Ventilatory support criteria in Amyotrophic Lateral Sclerosis (ALS) patients and outcomes.

Abstract

Amyotrophic Lateral Sclerosis (ALS) represents the most common and severe motor neuron disease, with inevitable respiratory failure development. Ventilatory support (VS) has shown a valuable prognostic impact, even in bulbar-onset ALS. To analyse, ALS patients` outcomes related with VS, phenotypes or functional parameters,  a prospective study was conducted in 81 patients, with confirmed or probable ALS diagnosis, according to El Escorial criteria, sent to a pulmonology clinic for functional evaluation and/or VS prescription. From 81 patients enrolled, 11 dropped out, being only considered 70 patients (mean age 66.6±11.3 years, 64.3% males, 52.9% ALS bulbar-onset) for analysis. At admission was found hypoventilation and bulbar dysfunction symptoms, respectively, in 43 and 44 patients. During follow-up, VS was established in 50 (71.4%) patients, in almost all noninvasive ventilation (96%). A good compliance was seen in 39 patients, with residual nocturnal events only observed in 10 patients. Regarding VS initiation criteria, 24 patients were eligible by functional criteria, 14 by nocturnal hypoventilation (HV) and 12 by daytime hypercapnia. After 3-6 months of VS start, there was functional improvement in 17 patients, mainly if HV criteria. Survival after VS, was 26.3 months, but higher in compliant spinal-onset ALS patients (42.4±28.0 months; p=0.022). VS had a marked functional and survival impact, most evident in compliant spinal-onset ALS patients and when nocturnal HV was the VS criteria.