The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts

PREDICTORS OF FUNCTIONAL DECLINE IN ALS PATIENTS UNDER NIV.

Anna C. Braga1, Jose Pedro Almeida1, Anabela Pinto1,2, Mamede de Carvalho1; 1Unidade de Fisiologia ClĂ­nica Translacional, Instituto de Medicina Molecular /Faculdade de Medicina de Lisboa, Lisboa, Portugal; 2Physical Medicine and Rehabilitation Service, Centro Hospitalar Lisboa Norte, Lisboa, Portugal

Background: The lack of more specific tools, with low costs, which may be associated with the ALSFRS score to assist in analyzing the prognosis is a constraint factor in the follow up of ALS ventilated patients. We analyzed potential predictors that can be related with rate of functional decline measured by ALSFRS in ALS patients. Methods: Prospective, comparative trial of sixty consecutive ALS patients, were assigned to two groups, G1 (n=29) included all dead patients who had been compliant to NIV, and G2 (n=31) included all compliant subjects within the same period of time that were alive at the end of the study. All patients were followed-up with ALSFRS, oximetry, respiratory function evaluation and blood gases analysis at each three months and all data were registered with respective dates to compare timings to NIV adaptation and total use. Primary outcomes included ALSFRS functional decline and disease duration; secondary outcomes included time to NIV, FVC at disease duration, oximetry data and parameters settings at NIV adaptation. A Cox regression analysis determined independent predictors of respiratory function on rate of decline of ALSFRS. Results: No clinical or laboratorial differences were observed between groups for any variable at admission. Disease duration (in days) from symptoms was higher in G2, as well as duration to NIV, but not significant. These 2 variables correlate positively with maximal inspiratory pressure (MIP; p=0.02), IPAP (P=0.041) and backup breathing rate (BR; p=0.038). Multivariate Cox regression analysis showed that ratio I:E (p=0,023), IPAP (p=0,05), EPAP (p=0,035), Inspiratory Sensitive (p= 0,002), Expiratory Sensitive (p=0,019), Rise Time (p=0,030), Maximal Expiratory Pressure (p=0,042), P.01 (p=0,012) and SatO2 (p=0,02) were associated with rate of functional decline in these patients. Conclusions: For the first time, determinants of functional decline are significantly related to parameters settings of NIV equipments as well as to compliance data suggesting that NIV may be considered a modifiable treatment disease if and when a more rigorous management of NIV is achieved. Sponsored Research - None