Diabetic Retinopathy and Other Complications of Childhood Type 1 Diabetes
Study Looks at Patients Diagnosed Pre-Puberty and at Puberty
In a multi-center study, researchers looked at infant and toddler type 1 diabetes. Specifically, they compared the impact the pre-pubertal duration of type 1 diabetes has on the occurrence of complications in 2 groups of patients who had had diabetes for the same number of years.
The research team published their findings in an article in the April 2012 edition of Diabetes Care. The article was called “Infant and toddler type 1 diabetes: complications after 20 years’ duration.”
A total of 105 patients were included in the study, and all participants were between 16 and 40.3 years old.
Participants were placed into a pre-pubertal at diagnosis group or a pubertal at diagnosis group. Out of the 105 patients, 53 were pre-pubertal (between 0 and 3 years old) when diagnosed with type 1 diabetes, and 52 were pubertal (between 9 and 14.9 years old—Tanner stage) at diagnosis. Patients in both groups had type 1 diabetes for the same number of years; mean duration of type 1 diabetes was 19.8 years for the pre-pubertal patients and 19.5 years for the pubertal patients.
All patients had retinal photographs taken and centrally graded. In addition to retinal photographs, the following were assessed:
- urinary albumin excretion (86 case subjects)
- blood pressure (89 case subjects)
- lifetime A1c levels (72 case subjects)
Researchers found that the prevalence of diabetic retinopathy (DR) was higher in the pubertal patients than in pre-pubertal patients. This was observed for any grade of DR (71% vs 40%; p=0.002) and for mild or more severe DR (p=0.005).
For that small group of patients who had moderate-to-severe DR, lifetime A1c levels (as percentages above the upper normal reference value) were higher (p<0.01) in the pre-pubertal group than in the pubertal group.
In addition, researchers did not find a difference between the 2 groups in regard to the prevalence of abnormal urinary albumin excretion.
Only 3 patients—all pubertal at diagnosis—had hypertension.
The researchers concluded that if type 1 diabetes is diagnosed in infants or toddlers (before age 3) and the pre-pubertal duration of diabetes is very long, then patients appear to be protected against diabetic retinopathy. However, if lifetime metabolic control is bad, this protection from diabetic retinopathy disappears. Researchers also concluded that when type 1 diabetes onset is at puberty, the DR risk is higher and less dependent on metabolic control in these patients. They noted that this may be influenced by blood pressure and other age-related factors.