Identifying the profile of optimal candidates for antipsychotic depot therapy A cluster analysis

The prescription rate of antipsychotic depots for patients suffering from schizophrenia is currently low. Among these patients the assumable acceptance rate of depot as treatment of choice is markedly higher, but psychiatrists do report that patients frequently reject the offer of depot treatment. In a first step to highlight this contradiction we aimed at identifying attributes of patients that indicate their qualification for depot treatment in the eyes of the psychiatrists.

We surveyed 201 psychiatrists about their evaluation of patients' attributes potentially influencing their qualification for depot treatment. Multidimensional and cluster analyses were applied to detect associated attributes. A second sample of further 248 psychiatrists was asked about their proposal of depot treatment to patients depending on the number of relapses in the past.

Two clusters of attributes were identified characterizing patients' qualification for depot treatment. In cluster I episodes of non-compliance and relapses in the past were considered as favoring the qualification. cluster II included a high level of insight, openness to drug treatment and profound knowledge about the disease representing attributes that increase patients' qualification. Patients were significantly more likely to be offered depot treatment after their fourth reexacerbation compared to their first relapse.

Attributes comprised in cluster I highly qualify a patient for depot treatment which is in line with the current prescription stereotype. This conservative notion of depot use is supplemented by an alternative cluster II patient profile. Patients fitting this cluster also potentially qualify for depot treatment according to the surveyed psychiatrists and should be offered depot in clinical routine considering the advantages of this form of administration.