Appropriate intervention strategies for weight gain induced by olanzapine: a randomized controlled study.

ABSTRACT

Weight gain induced by antipsychotics is the second most frequently given reason for noncompliance with pharmacologic therapy; excessive sedative effects rank first, with extrapyramidal side effects ranking third. Frequently, weight gain leads to inconsistent pharmacologic treatment; this exposes patients to the risk of recurrent symptoms. In fact, one of the key contributors to good clinical outcomes in schizophrenic patients is compliance with pharmacologic treatment. The goals of this study were to evaluate weight gain in a group of patients treated with olanzapine, diet modifications, and moderate physical activity and to compare the findings with those from a second group of patients who were given only olanzapine treatment. For 8 wk, investigators followed 2 groups of patients suffering from schizophrenia and hypomania in bipolar disorder, according to the nosographic criteria of The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). The first group (A) of 18 patients (9 female, 9 male) affected by manic episodes in bipolar disorder received olanzapine (10-20 mg/d), jogged lightly for 30 min 3 times a week, and complied with a diet that consisted of 500 kcal/d less than usual. The second group (B) of 10 patients (4 female, 6 male) with schizophrenia received only olanzapine (10-20 mg/d). All patients from both groups were weighed at the beginning of the observation period and weekly thereafter for 2 mo. After 2 mo of observation, group A showed a mean weight gain of 1.47 kg, whereas group B exhibited a mean weight gain of 3.5 kg; the difference between the 2 groups was almost 2 kg (P<.005). Group A showed a statistically significant reduction in weight gain compared with group B, clearly demonstrating the effectiveness of moderate physical activity and diet therapy in reducing weight gain in atypical antipsychotic treatment. Therefore, patient weight and body mass index must be monitored during the first weeks of antipsychotic treatment, with the goals of avoiding significant weight gain and treatment interruption.