Abstract
Weight gain during pharmacological treatment is a well known phenomenon. Weight gain occurs during treatment with drugs of different chemical structures and is an important issue when patients are treated with antidepressants, antipsychotics or mood stabilizers [1], [2]. The clinical relevance of drug-induced weight gain includes increased rates of morbidity and reduced treatment compliance. Regarding the underlying causes, the important role of neurotransmitter systems has been discussed for decades. Particularly in the last decade, understanding of the regulation of appetite and weight has made major progress. In this context, the discovery of the adipose tissue hormone leptin, which signals the size of the peripheral fat stores to the central nervous system (CNS), was crucial [3]. Leptin is probably the most important peripheral signal for the long-term regulation of weight. In addition to the neuroendocrine systems, weight gain induced by psychotropic agents might also involve immune modulators such as tumournecrosis-factor-〈?(TNF-〈).
Some atypical antipsychotics appear to display a high propensity to induce glucose dysregulation and dyslipidemia. Convergent evidence suggests a hierarchy in the magnitude of body weight gain that may be induced by diverse agents, being: very high for clozapine and olanzapine; high for quetiapine, zotepin, chlorpromazine, and thioridazine; moderate for risperidone and sertindole; and low for ziprasidone, amisulpride, haloperidol, fluphenazine, pimozide and molindone [4]. The majority of studies dealing with antipsychotic-induced weight gain hypothesize that there is a limited period of weight gain. In contrast we suggest that psychotropic drugs, especially novel antipsychotics, can cause long-term weight gain. We present a case of risperidone-induced long-term weight gain.
A 35-year-old male Russian patient (body weight 94 kg, BMI = 28.7 kg/m2) with schizophrenia (meeting ICD-10 criteria) was admitted to our outpatient clinic in 1996. The electrocardiogram, electroencephalogram, blood tests and CT of the brain revealed no abnormal findings. Due to persisting psychotic symptoms, antipsychotic pharmacotherapy with 4 mg risperidone daily was started
After a few weeks the patient developed ‘carbohydrate craving’ and his eating behaviour changed. He complained about persistant hunger and gained weight up to a total body weight of 121 kg (BMI = 36.9 kg/m2) within 2 years. Blood tests revealed elevated lipid and glucose levels. Nutritional advice (moderately high-carbohydrate and low-fat meals) and regular physical exercise had no influence on the weight gain. The risperidone therapy was discontinued and he was switched to amisulpride, losing 3 kg body weight.
We hypothesize that risperidone induced the excessive long-term weight gain. Further studies are needed to elucidate the underlying mechanisms of body weight gain during antipsychotic drug administration.