Use of 18 F-ASEM PET to determine the availability of the a7-nicotinic acetylcholine receptor in recent-onset psychosis

Abstract

Limited postmortem evidence suggests a diminished availability of the α7 -nicotinic acetylcholine receptor (α7-nAChR) in the hippocampus in psychosis. Methods: In this cross-sectional study, we used PET with 18 F-ASEM ( 18 F-JHU82132; 3-(1,4-diazabicyclo[3.2.2] nonan-4-yl)-6-[ 18 F]fluorodibenzo[b,d]thiophene 5,5-dioxide), a radiotracer targeting the α7-nAChR, to compare the binding of 18 F-ASEM in the hippocampus of individuals who had recent-onset psychosis with that in healthy controls. Results: Individuals with recent-onset psychosis (nonaffective psychosis or affective psychosis), particularly those with nonaffective psychosis, showed lower hippocampal binding of 18 F-ASEM than healthy controls. Among patients, lower binding was associated with lower performance in 2 cognitive domains after controlling for age. Conclusion: Low availability of the α7-nAChR in the hippocampus may be linked to recent-onset psychosis. Further study is needed to assess its clinical relationship to neuropsychiatric symptoms.