The number of adults with diabetes worldwide has more than doubled since 1980, with almost 350 million now affected, according to a new study published in The Lancet medical journal.

Scientists from Imperial College London and Harvard University analysed blood sugar date of 2.7 million people aged 25 and over across the world and used the results to estimate diabetes prevalence.

The number of adults with diabetes more than doubled from 153 million in 1980 to 347 million in 2008, according to the research published Saturday.

Diabetes is caused by poor blood sugar control and can lead to heart disease and stroke and can damage the kidneys, nerves and eyes.

High blood sugar levels and diabetes kill three million people across the world each year.

The researchers said two of the strongest factors in the rising diabetes rate were increasing life span and body weight, especially among women.

"Our study has shown that diabetes is becoming more common almost everywhere in the world," said Majid Ezzati, from Imperial College London, who co-led the study.

"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."

Diabetes rates had risen most in Pacific island nations, where a greater proportion of people have the condition than anywhere else in the world, according to the study.

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

Countries in western Europe had seen a relatively small increase in diabetes prevalence.