Growth hormone (GH) is licensed in Prader Willi syndrome (PWS) for improvement of body composition, (1-3) height velocity, mobility, behaviour and quality of life. (4) Recent case reports however have pointed out the occurrence of sudden death during initiation of GH, mainly during sleep and possibly related to severe obesity and sleep disordered breathing (SDB). (5-15) Concerns for an increased mortality in PWS children initiated on GH therapy led to a call for cessation of its use.
Children with PWS are at risk of developing SDB secondary to both deficient autonomic sleep control and upper airway obstruction (UAO). It has been suggested that GH might exacerbate pre existing gas exchange deficiencies in three ways: a) by stimulation of adenotonsillar hypertrophy; (16;17) b) by a rise of basal metabolic rate with resultant rise in oxygen demand; (18) and c) by normalisation of previously decreased hydration with augmentation of volume load. (19)
Are we withholding GH therapy, a treatment known to be of benefit in PWS, without adequate evidence to justify our actions? We consider it safe to treat severely obese children with GH once SDB is addressed with respiratory support such as continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP). In this paper, we evaluate the current evidence for the use of GH in PWS from a respiratory bias and propose a pathway for the identification and monitoring of these "at risk" patients.
- Adverse effects
- Growth hormone
- Prader Willi syndrome
- Sleep disordered breathing
- Sudden death