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Health researchers have moved a step closer to predicting the future risk of heart attacks or strokes for people of Maori, Pacific Island or Indian ethnicity and those with a family history of problems.
Researchers in Auckland plan to analyse the data of more than 50,000 patients who have undergone a heart attack risk assessment with their GP.
A large number of GPs in Auckland use a software system called Predict which calculates a person's risk of having a heart attack or stroke over the next five years based on factors such as age, gender, and whether they smoke.
The calculation is based on models developed from studies of New Zealanders in the 60s and 70s.
"It's reasonably predictive for us New Zealanders as whole but the accuracy for Maori, Pacific and other high-risk population groups is unknown," said Dr Susan Wells, senior lecturer in clinical epidemiology at Auckland University. New Zealand guidelines recommend men over 45 and women over 55 get screened for their risks of heart attack or stroke.
But people of Maori, Pacific Island or Indian ethnicity, and those with a family history of heart disease, have higher risks, and are urged to start getting screened 10 years earlier.
The accuracy of the assessed risk for these groups, however, is not known.
But a study authored by Dr Wells and colleagues indicated that a five per cent upward adjustment for these groups may be accurate. The study appears in the latest Medical Journal.
Between 2002 and 2006, 23,709 patients in Auckland visiting their GP underwent cardiovascular risk assessment as part of opportunistic screening using Predict. Their baseline risk was calculated with and without a 5 per cent upward adjustment.
Dr Wells said the 5 per cent figure was an educated guess.
"It's looking like that adjustment factor for ethnicity is around about right. We're just in preliminary analysis, we're not certain yet."
The upward adjustment, however, meant that 20 per cent more people would need to be put on drugs, and be referred to a dietitian. Dr Wells said that while there was an additional cost, it would be better in the long run.
"Hopefully they won't then have a heart attack or stroke, and then of course you're lowering the cost not only for the health service, but also for society."
They now plan to look at a larger group of patients to better determine the additional risks of belonging in one of the three ethnic groups at higher risk, and those having a family history. They also plan to look at the long-term risks of someone developing heart disease over their lifetime.
"If we identify those people at high risk and manage them effectively we could reduce heart attacks and strokes in New Zealand by over 50 per cent."
