Abstract
Background Whether circulating growth differentiation factor 15 (GDF-15) levels differ according to smoking status and whether smoking modifies the relationship between GDF-15 and mortality in patients with coronary artery disease are unclear. Methods and Results Using data from a multicenter, prospective cohort of 2418 patients with suspected or known coronary artery disease, we assessed the association between smoking status and GDF-15 and the impact of smoking status on the association between GDF-15 and all-cause death. GDF-15 was measured in 955 never smokers, 1035 former smokers, and 428 current smokers enrolled in the ANOX Study (Development of Novel Biomarkers Related to Angiogenesis or Oxidative Stress to Predict Cardiovascular Events). Patients were followed up during 3 years. The age of the patients ranged from 19 to 94 years; 67.2% were men. Never smokers exhibited significantly lower levels of GDF-15 compared with former smokers and current smokers. Stepwise multiple linear regression analysis revealed that the log-transformed GDF-15 level was independently associated with both current smoking and former smoking. In the entire patient cohort, the GDF-15 level was significantly associated with all-cause death after adjusting for potential clinical confounders. This association was still significant in never smokers, former smokers, and current smokers. However, GDF-15 provided incremental prognostic information to the model with potential clinical confounders and the established cardiovascular biomarkers in never smokers, but not in current smokers or in former smokers. Conclusions Not only current, but also former smoking was independently associated with higher levels of GDF-15. The prognostic value of GDF-15 on mortality was most pronounced in never smokers among patients with suspected or known coronary artery disease.