Using Kisspeptin to Predict Pubertal Outcomes for Youth With Pubertal Delay.

CONTEXT: The management of youth with delayed puberty is hampered by difficulty in predicting who will eventually progress through puberty and who will fail to attain adult reproductive endocrine function. The neuropeptide kisspeptin, which stimulates gonadotropin-releasing hormone (GnRH) release, can be used to probe the integrity of the reproductive endocrine axis. OBJECTIVE: We sought to determine whether responses to kisspeptin can predict outcomes for individuals with pubertal delay. DESIGN, SETTING, AND PARTICIPANTS: We conducted a longitudinal cohort study in an academic medical center of 16 children (3 girls and 13 boys) with delayed or stalled puberty. INTERVENTION AND OUTCOME MEASURES: Children who had undergone kisspeptin- and GnRH-stimulation tests were followed every 6 months for clinical evidence of progression through puberty. Inhibin B was measured in boys. A subset of participants underwent exome sequencing. RESULTS: All participants who had responded to kisspeptin with a rise in luteinizing hormone (LH) of 0.8 mIU/mL or greater subsequently progressed through puberty (n = 8). In contrast, all participants who had exhibited LH responses to kisspeptin ≤ 0.4 mIU/mL reached age 18 years without developing physical signs of puberty (n = 8). Thus, responses to kisspeptin accurately predicted later pubertal outcomes (P = .0002). Moreover, the kisspeptin-stimulation test outperformed GnRH-stimulated LH, inhibin B, and genetic testing in predicting pubertal outcomes. CONCLUSION: The kisspeptin-stimulation can assess future reproductive endocrine potential in prepubertal children and is a promising novel tool for predicting pubertal outcomes for children with delayed puberty.

Disordered eating behaviors in youth with type 1 diabetes: prospective pilot assessment following initiation of insulin pump therapy.

BACKGROUND: There is risk for disordered eating behaviors in type 1 diabetes, especially related to insulin manipulation. Implementation of insulin pump therapy may encourage either normalization of eating behaviors or a greater focus on food intake due to renewed emphasis on carbohydrate counting. There is need for prospective studies to assess disordered eating behaviors upon implementation of pump therapy using diabetes-specific measurement tools. SUBJECTS AND METHODS: In a multicenter pilot study, 43 youth with type 1 diabetes, 10-17 years old, were assessed prior to pump initiation and after 1 and 6 months of pump therapy. Youth completed the Diabetes-specific Eating Problems Survey-Revised (DEPS-R), a validated measure of risk for both diabetes-specific and general disordered eating behaviors. RESULTS: Youth (45% female), 13.3 years old with diabetes for 2.1 years, had a mean hemoglobin A1c of 8.3±1.3% (68±14.5 mmol/mol) at baseline. DEPS-R scores decreased over time (P=0.01). Overall rate of high risk for eating disorders was low. Overweight/obese youth endorsed more disordered eating behaviors than normal-weight participants. DEPS-R scores were correlated with z-score for body mass index at all three time points and with hemoglobin A1c after 1 and 6 months. Hemoglobin A1c did not change significantly over the 6 months and was higher in overweight/obese compared with normal-weight participants. CONCLUSIONS: Initiation of insulin pump therapy was associated with diminished endorsement of disordered eating behaviors in youth with type 1 diabetes. Longer follow-up studies are needed to assess the impact of insulin pump therapy on glycemic control, weight status, and disordered eating behaviors in this vulnerable population.