Similar subjective response and adherence rates for long-acting risperidone and conventional depots

Background and Aims:Amongst oral antipsychotics, tolerance and adherence are thought to be higher with atypicals versus conventional agents. Fewer data exist for parenteral antipsychotics regarding the atypical–conventional comparison.Aim:to compare adherence rates and subjective response between long-acting risperidone (LAR) and conventional depots.Methods:Cross-sectional, naturalistic, one-site study of all outpatients with severe mental disorders treated with injectable antipsychotics over a 12–month period at one Spanish mental health unit. Different sets of broadly– and narrowly–defined criteria for adherence were calculated from mental health nurse´s registry data. Patients´ subjective response was self-assessed with the Subjective Well-being under Neuroleptic treatment (SWN) and the Drug Attitude Inventory (DAI-10).Results:Subjects treated with LAR (n=27) and conventional depots (n=22) were similar in clinical and demographic terms. Both groups reported mostly positive subjective responses with the SWN (LAR=71.8+18.4 vs depots=81.7+15.3) and the DAI-10 (LAR=3.0+4.8 vs depots=4.0+4.5), with non-significant differences. Regardless the criteria of adherence used, rates of non-adherent subjects were also comparable, ranging from 36% (narrowly–defined) to 82% (broadly–defined). Although mean telephone prompts were higher for the LAR group (p=0.002), this difference disappeared when interval of administration (14 vs 28 days) was taken into account (ANCOVA: F=0.76; p=0.4).Conclusions:In this small study, atipicity would not influence attitudes or subjective response to parenteral antipsychotics. Furthermore, the two–fold administration frequency of long-acting risperidone compared to depots does not seem to lead to higher rates of non–compliance amongst outpatients with severe mental disorders.