Lead Exposure Linked With Long-Term Cognitive Decline
Lead exposure is relatively common today, and the results of this study are no surprise. What this article does support is the identification of patients with high lead levels and chelation therapy to rid the body of this lead excess if found. Hair analysis is still one of the most effective, cheapest and easiest method I’ve come across to determine heavy metal exposure. What is stunning in this article is that the author suggests that much of what we term “age related cognitive decline” may actually be from lead exposure.
Neurology 2000;55:1144-1150 Cognitive function continues to decline in older adults years after occupational exposure to lead ends, report researchers in the October 24th issue of Neurology. “Former lead workers exhibited greater annual declines in adjusted test scores than did controls for 17 of 19 cognitive tests,” the investigators write. These reached significance for the Rey complex figure copy test, and the Rey auditory verbal learning test for immediate recall and recognition. Former lead workers also exhibited significantly greater age-related annual declines for four cognitive tests: block design, digit symbol, serial digit learning, and finger tapping non-dominant hand tests. Annual declines were larger with increasing peak tibia lead levels, though not for baseline blood lead levels. “An increase of 15.7 mcg/g of peak tibia lead was equivalent in its effects on annual test decline to 5 more years of age at the baseline visit,” the investigators write. “Some of what we have been calling ‘normal aging’ may in fact be due to past exposures to chemicals or other agents that can affect the central nervous system,” Dr. Schwartz commented in an American Academy of Neurology statement. “This is potentially a very important health problem.”