Long-acting injectable or oral antipsychotic for first episode psychosis?

Antipsychotic therapy improves outcomes for patients with first episode of psychosis, yet a study presented at IEPA11 by Sally Mustafa from McGill University, Montreal, Canada showed a 72% rate of discontinuation of the first oral antipsychotic.

Predictors of discontinuation of initial oral antipsychotic in first-episode psychosis

The rate of and time to discontinuation of an initial antipsychotic over a 1-year period prescribed to 390 patients with first-episode psychosis and the factors influencing such discontinuation have been evaluated by Dr Mustafa and her colleagues. The effects of a number of putative predictors of discontinuation were estimated using regression analyses.

Discontinuation of the initial antipsychotic is common when treating first-episode psychosis

The rate of discontinuation of the first antipsychotic was 72%, with no difference between three investigated antipsychotics, and the mean time to discontinuation was 7.2 months and did not differ for the three antipsychotics.

Binary logistic regression showed lower rates of discontinuation were associated with:

  • higher positive and negative symptoms
  • remission
  • baseline functioning

Multiple linear regression showed the same predictors were also associated with a longer time to discontinuation in addition to male gender and less weight gain per month of exposure to the initial antipsychotic.

Major factors associated with continuing an antipsychotic medication appear to be:

  • symptom relief
  • better functioning
  • less side effects

Who benefits from early prescription of LAI?

Early relapse is frequent in FEP, mainly because of poor adherence to medication. A 3-year, longitudinal, prospective, study of all patients admitted with psychosis for early intervention services was conducted to evaluate the impact of early LAI administration on relapse and re-hospitalization rates for FEP.

LAI appears to benefit patients with poor prognosis and younger patients with early disease

Among 416 patients, who were subdivided into four groups according to the route of antipsychotic administration, those who received an LAI at first were more likely to be affected by poor prognostic factors — lower pre-morbid functioning, homelessness, substance use disorder and schizophrenia spectrum diagnoses. However, their relapse rate over time was similar to those with good prognostic factors who received only oral antipsychotics.

Patients who were initially prescribed oral antipsychotics and who eventually switched to LAI were more likely to relapse and to be re-hospitalized in a larger proportion and more rapidly than those started on LAI, even if they had better functioning at baseline. However, they were younger and more likely to have substance use disorder.

Patients with poor prognosis and younger patients in the early stage of their disease therefore seem to benefit from early prescription of LAI.