Corina Grey

Cohort Profile: The PREDICT Cardiovascular Disease Cohort in New Zealand Primary Care (PREDICT-CVD 19)

Cohort Profile: The PREDICT Cardiovascular Disease Cohort in New Zealand Primary Care (PREDICT-CVD 19) Sue Wells,* Tania Riddell, Andrew Kerr, Romana Pylypchuk, Carol Chelimo, Roger Marshall, Daniel J. Exeter, Suneela Mehta, Jeff Harrison, Cam Kyle, Corina Grey, Patricia Metcalf, Jim Warren, Tim Kenealy, Paul L. Drury, Matire Harwood, Dale Bramley, Geeta Gala and Rod Jackson School of Population Health, University of Auckland, Auckland, New Zealand, Middlemore Hospital, Cardiology Department, Auckland, New Zealand, School of Pharmacy, University of Auckland, Auckland, New Zealand, Endocrinology Services, Auckland District Health Board, Auckland, New Zealand, Computer Sciences, University of Auckland, School of Medicine, University of Auckland, Auckland, New Zealand, Waitemata District Health Board, Auckland, New Zealand and Northern Regional Alliance, Auckland, New Zealand

Twenty‐eight day and one‐year case fatality after hospitalisation with an acute coronary syndrome: a nationwide data linkage study

Objectives: To determine 28‐day and one‐year case fatality in patients hospitalised with acute coronary syndromes (ACS) and identify factors associated with mortality.

Initiation and maintenance of cardiovascular medications following cardiovascular risk assessment in a large primary care cohort: PREDICT CVD-16.

Aim: To examine whether use of a standardized cardiovascular disease (CVD) risk assessment recommended by national guidelines is associated with appropriate initiation and maintenance of medication in a large primary care cohort. Methods and design: A total of 90,631 people aged 30−80 years were followed for up to 3 years after a formal CVD risk assessment was undertaken between January 2006 and October 2009, during routine primary care visits in New Zealand. Patients either had prior CVD or had their CVD risk estimated using a modified Framingham prediction equation for fatal or non-fatal CVD events. The individual risk profiles were anonymously linked to national dispensing data for blood-pressure-lowering and lipid-lowering medications in the 6-month period before and in consecutive 6-month blocks after the baseline CVD risk assessment. Results: At baseline, a combination of blood-pressure-lowering and lipid-lowering therapy was already being used by about two-thirds of patients with prior CVD, one-quarter with a 5-year CVD risk greater than 10% (approximately 20% 10-year risk), and one-tenth with CVD risk below this level. Among these previously treated patients, dispensing rates for blood-pressure-lowering, lipid-lowering, or both medications together declined by only 4⊟16% up to 3 years after baseline assessment, irrespective of risk category. Among patients untreated at baseline, combination therapy was initiated within 6 months for 21% with prior CVD, 16% with 5-year CVD risk greater than 15% (approximately 30% 10-year risk and the national drug-treatment threshold), 10% with 5-year CVD risk between 10 and 14% (approximately 20⊟29% 10-year risk), and 3% in the lowest risk category. Across the study population, patients with prior CVD had the highest dispensing rates for each category of medication, and incrementally higher dispensing rates were noted as CVD risk group increased. Conclusions: In this primary care cohort, most patients already using CVD medications at the time of the baseline CVD risk assessment maintained treatment over a maximum of 3 years follow up, irrespective of their estimated baseline risk. Among patients untreated at baseline, subsequent dispensing rates were strongly related to estimated CVD risk group. Around 15⊟20% of untreated patients meeting national drug-treatment criteria commenced combination pharmacotherapy within 6 months of CVD risk assessment.

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 24–25% (broad and narrow balanced) to 37–39% (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.

Maintenance of statin use over 3 years following acute coronary syndromes: a national data linkage study (ANZACS-QI-2)

Objective To describe patterns of statin use and predictors of poor maintenance over a 3-year period following an acute coronary syndrome (ACS). Methods 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%. Results 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. Conclusions 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.

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

Objectives To examine recent trends in first and recurrent ischaemic heart disease (IHD) deaths and hospitalisations. Methods Using anonymous patient-linkage of routinely collected data, all New Zealanders aged 35–84 years who experienced an International Statistical Classification of Diseases and Related Health Problems I(CD)-coded IHD hospitalisation and/or IHD death between 1 January 2005 and 31 December 2015 were identified. A 10-year look-back period was used to differentiate those experiencing first from recurrent events. Age-standardised hospitalisation and mortality rates were calculated for each calendar year and trends compared by sex and age. Results 160 109 people experienced at least one IHD event (259 678 hospitalisations and 35 548 deaths) over the 11-year study period, and there was a steady decline in numbers (from almost 24 000 in 2005 to just over 16 000 in 2015) and in age-standardised rates each year. With the exception of deaths in younger (35–64 years) women with prior IHD, there was a significant decline in IHD events in men and women of all ages, with and without a history of IHD. The decline in IHD mortality was greater for those experiencing a first rather than recurrent IHD event (3.8%–5.2% vs 0%–3.7% annually on average). In contrast, the decline in IHD hospitalisations was greater for those experiencing a recurrent compared with a first IHD event (5.6%–7.3% vs 3.2%–5.7% annually on average). Conclusions The substantial decline in IHD hospitalisations and mortality observed in New Zealanders with and without prior IHD between 2005 and 2015 suggests that primary and secondary prevention efforts have been effective in reducing the occurrence of IHD events.

