Socioeconomic gradients in tiotropium use among adults with COPD

• Main Authors: Paul D Blanc, Mark D Eisner, Edward H Yelin, Gillian Earnest, John R Balmes, et al
• Format: Article
• Language: English
• Published: Dove Medical Press 2008-10-01
• Series: International Journal of COPD
• Online Access: http://www.dovepress.com/socioeconomic-gradients-in-tiotropium-use-among-adults-with-copd-a2463
• ISSN: 1176-9106; 1178-2005

Paul D Blanc1,2,3, Mark D Eisner1,2, Edward H Yelin4,5, Gillian Earnest1, John R Balmes1,2, Steven E Gregorich6, Patricia P Katz4,51Division of Occupational and Environmental Medicine, 2Division of Pulmonary and Critical Care Medicine, 4Division of Rheumatology, 6Division of General Internal Medicine, Department of Medicine; 3Cardiovascular Research Institute; 5Institute for Health Policy Studies; University of California San Francisco, San Francisco, CA, USABackground: Inequalities in the use of new medications may contribute to health disparities. We analyzed socioeconomic gradients in the use of tiotropium for chronic obstructive pulmonary disease (COPD).Methods: In a cohort of adults with COPD aged ≥55 years identified through population-based sampling, we elicited questionnaire responses on demographics, socioeconomic status (SES; lower SES defined as high school education or less or annual household income <US $20,000), and medication use and other clinical variables. In a subset we obtained pulmonary function testing. We used multiple logistic regression analysis to estimate the associations between SES and tiotropium use in COPD, adjusting for disease severity measured by a COPD Severity Score.Results: Of 427 subjects, 44 (10.3%) reported using tiotropium in 2006. Adjusting for COPD severity, lower SES was associated with reduced odds of tiotropium use (OR 0.3; 95% CI 0.1–0.7; p = 0.005). Among the subset with lung function data (n = 95), after including COPD Global Obstructive Lung Disease (GOLD) Stage ≥2 in the model, lower SES remained associated with reduced odds of tiotropium use (OR 0.03; 95% CI < 0.001–0.7; p = 0.03). Including forced expiratory volume in one second in the model as a continuous variable instead of GOLD Stage ≥2 yielded similar results for lower SES (OR 0.1; 95% CI < 0.001–0.5; p = 0.02).Conclusion: There was a strong SES gradient in tiotropium use such that there was less use with lower SES. To the extent that this is an efficacious medication for COPD, this gradient represents a potential source of health disparities.Keywords: socioeconomic status, COPD, tiotropium, medication, health gradients