Posted on May 06, 2014, 6 a.m.
Exposure to very low levels of ambient lead in the air may raise the risk of conversion of mild cognitive impairment to Alzheimer’s Disease.
Mounting evidence suggests that air pollution may be an underrecognized contributor to chronic diseases – most notably, cardiovascular, and death. Lead, present in air pollution. is known to be toxic to the neurological system. Linda Mah, from the University of Toronto (Canada), and colleagues analyzed data collected in the Alzheimer’s Disease Neuroimaging Initiative (ADNI), involving 265 older men and women, ages 55 to 90 years, with amnestic mild cognitive impairment (aMCI) – characterized by subjective and objective memory loss during activities of daily living. The team revealed that even exposure to very low levels of ambient lead appeared to increase the risk for conversion from amnestic mild cognitive impairment to Alzheimer's Disease. Further analysis showed that lead exposure also significantly predicted atrophy of the hippocampus, as well as entorhinal cortex atrophy and thickness reduction. The study authors warn that: “These findings suggest ambient lead exposure is associated with greater risk of [Alzheimer’s Disease] and AD-related neuroimaging abnormalities in [amnestic mild cognitive impairment], and extend the growing body of literature suggesting neurotoxic effects may occur even with very low levels of lead exposure.”
Mah L. Presentation at American Association for Geriatric Psychiatry (AAGP) 2014 Annual Meeting, 18 March 2014.