PATIENTS suffering from diabetes are living longer lives, a study in Scotland has revealed.

Previous research has suggested that patients with type one diabetes can expect to die 15 to 20 years earlier than those without the condition.

A major investigation carried out by a team from Dundee University and the Scottish Diabetes Research Network found this is no longer the case - but type one diabetics still have a shorter life expectancy.

The research, which was published in the Journal of the American Medical Association yesterday(tue) evening, found type one diabetes is associated with an average reduction in life expectancy of about 11 years in men and about 13 years in women, compared with the general Scottish population.

Professor Helen Colhoun, of Dundee University, stressed these figures represent an average and some people - with well controlled diabetes - will live longer while some people with more problems will die when they are quite young.

She continued: "The over all trend is one of improvement, but the other key message is there is still some way to go. We really should have a go at reaching zero loss of life expectancy. This throws down the gauntlet to us and highlights just how far there is to go to achieve that aim."

Very few people have systematically evaluated the impact of type one diabetes on life expectancy, according to Professor Colhoun.

Diabetes charities such as Diabetes UK and the Juvenile Diabetes Research Foundation cite losses of life expectancy of between 15 and 20 years, while estimates from the United States in the 1970s reported a loss of 27 years.

Major advances in the treatment of type one diabetes have occurred in recent decades and the Dundee study used a large national registry of patients with type one diabetes living in Scotland to up-date the picture.

They found in the general population, 76 per cent of men and 83 per cent of women survived to the age of 70 compared with 47 per cent of men and 55 per cent of women with type one diabetes.

The researchers also reported that at the age of 20, men with type one diabetes could expect to live another 46.2 years, and men without it an extra 57.3 years - a difference of just over 11 years. For women the gap was 12.9 years.

Professor Colhoun said the medical profession had a much better understanding of the importance of managing blood sugar levels today, but achieving good control for all patients was difficult.

There has been recognition, she said, on the clinical side that patients need to be assisted to better manage their own condition day to day and self management eduction is key to good treatment.

However, she added: "There is still some way to go to have everyone engaged with that and not everyone has been given access to it."

She also said too many people are diagnosed with kidney problems including advanced kidney disease. "We really need a lot more research to understand and to see if there is any other way we can tackle that and prevent that occurring," she said.

Sarah Ward, deputy national director of Diabetes Scotland, said: "This large study adds to our understanding of the serious impact of type one diabetes on length of life. The suggested increase in life expectancy is likely due to the improvements we have seen in diabetes care over the last 20 to 30 years, such as home blood glucose testing, earlier detection of diabetes and management of complications of the condition.

"While this report is encouraging, much more work remains to ensure better routine care for people with type one diabetes to enable them to manage their condition and live longer, healthier lives."