title: Onset of grip- and pinch-strength impairment after acute poisonings with organophosphate insecticides.
abstract: The course of organophosphate-induced delayed polyneuropathy (OPIDP) in humans has not been quantitatively measured in epidemiologic studies. This study evaluated the association of acute OP poisonings with motor neurologic impairment. Hand grip and pinch strength were evaluated among 62 Nicaraguan men hospitalized for acute OP poisoning between 1992 and 1996; 39 cattle ranchers and fishermen who had never experienced pesticide poisoning were controls. Exposure categories were moderate and severe poisonings with neuropathic and non-neuropathic OPs. Strength was measured at hospital discharge and seven weeks after poisoning. Grip and pinch strength were impaired among all OP-poisoned subjects at both examinations, more noticeably among those poisoned with OPs with suspected neuropathic effects, methamidophos and chlorpyrifos. In those with severe poisonings with neuropathic OPs, impairments were more marked among intentional than among occupational poisonings. The performances of suicidal subjects worsened at the second examination, consistent with OPIDP. Early motor impairment at the time of hospital discharge is consistent with cholinergic depolarization blockade after acute poisoning. The persistence of deficits in motor strength in all severely poisoned patients regardless of pesticide type was unexpected, and may reflect persistent cholinergic blockade or intermediate syndrome, neuropathy, or a combination of these.
authors.affiliation: Department of Physiology, National Autonomous University, León, Nicaragua. jamilette.miranda@smd.sll.se
authors.forename: Jamilette
authors.initials: J
authors.lastname: Miranda
authors.forename: Ingvar
authors.initials: I
authors.lastname: Lundberg
authors.forename: Rob
authors.initials: R
authors.lastname: McConnell
authors.forename: Edgar
authors.initials: E
authors.lastname: Delgado
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cuadra
authors.forename: Edmundo
authors.initials: E
authors.lastname: Torres
authors.forename: Catharina
authors.initials: C
authors.lastname: Wesseling
authors.forename: Matthew
authors.initials: M
authors.lastname: Keifer
mesh_terms: D000293:Adolescent; D000328:Adult; D018737:Hand Strength; D006801:Humans; D007306:Insecticides / Q000506:poisoning*; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000139:chemically induced*; D016273:Occupational Exposure; D009943:Organophosphorus Compounds; D013406:Suicide, Attempted; D013997:Time Factors
chemical_list: D007306:Insecticides; D009943:Organophosphorus Compounds