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 Māori, 4% Pacific, 3% Indian and 83% New Zealand European or Other ethnicities (NZEO). A larger proportion of Māori (48%) than NZEO (36%), Pacific (19%) and Indian (14%) patients were admitted to hospitals without catheterisation facilities. More Māori and Pacific (22-24%) than NZEO and Indian patients (12-13%) had severe comorbidities. Māori 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 Māori and Pacific patients and reduced access to catheterisation facilities for non-urban Māori contributed to lower procedure rates after ACS admission. Ethnic differences remained after adjustment for these factors and require further investigation.

Initiation and maintenance of statins and aspirin after acute coronary syndromes (ANZACS-QI 11)

INTRODUCTION Prior New Zealand studies suggest that only approximately two-thirds of patients who present with an acute coronary syndrome (ACS) are maintained on a statin/aspirin post-discharge. This could be due to sub-optimal initiation or poor longer-term adherence. AIM To identify the pattern of statin/aspirin maintenance following ACS from initial prescription to 3 years post-discharge. METHODS All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry data for consecutive New Zealand residents (2007-2011), who were hospitalised with ACS, were anonymously linked to national datasets to derive a medication possession ratio (MPR) to assess medication maintenance. An MPR ≥ 0.8 is considered adequate maintenance. RESULTS Of the 1846 patients discharged alive, 95% were prescribed a statin at discharge and 92% were dispensed a statin within 3 months, but only 75% had a MPR ≥ 0.8 in the first year, and 67% in year 3. In the same cohort, 98% were prescribed aspirin and 88% were dispensed aspirin within the 3 months of discharge. In the first year, 72% had an aspirin MPR ≥ 0.8 and 71% maintained this in year 3. Fifty-nine percent were maintained on both aspirin and a statin in the third year, but 20% were maintained on neither. Regression analysis identified the independent predictors of inadequate maintenance in the third year as age < 45 years, no prior statin, and Māori and Pacific ethnicity. CONCLUSION Longer-term maintenance of evidenced-based secondary prevention medications after ACS is suboptimal despite high levels of initial prescribing and dispensing. Understanding the barriers to longer-term maintenance is required to improve patient outcomes.

Ethnic differences in case fatality following an acute ischaemic heart disease event in New Zealand: ANZACS-QI 13

Background The aim of this study was to investigate ischaemic heart disease (IHD) case fatality in high-risk ethnic populations in New Zealand. Design This is a national data-linkage study using anonymised hospitalisation and mortality data. Methods Linked individual patient data were used to identify 35–84-year-olds who experienced IHD events (acute IHD hospitalisations and/or deaths) in 2009–2010. Subjects were classified as: (i) hospitalised with IHD and alive at 28 days post-event; (ii) hospitalised with IHD and died within 28 days; (iii) hospitalised with a non-IHD diagnosis and died from IHD within 28 days; or (iv) died from IHD but not hospitalised. Multinomial logistic regression was used to estimate the proportion of people in each group, as well as overall 28-day case fatality, adjusted for ethnic differences in demographic and comorbidity profiles. Results A total of 26,885 people experienced IHD events (11.3% Māori, 4.0% Pacific and 2.5% Indian); 3.3% of people died within 28 days of IHD hospitalisations, 5.1% died of IHD within 28 days of non-IHD hospitalisations and 13.0% died of IHD without any recent hospitalisation. Overall adjusted case fatality was 12.6% in Indian, 20.5% in European, 26.0% in Pacific and 27.6% in Māori people. Compared to Europeans, the adjusted odds of death were approximately 50% higher in Māori and Pacific people and 50% lower in Indians, regardless of whether they were hospitalised. Conclusions Major ethnic inequalities in IHD case fatality occur with and without associated hospitalisations. Improvements in both primary prevention and hospital care will be required to reduce inequalities.

Using integrated visualization techniques to investigate associations between cardiovascular health outcomes and residential migration in Auckland, New Zealand

The negative health effects of living in a deprived neighborhood may influence the incidence of cardiovascular disease (CVD), even after controlling for sociodemographic characteristics, and there is evidence that residential mobility is associated with mortality and morbidity rates. However, few studies have investigated the application of integrated visualization techniques and statistic modeling to communicate the association between residential mobility and cardiovascular outcomes. We focus on examining the association between cardiovascular health outcomes and patient migration in Auckland, New Zealand, in two ways. First, we assess the association between all-cause mortality among patients with CVD and deprivation mobility, controlling for age, gender and ethnicity using multiple logistic regression at the individual level, and then visualize the results. Second, we identify aggregated geographical patterns of prevalence of CVD stratified using migration status, area-deprivation, ethnicity, and geographical area using kriskograms, ring-cartograms, and ringmaps to visualize the results. We reveal distinct patterns for purposefully selected subgroups and highlight disparities by geographic area, deprivation, and ethnicity before discussing the implications of our findings in relation to migration and health outcomes.