Study Indicates Sleep Apnea in Infants with Prader-Willi Syndrome Occurs Before Growth Hormone Therapy

Researchers note that these vulnerable infants often struggle to wake up or respond to breathing distress, thus potentially facing a heightened risk of sudden death from respiratory complications. The study underscores the necessity for personalized sleep monitoring strategies to safeguard these infants.

The researchers emphasized the complexity of early respiratory manifestations in PWS, noting that their origins are likely multifactorial and not fully understood. They indicated that because infants with PWS may have impaired arousal responses, individualized monitoring—comprising polysomnography (PSG) and selective home monitoring—is essential to mitigate respiratory risks.

The study, titled “Polysomnographic findings and brain maturation in infants with Prader-Willi syndrome: a retrospective observational study,” was published in the journal *Sleep and Breathing*. PWS is a genetic disorder that can manifest with a variety of symptoms, including slow growth, low muscle tone, and behavioral challenges. Notably, it also affects parts of the brain that control sleep and breathing, leading to possible central sleep apnea and sleep-related hypoventilation.

Growth hormone therapy is often administered to children with PWS, as many have low levels of growth hormone, which is pivotal for physical development. While there have been concerns regarding an increased risk of OSA due to treatment, particularly from tonsil and adenoid enlargement, evidence supporting this link remains limited.

In the Belgian study, researchers reviewed data from seven infants diagnosed with PWS between February 1965 and December 2023. Six of these infants underwent PSG, while one newborn only had a sleep electroencephalography (EEG) before dying suddenly. Notably, all tests were performed prior to starting growth hormone therapy. None of the infants who had PSG showed clinically significant central sleep apnea.

Clinically relevant OSA was identified in four of the six infants (66.6%), with half classified as mild and the other half as moderate. Paradoxical breathing was observed in two infants, although this was more pronounced in newborns without significant statistical divergence. The infants' oxygen levels also dropped during sleep, with a median low saturation of 76%.

Brain wave assessments varied among the infants. While some displayed age-appropriate EEG patterns, others indicated signs of delayed brain maturation. However, apnea measures were not significantly higher in those with immature EEG patterns, deviating from expectations.

The findings suggest that OSA and decreases in oxygen levels may present early in infants with PWS, prior to the onset of growth hormone treatment. Among the surviving infants, all began growth hormone therapy between the ages of 6 months and 2.5 years, with two undergoing adenotonsillectomy later.

The researchers concluded that their findings, alongside a review of existing literature, illustrate the urgent need for early detection and intervention for sleep apnea in infants with PWS. They called for future studies involving larger, multicenter efforts to enhance understanding of the connection between brain development and sleep disturbances, ultimately aiming to improve clinical outcomes.