Use of tiotropium Respimat versus HandiHaler and mortality in patients with COPD.

VERHAMME et al. [1] recently compared the possible mortality effect of two delivery systems of tiotropium in their Dutch observational cohort study of 11 287 chronic obstructive pulmonary disease (COPD) first-time users of tiotropium in primary care. They concluded that ‘‘until further data become available, physicians should be aware that patients with arrhythmia or a history of cardiovascular disease might be particularly at risk’’ when using tiotropium Respimat [1]. Although arrhythmia, renal disease and certain cardiac diseases are relative contraindications of tiotropium and, clinically, it may be important to consider whether an increased mortality risk in such patients with these relatively contraindicative comorbidities overrides the additional well-being of the bronchodilatation effect of tiotropium therapy. The evidence on this question is sparse or not available; thus independent randomised trials may be needed. Several publications have considered the pro-arrhythmogenic character and possible detrimental dose-dependent effects of anticholinergics in COPD patients with co-incident cardiac disease or renal disease (assigned to decreased drug excretion). A recent publication found that a large proportion of real life COPD patients (38%) may have such comorbidity and, therefore, be ineligible for inclusion in the previously performed randomised controlled trials [2].