Katrin Lotan1, Uri Goldbourt1, Yariv Gerber2. 1. Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel. 2. Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel. Electronic address: yarivg@post.tau.ac.il.
Abstract
OBJECTIVES: We evaluated long-term incidence of cancer after myocardial infarction among current, former, and never smokers, and assessed whether reducing cigarette consumption is associated with decreased cancer risk. METHODS: Consecutive patients aged ≤65 years discharged from 8 hospitals in central Israel after first myocardial infarction in 1992-1993 were followed for cancer and death. Extensive data including smoking habits were obtained at the index hospitalization and 4 time points during follow-up. Survival methods were applied to assess the hazard ratios (HRs) for cancer associated with smoking categories. RESULTS: Included in the study were 1486 cancer-free participants (mean age, 54 years; 81% men), among whom 787 were current smokers at baseline (average daily cigarette consumption = 29). Smokers were younger than nonsmokers and more likely to be male and of lower socioeconomic status. Over a median follow-up of 21.4 years, 273 (18.4%) patients developed cancer. Baseline smoking was associated with a ∼40% excess adjusted risk of cancer; ∼25% after accounting for death as a competing event. Considering changes in smoking during follow-up, the excess risk was confined to persistent smokers (adjusted HR 1.75; 95% confidence interval [CI], 1.22-2.50), whereas post- (HR 1.14; 95% CI, 0.80-1.62) and pre-myocardial infarction quitters (HR 1.02; 95% CI, 0.71-1.47) were comparable with never smokers. Among persistent smokers, each reduction of 10 cigarettes relative to pre-myocardial infarction consumption was associated with a ∼10% reduced adjusted risk. CONCLUSION: Among young survivors of first myocardial infarction followed-up longitudinally, smoking cessation is associated with lower risk of cancer. Reducing consumption among smokers may also be beneficial.
OBJECTIVES: We evaluated long-term incidence of cancer after myocardial infarction among current, former, and never smokers, and assessed whether reducing cigarette consumption is associated with decreased cancer risk. METHODS: Consecutive patients aged ≤65 years discharged from 8 hospitals in central Israel after first myocardial infarction in 1992-1993 were followed for cancer and death. Extensive data including smoking habits were obtained at the index hospitalization and 4 time points during follow-up. Survival methods were applied to assess the hazard ratios (HRs) for cancer associated with smoking categories. RESULTS: Included in the study were 1486 cancer-free participants (mean age, 54 years; 81% men), among whom 787 were current smokers at baseline (average daily cigarette consumption = 29). Smokers were younger than nonsmokers and more likely to be male and of lower socioeconomic status. Over a median follow-up of 21.4 years, 273 (18.4%) patients developed cancer. Baseline smoking was associated with a ∼40% excess adjusted risk of cancer; ∼25% after accounting for death as a competing event. Considering changes in smoking during follow-up, the excess risk was confined to persistent smokers (adjusted HR 1.75; 95% confidence interval [CI], 1.22-2.50), whereas post- (HR 1.14; 95% CI, 0.80-1.62) and pre-myocardial infarction quitters (HR 1.02; 95% CI, 0.71-1.47) were comparable with never smokers. Among persistent smokers, each reduction of 10 cigarettes relative to pre-myocardial infarction consumption was associated with a ∼10% reduced adjusted risk. CONCLUSION: Among young survivors of first myocardial infarction followed-up longitudinally, smoking cessation is associated with lower risk of cancer. Reducing consumption among smokers may also be beneficial.