Pilot study for home monitoring of cough capacity in amyotrophic lateral sclerosis: A case series.

BACKGROUND Cough capacity derangement is associated with a high risk of pulmonary complications in amyotrophic lateral sclerosis patients when cough assistance is not routinely performed at home. The primary aim of this study was to evaluate the feasibility of a long-term home based daily self-monitoring cough capacity. METHODS Eighteen subjects were enrolled in a 9-month study at home. Changes in peak cough expiratory flow, oxygen saturation, respiratory discomfort and incidence of respiratory deterioration events were evaluated. In subjects presenting respiratory deterioration events, decline in the abovementioned respiratory variables was evaluated (#NCT00613899). RESULTS During an average follow-up of 125±102 days, a total of 1175 measures were performed on 12 subjects. Mean compliance to proposed evaluations was 37±32% which worsened over time. Peak cough expiratory flow decreased by 15.08±32.43L/min monthly. Five subjects reported 6 episodes of respiratory deterioration events, after a mean period of 136±108 days. They had poor respiratory function and more years of disease. There was no difference in peak cough expiratory flow and its decline whether subjects presented respiratory deterioration events or not. In 4 subjects the respiratory discomfort score significantly worsened after respiratory deterioration events from 3.0±1.41 to 4.25±1.71. CONCLUSION Daily self-monitoring of peak cough expiratory flow, oxygen saturation and respiratory discomfort seems difficult to obtain because of poor adherence to measures; this protocol does not seem to add anything to current practice of advising on clinical derangements. Confirmatory larger studies are necessary.