Yun Gi Kim1, Jung-Won Suh2, Si-Hyuck Kang3, Jin Joo Park3, Chang-Hwan Yoon3, Young-Seok Cho3, Tae-Jin Youn3, In-Ho Chae3, Dong-Ju Choi3, Hyo-Soo Kim4. 1. Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea; Cardiovascular Center & Department of Internal Medicine, Seoul National University Hospital, Jongno-gu, Seoul, Korea. 2. Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea. Electronic address: dasome2@snu.ac.kr. 3. Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea. 4. Cardiovascular Center & Department of Internal Medicine, Seoul National University Hospital, Jongno-gu, Seoul, Korea.
Abstract
OBJECTIVES: The authors performed this analysis to examine whether the enhanced clopidogrel responsiveness in current smokers is maintained after adjusting the influence of hemoglobin on VerifyNow P2Y12 reaction unit (PRU). BACKGROUND: PRU is consistently reported to be lower in current smokers. However, PRU has a significant inverse relationship with hemoglobin level, and smokers have higher hemoglobin levels. Because the association between PRU and hemoglobin is likely to be an in vitro phenomenon, we hypothesized that the observed difference in PRU between nonsmokers and current smokers is the result of confounding effect of hemoglobin rather than true difference in platelet reactivity. METHODS: Three cohorts were combined for the analysis (SNUBH [Seoul National University Bundang Hospital], n = 459; CILON-T [influence of CILostazol-based triple antiplatelet therapy ON ischemic complication after drug-eluting stenT implantation], n = 715; HOST-ASSURE [Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen], n = 1,357). The final combined cohort consisted of 1,314 patients who underwent percutaneous coronary intervention and had VerifyNow P2Y12 assay results. General linear model (analysis of covariance) was used to control the effect of hemoglobin on PRU. RESULTS: A significant inverse correlation was observed between PRU and hemoglobin (r = -0.389; p < 0.001). Current smokers showed a significantly higher hemoglobin level (13.5 ± 1.6 vs. 14.4 ± 1.5; p < 0.001) but lower PRU level (230.1 ± 90.7 vs. 212.2 ± 83.6; p < 0.001). After adjusting the influence of hemoglobin on PRU, there was no difference in PRU between nonsmokers and current smokers (224.1 [95% confidence interval: 218.7 to 229.5] vs. 225.3 [95% confidence interval: 217.2 to 233.3]; p = 0.813). CONCLUSIONS: The observed difference in PRU between nonsmokers and current smokers is largely attributable to the difference in hemoglobin level. Enhanced clopidogrel responsiveness in cigarette smokers is not confirmed in this study and the concept of the smokers' paradox needs further validation.
OBJECTIVES: The authors performed this analysis to examine whether the enhanced clopidogrel responsiveness in current smokers is maintained after adjusting the influence of hemoglobin on VerifyNow P2Y12 reaction unit (PRU). BACKGROUND: PRU is consistently reported to be lower in current smokers. However, PRU has a significant inverse relationship with hemoglobin level, and smokers have higher hemoglobin levels. Because the association between PRU and hemoglobin is likely to be an in vitro phenomenon, we hypothesized that the observed difference in PRU between nonsmokers and current smokers is the result of confounding effect of hemoglobin rather than true difference in platelet reactivity. METHODS: Three cohorts were combined for the analysis (SNUBH [Seoul National University Bundang Hospital], n = 459; CILON-T [influence of CILostazol-based triple antiplatelet therapy ON ischemic complication after drug-eluting stenT implantation], n = 715; HOST-ASSURE [Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen], n = 1,357). The final combined cohort consisted of 1,314 patients who underwent percutaneous coronary intervention and had VerifyNow P2Y12 assay results. General linear model (analysis of covariance) was used to control the effect of hemoglobin on PRU. RESULTS: A significant inverse correlation was observed between PRU and hemoglobin (r = -0.389; p < 0.001). Current smokers showed a significantly higher hemoglobin level (13.5 ± 1.6 vs. 14.4 ± 1.5; p < 0.001) but lower PRU level (230.1 ± 90.7 vs. 212.2 ± 83.6; p < 0.001). After adjusting the influence of hemoglobin on PRU, there was no difference in PRU between nonsmokers and current smokers (224.1 [95% confidence interval: 218.7 to 229.5] vs. 225.3 [95% confidence interval: 217.2 to 233.3]; p = 0.813). CONCLUSIONS: The observed difference in PRU between nonsmokers and current smokers is largely attributable to the difference in hemoglobin level. Enhanced clopidogrel responsiveness in cigarette smokers is not confirmed in this study and the concept of the smokers' paradox needs further validation.
Authors: Matthias Bossard; Christopher B Granger; Jean-Francois Tanguay; Gilles Montalescot; David P Faxon; Sanjit S Jolly; Petr Widimsky; Kari Niemela; Philippe Gabriel Steg; Madhu K Natarajan; Peggy Gao; Keith A A Fox; Salim Yusuf; Shamir R Mehta Journal: J Am Heart Assoc Date: 2017-11-03 Impact factor: 5.501
Authors: Jae Min Kim; Jin Sug Kim; Hyung Oh Kim; So Ra Lee; Jae Hwan Rhew; Jong Shin Woo; Jang Hyun Cho; Kyung Hwan Jeong; Weon Kim Journal: Medicine (Baltimore) Date: 2020-03 Impact factor: 1.817