Boston: The number of adults who have been diagnosed with diabetes worldwide has doubled to 347 million since 1980, with more than a third of them living in India and China, a new study has found.

According to the study by Harvard and World Health Organisation (WHO), the largest of its kind for diabetes, 70 per cent of the rise in worldwide diabetic cases was due to population growth and ageing, with the other 30 per cent due to higher prevalence.

Between 1980 and 2008, the number of adults with diabetes rose from 153 million to 347 million.

Of this number, 138 million live in China and India and another 36 million in the US and Russia, according to the study carried out by an international collaboration of researchers, led by Professor Majid  Ezzati from Imperial College London and co-led by Goodarz Danaei from the Harvard School of Public Health, in collaboration with The World Health Organisation.

"Our study has shown that diabetes is becoming more common almost everywhere in the world, in contrast to blood pressure and cholesterol, which have both fallen in many regions. Diabetes is much harder to prevent and treat than these other conditions," Ezzati said.

The proportion of adults with diabetes rose to 9.8 per cent of men and 9.2 per cent of women in 2008, compared with 8.3 per cent of men and 7.5 per cent of women in 1980. The estimated number of 347 million diabetics was considerably higher than a previous study in 2009 which put the number worldwide at 285 million.

The study included blood sugar measurements from 2.7 million participants aged 25 years or more across the world and used advanced statistical methods for analysing data. Funded by the Bill and Melinda Gates Foundation and WHO, the study also found that diabetes has taken off most dramatically in Pacific Island nations, which now have the highest diabetes levels in the world.

In the Marshall Islands, one in three women and one in four men have diabetes.

Glucose and diabetes were also particularly high in south Asia, Latin America, the Caribbean, Central Asia, North Africa and the Middle East.

Among high-income countries, the rise in diabetes was relatively small in Western Europe and highest in North America.

Diabetes and glucose levels were highest in USA, Greenland, Malta, New Zealand and Spain, and lowest in the Netherlands, Austria and France.

The region with the lowest glucose levels was sub-Saharan Africa, followed by east and southeast Asia.

350 million diabetics in world

Meanwhile, another international study published in a medical journal in London estimated 350 million people are suffering from diabetes worldwide.

Researchers from Imperial College London and Harvard University analysed data from 2.7 million people, aged 25 and over, across every continent, using statistical techniques to project a worldwide figure, to estimate diabetes prevalence.

They claim the total number of people with diabetes -- which can be fatal -- has risen from 153 million to 347 million in the past three decades, considerably higher than a 2009 estimate of 285 million.

Across the three decades, the proportion of men with diabetes rose by 18 per cent from 8.3 per cent to 9.8 percent. The proportion of women with diabetes increased even sharper, from 7.5 per cent to 9.2 per cent, an increase of 23 per cent, the study has revealed.

Prof Majid Ezzati of Imperial College London, the lead researcher, said: "Diabetes is one of the biggest causes of morbidity (illness) and mortality worldwide.

"Our study has shown that diabetes is becoming more common almost everywhere in the world. This is in contrast to blood pressure and cholesterol, which have both fallen in many regions. Diabetes is much harder to prevent and treat than these other conditions." In fact, every region of the planet has seen a rise in the disease prevalence, says the study which was carried out in conjunction with the World Health Organisation (WHO).

(Agencies)