Predicting antipsychotic-induced weight gain in first episode psychosis-a protocol for a field-wide systematic review of prognostic factor studies


  • Ita Fitzgerald Department of Pharmacy, St Patrick’s Mental Health Services, Dublin, Ireland School of Pharmacy, University College Cork, Ireland
  • Erin K. Crowley School of Pharmacy, University College Cork, Ireland
  • Amy Byrne Department of Pharmacy, Connolly Hospital, Blanchardstown, Dublin, Ireland
  • Jean O’Connell Endocrinology Department, St Columcille’s Hospital, Co. Dublin, Ireland. St Vincent’s University Hospital Group, Dublin, Ireland
  • Joie Ensor Centre for Prognosis Research, School of Medicine, Keele University, Staffordshire, United Kingdom
  • Ciara Ní Dhubhlaing Department of Pharmacy, St Patrick’s Mental Health Services, Dublin, Ireland College of Mental Health Pharmacy, United Kingdom
  • Sarah O'Dwyer Department of Medicine, St Patrick’s Mental Health Services, Dublin, Ireland
  • Laura J. Sahm School of Pharmacy, University College Cork, Ireland Department of Pharmacy, Mercy University Hospital, Cork, Ireland



Antipsychotic-induced weight gain, Metabolic side effects, Antipsychotics, Risk factors, Prediction, Psychosis


Background: One significant complexity associated with management of antipsychotic-induced weight gain (AIWG) is extensive interindividual variability amongst patients in initial susceptibility to AIWG, time to plateau of weight gain, and resultant final amount of weight gained. Prior to antipsychotic commencement, risk-stratified information highlighting those at increased risk of experiencing significant AIWG would allow tailored weight monitoring and subsequent management protocols to be developed.

Methods: This protocol is for a planned systematic review to identify the current utility of baseline clinical, sociodemographic, and biological prognostic factors in predicting the likelihood of significant AIWG occurring prior to antipsychotic commencement. The cohort assessed will be antipsychotic-naïve adults with a first episode of psychosis. Searches for both randomised and prospective non-randomised studies will be undertaken by searching four electronic databases and two trial registers, followed by reference searching, forward citation searching and liaison with content experts. A meta-analysis of study results will be undertaken where study quality and homogeneity allow. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework modified for prognostic research will be used to assess evidence certainty. This protocol was prepared in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) Protocols guideline and latest guidance from the Prognosis Methods Group of the Cochrane Collaboration.

Results: This review will establish the current quantity, quality and clinical utility of evidence addressing the prognostic association of clinical, biological, and sociodemographic factors in prospectively identifying those more likely to experience significant AIWG.

Registration details: PROSPERO registration number CRD42021258148.

Author Biography

Ita Fitzgerald, Department of Pharmacy, St Patrick’s Mental Health Services, Dublin, Ireland School of Pharmacy, University College Cork, Ireland

Senior Pharmacist, Pharmacy Department 

*Corresponding author - Ita Fitzgerald

Address - Pharmacy Department, St Patrick’s Mental Health Services, Dublin, Ireland.

Email –

Telephone – +353-1-2493262


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