A PIONEERING new study is set to test the theory that type 1 diabetes is triggered by lifestyle and environmental stresses by trialling whether an existing drug treatment can prevent the condition from ever developing among high-risk individuals.

There are around 6,400 families in Scotland affected by type 1 diabetes. The clinical evaluation aims to tracks down all Scottish children aged five to 16 who have a sibling or parent with the condition and invite them to undergo a blood test to discover whether they are genetically predisposed to developing it.

If so, they will be invited to participate in the trial.

The results could help to explain why rates of type 1 diabetes have increased five-fold in the past 40 years. Scotland has been chosen as the launchpad for the trial because it has the third highest incidence of type 1 diabetes in the world.

The study, a join initiative between the Universities of Exeter and Dundee, will test the theory that the trigger for type 1 diabetes is rooted in many of the same modern stresses associated with the type 2 version, such as obesity, a sedentary lifestyle, excessive alcohol consumption, smoking and air pollution.

In type 1 diabetes, patients are unable to make insulin because the cells in their pancreas responsible for producing the hormone are too damaged. As a result, their body is unable to regulate blood-sugar levels naturally and, without regular insulin injections, the glucose in their bloodstream would become toxic.

Previously scientists believed type 1 diabetes was an autoimmune disorder caused by a faulty immune system which attacks and destroys insulin-producing beta cells in the pancreas.

However, this has been called into question by disappointing results from clinical trials testing drugs that suppress the immune system.

The new Scottish study will turn the theory on its head by investigating whether it is lifestyle and environmental stresses that first damage the beta cells, and that once damaged these cells transmit signals triggering the immune system to attack them.

The theory, known as the 'accelerator hypothesis', was first put forward in 2001 by Exeter University academic, Professor Terence Wilkin, who will lead the study.

If correct, high-risk individuals should be able to prevent the onset of type 1 diabetes by taking metformin - a common and inexpensive diabetes drug known to protect the beta cells from stress.

Prof Wilkin said: “It is possible that a modern environment accelerates the loss of beta cells by overworking and stressing them.

“If successful, the trial will offer a means of preventing type 1 diabetes with a cost-effective medication, and could be made immediately available to children at risk.”

The adAPT study, based out of Ninewells Hospital in Dundee, will initially split participants into metformin and placebo groups for four months.

The study will gradually be expanded to include all the health boards in Scotland and extended to England.

Co-researcher Professor Stephen Greene, a specialist in child and adolescent health at Ninewells and director of the Scottish Children’s Research Network, said the findings could be "extremely important".

He said: "A simple, safe and effective drug that would prevent the development of type 1 diabetes in young people would be a major breakthrough.”