Objectives To describe breathing patterns in infants with Prader-Willi Syndrome (PWS), as well as the effects of supplemental oxygen (O₂) on breathing patterns. Children with PWS commonly have sleep-disordered breathing, including hypersomnolence and obstructive sleep apnoea, as well as central sleep breathing abnormalities that are present from infancy.

Design Retrospective cohort study.

Patients Infants with a diagnosis of PWS.

Setting Tertiary children's hospital.

Interventions Infants with PWS underwent full polysomnography, and in those with frequent desaturations associated with central events, supplemental O₂ during sleep was started and followed with regular split-night studies (periods in both air and O₂).

Results Thirty split-night studies on 10 infants (8 female) aged 0.06–1.79 (median 0.68, IQR 0.45, 1.07) years were undertaken. At baseline (ie, air), children with PWS had a median (IQR) central apnoea index (CAI) of 4.7 (1.9, 10.6) per hour, with accompanying falls in oxygen saturation (SpO₂). O₂ therapy led to statistically significant reductions in CAI to 2.5/hour (p=0.002), as well as a reduced central event index (CEI) and improved SpO₂. No change in the number of obstructive events was noted. Central events were more prevalent in rapid-eye movement/active sleep.

Conclusions It is concluded that infants with PWS may have central sleep-disordered breathing, which, in some children, may cause frequent desaturations. Improvements in CAI and CEI as well as oxygenation were noted with O₂ therapy. Longitudinal work with this patient group would help to establish the timing of onset of obstructive symptoms.