Bright Side to Diabetes Increase

Prevalence of type 1 diabetes has risen in many parts of the world. In one way, that may be a good thing. It could mean that people with diabetes are living longer.

Researchers in Australia researchers wanted to understand why the rise in type 1 diabetes cases is spread unevenly across the globe. What they found is that it may be directly linked to advances in medical care.

To better understand the trends, researchers from the University of Adelaide School of Medicine’s Biological Anthropology and Comparative Anatomy Research Unit in Adelaide, Australia, measured the prevalence of type 1 diabetes in 118 countries as well as changes in life expectancy between 1950 and 2010. What they found was a rapid increase in type 1 diabetes prevalence in the last few decades that directly linked to a rise in life expectancy, particularly in Western countries.

"Up to the early 20th century, type 1 diabetes was a horrible and dangerous disease, usually leading to people's death during their teens or early 20s," says lead author Wenpeng You, a PhD candidate in the Unit. "However, with the widespread introduction of insulin from the 1920s onwards, and improvements in modern medicine, life expectancy for people with type 1 diabetes has now increased to about 69 years.”

People with type 1 diabetes are more likely to live on and have families, and thus pass along the genes that underlie type 1 diabetes. However, countries without good health care provision or easy access to insulin haven’t benefited from that leap in life expectancy, so they are less likely to pass on genes for diabetes.

"This is the first major disease we have shown that is accumulating due to a relaxation of natural selection over time. It's unlikely this situation will ever be reversed, meaning that in order to overcome the problems associated with type 1 diabetes for our population, some form of gene therapy to repair the faulty genes may need to be considered," said Maciej Henneberg, PhD, DSc, who heads the Unit.

The study was published online on March 2 in BMJ Open Diabetes Research & Care.