The Effects of Antipsychotic Treatment on Presynaptic Dopamine Synthesis Capacity in First-Episode Psychosis: A Positron Emission Tomography Study.
Biol Psychiatry
; 85(1): 79-87, 2019 01 01.
Article
in En
| MEDLINE
| ID: mdl-30122287
ABSTRACT
BACKGROUND:
Elevated striatal dopamine synthesis capacity has been implicated in the etiology and antipsychotic response in psychotic illness. The effects of antipsychotic medication on dopamine synthesis capacity are poorly understood, and no prospective studies have examined this question in a solely first-episode psychosis sample. Furthermore, it is unknown whether antipsychotic efficacy is linked to reductions in dopamine synthesis capacity. We conducted a prospective [18F]-dihydroxyphenyl-L-alanine positron emission tomography study in antipsychotic naïve/free people with first-episode psychosis commencing antipsychotic treatment.METHODS:
Dopamine synthesis capacity (indexed as influx rate constant) and clinical symptoms (measured using Positive and Negative Syndrome Scale) were measured before and after at least 5 weeks of antipsychotic treatment in people with first-episode psychosis. Data from a prior study indicated that a sample size of 13 would have >80% power to detect a statistically significant change in dopamine synthesis capacity at alpha = .05 (two tailed).RESULTS:
A total of 20 people took part in the study, 17 of whom were concordant with antipsychotic medication at therapeutic doses. There was no significant effect of treatment on dopamine synthesis capacity in the whole striatum (p = .47), thalamus, or midbrain, nor was there any significant relationship between change in dopamine synthesis capacity and change in positive (ρ = .35, p = .13), negative, or total psychotic symptoms.CONCLUSIONS:
Dopamine synthesis capacity is unaltered by antipsychotic treatment, and therapeutic effects are not mediated by changes in this aspect of dopaminergic function.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Psychotic Disorders
/
Antipsychotic Agents
/
Dopamine
/
Neostriatum
/
Corpus Striatum
Type of study:
Observational_studies
/
Prognostic_studies
Limits:
Adult
/
Female
/
Humans
/
Male
Language:
En
Journal:
Biol Psychiatry
Year:
2019
Document type:
Article
Affiliation country:
United kingdom