Factors associated with weight gain during olanzapine treatment in patients with schizophrenia or bipolar disorder: results from a six-month prospective, multinational, observational study.

The aim of this 6-month observational study was to examine which clinical, eating- and lifestyle-related factors were associated with weight gain in patients initiating or switching to oral olanzapine for the treatment of schizophrenia or bipolar mania. A total of 622 outpatients in four countries (China, Mexico, Romania, Taiwan) were assessed at monthly intervals for up to 6 months. Mixed model repeated-measures analysis, adjusted for baseline weight, was used to identify which factors were associated with weight gain during olanzapine therapy. After 6 months of therapy, the LS mean weight change was +4.1 kg and 43.9% of the patients had significant (> or = 7%) weight gain. Early significant weight gain after 2 months of therapy occurred in 23.4% of the patients and these patients gained significantly more weight overall. Ten factors were associated with weight gain during 6 months of olanzapine therapy in an exploratory multivariate analysis: country, housing conditions, stronger appetite, excessive amount of food needed to feel full, eating until uncomfortably full, thoughts preoccupied with food, meal location, increased meal frequency, evening snack consumption, and a lower amount of vigorous exercise. These results indicate that the influence of environmental, eating- and lifestyle-related factors should be considered when assessing weight gain during olanzapine therapy.

Long-term antipsychotic monotherapy for schizophrenia: disease burden and comparative outcomes for patients treated with olanzapine, quetiapine, risperidone, or haloperidol monotherapy in a pan-continental observational study.

OBJECTIVE: Noninterventional, naturalistic studies facilitate examination of current clinical practices and provide an understanding of the impact of the biopsychosocial aspects of schizophrenia. This article describes disease burden and patient outcomes, with an emphasis on the comparative effectiveness and tolerability of antipsychotic monotherapy. METHOD: Outpatients initiating or changing antipsychotic therapy for DSM-IV- or ICD-10-defined schizophrenia (N = 7658) were allocated to olanzapine or nonolanzapine cohorts (November 2000 to December 2001). Treatment was at the psychiatrist's discretion, including flexible dosing and use of concomitant therapies and medications, with assessments at 0, 3, 6, 12, 18, 24, 30, and 36 months. Longitudinal clinical, pharmacologic, functional, and social data were collected over 36 months across 27 countries. RESULTS: At entry, 76% of patients were initiated/switched to antipsychotic monotherapy, most commonly with olanzapine (N = 3222), risperidone (N = 1117), quetiapine (N = 189), or haloperidol (N = 257). Patients prescribed olanzapine were more likely to maintain their baseline monotherapy (p < .001) and did so for a longer period (p < .001) compared with other antipsychotics. Median time to discontinuation (in months) was as follows: olanzapine 30.0, risperidone 23.1, quetiapine 13.9, haloperidol 12.5. Olanzapine-treated patients were also more likely to respond, and did so more rapidly than patients on other monotherapies (p < .001). Response data were also favorable for risperidone; median time to response (in months) was as follows: olanzapine 5.2, risperidone 6.3, quetiapine 11.3, haloperidol 11.7. Treatment-emergent adverse events varied: olanzapine patients had less favorable odds for significant weight gain (p < .001); haloperidol patients, for motor dysfunction (p < or = .002). CONCLUSION: These naturalistic data from less-studied outpatient communities highlight the variability in clinical and functional outcomes associated with long-term antipsychotic treatment.