Dados do Trabalho

Título

CORRELATION BETWEEN POLYSOMNOGRAPHIC FEATURES AND MUSCLE STRENGTH AMONG CHILDREN WITH NEUROMUSCULAR DISEASES IN A TERTIARY CARE CENTRE OF SAO PAULO.

Introdução

Neuromuscular diseases (NMD) covers a range of genetic disorders that share muscle weakness as a common symptom. As during sleep there are physiological respiratory changes not great enough to maintain normal gas exchange, the intrinsic muscle weakness of these pathologies can be manifested as sleep-related breathing disorders (SBD), like hypoventilation or sleep apnea. The most reliable method for diagnosing these disorders, yet poorly available, is Polysomnography (PSG) with capnography, while spirometry offers a limited additional perspective.

Objetivo

The main goal was to describe the respiratory polysomnographic features, such as apnea hypopnea index (AHI) and desaturation time below 90% (P90) analyzed according to muscle strength focusing on upper limbs and cervical region.

Método

We made a retrospective cohort study of NMD patients from data collected between 2016 and 2023. All patients were under regular follow-up at a specialized NMD outpatient clinic at a public hospital from São Paulo. We emphasized our analysis on strength levels both distal and proximal upper limbs and the neck and on respiratory data, with forced vital capacity (FVC) from spirometry and AHI.

Resultados

We analyzed 31 type 1 PSG from children and adolescents aged 4 to 19 years old (14 ± 7), of which 65% were diagnosed with Duchenne Muscular Dystrophy (DMD); 19% with Congenital Muscular Dystrophy (CMD); 13% with Spinal Muscular Atrophy (SMA) and 3% with Steinert Myotonic Dystrophy. We called normal the strength levels 4 and 5, against 1, 2 and 3 as reduced. Among the proximal weakness group, they presented medium minimal oxygen saturation (SaO2) of 83% ± 7SD (p=0,194) and P90 of 0,1% ± 0,14SD (p=0,381); the distal weakness group presented medium minimal SaO2 of 90,5% ± 3 (p=0,301) and no saturation time below 90% (p=1); the reduced cervical strength group presented medium minimal SaO2 of 87,5% ± 7SD (p=1) and P90 of 20,5% ± 29SD (p=0,335).

Conclusão

Overall, NMD patients included in this study presented reduced minimal oxygen saturation and increased time below 90% saturation among this population when compared to standard values. It can be explained by progressive muscle weakness and obesity secondary to the loss of ambulation and use of corticosteroids. To end, we hypothesize that those two parameters are important in the evaluation of a PSG in a patient with NMD.

Referências

CHIDAMBARAM, A. G. et al. Sleep Disordered Breathing in Children with Neuromuscular Disease. Children (Basel, Switzerland), v. 10, n. 10, p. 1675, 11 out. 2023.
HURVITZ, M. S. et al. Characterization of sleep-disordered breathing in children with Duchenne muscular dystrophy by the American Academy of Sleep Medicine criteria vs disease-specific criteria: what are the differences? Journal of clinical sleep medicine: JCSM: official publication of the American Academy of Sleep Medicine, v. 18, n. 2, p. 609–616, 1 fev. 2022.
LI, L. et al. Sleep apnoea and hypoventilation in patients with five major types of muscular dystrophy. BMJ open respiratory research, v. 10, n. 1, p. e001506, abr. 2023.
MACKINTOSH, E. W.; CHEN, M. L.; BENDITT, J. O. Lifetime Care of Duchenne Muscular Dystrophy. Sleep Medicine Clinics, v. 15, n. 4, p. 485–495, dez. 2020.
MARY, P.; SERVAIS, L.; VIALLE, R. Neuromuscular diseases: Diagnosis and management. Orthopaedics & traumatology, surgery & research: OTSR, v. 104, n. 1S, p. S89–S95, fev. 2018.

Palavras Chave

Polysomnography; neuromuscular; respiratory