Letter by Smolderen and Pelle Regarding Article, “Efficacy and Safety of Varenicline for Smoking Cessation in Patients With Cardiovascular Disease: A Randomized Trial”
To the Editor:
The Varenicline trial for smoking cessation in patients with cardiovascular disease (CVD)1 caught our attention when we attended the “Smoking the Ignored Risk Factor: The Elephant in the Room” symposium at the 2009 European Society of Cardiology conference, at which the first results were presented. Although we could not have been more pleased with an entire session being devoted to the importance of smoking cessation, we shared some concerns about the systematic exclusion of several important subpopulations of patients with CVD—among them, patients with comorbid depression—with the hopes that these concerns would be addressed when trial results were published.
When reading the full text of the study’s results, we unfortunately noted that the authors did not explain in more detail the consequences of excluding patients with comorbid depression or patients taking antidepressants in the past year. Although we can appreciate the reserve that the research team had when determining the exclusion criteria for patients’ psychiatric background, foreshadowing potential harmful side effects, we feel that an important opportunity was missed by not addressing the rationale and implications of this choice.
Because numerous studies have discussed the increased prevalence of depression in patients with CVD (range, 17% to 47%),2 this study likely ignored a significant and vulnerable proportion of patients with CVD seen in routine clinical practice. Not only does this result in a less representative sample, but a patient group that may be most in need of an effective smoking cessation strategy has been overlooked in this trial.
It is known that smoking cessation is an enormous challenge in those presenting with depressive symptoms because of their intertwinedness, with depressed patients presenting with higher smoking rates and experiencing higher rates of relapses after initiating a smoking cessation strategy3 compared with those without these symptoms. From a clinical point of view, it would have been interesting to know the success rates and the occurrence of psychiatric adverse events if depressed patients were not excluded. Because both smoking and depression are important risk factors of adverse outcomes in CVD, we feel that is important to maximize preventive efforts in this vulnerable group, and we strongly believe that a trial that has attracted considerable publicity missed an opportunity by excluding a vulnerable proportion of patients who may have the most to gain from potentially effective smoking cessation strategies.
The publicity raised by this drug trial creates an opening to ask for increased awareness for this ignored high-risk patient group, consistent with the work on depression, smoking cessation, and CVD4,5 by the lead author of the Varenicline trial article, Dr Rigotti, which we would very much like to applaud. We further encourage the field to direct future research efforts toward documenting the effects of depression and smoking on outcomes in CVD and hope that future studies addressing the efficacy and safety of new drug-supported smoking cessation therapies in CVD patients with comorbid depression, preferably accompanied by behavioral strategies, are currently on their way.