Obstructive Sleep Apnea (OSA) in preadolescent girls is associated with delayed breast development compared to girls without OSA

Study Objective: Adults with obstructive sleep apnea (OSA) have lower sex steroid levels than controls. We sought to determine whether OSA also interferes with reproductive hormones in adolescence by tracking the pace of pubertal development. Methods: One hundred seventy-two children in the Tucson Children's Assessment of Sleep Apnea study (TuCASA) underwent two home polysomnographic studies, spaced 4-5 years apart. Height and weight were measured at both visits, and Tanner staging of breasts/genitals and pubic hair were self-assessed by a pictorial questionnaire at follow-up. Results: Eighty-seven girls and 85 boys, age 8.9 ± 1.6 years (mean ± SD) at baseline and 13.4 ± 1.6 years at follow-up, participated. Twenty-seven percent of participants were overweight or obese at baseline, and the majority remained so at follow-up. Twenty-six percent of girls and 28% of boys met criteria for OSA, defined as a respiratory disturbance index (RDI) ≥ 1/h associated with a 3% desaturation (RDI 3%), at baseline. There was an inverse relationship between baseline log RDI 3% and Tanner breast stage at follow-up (coefficient -1.3, p = 0.02) in girls after adjusting for age (p < 0.001), body mass index (p < 0.005), and ethnicity. Girls with OSA at baseline were more than 1 Tanner breast stage behind girls without OSA at follow-up. OSA did not affect genital development in boys or pubic hair development in either sex. Conclusions: OSA in preadolescent girls predicts delayed breast development relative to girls without OSA. Sleep fragmentation and/or hypoxia seen in OSA may interfere with reproductive development in girls.