O-NE005. Electroneuromyography as a predictor of peripheral neuropathy symptoms after two years follow-up in farmers exposed to pesticide: A cohort study

Abstract

Introduction . Farmer is one of the most common occupation in Indonesia. To increase crop production, they tend to use organophosphate or carbamate pesticides. These extensive pesticide uses could cause low cholinesterase levels in blood, and cause injury in peripheral nerve and neuropathy symptoms. With electroneuromyography (ENMG), subclinical neuropathy preceding its symptom could be found. The purpose of this study is to find association between any abnormality measurement in ENMG with neuropathic symptoms after two years. Methods . This was cohort prospective study. Farmers with history of pesticide exposure, without neuropathic symptoms in 2017, had low blood cholinesterase levels, and gave consent to have ENMG examination were recruited. Motor and sensory aspect of nerve was examined. For motor, we examined distal latency (DL), nerve conduction velocity (NCV), proximal amplitude (PA) and distal amplitude (DA) of median, ulnar, and tibial nerves. For sensory, we examined DL and PA of median, ulnar, and sural nerves. Neuropathic symptoms in 2 years follow up were determined from Total Neuropathic Symptoms Scale, with score > 0 diagnosed as having neuropathic symptoms. Results . There were 26 farmers included in this study. After statistical analyses, there were association between neuropathic symptoms after 2 years with motor NCV, motor PA and sensory DL of median nerve; motor NCV and motor PA of ulnar nerve (p-value > 0.05). After age, gender, working hour, pesticide spray duration adjustment, ENMG markers which had significant and independent association with neuropathy symptoms after two years were ulnar motor DL (p-value: 0.032), median motor NCV (p-value: 0.035), median motor PA (p-value: 0.043), and ulnar sensory DL (p-value: 0.010). Conclusion . From this study, we concluded that ENMG can be used as predictor for neuropathic symptoms in 2 years for asymptomatic farmers exposed to pesticide with low blood cholinesterase levels.