data sources indicate that there are higher rates of hospitalisations and deaths from CVD in Indians compared with Europeans. Our study found similar predicted CVD risk in these two populations despite markedly different clustering of risk factors, suggesting that the Framingham risk equation may underestimate risk in Indians. There is a need for better ethnicity coding to identify all South Asian ethnicities.
To describe patterns of statin use and predictors of poor maintenance over a 3-year period following an acute coronary syndrome (ACS).
National hospitalisation, mortality and pharmaceutical ...dispensing data were linked for all subjects aged 35-84 years discharged from a public hospital with an ACS in New Zealand in 2007. A Medication Possession Ratio (MPR; percentage of follow-up days patients were dispensed statins) was calculated for each patient. Adequate maintenance was defined by a MPR ≥80%.
In 2007, 11 348 patients aged 35-84 years were discharged from hospital with ACS. Within 90 days of discharge, 83% had received a statin. Over the follow-up period, 66% were adequately maintained on a statin (MPR ≥80%): 69% in the first year, 67% in the second year and 66% in the third year. Patients taking statins prior to admission and those who underwent a coronary procedure were 20-50% more likely to have a MPR ≥80% over 3 years than others. In contrast, people aged 35-45 years and those of Maori or Pacific ethnicity were 13-25% less likely to have a MPR ≥80% than those aged 55-64 years and Europeans.
One-third of patients were not adequately maintained on statins over the 3-year period following ACS, but 82% of those on a statin prior to admission had an MPR ≥80% over 3 years of follow-up. These findings define achievable treatment levels and identify groups who may benefit from efforts to improve statin use.