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Environmental lead exposure and cognitive function in community-dwelling older adults
R A Shih1, T A Glass, K Bandeen-Roche
1Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
Neurology
|September 15, 2006
Summary
Long-term environmental lead exposure is linked to cognitive decline in older adults. Cumulative lead in the tibia, but not blood lead, was associated with poorer performance across multiple cognitive domains.
Area of Science:
- Environmental Health
- Neuroscience
- Gerontology
Background:
- Lead exposure is a significant public health concern.
- Cognitive decline is a common issue in aging populations.
- The long-term impact of cumulative lead exposure on cognition requires further investigation.
Purpose of the Study:
- To investigate the association between long-term environmental lead exposure and cognitive function in older Americans.
- To differentiate the effects of recent versus cumulative lead exposure on cognitive abilities.
Main Methods:
- Cross-sectional analysis of 991 community-dwelling adults aged 50-70.
- Multiple linear regression used to assess lead dose (blood and tibia) and cognitive function.
- Tibia lead measured via X-ray fluorescence; seven cognitive domains assessed.
Main Results:
- Higher tibia lead levels correlated with worse cognitive function across all seven domains.
- No significant association found between blood lead levels and cognitive function.
- Associations between tibia lead and cognition were partially attenuated by education, wealth, and race/ethnicity.
Conclusions:
- Cumulative lead exposure from past environmental sources may have lasting negative effects on cognitive function.
- Earlier lead exposure could contribute to age-related cognitive decrements in older adults.
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