Abstract
In ALS, a high prevalence of sleep apnea has been reported, both of the obstructive (OSA) and of the central type (CSA), but it is unclear if it is associated with nocturnal hypercapnia (NH) and if it is related to patients’ BMI. The aim of this study was to explore, in patients with ALS, the relationship between sleep apnea and NH, and the role of BMI as a risk factor for sleep apnea. Forty-seven patients with ALS, aged 65.4±10.4 years, admitted to our centre for a pneumological evaluation, underwent nocturnal polysomnography with transcutaneous PCO2 (TcPCO2) monitoring. NH was defined as peak TcPCO2 >49 mmHg. Patients without and with NH were compared for the occurrence of sleep apnea, defined as an apnea/hypopnea index (AHI) ≥5, separately of the central and of the obstructive type. Then, BMI of non-sleep apnea subjects was compared with BMI of OSA and CSA patients, separately in the patients without and with NH. Altogether 24 patients showed NH. Eleven patients without, and 13 patients with NH had sleep apnea (p=0.56). In the former group, 64% subjects had predominant CSA and 36% OSA, while in the latter group of patients the corresponding values were 62% and 38% (p=0.77). BMI differed among OSA (32.4±5.1 kg/m2) non-sleep apnea (26.1±4.0 kg/m2) and CSA patients (22.9±4.8 kg/m2) in the group without NH (p=0.006), but not in the group with NH (p=0.44). The similar prevalence of both OSA and CSA in the subjects without and with NH suggests that having sleep apnea is not a risk factor for nocturnal hypoventilation in ALS. A high BMI is a risk factor for OSA in normocapnic ALS patients, as it is in the general population.
Footnotes
Cite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 2954.
This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2020