Bruce J. Kinon

OBJECTIVE: Research and clinical translation in schizophrenia is limited by inconsistent definitions of treatment resistance and response. To address this issue, the authors evaluated current approaches and then developed consensus criteria and guidelines. METHOD: A systematic review of randomized antipsychotic clinical trials in treatment-resistant schizophrenia was performed, and definitions of treatment resistance were extracted. Subsequently, consensus operationalized criteria were developed through 1) a multiphase, mixed methods approach, 2) identification of key criteria via an online survey, and 3) meetings to achieve consensus. RESULTS: Of 2,808 studies identified, 42 met inclusion criteria. Of these, 21 studies (50%) did not provide operationalized criteria. In the remaining studies, criteria varied considerably, particularly regarding symptom severity, prior treatment duration, and antipsychotic dosage thresholds; only two studies (5%) utilized the same criteria. The consensus group identified minimum and optimal criteria, employing the following principles: 1) current symptoms of a minimum duration and severity determined by a standardized rating scale; 2) moderate or worse functional impairment; 3) prior treatment consisting of at least two different antipsychotic trials, each for a minimum duration and dosage; 4) systematic monitoring of adherence and meeting of minimum adherence criteria; 5) ideally at least one prospective treatment trial; and 6) criteria that clearly separate responsive from treatment-resistant patients. CONCLUSIONS: There is considerable variation in current approaches to defining treatment resistance in schizophrenia. The authors present consensus guidelines that operationalize criteria for determining and reporting treatment resistance, adequate treatment, and treatment response, providing a benchmark for research and clinical translation.

OBJECTIVE: This study examined the pathomorphology of the caudate nuclei in first-episode schizophrenic patients with minimal previous neuroleptic exposure. METHOD: Magnetic resonance imaging (MRI) of the brain was used to examine longitudinally the caudate pathomorphology in 29 first-episode schizophrenic patients and 10 healthy comparison subjects. MRI scans were obtained after the subjects entered the study and at 18-month follow-up. The patients were treated with standardized neuroleptic regimens during the 18-month period. Volumetric assessments of the cerebral cortex, lateral ventricles, and caudate nuclei were performed on T1-weighted coronal brain sections. In addition, the patients were systematically evaluated for psychopathology at baseline and during treatment. RESULTS: Caudate volumes increased 5.7% in the patients during the 18-month treatment interval, whereas they decreased 1.6% in the comparison subjects over the same time period. Greater amounts of antipsychotic medication received by patients before the first scan and younger age at the time of the first scan were associated with larger increases in caudate volume. CONCLUSIONS: Caudate enlargement occurs early in the course of treatment in young first-episode schizophrenic patients. This may be a result of an interaction between neuroleptic treatment and the plasticity of dopaminergic neuronal systems in young patients.

BACKGROUND: Weight change and the weight-related health factors of nonfasting serum glucose, serum cholesterol, and diastolic blood pressure levels were analyzed in patients with DSM-III-R schizophrenia and related disorders who received treatment with olanzapine for up to 3 years, and comparisons were made to patients treated with haloperidol. Baseline body mass index (BBMI; kg/m2) and dose (mg/day) were investigated as predictors of long-term weight change experienced during olanzapine treatment. METHOD: This analysis retrospectively examined 573 patients receiving olanzapine and 103 patients receiving haloperidol for 39 weeks or more from a study of 1,996 patients randomly assigned 2:1 to either olanzapine, 5 to 20 mg/day, or haloperidol, 5 to 20 mg/day. After 6 weeks of acute therapy, patients continued for 1 year or more with either double-blind or open-label olanzapine therapy or double-blind haloperidol therapy. RESULTS: Mean weight gain for olanzapine-treated patients observed for a median of 2.54 years trended toward a plateau after the first 39 weeks of treatment with a last-observation-carried-forward mean weight change of 6.26 kg (13.8 lb) and a median of 5.90 kg (13.0 lb). This was significantly higher than that for haloperidol-treated patients, whose mean weight gain was 0.69 kg (1.5 lb) after 1.15 years (p < .001). Patients with higher BBMI (> 27.6) gained significantly less weight during treatment with olanzapine than their lighter counterparts (BBMI < 27.6) (p < .001). The effect of olanzapine dose on weight was not significant (p > or = . 183). Median serum glucose at endpoint was not significantly associated (p = .096) with weight change for olanzapine. Median serum cholesterol and diastolic blood pressure for olanzapine-treated patients at endpoint showed a relationship with weight change that was statistically (p < or = .001) but not clinically significant. The difference in incidence of elevated serum glucose, cholesterol, or diastolic blood pressure between olanzapine and haloperidol therapy groups was not different (p > .05). CONCLUSION: Mean weight gain during olanzapine treatment trended toward a plateau after the initial 39 weeks of treatment with no further significant gain out to 3 years. Higher BBMI was predictive of a lower long-term weight gain, while dose was not a significant predictor of greater longer term weight change. The relationship between weight change and glucose was not statistically significant. The association between weight change and changes in cholesterol as well as changes in diastolic blood pressure was statistically significant but not considered clinically relevant based on the ranges observed.