Health trajectories of patients with amyotrophic lateral sclerosis before and after initiation of non-invasive ventilation: a French nationwide database analysis.

backgroundManagement of amyotrophic lateral sclerosis (ALS) is complicated by heterogeneous presentation and unpredictable disease course. This study described disease trajectories before and after initiation of non-invasive ventilation (NIV) therapy in individuals with ALS, examined the relationship between NIV initiation timing and survival and analysed health trajectory clusters.

methodsData were extracted from the French national health insurance reimbursement system database for individuals with ≥1 reimbursement for NIV from January 2015 to December 2019, and ≥1 ALS disease code. Health trajectory clusters were determined using time sequence analysis through K-clustering.

resultsWe analysed data from 3443 individuals with ALS (58% male, median age 67 years). The median (IQR) time from ALS diagnosis to NIV initiation was 10.8 (4.5-22.2) months and death occurred 21.5 (12.8-33.9) months after diagnosis. Tracheostomy/gastrostomy was performed in 3.9%/33.4% of patients, respectively. Unsupervised machine learning clustering identified four distinct patient groups. NIV initiation was late in two Clusters (A and B); these individuals were younger, had fewer comorbidities and more physiotherapy sessions before/after NIV. Survival after NIV initiation was longer in Clusters B and C; these individuals had lower rates of depression/anxiety, more prescription of mechanical in/exsufflation therapy and fewer home and emergency hospitalisations. Cluster B was unique, showing late NIV initiation and long post-NIV survival. This cluster was more likely to have spinal onset, a higher rate of obstructive sleep apnoea and fewer comorbidities.

conclusionsThere was marked heterogeneity between patients with ALS and their care trajectories. Our data do not support a universal benefit for early initiation of NIV therapy.