Authors: Wilson Marques Junior Mônica de Carvalho Alcântara Marcello H NogueiraBarbosa Regina Maria França Fernandes Geruza Alves da Silva Heide H Sander Charles Marques Lourenço
Publish Date: 2015/03/13
Volume: 262, Issue: 5, Pages: 1164-1171
Abstract
We aimed to investigate the relationship between neurological compromise respiratory parameters in wakefulness and in sleep physiology and morphology of phrenic nerves in patients with Charcot–Marie–Tooth disease type 1A CMT1A Sixteen patients with CMT1A were evaluated by spirometry maximal expiratory and maximal inspiratory pressures MEP MIP polysomnography phrenic nerve compound muscle action potential CMAP and ultrasonography roots C3C4C5 and phrenic nerves Clinical disability was measured with Charcot–Marie–Tooth neuropathy score CMTNS range 0–36 Two control groups comprising 30 individuals matched for age sex and body mass index were used for comparison Ten patients were female 62 mean age was 3788 years range 24–76 and CMTNS range was 7–34 MIP was reduced in five 31 and MEP in 12 patients 75 although only one had restrictive respiratory dysfunction in spirometry Apnoea–hypopnea index AHI was significantly higher in patients 1201 ± 1157/h × 589 ± 836/h p value = 005 and increased in REM sleep compared with NREM 994 ± 1096/h × 1913 ± 1993/h p value = 001 There were significant correlations between CMTNS and AHI Pearson = 069 p value = 003 CMTNS and MIP Pearson = −0691 p value = 0003 and CMTNS and MEP Pearson = −0603 p value = 0013 Also AHI showed negative correlation with MIP Pearson = −052 p value = 0036 and MEP Pearson = −055 p value = 0026 Phrenic nerves were enlarged in ultrasonography in all patients and presented significant correlations with CMAPs right Pearson = −0554 p value = 0026 left Pearson = −0558 p value = 0025 We suggest that axonal degeneration of nerves directed to muscles of respiration might explain the high prevalence of respiratory weakness in patients with CMT1A Clinical manifestations are frequent during sleep where the diaphragm alone can only partially surpass the overload in breathing apparatus
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