Descriptive analysis on sleep-disordered breathing in children with Prader-Willi syndrome

Purpose: Sleep-disordered breathing is one of the complicating characteristics in patients with Prader-Willi syndrome (PWS). No de-tailed description and risk factors are suggested on breathing problems during sleep in Korean children with PWS. Methods: We reviewed clinical and sleep-study data in patients with PWS who underwent polysomnography before they took the growth hormone therapy. Results: Of the 27 patients with PWS, 25 (92.6%) had sleep-disordered breathing, of whom 14 showed moderate to severe sleep apnea. Obstructive dominance was prevalent (64%), followed by central dominance (24%). The apnea-hypopnea index (AHI) increased with increasing weight-for-height z -score (WHZ) ( r =0.50, P =0.009), but did not differ by age. Apnea duration of over 12 months was longer in the patient group than in the infant group (15.1±4.3 seconds vs. 9.4±1.7 seconds, P =0.001) and in the obese than nonobese groups (16.8±4.3 seconds vs. 10.0±2.0 seconds, P =0.003). Desaturation below 70% was more common in the obese than nonobese subjects (3/9 vs. 0/18, P =0.029). Age was not different between the central and obstructive apnea groups, but patients with central apnea tended to be younger than patients with obstructive apnea (median [range]: 8.0 months [6.0–12.0 months] vs. 16.5 months [8.5–79.5 months], P =0.092). In addition, patients with obstructive apnea showed higher AHI (12.8 [5.9–19.2] vs. 3.9 [3.4–4.5], P =0.045). Conclusion: Sleep-disordered breathing is common in PWS children with different intensity and patterns according to age and BMI. Close monitoring of breathing problems during sleep is required in