The impact of antipsychotic side-effects on attitudes toward medication in patients with schizophrenia and related disorders: a systematic review.

Background: Antipsychotics are associated with a wide range of side-effects. Many patients experience antipsychotics as unpleasant and something they would rather avoid, leading some of them to discontinue taking their medication. The importance of evaluating the patients' perspective, especially their attitudes toward medication in the presence of side-effects, has long been emphasized. However, no definite conclusion has been made to date on the relationship between antipsychotic side-effects and attitudes toward medication.
Objectives: The objective of this systematic review was to determine the best available evidence regarding the impact of antipsychotic side-effects on attitudes toward medication in patients with schizophrenia and related disorders, which include schizoaffective and schizophreniform disorders.
Inclusion Criteria: Types of studies - This review considered quantitative studies that examined the magnitude of the effect of antipsychotic side-effects on attitudes toward medication in patients with schizophrenia.Types of participants - This review considered studies that included adults aged 18 to 70 years old, with a confirmed diagnosis of schizophrenia or related disorders, and receiving antipsychotic treatment in any healthcare setting.Types of intervention - This review included studies that investigated the impact of antipsychotic side-effects using standardised scales.Types of outcomes - This review included studies that quantitatively measure attitudes toward medication using standardised scales. Attitudes toward medication refer to the patients' perception towards different aspects of medication including, but not limited to, medication-taking, medication effects, and/or medication side-effects.
Search Strategy: The search aimed to find published studies using a range of databases. A search strategy was developed using all identified keywords, and it was extended to the following databases: MEDLINE, CINAHL, PsycINFO, Scopus, ScienceDirect, and Web of Science. The search was limited to studies in English language and those published between the years 1990 to 2009.
Methodological Quality: Selected studies were assessed by two reviewers for methodological quality using the appropriate JBI critical appraisal instrument.
Data Collection: Data was extracted from the included studies using the appropriate JBI data extraction instrument.
Data Analysis: The heterogenous nature of the studies prevented statistical pooling of the data, thus the findings were presented in a narrative summary.
Results: A total of 13 studies were included in the review. Two studies found a positive relationship between attitudes toward medication and antipsychotic side-effects, while another five studies found a positive relationship between attitudes toward medication and specific side-effects such as sedation, concentration difficulties, increased sleep, diminished sexual desire, and extrapyramidal side-effects, specifically dyskinesia and parkinsonism. The remaining six studies found no positive relationship between attitudes and side-effects.
Conclusions: This review provides some support to the notion that patients experiencing antipsychotic side-effects are at risk of developing more negative attitudes toward medication. Implications for practice - Regular attitude assessments should be conducted for patients with side-effects, and prompt clinical interventions and patient education can be carried out to manage side-effects. Implications for research - There is a need for more quantitative studies to further understand the relationship between the two variables.