Prevalence of weight related comorbidities and eligibility for tirzepatide in an acute adult psychiatric inpatient population prescribed antipsychotics in Northern Ireland

Aims: The National Institute for Health and Care Excellence(NICE) has approved Tirzepatide, a glucagon-like peptide-1(GLP-1) receptor agonist, for obesity management in adults with Body Mass Index (BMI) ≥35 and one of the following weight related comorbidities: Type 2 Diabetes Mellitus; hypertension; dyslipidaemia; cardiovascular disease and/or obstructive sleep apnoea. Antipsychotic medications are known to be associated with weight gain and an elevated risk of cardiometabolic disorders. The aim of this audit was to determine prevalence of weight related morbidity and eligibility for Tirzepatide in an acute psychiatric inpatient population prescribed antipsychotics in Northern Ireland.

Methods: Inpatients in one acute adult psychiatric hospital prescribedat least one antipsychotic medication were audited. Demographics,antipsychotic use, BMI, and weight-related comorbidities wereextracted. Frequencies and proportions of weight-relatedcomorbidities and of patients eligible for Tirzepatide are presented.Group comparisons were made by sex and antipsychotic type.Statistical significance was performed using chi-squared tests.

Results: Seventy-five patients were audited, 41 females and 34 males.The mean age of the cohort was 46.1 years. Fourteen (18.7%) had aBMI ≥35 and thirty-one patients (41.3%) had at least one weightrelated comorbidity. Eleven patients (14.7%) met both criteria forTirzepatide eligibility.13 different antipsychotics were prescribed across the 75 patients.The most common antipsychotics used included Olanzapine (15),Aripiprazole (15), Quetiapine (11), Amisulpride (9), Risperidone (9)and Clozapine (9).Weight-related comorbidities were more prevalent in thoseprescribed Olanzapine (66.7%, 10/15) compared to other antipsychotics (35.0%, 21/60 (χ²=4.96, p<0.05)).Of the patients prescribed only a single second-generationantipsychotic 20.4% (10/49) met NICE criteria for Tirzepatidecompared to 0% (0/10) of patients prescribed a single first-generation antipsychotic (χ²=2.49, p=0.11) and 9.1% (1/11) onaripiprazole only (χ²=0.95, p=0.33).

Conclusion: Weight-related comorbidities were more prevalent inpatients prescribed Olanzapine compared to other antipsychotics.Up to 14% of this acute psychiatric inpatient population prescribedantipsychotics in Northern Ireland may be eligible for Tirzepatide formanagement of obesity.