[Schizophrenia and diabetes mellitus: not an improbable combination]

Three male schizophrenia patients, aged 41, 40 and 61 years respectively, who had undergone treatment without a satisfactory result, were treated with the antipsychotic clozapine. Diabetes mellitus developed within a period of several months to several years. The antipsychotic medication could be continued once the patients had been started on blood-glucose lowering medication. There seems to be an increased incidence of type-2 diabetes mellitus in patients with schizophrenia. It has been suggested that treatment with neuroleptics, especially atypical neuroleptics, provokes the onset of diabetes mellitus. The relatively young age (often < 50 years) at onset is a cause for concern. From a pathophysiological viewpoint, an increased prevalence of diabetic risk factors has been suggested for schizophrenia in addition to the toxic effect of neuroleptics in general. The possible consequences for the general health of this vulnerable group of patients warrant recommendations concerning the regular monitoring of these patients during treatment.