ABSTRACT
OBJECTIVE: To determine if long-term exposure to high levels of lead in the environment is associated with decrements in cognitive ability in older Americans. METHODS: We completed a cross-sectional analysis using multiple linear regression to evaluate associations of recent (in blood) and cumulative (in tibia) lead dose with cognitive function in 991 sociodemographically diverse, community-dwelling adults, aged 50 to 70 years, randomly selected from 65 contiguous neighborhoods in Baltimore, MD. Tibia lead was measured with (109)Cd induced K-shell X-ray fluorescence. Seven summary measures of cognitive function were created based on standard tests in these domains: language, processing speed, eye-hand coordination, executive functioning, verbal memory and learning, visual memory, and visuoconstruction. RESULTS: The mean (SD) blood lead level was 3.5 (2.2) microg/dL and tibia lead level was 18.7 (11.2) microg/g. Higher tibia lead levels were consistently associated with worse cognitive function in all seven domains after adjusting for age, sex, APOE-epsilon4, and testing technician (six domains p Subject(s)
Bone and Bones/chemistry
, Cognition Disorders/diagnosis
, Environmental Exposure/adverse effects
, Lead Poisoning, Nervous System/diagnosis
, Lead/analysis
, Age Factors
, Aged
, Apolipoprotein E4/genetics
, Blood Chemical Analysis/standards
, Bone and Bones/drug effects
, Bone and Bones/metabolism
, Cognition Disorders/chemically induced
, Cognition Disorders/psychology
, Cohort Studies
, Cross-Sectional Studies
, Educational Status
, Female
, Humans
, Lead/blood
, Lead/toxicity
, Lead Poisoning, Nervous System/epidemiology
, Lead Poisoning, Nervous System/metabolism
, Male
, Mass Screening/methods
, Mass Screening/standards
, Middle Aged
, Neuropsychological Tests
, Observer Variation
, Predictive Value of Tests
, Sex Factors
, Socioeconomic Factors
, Spectrometry, X-Ray Emission/standards
, Tibia/chemistry
, Tibia/drug effects
, Tibia/metabolism