Image caption Cheap generic versions of statin drugs are available

Most people around the globe with high cholesterol are not getting the treatment they need, claims the largest ever study of 147m people.

High levels of the blood fat are linked with cardiovascular disease, the world's biggest killer, which takes 17m lives a year.

The report in the Bulletin of the World Health Organization says too few people are put on cholesterol-lowering drugs.

The data, spanning a decade, is from England, Scotland and six more nations.

Between 1998 and 2007 information on cholesterol levels and prescribing patterns were gathered for England, Germany, Japan, Jordan, Mexico, Scotland, Thailand and the US.

Effective medication coverage for control of high cholesterol remains disappointingly low Dr Gregor Roth, Co-author of the WHO report

The analysis found many at-risk people in middle-income and western countries alike are not on cheap and widely available statin drugs that would substantially cut their risk of heart attack and stroke.

The report authors, which included Dr Gregory Roth from the Institute for Health Metrics and Evaluation in the US, say: "These findings support the growing recognition that cardiovascular diseases are not merely 'diseases of affluence' and that some middle-income countries are beginning to face a double burden of both chronic and communicable diseases."

Global issue

For example, in Thailand 78% of adults surveyed, who were found to have high cholesterol, had not been diagnosed, while in Japan, 53% of adults were diagnosed but remained untreated.

Although England fared slightly better, in 2006, when its snap-shot was undertaken, over two-thirds of people remained undiagnosed and around a fifth were diagnosed but untreated.

Mexico did the best, diagnosing and treating nearly 60% of cases.

Experts stress that things may have moved on since the data was gathered.

For example, England last year announced a mass programme where every person aged 40 to 74 would be offered a cholesterol check by the GP in a bid to reach those that had previously been missed.

But certainly there is still more progress that could be made on a global scale, says Dr Roth.

He said: "Cholesterol-lowering medication is widely available, highly effective and can play an essential role in reducing cardiovascular disease around the world.

"Despite these facts, effective medication coverage for control of high cholesterol remains disappointingly low."

Not all patients with high cholesterol will need drug treatment. Lifestyle measures like taking regular physical activity and eating a healthy diet, as well as giving up smoking, can help prevent heart disease and stroke.