Which are the factors influencing NIV adaptation and tolerance in ALS patients?

Amyotrophic lateral sclerosis (ALS) is a multisystemic disease compromising both the neuromuscular system and the cognitive status. Non-invasive ventilation (NIV) has been shown to improve survival and quality of life in ALS patients with respiratory failure, but scanty literature investigated which are the predictors of NIV tolerance. The aim of this study was to evaluate the impact of functional, cognitive, neurobehavioral, and respiratory status on NIV compliance and tolerance in patients with ALS. We retrospectively evaluated clinical data of ALS patients who consecutively underwent a NIV trial during hospitalization. Cognitive and neurobehavioral assessments have been performed using the Edinburgh Cognitive and Behavioral ALS Screen (ECAS), the Hospital Anxiety and Depression Scale (HADS), the Frontal Assessment Battery (FAB), the Raven's 47 Colored Progressive Matrices (PM47), and the Neurobehavioral Rating Scale Revised (NRSR). Seventy-two patients (mean age +/- SD; 63.9 +/- 10.6 years) were included. Patients adapted were 63/72 (87.5%). The average time of adaptation was 7.82 +/- 5.27 days. The time required to reach a satisfying NIV adaptation was significantly related to the presence of sialorrhea (p= 0.02), respiratory status (Borg Dyspnoea Scale,p= 0.006, and ALS-FRS-R respiratory subscore,p= 0.03) and behavioral and cognitive impairment (NRSR-F1,p= 0.04, NRSR- F5,p= 0.04). Presence of sialorrhea and neurobehavioral impairment, and absence of respiratory symptoms are negative predictors of NIV adaptation. This study highlights the need of a multidisciplinary patient-tailored approach including cognitive-behavioral assessment and a psychological support program to optimize patient's training and compliance to NIV.