Socioeconomic gradients in tiotropium use among adults with COPD
Paul D Blanc1,2,3, Mark D Eisner1,2, Edward H Yelin4,5, Gillian Earnest1, John R Balmes1,2, Steven E Gregorich6, Patricia P Katz4,5
1Division 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, USA
Background: 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
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Download Article [PDF]