The association of metabolic syndrome and long acting injectable antipsychotics: A systematic review

Background and Objectives

Long-acting injectable (LAI) antipsychotics increase patient adherence, reduce relapse rates and facilitate regular interaction with community mental health teams. Antipsychotics are however associated with adverse effects including metabolic syndrome. This review outlines the rates of monitoring for and rates of metabolic syndrome in patients treated with LAI antipsychotics.

Methods

We searched Medline, EMBASE, and Cochrane for Medical Subject Heading (MeSH) terms including metabolic syndrome or MetS and depot or LAI antipsychotics. We included data regarding participants’ clinical characteristics, dose and type of antipsychotics administered, rates of monitoring for- and rates of metabolic syndrome and individual metabolic parameters (body mass index or measure of central obesity, blood pressure, lipid levels, plasma glucose and/or HbA1C levels).

Results

Six studies were included that evaluated rates of monitoring for- and 39 studies examined rates of metabolic syndrome or individual metabolic parameters. Metabolic parameters were not routinely measured in approximately 75% of patients. Rates of metabolic syndrome ranged between 24.3% and 53.2%, with most studies finding no significant differences between oral and LAIs; however, a more preferable weight and lipid profile was detected with LAIs compared to the oral antipsychotics olanzapine and clozapine. Rates of metabolic syndrome and abnormalities of metabolic parameters were comparable among first- and second-generation and between second-generation LAIs.

Conclusions

LAI antipsychotics are associated with high rates of metabolic syndrome but low rates of regular monitoring. A robust screening plan to monitor for metabolic syndrome in individuals treated with LAIs is advised including measurement of individual metabolic parameters.