It is possible that other classes of exposures might produce a similar constellation of symptoms. In short, there are unlikely to be many agents that would produce such similar effects in terms of both symptoms reported and symptoms and signs not present. Insofar as there is agreement between symptoms treated by stimulating the ACh system outside the PGW setting and symptoms reported by PGWV, a connection between ACh downregulation and illness is tentatively supported. Ill PGWV commonly report fatigue and muscle weakness, memory and cognitive problems, diarrhea, and sleep apnea. These data too are consistent with a possible role of ACh depression in illness in PGWV, as might be expected following AChE-inhibitor exposure.
Many studies are small and poorly controlled.
Those most affected may have selected themselves out of this field, through illness or intolerance. Such research is clearly needed. This is important information and would be useful to replicate a longer time after exposure. The findings would be still more useful if more specific information within symptom categories was also elicited. Also needed are additional studies of specific objective measures that may be changed in ill subjects with prior AChE-inhibitor exposure.