title: Association between low-level environmental arsenic exposure and QT interval duration in a general population study.
abstract: High-level arsenic exposure is consistently associated with QT prolongation, a risk factor for arrhythmia and sudden cardiac death. Arsenic may act on QT by increasing cardiac calcium currents. The authors hypothesized that low-level arsenic exposure would be associated with QT duration and that this effect would be stronger among persons not using calcium channel blockers. They performed a cross-sectional analysis in elderly men from the Normative Aging Study to analyze associations between toenail arsenic and QT and heart rate-corrected QT (QTc) durations and to examine effect modification by calcium channel blocker use, using linear regression and adjusting for potential confounders. Participants were examined in Boston, Massachusetts, between 2000 and 2002 or in 2006. An interquartile range increase in arsenic concentration was associated with a 3.8-millisecond increase in QT (95% confidence interval: 0.82, 6.8) and a 2.5-millisecond increase in QTc (95% confidence interval: 0.11, 4.9). There was no evidence of effect modification by medication use for either QT (P = 0.93) or QTc (P = 0.58). The authors observed positive associations between a biomarker of arsenic exposure and QT duration but found no evidence of effect modification by calcium channel blocker use, possibly because of modest power.
authors.affiliation: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina 27599-7435, USA. irinam@email.unc.edu
authors.forename: Irina
authors.initials: I
authors.lastname: Mordukhovich
authors.forename: Robert O
authors.initials: RO
authors.lastname: Wright
authors.forename: Chitra
authors.initials: C
authors.lastname: Amarasiriwardena
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Baja
authors.forename: Andrea
authors.initials: A
authors.lastname: Baccarelli
authors.forename: Helen
authors.initials: H
authors.lastname: Suh
authors.forename: David
authors.initials: D
authors.lastname: Sparrow
authors.forename: Pantel
authors.initials: P
authors.lastname: Vokonas
authors.forename: Joel
authors.initials: J
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000453:epidemiology; D001151:Arsenic / Q000032:analysis / Q000633:toxicity*; D001152:Arsenicals / Q000009:adverse effects*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D016757:Death, Sudden, Cardiac / Q000453:epidemiology; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D008133:Long QT Syndrome / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009262:Nails / Q000737:chemistry; D012044:Regression Analysis; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology
chemical_list: D001152:Arsenicals; D002121:Calcium Channel Blockers; D001151:Arsenic
references.citation: Environ Res. 2006 Sep;102(1):125-39
references.pmid: 16442520
references.citation: Prog Cardiovasc Dis. 2001 Mar-Apr;43(5 Suppl 1):1-45
references.pmid: 11269621
references.citation: Environ Health Perspect. 2001 Jul;109(7):711-6
references.pmid: 11485870
references.citation: Br J Pharmacol. 2008 May;154(1):105-13
references.pmid: 18332854
references.citation: Lancet. 2002 Dec 14;360(9349):1903-13
references.pmid: 12493255
references.citation: Am J Epidemiol. 1985 Jul;122(1):51-65
references.pmid: 4014201
references.citation: Ann Noninvasive Electrocardiol. 2006 Oct;11(4):318-26
references.pmid: 17040280
references.citation: J Health Popul Nutr. 2006 Jun;24(2):221-7
references.pmid: 17195563
references.citation: Environ Health Perspect. 2008 Feb;116(2):158-64
references.pmid: 18288312
references.citation: Am J Epidemiol. 2000 Jul 1;152(1):84-90
references.pmid: 10901333
references.citation: Environ Health Perspect. 2007 May;115(5):690-4
references.pmid: 17520054
references.citation: Ann Intern Med. 2000 Dec 5;133(11):881-5
references.pmid: 11103058
references.citation: Gerontologist. 1966 Dec;6(4):179-84
references.pmid: 5342911
references.citation: Environ Health Perspect. 2005 Mar;113(3):304-9
references.pmid: 15743719
references.citation: Mol Pharmacol. 2004 Jul;66(1):33-44
references.pmid: 15213294
references.citation: South Med J. 1989 Dec;82(12):1557-60
references.pmid: 2595426
references.citation: Am J Cardiol. 2008 May 22;101(10A):75D-86D
references.pmid: 18474278
references.citation: J Emerg Med. 1985;3(3):221-5
references.pmid: 2869081
references.citation: J Environ Biol. 2007 Apr;28(2 Suppl):333-47
references.pmid: 17929749
references.citation: J Am Coll Cardiol. 2006 Jan 17;47(2):362-7
references.pmid: 16412861
references.citation: Circ J. 2006 Nov;70(11):1407-14
references.pmid: 17062962
references.citation: Semin Vasc Med. 2002 Aug;2(3):315-23
references.pmid: 16222621
references.citation: Blood. 2001 Jul 15;98(2):266-71
references.pmid: 11435292
references.citation: Curr Opin Genet Dev. 2007 Jun;17(3):213-21
references.pmid: 17467978
references.citation: Free Radic Biol Med. 1999 Mar;26(5-6):746-61
references.pmid: 10218665
references.citation: Blood. 2002 Sep 15;100(6):2249-52
references.pmid: 12200393
references.citation: Basic Clin Pharmacol Toxicol. 2006 Apr;98(4):381-8
references.pmid: 16623862
references.citation: Clin Chem. 2001 Mar;47(3):418-25
references.pmid: 11238291
references.citation: J Clin Oncol. 2003 Oct 1;21(19):3609-15
references.pmid: 14512391
references.citation: J Int Med Res. 2008 May-Jun;36(3):471-8
references.pmid: 18534128
references.citation: J Toxicol Environ Health A. 2007 Jan 15;70(2):148-58
references.pmid: 17365576
references.citation: Br Med Bull. 1993 Jul;49(3):679-99
references.pmid: 8221032
references.citation: Pacing Clin Electrophysiol. 1990 Feb;13(2):164-70
references.pmid: 1689832