ESPE Abstracts

Background: Imprinting disease such as Prader-Willi syndrome (PWS) are associated with pathological sleep due to central and obstructive apneas. No data are available concerning Silver Russell syndrome (SRS) but most patients describe day asthenia and snoring. These patients also often present with maxillo-facial malformations.

Aims and objectives: We wanted to characterise sleep in SRS and evaluate GH therapy possible effect on it.

Methods: We analysed 54 sleep polygraphies and polysomnographies in 40 patients with genetically proven SRS (i.e 31 with 11p15 epimutation and nine with mUPD7), 19 prior to GH therapy, 34 during GH therapy and one after GH therapy. Five patients had sleep evaluation prior and after GH therapy initiation.

Results: Sleep showed pathological patterns in all but one children before GH therapy (n=19). Obstructive apneas were mainly implicated with a mean obstructive respiratory events index (REI) of 4.5 (1.2–16.4). Large tonsils were identified in eight patients by ear-nose-throat (ENT) examination, half were removed. Sleep abnormalities were severe in two patients, moderate in 11 and mild in five before GH therapy. We performed five polysomnographies with a sleep efficiency of 80.3% and microwakennings index of 14.2 per h. The mean REI was 5.6 (0–18.5) in all recordings. Preliminary results showed no worsening of the REI after GH initiation.

Conclusion: Patients with SRS present sleep obstructive apneas syndrome that should be evaluated before GH therapy onset. Maxillo-facial abnormalities and tonsil hypertrophy could be implicated in such sleep pattern and we recommend systematic evaluation in SRS patients, preferably before GH therapy initiation, even if it seems to have no worsening effect on sleep features. High microwakennings index could contribute to day asthenia often describe in SRS patients. Caution should be given to central apnea presence even if not predominant they could testify of hypothalamic involvement as in PWS patients.