Smokers Undergoing TAVR Have Higher Comorbidity Burden Than Nonsmokers

Current or recent smokers who undergo transcatheter aortic valve replacement (TAVR) tend to be younger and have a higher comorbidity burden than nonsmokers who undergo TAVR, according to a study recently published in Journal of the American Heart Association. These comorbidities may result in worse survival rates among smokers in long-term recovery.

This study included 72,165 individuals (median age, 83 years; 48% women) in the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry, all of whom underwent TAVR in the United States from November 2011 to June 2016. Of these, 42,694 had available data on 1-year postdischarge mortality and stroke, myocardial infarction, and heart failure rehospitalizations; these comprised the clinical cohort.

At the time of TAVR, the study patients were classified as either previous/nonsmokers or current/recent smokers. All-cause mortality in ≤1 year of discharge was the primary outcome. The 12-item Kansas City Cardiomyopathy Questionnaire–Overall Summary Score (KCCQ‐OS) was used to assess health status at different time points throughout the study period. Wilcoxon rank sum tests were used to compare continuous variables between smoker groups, while Pearson chi-square tests were used to compare categorical variables. Multivariable models were used to investigate associations between smoking status and KCCQ-QS, in-hospital outcomes, mean gradient, 1-year mortality, and rehospitalization.

Among the study population, 5.6% (n=4063) were current or recent smokers. This group was younger at the time of TAVR (75 [68-81] years) compared with nonsmokers (83 [77-88] years; P <.001), more likely to be men, and had higher burden of moderate to severe lung disease (51.1% vs 25.8%; P <.001). This group also had a lower Society of Thoracic Surgeons Predicted Risk of Mortality score (5.6% vs 6.4%; P <.001), as well as lower in-hospital mortality (relative risk 0.74; 95% CI, 0.62-0.89; P =.001), but not in-hospital myocardial infarction or stroke.

No significant association was identified between smoking status and postdischarge heart failure, mortality, stroke, or myocardial infarction; however, 1-year mean aortic valve gradients were higher (11.1 vs 10.2 mm Hg; P <.001), and KCCQ-OS scores were 2.4 points lower among smokers (P =.031).

Limitations to this study include the inability to distinguish between current and recent smokers, a lack of data on smoking cessation in the follow-up period, missing data on follow-up echocardiography and KCCQ, a lack of data on outcomes beyond 1 year, and small intergroup differences in both aortic valve gradients and health status.

The study researchers concluded that “[although] only 5.6% of patients undergoing TAVR in the United States are current or recent smokers, these patients are generally younger with a greater burden of comorbidities.” These comorbidities are at least partly attributable to smoking. Although in-hospital survival rates were higher among these individuals, likely due to their youth, similar postdischarge survival rates suggest that their higher comorbidity burden may hinder recovery.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Qintar M, Li Z, Vemulapalli S, et al. Association of smoking status with long‐term mortality and health status after transcatheter aortic valve replacement: insights from the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry [published online August 20, 2019]. J Am Heart Assoc. doi:10.1161/JAHA.118.011766