WASHINGTON — Hemoglobin A1c levels during ages 11–19 years correlated with the risk of complications as adults among type 1 diabetes patients diagnosed before age 10, Dr. Emily J. Gallagher reported at the annual scientific sessions of the American Diabetes Association.
Medical records were reviewed for 57 men and 72 women who ranged in age from 15 to 69 years and had been diagnosed with type 1 diabetes before age 10. The mean duration of diabetes was 28 years, said Dr. Gallagher, of University College in Dublin. Mean HbA1c values, available since 1983, were 7.5% for 30 of the patients at ages 0–10, rising to 9.4% for the 73 patients ages 11–19, then falling back to 8.5% after age 20 years in 108 patients.
Among the 129 study participants, 53% had developed at least one complication at a mean of 22 years after diagnosis. Retinopathy was present in 50% after a mean of 23 years, nephropathy in 23% after 28 years, and neuropathy in 18% after 27 years. Hypertension, HbA1c levels, and fasting triglycerides were significant predictors for the development of nephropathy, while A1c and hypertension predicted neuropathy.
For those with mean HbA1c levels below 8%, there was a 50% probability of any complication at 33 years after diagnosis. For those with mean HbA1c levels of 8%–10%, the time to a 50% probability of any complication was 26 years. For those with HbA1c values above 10%, the time was 16 years. HbA1c values during the 11- to 19-year age range correlated most strongly with time to development of complications, Dr. Gallagher reported.