Many heart attack patients do not use recommended medications

A large proportion of people who suffer from heart attacks and strokes in Australia do not use the recommended medications when they leave hospital, according to new analysis by the Australian Institute of Health and Welfare (AIHW). Around 24,800 Australians died from coronary heart disease or stroke in 2020 (out of 161,300 deaths from all causes in 2020).

The AIHW released two reports with insights into patient pathways following chronic heart disease (CHD) hospitalisations and improved estimates of the number of people who suffer heart attacks and strokes.

“Every day in 2018, about 110 Australians had a heart attack for the first time and 79 had a stroke. Of these, 17 of the people who had heart attacks and 21 of the people who had strokes died,” said AIHW spokesperson Miriam Lum On.

One report — Medication use for secondary prevention after coronary heart disease hospitalisations: patient pathways using linked data — uses data from the National Integrated Health Services Information Analysis Asset* (NIHSI AA).

The study examined 67,800 people who had been admitted to hospital with CHD between 1 July 2016 and 30 June 2017. About half (35,200) of these people had acute coronary syndrome (ACS), which includes heart attacks and unstable angina.

“Australian clinical guidelines recommend that people who survive an ACS event are prescribed a multidrug regime that includes four medication classes,” Lum On said.

Only 61% of people with ACS had been dispensed three or more of the guideline-recommended preventive medicines within 40 days of leaving hospital. This was less common in women and people who underwent a bypass graft during their hospitalisation.

Lum On said the data provides a better understanding of some of the factors that affect medication use by people with CHD discharged from hospital. However, further work is required to identify why some population subgroups were less likely to access preventive medications, or continue medications after hospitalisation.

“The AIHW is working with closely with our expert advisory group on further analysis examining the relationship between medication adherence and the risk of subsequent hospitalisations and death,” Lum On said.

The second report — Estimating the incidence of stroke and acute coronary syndrome using the National Integrated Health Services Information Analysis Asset* — uses linked data to improve the accuracy of stroke and ACS event estimates.

Almost 29,000 Australians had a stroke and 40,200 had an ACS event for the first time in 2018.

“Stroke occurs when a blood vessel supplying blood to the brain either suddenly becomes blocked (ischaemic stroke) or ruptures and begins to bleed (haemorrhagic stroke). It can cause severe cognitive impairment and is often fatal,” Lum On said.

“Data available from 2011 to 2018 shows the rate of new and repeat strokes estimated from the linked data remained fairly stable, between 150 and 153 per 100,000 population.

“After adjusting for age differences, the rate of new strokes was higher in males than females in 2018. Stroke also increased with age, with the rate of the 85 and over age group (1700 per 100,000 population) more than five times the rate of the 65–74 age group (308 per 100,000 population).”

The rate of people with new and repeat ACS events estimated from the linked data fell from 472 to 337 per 100,000 population between 2011 and 2018.

“Monitoring the incidence of stroke and ACS is crucial for assessing the health and economic burden of these conditions on Australians, health service planning and evaluating progress in prevention and management,” Lum On said.

There is no direct way to count the number of new stroke or ACS events at the national level, but the new reports aim to fill the gap by using linked data to estimate and differentiate between new and recurring events occurring in people more accurately, Lum On said.

^{*The National Integrated Health Services Information Analysis Asset (NIHSI AA)
Both reports use the NIHSI AA, which links deidentified data from hospital admissions, emergency department presentations, residential aged care, the National Death Index and services provided under the Medicare Benefits Schedule and prescriptions supplied under the Pharmaceutical Benefits Scheme and Repatriation Pharmaceutical Benefits Scheme.}

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