Checks are urgently needed to find almost four million people who may be unaware that they are at high risk of heart disease, specialists have warned.
One in three adults who are most at risk of developing cardiovascular disease (CVD) over the next 10 years have not been diagnosed, a survey has found.
More than 71,000 people aged 18 and over were screened in 35 towns in Britain for the study. The findings showed that 75 per cent of men and 45 per cent of women over 50 already had CVD or diabetes, were taking cholesterol or blood pressure drugs or were at high risk of developing CVD.
Extrapolating the results to the whole country suggests that 7.9 million people have been diagnosed with heart disease or are at high risk of developing it but a further 2.8 million men and 900,000 women remain undiagnosed. The findings are published in the International Journal of Clinical Practice.
The researchers said that these people had not received the treatment and advice that could prevent them from developing the disease, and putting their lives at risk. The Government announced plans to roll out heart screening checks for people aged 40 to 74 earlier this year.
Andrew Neil, the professor of epidemiology who led the Oxford University team, said: "Our findings reinforce the need for a national cardiovascular risk assessment programme and we welcome the announcement by the Department of Health that plans are being put in place to institute primary care checks."
He said it was reassuring that 60 per cent of those at risk had been identified. "However, the challenge now is to identify the other 40 per cent."
Saranjit Sihota, Diabetes UK's head of public policy, said: "The findings of this new study, added to the fact that more than half a million people in the UK are unaware they have type 2 diabetes, highlights the urgency and importance of the Government's proposed screening programme.
"Some 80 per cent of people with diabetes die of heart disease so it's crucial this programme is rolled out quickly as early detection... could save the lives of thousands of people."
The National Institute for Clinical Excellence (Nice) said in May that more than one million adults at high risk of a heart attack were missing out on statins, cholesterol-lowering drugs proven to save lives.
In guidance to GPs it said that all adults aged 40 to 75 should be assessed and those with at least a 20 per cent increased risk of a heart attack over the next 10 years offered treatment.