BACKGROUND: Previous analyses from the National Health and Nutrition Examination Survey (NHANES III) have found that elevated blood lead levels may be associated with cardiovascular mortality, cancer mortality, and all-cause mortality. The 5-aminolevulinic acid dehydratase (ALAD) G177C genetic polymorphism (rs 1800435) affects lead toxicokinetics and may alter the adverse effects of lead exposure. We examined whether the ALAD G177C single nucleotide polymorphism (SNP) affects the relationship between lead and mortality. METHODS: We analyzed a subset of 3349 genotyped NHANES III participants at least 40 years of age. Using Cox proportional hazards regression, we estimated the relative risk of all-cause, cardiovascular disease, and cancer mortality by ALAD genotype, and by blood lead levels (<5 μg/dL vs. ≥5 μg/dL). We also tested whether the ALAD genotype modified the relationship between blood lead level and mortality. RESULTS: The adjusted overall relative risk for participants with the variant ALAD genotype was decreased for all-cause mortality (hazards ratio = 0.68; [95% confidence interval = 0.50-0.93]) compared with persons having the common GG genotype. There was some suggestion that higher lead levels were associated with cancer mortality (1.48 [0.92-2.38]). We observed no convincing interaction effect between ALAD genotype and blood lead level on mortality risk. CONCLUSION: The ALAD genotype may be associated with decreased mortality from all causes and from cancer. This association does not seem to be affected by lead exposure.
BACKGROUND: Previous analyses from the National Health and Nutrition Examination Survey (NHANES III) have found that elevated blood lead levels may be associated with cardiovascular mortality, cancer mortality, and all-cause mortality. The 5-aminolevulinic acid dehydratase (ALAD) G177C genetic polymorphism (rs 1800435) affects lead toxicokinetics and may alter the adverse effects of lead exposure. We examined whether the ALAD G177C single nucleotide polymorphism (SNP) affects the relationship between lead and mortality. METHODS: We analyzed a subset of 3349 genotyped NHANES III participants at least 40 years of age. Using Cox proportional hazards regression, we estimated the relative risk of all-cause, cardiovascular disease, and cancer mortality by ALAD genotype, and by blood lead levels (<5 μg/dL vs. ≥5 μg/dL). We also tested whether the ALAD genotype modified the relationship between blood lead level and mortality. RESULTS: The adjusted overall relative risk for participants with the variant ALAD genotype was decreased for all-cause mortality (hazards ratio = 0.68; [95% confidence interval = 0.50-0.93]) compared with persons having the common GG genotype. There was some suggestion that higher lead levels were associated with cancer mortality (1.48 [0.92-2.38]). We observed no convincing interaction effect between ALAD genotype and blood lead level on mortality risk. CONCLUSION: The ALAD genotype may be associated with decreased mortality from all causes and from cancer. This association does not seem to be affected by lead exposure.
Authors: Janice Onuki; Célia Maria Rech; Marisa H G Medeiros; Gisela de A Umbuzeiro; Paolo Di Mascio Journal: Environ Mol Mutagen Date: 2002 Impact factor: 3.216
Authors: Man-Huei Chang; Mary Lou Lindegren; Mary A Butler; Stephen J Chanock; Nicole F Dowling; Margaret Gallagher; Ramal Moonesinghe; Cynthia A Moore; Renée M Ned; Mary R Reichler; Christopher L Sanders; Robert Welch; Ajay Yesupriya; Muin J Khoury Journal: Am J Epidemiol Date: 2008-10-20 Impact factor: 4.897
Authors: Xia Huo; Lin Peng; Bo Qiu; Liangkai Zheng; Taofeek Akangbe Yekeen; Xijin Xu Journal: Environ Sci Pollut Res Int Date: 2014-02-14 Impact factor: 4.223