Abstract
Background Inhaled steroids (IS) are often used in the treatment of COPD and are consistently associated with adverse effects such as pneumonia, thrush and adrenal suppression, however their effect on the incidence or worsening of existing diabetes (DM) is unclear. We attempted to investigate this using record linkage in a Dundee COPD population.
Methods COPD patients in Tayside are visited annually and their data, including demographics, spirometry, treatment, symptoms and outcomes are entered into a managed clinical database. Prescription datasets were used to determine IS exposure. A separate DM dataset was used to determine new DM diagnosis and worsening of existing DM defined as an increase in glycosylated haemoglobin or the need for new or increased DM medication. A Cox regression model was used to determine the association between IS use and new DM or worsening of existing DM after adjusting for potential confounders. A time dependent analysis of exposure comparing time on versus off IS was used to take into account patients changing their exposure status during follow-up and to prevent immortal time bias.
Results 4305 subjects (3243 exposed to IS with a total of 17,229 person-years of exposure and 1062 non exposed) were eligible for the study. Fluticasone was responsible for 67.7% of the IS exposure. There were 239 cases of new DM and 265 cases of worsening DM. The hazard ratio for the association between cumulative IS and new DM diagnosis was 0.70 (0.43-1.12), that of worsening of existing DM was 0.57 (0.24-1.37).
Conclusion There was no association between IS use and either new cases of DM or worsening of existing DM in our dataset.
- © 2014 ERS
