Mechanism Behind Pubertal Insulin Resistance Revealed
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WESTPORT, CT (Reuters Health) Dec 07 - The phenomenon of pubertal insulin resistance is well documented, but the mechanism has largely been unknown. Results of a longitudinal study suggest a blunted beta-cell response to compensatory changes in insulin sensitivity is involved.

Dr. Michael I. Goran of the Institute for Prevention Research at the University of Southern California, Los Angeles and a colleague followed 60 white and African-American children for roughly 2 years. All were at Tanner stage I at baseline. At the end of follow-up, 31 of the children had progressed to Tanner stage III or IV.

Tanner stage progression was associated with a significant 32% drop in insulin sensitivity, a "disproportionately low" 30% increase in the acute insulin response and a significant 27% fall in the disposition index. Increases in fasting glucose and insulin were also observed in children progressing in Tanner stage. These changes were similar regardless of sex, ethnicity or weight and were not evident in children remaining at Tanner stage I.

These findings, the authors say, suggest that "a conservation in beta-cell function or an inadequate beta-cell response" to the fall in insulin sensitivity may play a role in pubertal insulin resistance.

The marked drop in insulin sensitivity was not related to changes in body or visceral fat, circulating hormone levels or insulin growth factor-I.

"The clinical implications are that overweight children who are going through puberty have an increased risk for developing diabetes, especially if they have a positive family history of type-2 diabetes and are...Hispanic, African American or Native American," Dr. Goran told Reuters Health.

"These at-risk children should be checked regularly for diabetes, using fasting glucose or other tests, and should be encouraged to participate in lifestyle interventions to improve diet, increase physical activity and lose weight before and during puberty," he said.

Diabetes 2001;50:2444-2450.

from: primarycare.Medscape.com