Therapeutic D2/3 receptor occupancies and response with low amisulpride blood concentrations in very late-onset schizophrenia-like psychosis (VLOSLP).
BACKGROUND No study has examined dopamine D₂/₃ receptor (D₂/₃R) availability in antipsychotic-free older patients with schizophrenia. METHODS We included patients with schizophrenia 50 years or older who were antipsychotic-free for at least 3 months. We compared non-displaceable binding potential (BPND) of [(11)C]-raclopride in the caudate, putamen, ventral striatum, and globus pallidus between patients and age- and sex-matched healthy controls. RESULTS Ten patients participated (antipsychotic-naive=4). No differences in BPND were found between patients and controls in any ROIs (F(1, 72)=.42, p=.52). CONCLUSION The preliminary results suggest no differences in D₂/₃R availability between antipsychotic-free older patients with schizophrenia and controls.