Related Experiment Videos
Variability of pulmonary function tests in stable corticosteroid dependent asthma patients
W B Klaustermeyer1, K S Garb, S M Santiago
1Allergy and Immunology Section, Wadsworth VA Medical Center, West Los Angeles, California 90073.
Allergy Proceedings : the Official Journal of Regional and State Allergy Societies
|July 1, 1991
Summary
Establishing a reliable baseline over several months is crucial for accurately assessing steroid-sparing agents in asthma patients due to significant weekly variability in lung function. Shorter baseline periods are inadequate.
Area of Science:
- Pulmonology
- Clinical Pharmacology
Background:
- Corticosteroid dependence in asthma necessitates exploring alternative treatments like steroid-sparing agents.
- Accurate assessment of therapeutic efficacy requires reliable patient baseline data.
Purpose of the Study:
- To establish a baseline for future clinical trials of corticosteroid-sparing agents in corticosteroid-dependent asthmatics.
- To evaluate the adequacy of short-term (1-2 months) baseline data collection in this patient population.
Main Methods:
- Longitudinal study of 24 corticosteroid-dependent asthmatic patients over 10 months.
- Collected data included clinical symptoms, corticosteroid dose, peak expiratory flow (PF), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC).
- Analyzed correlations between lung function parameters, symptom severity, time, and corticosteroid dosage.
Main Results:
- Significant weekly variability observed in PF and FEV1 measurements.
- Over nearly a year, 54% of patients showed no significant change in PF, while 29% worsened and 17% improved.
- Neither patient-reported symptom severity nor corticosteroid dosage correlated with objective spirometric measurements.
Conclusions:
- A minimum baseline period of several months is necessary to account for weekly variability and accurately assess treatment effects in corticosteroid-dependent asthmatics.
- Current 1-2 month baseline assessments are insufficient for this population.
- Objective spirometry is essential, as subjective symptom assessment and steroid dose do not reliably correlate with lung function.