Treatment Adherence in Schizophrenia: Which Antipsychotic Is Best?

Treatment patterns varied between the SGA-LAI and OAP groups as well.1 The study authors found that the number of prescription fills for the index drug in the follow-up period was significantly higher in SGA-LAI patients compared to OAP patients (9.1 vs 8.3 claims, respectively; P<0.001). A reduction in the use of AP and adjunctive therapy was also seen in patients receiving SGA-LAI compared to those receiving OAP. Of the OAP patients, 67.5% reported the use of AP medications compared to 63.1% of patients receiving SGA-LAI (P<0.001). Additionally, 68.8% of SGA-LAI patients reported using adjunctive therapy compared to 89.8% of OAP patients (P<0.001). The presence of psychiatric polypharmacy was also found to be lower in the SGA-LAI group compared to the OAP group (46.8% vs 70.2%, respectively; P<0.001).

Adherence and persistence results obtained during the study are summarized in Table 2.1 The study authors reported that, compared to patients receiving OAP, adherence was higher in the SGA-LAI group but lower in the FGA-LAI group. Additionally, the proportion of days covered (PDC) for the index medication was found to be higher in SGA-LAI patients compared to OAP patients. Although analysis found that persistence was always significantly higher in the SGA-LAI group compared to the OAP group, no definitive pattern in persistence was observed in patients receiving FGA-LAI.

The study authors also reported adjusted adherence and persistence results for all treatment groups due to the “differences in baseline characteristics observed between cohorts.”1 The adjusted comparisons are shown in Table 3. According to the adjusted results, SGA-LAI patients were consistently more adherent and persistent with their medication compared to OAP patients. Additionally, of the results that were statistically significant, patients receiving FGA-LAI were less adherent and persistent with their medication versus those receiving OAP.

The study authors noted several limitations to their study, which are listed in Table 4.1 Despite these limitations, it was concluded that “patients initiated on SGA-LAI were more likely to be adherent and persistent to their medication than patients initiated on OAP, while such difference was not as clear for patients initiated on FGA-LAI.”

Additionally, it was found that, compared to OAP, SGA-LAI therapy was associated with a reduction in the use of other AP therapy and AP polypharmacy while FGA-LAI therapy led to an increase in AP polypharmacy. Finally, the authors noted that “further studies are warranted to understand the impact of these AP treatments on clinical and economic outcomes.”