title: Risk of death from cardiovascular disease associated with low-level arsenic exposure among long-term smokers in a US population-based study.
abstract: High levels of arsenic exposure have been associated with increases in cardiovascular disease risk. However, studies of arsenic's effects at lower exposure levels are limited and few prospective studies exist in the United States using long-term arsenic exposure biomarkers. We conducted a prospective analysis of the association between toenail arsenic and cardiovascular disease mortality using longitudinal data collected on 3939 participants in the New Hampshire Skin Cancer Study. Using Cox proportional hazard models adjusted for potential confounders, we estimated hazard ratios and 95% confidence intervals associated with the risk of death from any cardiovascular disease, ischemic heart disease, and stroke, in relation to natural-log transformed toenail arsenic concentrations. In this US population, although we observed no overall association, arsenic exposure measured from toenail clipping samples was related to an increased risk of ischemic heart disease mortality among long-term smokers (as reported at baseline), with increased hazard ratios among individuals with ≥ 31 total smoking years (HR: 1.52, 95% CI: 1.02, 2.27), ≥ 30 pack-years (HR: 1.66, 95% CI: 1.12, 2.45), and among current smokers (HR: 1.69, 95% CI: 1.04, 2.75). These results are consistent with evidence from more highly exposed populations suggesting a synergistic relationship between arsenic exposure and smoking on health outcomes and support a role for lower-level arsenic exposure in ischemic heart disease mortality.
authors.affiliation: Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA; Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY, USA.
authors.forename: Shohreh F
authors.initials: SF
authors.lastname: Farzan
authors.affiliation: Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.
authors.forename: Judy R
authors.initials: JR
authors.lastname: Rees
authors.affiliation: Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.
authors.forename: M Scot
authors.initials: MS
authors.lastname: Zens
authors.affiliation: Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA. Electronic address: margaret.r.karagas@dartmouth.edu.
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Karagas
mesh_terms: D000328:Adult; D000368:Aged; D001151:Arsenic / Q000032:analysis*; D015415:Biomarkers; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000401:mortality*; D004781:Environmental Exposure / Q000032:analysis*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000401:mortality; D009262:Nails / Q000737:chemistry*; D011446:Prospective Studies; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology; D012907:Smoking / Q000453:epidemiology*; D012959:Socioeconomic Factors; D014481:United States
chemical_list: D015415:Biomarkers; D001151:Arsenic
keywords: Arsenic; Cardiovascular disease; Ischemic heart disease; Mortality; New Hampshire; Smoking