Rates of diabetes have exploded in the past three decades, meaning an estimated 350 million people in the world now have the disease.

In almost every region of the planet diabetes prevalence has risen or at best remained unchanged, according to a major international study published in a special online report by The Lancet medical journal.

The condition, caused by poor blood sugar control, can lead to heart disease and stroke and can damage the kidneys, nerves and eyes. Each year, high blood sugar levels and diabetes kill three million people worldwide.

Increasing life span and body weight are two of the strongest factors influencing diabetes rates, especially among women, say researchers. But ethnic genetic factors, nutrition in the womb and soon after birth, quality of diet and physical activity are also thought to be important.

Scientists analysed blood sugar data on 2.7 million people aged 25 and over throughout the world and used the results to estimate diabetes prevalence. They found that the number of adults with diabetes more than doubled from 153 million in 1980 to 347 million in 2008, considerably higher than a 2009 estimate of 285 million.

Across the three decades, the proportion of men with diabetes rose by 18% from 8.3% to 9.8%. The proportion of women with diabetes increased even more sharply, from 7.5% to 9.2%, an increase of 23%.

Professor Majid Ezzati, from Imperial College London, who co-led the investigation, 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."

Between 85% and 95% of diabetes cases fall into the type 2 category, which is linked to lifestyle. Type 1, or insulin-dependent, diabetes is a separate auto-immune disorder and much less common.

The study showed that diabetes rates had risen most dramatically in Pacific island nations, where a greater proportion of people have the condition than anywhere else in the world. In the Marshall Islands, one in three women and one in four men have diabetes. Elevated blood glucose and diabetes prevalence was also high in southern Asia, Latin America, the Caribbean, central Asia, North Africa and the Middle East.

Among high-income countries, those of Western Europe had seen a relatively small increase in diabetes prevalence. Rates were highest in the US, Greenland, Malta, New Zealand and Spain and were lowest in The Netherlands, Austria and France.

Photo by TBPL, Press Assocation