A new score for predicting an individual’s risk of heart disease performs better than the existing test and should be recommended by the National Institute for Health and Clinical Excellence (NICE), say researchers in a paper published on bmj.com yesterday.
NICE currently recommends that doctors use a modified version of the long-established Anderson Framingham risk score to identify who should be offered statin treatment to reduce their risk of heart disease over the next 10 years, but in 2007, the British Medical Journal (BMJ) published research showing that the new score, known as QRISK and specifically developed for use in the UK, was a more accurate measure of how many UK adults are at risk of developing heart disease and are most likely to benefit from treatment compared with the Framingham model. The research underpinning QRISK was also published in the journal Heart in January 2008.
Now, two independent experts from the University of Oxford have compared the performance of the two scores for predicting the 10-year cardiovascular disease risk in 1.07 million patients in England and Wales, all aged 35-74 as the study began, tracking them for up to 12 years after first diagnosis of cardiovascular disease.
The study, which was funded by the Department of Health, found that, on every performance measure, QRISK gave a more accurate prediction of 10-year cardiovascular disease risk compared with Framingham. _For example, the rate of cardiovascular disease events among men was 30.5 per 1,000 person years in high-risk patients identified with QRISK and 23.7 per 1,000 person years in high-risk patients identified with Framingham. Similarly, the rate of cardiovascular disease events among women was 26.7 per 1,000 person years in high-risk patients identified with QRISK compared with 22.2 per 1,000 person years in such patients identified with Framingham.__
In other words, they say, QRISK identified a group of high-risk patients who will go on to experience more cardiovascular events over the next 10 years more accurately than a similar group identified by Framingham. This finding is probably not surprising, they add, as QRISK was developed on a separate but equally large cohort of patients in the UK and is thus more tailored to the UK population. Furthermore, QRISK contains additional risk factors - social deprivation, body mass index, family history and current treatment with blood pressure drugs - which are known to affect cardiovascular disease risk and that are not included in either of the Framingham equations.__
“We have assessed the performance of QRISK against the current NICE recommended model and have provided evidence to support the use of QRISK in favour of the Anderson Framingham equation,” the study authors conclude.
In an accompanying editorial, researchers from the University of Auckland, New Zealand, also support the use of QRISK over Anderson Framingham, but point out that QRISK is just the first of many continuously-updateable prediction algorithms that will become available as electronic health records replace current paper-based systems. They also note that there are concerns regarding commercial restrictions to the use of the algorithm, and suggest that freely sharing these data is more likely to facilitate their effective implementation.__