Demographic Characteristics and Clinical Outcomes in Patients from Latin America Versus the Rest of the World: A TIOSPIR® Post-Hoc Analysis.

INTRODUCTION: Geographical variations may impact outcomes in chronic obstructive pulmonary disease (COPD). We evaluated differences in baseline characteristics and outcomes between patients enrolled in Latin America compared with the rest of the world (RoW) in the TIOtropium Safety and Performance In Respimat® (TIOSPIR®) trial.

METHODS: TIOSPIR®, a 2-3-year, randomized, double-blind trial (n=17116; treated set), compared safety and efficacy of once-daily tiotropium Respimat® 5 and 2.5μg with tiotropium HandiHaler® 18μg. This post-hoc analysis pooled data from all treatment arms to assess mortality, exacerbations, cardiac events, and serious adverse events (SAEs) between both regions.

RESULTS: At baseline, patients enrolled in Latin America (n=1000) versus RoW (n=16116) were older, with higher pack-years of smoking history and more exacerbations, but less cardiac history. In this analysis, patients in Latin America versus RoW had an increased risk of death (hazard ratio [HR] [95% confidence interval (CI)]: 1.52 [1.24-1.86]; P<.0001) or moderate-to-severe exacerbation (HR [95% CI]: 1.29 [1.18-1.41]; P<.0001), but a lower risk of severe exacerbation (HR [95% CI]: 0.82 [0.68-0.98]; P=.0333). SAE rates in Latin America were lower versus RoW (incidence rate ratio [IRR] [95% CI]: 0.82 [0.72-0.92]), including cardiac disorders (IRR [95% CI]: 0.68 [0.48-0.97]). Risk of major adverse cardiovascular events were similar (HR [95% CI]: 0.99 [0.71-1.40]; P=.9677).

CONCLUSIONS: TIOSPIR® patients in Latin America had a higher risk of death or moderate-to-severe exacerbation, but a lower risk of severe exacerbation than those in RoW. Geographical differences may impact outcomes in COPD trials.