Nous présentons une revue de la littérature parue entre 1996 et 2004 concernant les indications psychiatriques et les effets indésirables de l’olanzapine chez l’enfant et l’adolescent. L’olanzapine s’avère efficace dans la schizophrénie infantile et de l’adolescent, dans les troubles bipolaires, dans l’anorexie mentale avec idéation délirante, dans les troubles envahissants du développement et dans les troubles du comportement sévères, associés ou non à des tics. L’effet indésirable le plus gênant est la prise de poids importante, suivi de la sédation, alors que les troubles extrapyramidaux restent légers à modérés. Les enzymes hépatiques, la glycémie, la prolactinémie peuvent être augmentées. Mais, quel que soit leur intérêt, la plupart de ces observations restent anecdotiques au regard de la méthodologie requise pour des essais cliniques valides, et la nécessité de disposer, en pédopsychiatrie, d’études menées selon les standards appliqués dans les autres disciplines, quelles qu’en soient les difficultés, est soulignée par tous.
Prescription of olanzapine in children and adolescent psychiatric patients
Introduction – A review of the literature from 1996-2004 on the indications and adverse reactions concerning the use of olanzapine, a second generation antipsychotic agent, in children and adolescents with psychiatric illness is made in this article. Studies lasted for 2 to 3 months and a few had a follow up period up to a year. Olanzapine, dosed from 2.5 to 20 mg/day, is shown to be a useful drug in the treatment of child and adolescent onset schizophrenia, bipolar disorder, anorexia nervosa with delusions, pervasive developmental disorder, tic disorders, and aggression. Open and double-blind studies – In 4 open labeled studies (26, 34, 39, 43) and 2 case reports (25), 53 patients, aged from 6-18 years old, afflicted by child onset schizophrenia, were treated with olanzapine for 1 1/2 weeks to one year ; 19 had treatment resistant childhood schizophrenia and 34 a first episode. In the first group 13/19 showed improvement whereas, in the second group 27/34 were considered responders. Four patients in the first group who had responded to clozapine (stopped because of adverse events) did less well on olanzapine. In 5 studies, 4 open labeled (15, 20, 44) and 1 double blind (27), 59 adolescent onset schizophrenic patients were treated by olanzapine from 8 to 26 weeks ; 50/59 patients were considered responders. In the open label study (20) comparing 43 adolescents treated by olanzapine (19 patients), risperidone (17 patients), or haloperidol (7 patients), improvement was significant in the three groups after 4 weeks of treatment and continued after 8 weeks. It is most interesting to mention that 2 months after the end of the study 71 % (12/17) of the olanzapine group that had completed the study, 10/15 (67 %) of the risperidone group, and 43 % (3/7) of the haloperidol group had continued their treatment. Dropouts were for inefficacy and non-compliance in the olanzapine and risperidone groups whereas they were also for adverse events in the haloperidol group (2/4). A final double blind study of 263 adult and adolescent schizophrenic patients (latter are not separated from the former) confirmed the superiority of olanzapine compared to haloperidol and its use for a long period : 67 % of the olanzapine and 54 % of the haloperidol patients completed the 12-week study. Case-reports – 12 case reports of children and adolescents diagnosed with acute mania (8, 25, 46, 47) and 23 in an open labeled study (16) were treated by olanzapine ; 26/35 were considered to respond well. Some of the patients were on mood stabilizers before adjunction of olanzapine, others on olanzapine monotherapy ; 10 case reports of patients with anorexia nervosa associated with psychotic symptomatology, aged from 10-17 years old, relate the use of olanzapine as adjuvant treatment. Improvement was spectacular in these patients who not only gained considerable weight, but were also more compliant to the therapeutic program and their obsessions, delusions, agitation and anxiety became less intense. In this form of anorexia nervosa, olanzapine appears to have an interesting therapeutic role and, in particular, its most important adverse effect, weight gain, became a therapeutic goal. In 2 preliminary studies (24, 30) 31 children and adolescents diagnosed with pervasive developmental disorder were treated by olanzapine from 6 to 13 weeks ; 18/25 had good or moderate symptomatic improvement : they were less irritable and hyperactive, and their speech less excessive. In 17 case reports of children and adolescents with aggression (42, 45), associated with tics in 10 patients (49), treatment with olanzapine from 2 weeks to 10 months lowered the presenting symptoms, enhanced the cooperation, and improved the mood of the patients. Only one patient’s treatment was changed for inefficacy. Discussion – No matter what the disorder treated, when olanzapine was compared to haloperidol and risperidone, it proved to be as effective as risperidone, and as or more effective than haloperidol ; but when compared to clozapine, it was less effective. The most prominent adverse reaction was excessive weight gain, even more so than in adult patients treated with olanzapine. Also weight gain was greater in children and adolescents treated by olanzapine than those treated by risperidone or haloperidol. Though few treatments had to be interrupted because of this side effect, child and adolescent psychiatrists are wary of the long-term disease related to obesity and glucose dysregulation. All should be done to understand the process of weight gain better and to prevent or stall excessive caloric intake, encourage activity, and eventually treat by corrector drugs. Secondly, sedation may bother up to 50 % of patients even at the end of the study periods, as many as those treated by haloperidol and more than those treated by risperidone. Extrapyramidal symptoms were mild or moderate compared to those that appear with haloperidol, but may be more frequent than in adult patients. Liver enzymes and blood sugar may be slightly elevated. Prolactemia may be elevated but less so with risperidone and haloperidol. Conclusion – All the authors emphasized the unfortunate lack of randomized double blind studies for the use of olanzapine in this age group.
Mots clés :
Troubles des conduites.
Keywords: Child and adolescent psychiatry , Conduct disorders , Olanzapine , Psychotic disorders.
* Pour le Groupe d’Étude Interdisciplinaire de Bretagne « Psychotropes chez l’enfant et l’adolescent », constitué de : Biologiste : C. Le Garzic (Centre Hospitalier Guillaume-Régnier, Rennes) ; Cardiologue : C. Lesquibe (Centre Hospitalier Guillaume-Régnier, Rennes) ; Neurologue et Pharmacologue : H. Allain (Service de Pharmacologie, Rennes) ; Pédopsychiatres : A. Belloir, C. Chevreuil, P. Dardenne, P. Guillemot, F. Leclere, C. Levenez, M. Renaud, T. Seveno, S. Tordjman, M. Wiss (Centre du Bois Perrin, Rennes), A. Lazartigues, E. Lemonnier (Psychiatrie Infanto-Juvénile, Bohars), T. Frémaux (CMPP du Gacet, Rennes) ; Pharmacologues : D. Bentué-Ferrer, J.-M. Reymann (Service de Pharmacologie, Rennes), E. Polard (Service de Pharmacovigilance, Rennes).
© 2007 Elsevier Masson SAS. Tous droits réservés.
Vol 33 - N° 2P. 188-196 - avril 2007 Retour au numéro
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