By Martha Kerr

NEW YORK (Reuters Health) Jun 24 - Sex hormone-binding globulin (SHBG) and total testosterone levels are elevated in boys and young men with childhood-onset diabetes, investigators report in the June issue of Diabetes Care.

The findings come from a study of 48 patients with diabetes diagnosed at age 18 years or younger and 47 siblings without diabetes enrolled in the Chicago Childhood Diabetes Registry Family Study.

The age range was 10-32 years. Classic type 1 diabetes was present in 75% of the proband, while the remaining 25% had features of type 2 or mixed diabetes. Overall, 96% were treated with insulin.

The researchers measured SHBG and total and free testosterone levels in the subjects and found that levels of the hormones were higher in male subjects with diabetes than in their male siblings.

"Elevated SHBG was associated with the absence of endogenous insulin, independent of sex; elevated total testosterone was similarly associated with the absence of C-peptide for male subjects only," the authors report. "Diabetes type and treatment were unrelated (to hormone levels)."

Lead author Dr. Kirstie K. Danielson of the University of Chicago, Illinois explained in an interview with Reuters Health," The elevations in testosterone and SHBG in males with childhood-onset diabetes were more strongly associated with their long-term lack of endogenous insulin production than with short-term modifiable factors such as glycemic control and intensity of treatment."

"It is therefore possible that these alterations in sex hormones are not modifiable and may only be avoided by preventing diabetes in children," she said. "However, it remains unknown whether the magnitude of these alterations have long-term clinical significance and should be modified if they could. Further research is clearly needed."

Diabetes Care 2008;31:1207-1213.