# What is Minimally Adequate Treatment of Psychosis and Should Duration of Inadequate Treatment be a Clinical and Research Target? A Perspective and State-of-the-Art Review

## TL;DR

This paper reviews how inadequate antipsychotic treatment in psychosis leads to worse outcomes and suggests defining a minimum treatment standard.

## Contribution

The paper proposes operational criteria for minimally adequate psychosis treatment and introduces duration of inadequate treatment as a potential research target.

## Key findings

- Inadequate antipsychotic treatment is linked to higher relapse risk, worse symptoms, and lower quality of life.
- Non-adherence rates in psychosis are as high as 56%, with limited evidence for disorders beyond schizophrenia.
- No standardized criteria exist for minimally adequate psychosis treatment, unlike for major depression.

## Abstract

Persistent symptoms and disability are common in psychotic disorders. This may be partly attributable to inadequate antipsychotic treatment, but there has not been a recent overview of what constitutes inadequate treatment and its impact on outcomes.

We focus on the latest meta-analyses to critically appraise the relationship between markers of inadequate antipsychotic treatment and outcomes from the first episode of psychosis onwards, relating outcomes to periods without antipsychotic use, antipsychotic treatment of subtherapeutic dose/duration, and antipsychotic partial/non-adherence.

Inadequate antipsychotic treatment is common (non-adherence rates = 44%-56%), and repeatedly associated with poorer outcomes across several key patient-centered outcomes, including increased risk of relapse (relative risk (RR) up to 2.70, n = 13 988), more severe overall symptoms (standardized mean difference (SMD) up to 0.78, n = 8878), poorer quality-of-life (SMD up to 0.50, n = 1421), poorer functioning (SMD up to 0.55, n = 1988) and higher mortality (RR up to 1.83, n = 272 030). We also find there is more evidence for schizophrenia than other psychotic disorders.

We identify that there are no operationalized criteria for the minimally adequate treatment of psychosis, in contrast to major depression, for example. We propose that a longer duration of inadequate treatment (DIT) may be an important predictor of outcome, although this has not been tested. To address this and support the development of interventions to reduce inadequate treatment, we propose operationalized criteria for the minimally adequate treatment of psychosis and the DIT, proposing both clinically applicable and research criteria. Finally, we consider future directions for research and practice.