Structural MRI and Cognitive Correlates in Pest-Control Personnel from Gulf War I

摘要

Acetylcholinesterase (AChE) inhibitors including organophosphate (OP) pesticides are known to produce chronic neurological symptoms at sufficient exposures. Our previous study of cognitive functioning in military pesticide applicators from GWI, found that veterans classified as higher pesticide-exposed reported significantly more health symptoms and performed less well on cognitive testing than lower-exposed veterans. It was the goal of this follow-up neuroimaging study to identify the relationships between OP pesticides, brain imaging, cognitive functioning and health symptoms in this well-characterized group of pest-control personnel from GWI. It was hypothesized that GWI veterans with higher levels and more exposures to AChE inhibiting pesticides and low-level nerve agents would show lower brain white matter volumes on MRI, report more health symptoms and perform less well on cognitive testing. Results showed that brain white matter volumes were significantly correlated with total health symptoms and with the attention/executive system domain and that cerebral and cerebellar white matter and gray matter volumes were significantly lower in veterans exposed to the OP dichlorvos (pest-strips) and the organochlorine lindane (delouser). Significant interaction effects were also found when comparing DEET and PB pills with hippocampal volumes and visual memory functioning resulting in lower volumes and worse memory function.