Two weeks' quetiapine treatment for schizophrenia, drug-induced psychosis and borderline personality disorder: a naturalistic study with drug plasma levels.
OBJECTIVE
To evaluate clinical outcomes and the tolerability of 2 weeks' quetiapine (QTP) treatment for hospitalised patients in a naturalistic setting.


METHODS
Patients with schizophrenia (n = 18), drug-induced psychosis (n = 10; 3 cocaine, 4 hashish and marijuana, and 3 all three substances) or borderline personality disorder (n = 13), were diagnosed by two expert clinicians on the basis of an unstructured clinical interview, and were treated with QTP (250-1000 mg/day). The subjects were then clinically assessed at baseline, and after 7 and 15 days, using the Brief Psychiatric Rating Scale, the Positive and Negative Symptoms Scale (PANSS) and the Hamilton Rating Scale for Depression. At the end of the study, plasma QTP levels were determined and examined in relation to clinical outcome and tolerability.


RESULTS
The mean scores of each rating scale were significantly lower at the end of the study in the population as a whole, and within each diagnostic group. The percentage improvement was significantly greater in the patients with drug-induced psychosis than in those with schizophrenia (42.4 +/- 9.1% versus 23.6 +/- 13.5%). QTP was well tolerated, and the incidence of extrapyramidal side effects was low. There was a linear correlation between plasma levels and dose/kg of QTP (r = 0.31; p < 0.05). The improvement in PANSS significantly correlated with plasma levels and dose/kg in each diagnostic category (Spearman's coefficient was 0.75 [p < 0.01] for schizophrenia and borderline personality disorder, and was 0.68 [p < 0.05] for drug-induced psychosis).


CONCLUSIONS
The results suggest that 2 weeks' QTP treatment may improve the clinical outcome of psychotic re-exacerbation phases in different diagnostic categories and indicate that QTP improves clinical outcome in drug-induced psychosis, as QTP levels correlated with the clinical improvement measured by PANSS.
Mauri
Massimo C
MC
University of Milan, Clinical Psychiatry Department, Clinical Neuropsychopharmacology Unit, Fondazione IRCCS Ospedale Maggiore, Milan, Italy.
Volonteri
Lucia S
LS
Fiorentini
Alessio
A
Pirola
Rodolfo
R
Bareggi
Silvio R
SR
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001883:Borderline Personality Disorder / Q000097:blood* / Q000188:drug therapy / Q000523:psychology; D003987:Dibenzothiazepines / Q000097:blood* / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011605:Psychoses, Substance-Induced / Q000097:blood* / Q000188:drug therapy / Q000523:psychology; D000069348:Quetiapine Fumarate; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy; D013997:Time Factors
D003987:Dibenzothiazepines; D000069348:Quetiapine Fumarate