Antipsychotics, dopamine D2 receptor occupancy and clinical improvement in schizophrenia: A meta-analysis
Schizophrenia Research, 07/17/2012
Evidence Based Medicine
Yilmaz Z et al. – The results suggest that D2 occupancy is a contributing factor for the mechanism of antipsychotic effect in schizophrenia for some but not all antipsychotic medications.Methods
- Using the keywords “dopamine D2 receptor occupancy,” “schizophrenia,” “PET/SPECT” and “antipsychotics,” and further refining the authors' search to journal articles with information on % striatal D2 occupancy and % change in clinical symptoms as indexed by either the BPRS or the PANSS, the authors' final analysis consisted of 16 imaging studies (20 cohorts; N=206).
- The first step of the meta–analysis confirmed the positive relationship between antipsychotic medication and clinical improvement in SCZ (ES=1.36; 95% CI: 1.13–1.60).
- The second step of the authors’ analysis revealed that when D2 occupancy was limited to less than 80% in order to control for the appearance of extrapyramidal symptoms, high D2 occupancy was correlated with reduction in clinical scores (r=0.4, p<0.001) for medications other than clozapine or quetiapine.