Diabetes incidence has been climbing precipitously in the developed world along with rises in obesity rates and dietary and other lifestyle changes. But a massive new study finds that the rest of the global population has not been immune to these changes. Globally, the rate of diabetes has more than doubled in the past three decades.

For the new study, researchers analyzed the blood glucose levels of more than 2.7 million adults (25 years and older) in 199 countries. By their calculation, as of 2008 about 350 million people had diabetes, a disease that renders the body unable to properly control blood sugar levels and can lead to kidney failure and death. In 1980, that figure was closer to 153 million. The new work published online June 25 in The Lancet.

"Diabetes is one of the biggest causes of morbidity and mortality worldwide," Majid Ezzati, of the Center for Environment and Health at Imperial College in London and co-author of the new study, said in a prepared statement. The escalation of diabetes stands "in contrast to blood pressure and cholesterol, which have both fallen in many regions," he added. But "diabetes is much harder to prevent and treat." Not only is there no cure for diabetes, it is also a costly disease. In the U.S. alone, it eats up about $174 billion each year for the approximately 18 million people who have been diagnosed.

Much of the rise can be attributed to an aging population. But about 30 percent of the increase is likely due to other factors, such as lifestyle changes and obesity.

The biggest increases were in Pacific Island countries and Saudi Arabia, and the lowest overall rates were in sub-Saharan Africa. When averaged across countries, about 9.8 percent of men and 9.2 percent of women now have diabetes.

Martin Tobais, of the Health and Disability Intelligence department of the New Zealand Ministry of Health, calls the new findings stark, in an essay also published online in The Lancet. There is an "urgent need…to strengthen basic surveillance of dysglycaemia and diabetes," he noted. The disease often goes undiagnosed, even in countries such as the U.S., where medical care is typically more accessible than in the developing world. The American Diabetes Association estimates that more than a quarter of people with diabetes in the U.S. have not been diagnosed, which can lead to worse health outcomes.

Image: U.S. Department of Veterans Affairs