Characteristics of sleep disordered breathing in pediatric spinal muscular atrophy

Abstract

RATIONALE Sleep disordered breathing (SDB) causing sleep disturbance and daytime symptoms occurs in spinal muscular atrophy (SMA). Although polysomnography (PSG) findings are well described in other neuromuscular disorders, there are only limited reports of PSG findings in the pediatric SMA group in the literature, especially in SMA type one. The aim of this study was to characterise SDB and non-invasive ventilation (NIV) use in childhood SMA. This is the largest study describing PSG findings in pediatric SMA. METHODS This cross-sectional cohort study was of all children with SMA in the state of Queensland, Australia. Children were Nusinersen naïve and were having their yearly follow-up full diagnostic PSG in 2018. The PSG was scored and reported by a single paediatric sleep physician in accordance with American Academy of Sleep Medicine Guidelines (2012). RESULTS 28 children (16 males) were included (0.75-18.7 years). Significant SDB was defined as apnoea-hypopnea index (AHI) of greater than five events per hour; normal breathing was defined as an AHI of less than one event per hour. SDB was seen in each type (See Table 1) with a predilection to the rapid eye movement stage of sleep. In SMA type one, all patients exhibited SDB, two (50%) with central sleep apnoea (CSA) and two (50%) with mixed disease. In SMA type two, five (33%) had CSA, one (7%) mixed disease, seven (47%) had early SDB and two (13%) had normal sleep breathing. Lastly, for SMA type three, four (44%) children had CSA and five had early SDB. Indications used to commence NIV in this cohort was significant SBD, transcutaneous carbon dioxide levels greater than 50mmHg on PSG or recurrent lower respiratory tract infections requiring NIV. Starting NIV significantly improved mean total PSG AHI scores (16.5 events per hour pre-commencement of NIV (SD ± 14.8; 95% CI 6.5-26.4) versus post NIV 4.0 (SD ± 4.3, 95% CI 1.1-6.9) p= 0.01). CONCLUSION This is the largest study describing SBD in paediatric SMA. It revealed SDB is common in childhood SMA and was present in children with all types of SMA (types one to three). Central sleep apnoea was the most common SDB present, although mixed SDB was also present in SMA type one and type two. SDB improved with initiation of NIV. (Figure Presented).L6303495142020-01-01 <br />