OBJECTIVES: Many guidelines were released during the past decade which tried to explain appropriate drug use for patients diagnosed with COPD. Medication use in COPD is also associated with issues related to adherence and side effects. The purpose of this study was to determine trends in prescription of COPD drugs in ambulatory setting and assess the rate of change in different drug classes.
METHODS: We combined National Ambulatory Care Settings (NAMCS) and National Hospital Ambulatory Care Settings (NHAMCS) data from year 1996 to 2005. For trend analysis, data were stratified in 2-year periods. All adult visits with only primary diagnosis of COPD (ICD-9-CM: 491, 492, 496) were included in analysis and drug categories were identified using National Drug Codes. Descriptive analysis was carried out to determine patterns in drug prescription across years and four separate multivariate logistic models, dependent variable being drug class and independent variable being year, were constructed to identify rate of change in drug use across years while controlling for age, race, sex and smoking status.
RESULTS: From 1996–97 to 2004–05, total COPD visits have been increased from 0.59% to 0.77%; Prescription of anticholinergics and inhaled corticosteroids increased (17.47% to 33.48% and 12.63% to 35.19% respectively), whereas beta-agonist had no upward trend (29.46% to 29.53%). In year 1996–97, beta-agonist was the highly prescribed drug (29.46%) whereas in 2004–05, anticholinergics (33.48%) and inhaled corticosteroids (35.19%) were the top prescribed medications. From year 1996 to 2005, prescription of anticholinergics (OR- 1.088; CI-1.029–1.151) and inhaled corticosteroids (OR-1.132; CI-1.065–1.203) increased, beta agonist use has decreased (OR-0.916; CI-0.866–0.969) whereas there was no change for systemic corticosteroids (OR-1.034; CI-0.979–1.092).
CONCLUSIONS: Overall drug utilization for COPD is increasing steadily. Use of bronchodilators is increasing which is in accordance with Global initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. Corticosteroid use which is increasing should be based on risk to benefit ratio.
