Reasons and outcomes of olanzapine dose adjustments in the outpatient treatment of schizophrenia.
BACKGROUND
Antipsychotic treatment dose adjustments may influence treatment outcomes in patients with schizophrenia.


METHODS
We analysed data from 4,247 outpatients with schizophrenia who started olanzapine monotherapy in the 3-year, prospective, observational SOHO study to determine factors associated with olanzapine dose adjustments and how these impact on treatment effectiveness and tolerability.


RESULTS
Regression analyses showed an association between changes in the Clinical Global Impression (CGI) and olanzapine dose changes: patients with a lack of effectiveness were more likely to have their dose increased, whereas patients with good treatment response were more likely to have a dose decrease. Improvement in tardive dyskinesia was associated with dose increase or no change (p=0.034) and worsening of sexual problems was associated with dose decrease (p=0.001). Conversely, an increase in olanzapine dose was associated with subsequent clinical improvement (CGI), but dose adjustment had no significant effects on tolerability outcomes.


CONCLUSIONS
These results indicate that psychiatrists tend to modify olanzapine dose according to treatment response. Dose increases seem to be associated with a better response to treatment and not with a worsening of side-effects.
Suarez
D
D
Sant Joan de Déu-SSM, Fundació Sant Joan de Déu, CIBER Salud Mental (Instituto de Salud Carlos III), Sant Boi de Llobregat, Barcelona, Spain. david.suarez.lamas@gmail.com
Haro
J M
JM
Novick
D
D
Perrin
E
E
Ochoa
S
S
Naber
D
D
D000328:Adult; D000553:Ambulatory Care; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D020820:Dyskinesias / Q000188:drug therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D016017:Odds Ratio; D000077152:Olanzapine; D011446:Prospective Studies; D012044:Regression Analysis; D012559:Schizophrenia / Q000188:drug therapy*; D012735:Sexual Dysfunction, Physiological / Q000139:chemically induced; D016896:Treatment Outcome
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D000077152:Olanzapine