Outcomes Associated With Tiotropium Use in Patients With Chronic Obstructive Pulmonary Disease

Background: To date, there is mixed evidence on the safety and effectiveness of tiotropium. Our objective was to evaluate the comparative effectiveness of regimens containing tiotropium bromide vs other medication regimens for chronic obstructive pulmonary disease (COPD) in real-world clinical settings. Methods: We conducted a cohort study on 2 separate cohorts with a diagnosis of COPD in the Veterans Affairs health care system. Patients with a diagnosis of COPD prescribed tiotropium and patients in a historic cohort prior to the introduction of tiotropium were selected for comparison using propensity scores, with the base case including scores from 0.1 to 0.4. Outcomes identified during follow-up were all-cause mortality, COPD exacerbations, and COPD hospitalizations. Exposure to COPD medication regimens was defined in a time-varying manner and Cox proportional hazards regression were used to evaluate outcomes. Results: For 42 090 patients in the base case, the regimen of tiotropium + inhaled corticosteroids (ICS) + long-acting beta-agonists (LABA) was associated with 40% reduced risk of death (hazard ratio [HR], 0.60; 95% confidence interval [CI], 0.45-0.79) compared with ICS + LABA. This combination was associated with reduced rates of COPD exacerbations (HR, 0.84; 95% CI, 0.73-0.97) and COPD hospitalizations (HR, 0.78; 95% CI, 0.62-0.98). Tiotropium in combination with 2 other medications was associated with increased risk of mortality, exacerbations, and hospitalizations. Conclusions: When used with ICS and LABA, tiotropium use was associated with a decreased risk of mortality compared with treatment with ICS and LABA. However, this result was not consistent in other medication regimens that included tiotropium. Patients and health care providers are often confronted by treatment alternatives with limited information by which to make decisions. One prominent gap in clinical information is the lack of direct comparisons between treatments, because much of the evidence in clinical practice guidelines comes directly from placebo-controlled trials rather than head-to-head comparisons. Enrolling patients in trials that use rigid inclusion and exclusion criteria often leads to selected populations who may be different from those ultimately using the medication.(1,2) Thus, to complement results from placebo-con trolled trials, comparative effectiveness studies of treatment interventions are increasingly conducted to inform decision making for more general populations.(3)