[Tardive dyskinesia induced by classical antipsychotic drugs: a Tunisian sample of schizophrenics]

Abstract

Introduction: The term tardive dyskinesia (TD) is used to describe abnormal movement, primarily associated with typical antipsychotic drugs, which are used to treat psychotic states such as schizophrenia. TD is characterised by repetitive involuntary purposeless muscle contractions that force parts of the body into abnormal, and sometimes painful, movements or postures. These movements are involuntary and are difficult or impossible to control. TD usually begins with the face, mouth, lips and tongue, and includes grimacing, lip-smacking, tongue movements and rapid blinking. It may also involve the rest of the body and produce involuntary gestures, tics and writhing movements. TD is severe physically and socially disabling. Schizophrenia is thought to be the psychiatric diagnosis the most frequently associated with TD.

Materials and methods: The purpose of this article is to study the characteristics of TD in a Tunisian sample of 157 schizophrenics. A variety of demographic and clinical information was obtained by a questionnaire. Diagnoses of schizophrenia and TD were determined by using DSM-VI-R criteria. TD was assessed using the Abnormal Involuntary Movements Scale (AIMS).

Results: The average age in this sample was 37 ± 6 years. The intermediate duration of evolution of the disease was 8 ± 3 years with a medium full number of hospitalizations of 4 ± 3. We found 58% of the paranoid sub-type. The intermediate duration of exposure to classical neuroleptics was 7 ± 3 years. The average of daily neuroleptic amount was 572.9 ± 145.3 equivalent milligrams of chlorpromazine. Extended release antipsychotics were used in 64.3% of cases, with fluphenazine deaconate in 90% and haloperidol deaconate in 10%. Anticholinergics were used by 74.5% of patients, with use of biperidene in 96% of cases. Therapeutic observance was good in 89.2% of patients. The prevalence of TD was an estimated 35%. The average of AIMS score was 17 ± 9, with a minimal score of 3 and a maximal one of 34. The distribution of patients according to severity found a prevalence of 52.7% of subjects with moderate TD, 38.2% with light TD and 9.1% with severe TD. The distribution of patients according to type, according to DSM-IV criteria, found 78.4% of cases with choreiform TD, 17.5% of cases with athetosic TD and 4.1% of cases with rhythmic TD. The intermediate duration of evolution of TD was estimated at 18 ± 6 months with a minimal duration of 3 months and a maximum of 72 months. The distribution of subjects according to duration of evolution of TD found that approximately three quarter of patients presented with TD that had evolved since one duration, lower or equal to one year. The average age of patients at the moment of installation of TD was estimated at 36 ± 6 years with 22 years as a minimal and 46 years as a maximal age. Among them, 81.8% of patients were aged over 30 at the time of the installation of TD.

Conclusion: The majority of patients with schizophrenia in Tunisia are still treated with typical antipsychotic drugs, and that's why the prevalence of TD remains relatively high.