Introduction: In this study, we present seven case reports concerning patients suffering from schizophrenia or schizo-affective disorders, treated by aripiprazole.
Study design: Through these patient case reports, we have attempted to highlight the specificities of aripiprazole's action on schizophrenic symptoms, especially in the cognitive dimension. In acting as a regulator more than as a brake on the translation messages between neurons, aripiprazole does not increase cognitive disorders, but may have a procognitive affect.
Results: We particularly noticed an improvement in attention abilities, both in selective attention - in order to take into account the context of the situation - and in sustained attention allowing patients to maintain a stable and appropriate level of efficiency while performing an activity. Case reports (n 2, n 3 and n 5) also seem to show the ability of aripiprazole to improve working memory: indeed, abilities of patients to maintain and recall information regarding different cognitive activities required in rehabilitation psychiatric care were noticed with aripiprazole while they were not with previous antipsychotic drugs used in the same patients.
Discussion: Our sample, although too small for global consideration, suggests that aripiprazole provides stimulating properties for schizophrenic patients including those with primary deficient syndrome. This action, probably through cognitive improvement, needs some clarification in more precisely defining deficit features as juxtaposed by the classical criteria used on the SANS-SAPS and PANSS scales. Finally, we should stress aripiprazole's rapidity of effect. In half the cases, the reported improvement in our patients occurred during the first week of treatment. Hence, the patient should be informed of the short time-span effect for aripiprazole, in order to prevent the emergence of symptoms due to the rapid switch of medication and eventual side effects.
Conclusion: Aripiprazole acts as a partial agonist of D2 receptors as well as a partial agonist of 5HT1A and an antagonist of 5HT2A. This drug constitutes the first that permits regulation of both the dopamine and serotonine systems: dopamine activity is blocked when D2 receptors are over-stimulated and increased when D2 receptors require stimulation; on the other hand, in the cortical region, the inactivation of 5HT2A allows for a release of dopamine firing, whereas in the striatum where the 5HT2A receptors density is increased, their blockage inhibits dopamine release and limits extrapyramidal symptoms. In addition, the synergy between 5HT1A antagonism and 5HT2A antagonism seems to provide aripiprazole with both anxiolytic and affective properties. Finally, the absence of an affinity for histamine, muscarinic and adrenergic alpha-1 receptors limits the side effects compared to other antipsychotic drugs.