June 27, 2011 (San Diego) -- The life expectancy for people with childhood-onset type 1 diabetes has improved dramatically since 1950, according to results of a 30-year study. And the survival gap between people with type 1 diabetes and the general population in the U.S. appears to be rapidly diminishing, the study found.
"While type 1 diabetes mortality rates have decreased over time, how this translates into improvements in life expectancy has been unclear," says Trevor J. Orchard, MD, professor of epidemiology, pediatrics, and medicine at the University of Pittsburgh.
So Orchard and colleagues examined data from the Pittsburgh Epidemiology of Diabetes Complication study, a long-term study of childhood-onset type 1 diabetes.
They compared two groups based on year of diabetes diagnosis: 390 people diagnosed between 1950 and 1964 and 543 people diagnosed between 1965 and 1980.
People diagnosed with diabetes between 1965 and 1980 lived approximately 15 years longer than those diagnosed between 1950 and 1964 (53.4 years vs. 68.8 years).
The estimated 15-year life expectancy improvement between the two groups persisted regardless of gender or age at diagnosis, Orchard says.
Meanwhile, the life expectancy of the general U.S. population increased less than one year during the same time period.
The life expectancy of a population as a whole tends to change slowly, while that of a group with a particular condition or illness may improve rapidly from advances in screening and treatment.
Orchard attributes the increase in life expectancy among people with type 1 diabetes to a combination of factors, most notably improvements in treating diabetes-associated kidney disease and better blood glucose testing that allows more people to be diagnosed earlier.
Robert Henry, MD, president of medicine and science for the American Diabetes Association (ADA), tells WebMD that he credits better technology, such as insulin pumps that allow patients to achieve better control of their blood sugar.
Other findings of the study, presented here at the 71st Scientific Sessions of the ADA:
The life expectancy of people diagnosed in the earlier time period was about 18 years less than that estimated for the U.S. general population at that time (71.5 years).
In contrast, there was only a four-year gap in life expectancy between people diagnosed in the latter time period and the U.S. general population (72.4 years at that time).
The 30-year mortality rate of participants diagnosed with type 1 diabetes from 1965 to 1980 was 11.6% -- a significant decline from the 35.6% 30-year mortality of people diagnosed between 1950 and 1964.