Limitations of sniff nasal pressure as an outcome measurement in amyotrophic lateral sclerosis patients in a clinical trial.
- Bauer M Neuromuscular Diseases Unit/ALS Clinic, Kantonsspital St. Gallen, Switzerland.
- Czell D
- Hartmann S
- Goldman B
- Müller D
- Weber M
- 2012-08-01
Published in:
- Respiration; international review of thoracic diseases. - 2012
Adult
Aged
Amyotrophic Lateral Sclerosis
Feasibility Studies
Female
Humans
Inhalation
Male
Middle Aged
Nose
Outcome Assessment, Health Care
Posture
Pressure
Vital Capacity
English
BACKGROUND
The forced vital capacity (FVC) is an established measure in amyotrophic lateral sclerosis (ALS) clinical trials. Recently the sniff nasal inspiratory pressure (SNIP) test has been increasingly used as a respiratory measure.
OBJECTIVES
It was the aim of this study to assess the feasibility of SNIP as an outcome measure in a phase III clinical trial with a lead-in design.
METHODS
Twenty patients were enrolled in a randomized clinical trial. FVC, SNIP in sitting (SNIPsitt) and supine (SNIPsup) positions, and the ALS functional rating scale score (ALSFRS-R) were measured every 4 weeks.
RESULTS
Complete data were available for 19 patients over 5 months. Baseline values were normal for FVC (101 ± 14%) but abnormal for SNIPsitt and SNIPsup (84 ± 34% and 82 ± 33%). While FVC and ALSFRS-R declined in parallel, SNIPsitt measures declined significantly less compared to ALSFRS-R (p < 0.05) and FVC (p < 0.001) up to 4 months after enrollment. Over 50% of patients still had values equal to or above baseline SNIPsitt measures after 3 months despite abnormal baseline values.
CONCLUSIONS
The delayed decline in SNIP measurements suggests a learning effect over time. The optimal number of SNIPs in ALS clinical trials has yet to be determined. SNIP measures should be used with caution in trials with a lead-in design.
The forced vital capacity (FVC) is an established measure in amyotrophic lateral sclerosis (ALS) clinical trials. Recently the sniff nasal inspiratory pressure (SNIP) test has been increasingly used as a respiratory measure.
OBJECTIVES
It was the aim of this study to assess the feasibility of SNIP as an outcome measure in a phase III clinical trial with a lead-in design.
METHODS
Twenty patients were enrolled in a randomized clinical trial. FVC, SNIP in sitting (SNIPsitt) and supine (SNIPsup) positions, and the ALS functional rating scale score (ALSFRS-R) were measured every 4 weeks.
RESULTS
Complete data were available for 19 patients over 5 months. Baseline values were normal for FVC (101 ± 14%) but abnormal for SNIPsitt and SNIPsup (84 ± 34% and 82 ± 33%). While FVC and ALSFRS-R declined in parallel, SNIPsitt measures declined significantly less compared to ALSFRS-R (p < 0.05) and FVC (p < 0.001) up to 4 months after enrollment. Over 50% of patients still had values equal to or above baseline SNIPsitt measures after 3 months despite abnormal baseline values.
CONCLUSIONS
The delayed decline in SNIP measurements suggests a learning effect over time. The optimal number of SNIPs in ALS clinical trials has yet to be determined. SNIP measures should be used with caution in trials with a lead-in design.
- Language
-
- English
- Open access status
- bronze
- Identifiers
-
- DOI 10.1159/000339415
- PMID 22846608
- Persistent URL
- https://folia.unifr.ch/global/documents/125413
Statistics
Document views: 15
File downloads:
- fulltext.pdf: 0