Walburn et al (Reference Walburn, Gray and Gournay2001) are correct to place their conclusions regarding patients' favourable attitude to depot antipsychotic medication in the context of the paucity of studies using unselected patient samples. Indeed, depot preparations tend often to be used for patients who are otherwise unlikely and/or unwilling to accept antipsychotic medication, and a true reflection of patient attitudes to depot antipsychotics can be established only from research based on representative samples of patients with psychotic illnesses.
In Australia, the study of Low Prevalence (Psychotic) Disorders (Reference Jablensky, McGrath and HerrmanJablensky et al, 2000), conducted in 1997-1998, allowed an arguably more accurate evaluation of patients' attitudes to depot medication. In this study, 998 persons with a non-organic psychosis were randomly selected from all patients in contact with services during an index month, as well as selected groups who were not in contact with services in the index month, but had been in the previous 3 years. Also included was a group ascertained through ‘marginal’ services, such as homeless shelters.
The study established diagnoses, symptoms, disability and service utilisation for each participant. In terms of medication, around half were on ‘typical’ antipsychotics, with half of these being administered in depot form. A further 8.3% were on clozapine, 13.3% on risperidone and 8.8% on olanzapine. Demographic and illness parameters did not distinguish medication groups, although usage varied across different service providers. Clozapine tended to be used in patients with a long illness duration, compared with other agents.
Patients reported a mean of around 3.5 of a possible 14 medication side-effects. Some 83% of those using depot medication reported side-effects, compared with 79% of those using typical oral medication. Patients on depot preparations of typical antipsychotics reported the highest rates of akathisia, and were also least likely to perceive their medication as helpful; indeed, 17% rated it as ‘not helpful’ v. 12% of those on oral typical antipsychotics, 10% of those on olanzapine/risperidone and 5% of those on clozapine.
Thus, in unselected patient populations, patient perception of depot medications appears less favourable than the studies reviewed by Walburnet al might lead us to believe. Clinicians should attempt to enhance adherence to antipsychotics by means other than necessarily resorting to depot medication.
EDITED BY MATTHEW HOTOPF