Au cours de la dernière décennie, plusieurs études se sont intéressées aux posologies moyennes d’entretien dans le traitement de la schizophrénie. Ces doses semblent être influencées par une multitude de variables. Le but de ce travail est d’étudier les doses d’entretien des neuroleptiques dans une population maghrébine et d’étudier l’impact relatif des différentes variables rapportées dans la littérature sur ces doses.

C’est une étude ponctuelle incluant les patients souffrant de schizophrénie dont la dernière hospitalisation remonte à plus de six mois et dont le traitement est stable depuis au moins un mois. Les données ont été recueillies sur la base d’un entretien clinique et sur le dossier médical. Quatre-vingt-douze patients ont été inclus. Les deux tiers étaient de sexe masculin. L’âge moyen était de 42ans et les femmes avaient un pourcentage plus élevé, non statistiquement significatif, de schizophrénie résiduelle.

Les doses d’entretien retrouvées étaient de 662,4±659,73mg en équivalents chlorpromazine. Elles sont à la limite supérieure des recommandations apportées par le Patients Outcome Research Team (« PORT ») et se rapprochent des doses d’entretien retrouvées dans les populations asiatiques. Seuls la polythérapie, le nombre de psychotropes prescrits et la présentation des neuroleptiques semblent avoir une influence significative sur les doses d’entretien. Les deux premiers étaient associés à de fortes doses. Les neuroleptiques retard étaient, eux, associés à des doses plus faibles.

Il en ressort que les facteurs qui interfèrent le plus avec les posologies d’entretien sont des facteurs de prescription non inhérents au malade ou aux caractéristiques de sa maladie.

Much research work has been undertaken on antipsychotic doses in the maintenance treatment of schizophrenia. Researchers found that these doses were likely to be influenced by a multitude of variables such as age, gender, duration of the disease and treatment, history of violent behaviours, potency of the neuroleptic drug, addiction and pattern of prescription. Few works have studied all the variables simultaneously, all the more so, since some of the variables cited above seem to be interdependent. The aim of this work is to study the mean antipsychotic doses in maintenance treatment of patients suffering from schizophrenia, who are considered as stabilized, and to study the relative effect of all the variables reported in the literature.

This is a transversal study which covered all the out-patients suffering from schizophrenia (referred to the DSM-IV) followed by the “Psy F” service in Razi hospital (Tunisia). Patients included in the study were those who had a stable maintenance dose in the previous month and whose last hospitalisation dated back to at least six months. All the patients were evaluated by the BPRS scale and data were collected from their medical history and by a clinical interview (clinical, demographic and therapeutic data). Data were computerized using Epi Info.6. A value of P below 0.001 was considered as significant.

Ninety two patients were included (28 women and 64 men). The mean sample age was 42 with a mean age of disease onset of 27. The mean duration of the treatment was 16 years in which the mean hospitalization rate of patients was six times. About the half of the patients suffered from paranoid schizophrenia. Women had a greater but not significant percentage of residual schizophrenia. A third of the sample had a history of violent behavior. Two thirds were cigarette consumers and 10.9% of them had other addictions. The mean BPRS score was 31.

The mean maintenance dose was 662.4±659.73mg eq CPZ. This is in the upper limit of the PORT recommendations. It is closely related to the Asiatic mean maintenance doses. More than one third of the sample had a maintenance dose superior to 600mg eq CPZ among which 43.75 % had doses superior to 1000mg eq CPZ. The variables which interfered significantly with the maintenance doses were polytherapy and the number and presentation (oral/depot) of psychotropic drugs. Polytherapy and an important number of psychotropic drugs where associated with high doses, whereas depot neuroleptics were associated with lower doses. No statistical relationships between the other variables cited in the literature and the maintenance doses were found.

The mean maintenance dose in schizophrenia seems to be influenced only by the pattern prescription.