Education＆ScienceEducational Article

Comment by Mark Lavercombe: In a cohort of 224 smoking patients with COPD from Beijing, the authors of this study use the nicotine metabolite ratio (NMR) to evaluate both varencline and bupropion for smoking cessation. After stratification as ‘normal’ or ‘slow metabolisers’ based on their measured ratio of trans-30-hydroxycotinine to cotinine, varenicline proved to have superior efficacy in smoking cessation in those with normal NMR. While no difference in efficacy was seen in the slow metaboliser group, there were more side effects with varenicline than bupropion. The authors suggest further study on the value of NMR in the selection of smoking cessation strategies, and the single-centre nature of this work requires replication in other settings.