Non-invasive ventilation in neuromuscular disorders: What about sleep?

Abstract

In patients with neuromuscular disorders (NMD) and thoracic wall deformities (TWD) alveolar hypoventilation can occur once the respiratory muscles become insufficient. Non-invasive ventilation can be started to reduce hypercapnia and to improve symptoms. Previous studies in patients with NMD and TWD showed an increased survival and quality of life after initiation of NIV. Although NIV is mostly applied to reduce alveolar hypoventilation during the night, only very few studies have searched for the effect of NIV on the quantity and quality of sleep. One of the most typical symptoms of alveolar hypoventilation is increased daytime sleepiness, which has a possible negative effect on physical activity. Few small studies (n<10) have found positive effects of NIV on muscle strength and the 6 minute walking distance, but no research has been done on the effect of NIV on physical activity. In a first part we will search for the effects of NIV on the quantity and quality of sleep in patients with amyotrophic lateral sclerosis (ALS). A large group of ALS patients is in follow-up at the Neuromuscular Reference Centre of the University Hospitals Leuven. If alveolar hypoventilation occurs, most of these patients are sent on to our sleep lab to initiate NIV. By using polysomnography (objective measurement) and patient reported outcomes (subjective measurement) the effect on quantity and quality of sleep is measured. Further on, research will be performed to investigate the influence of NIV on the sympathicovagal balance and an attempt will be made to create an “ideal” protocol for titration of NIV. A second part will focus on theeffects of NIV on physical activity in patients with NMD and TWD. Physical activity will be objectively measured before and after initiation ofNIV by physical activity devices together with the measurements of physical capacity and the endurance and strength of peripheral and respiratory muscles.nrpages: 182status: publishe