ABSTRACT
<p><b>INTRODUCTION</b>Anorexia nervosa (AN) and eating disorders not otherwise specified (EDNOS) are on the rise in Singapore. Abnormal liver function tests have been reported for up to 12.2% of patients with AN. These patients are also known to present with comorbid psychiatric disorders. This study aims to investigate the correlation between body mass index (BMI) and the severity of abnormal liver function tests, and between BMI and the presence of comorbid psychiatric disorders.</p><p><b>METHODS</b>A retrospective cohort analysis of 373 patients diagnosed with AN or EDNOS at a tertiary hospital was performed. The clinical course of transaminitis and comorbid psychiatric disorders was correlated with the patient's BMI.</p><p><b>RESULTS</b>Patients with a BMI of ≥ 16.6 kg/m(2) at their first consult had a significantly lower risk of having comorbid psychiatric disorders (χ(2) = 32.08, p < 0.001). These patients were five times less likely to have comorbid psychiatric disorders as compared to patients from the other BMI groups (odds ratio [OR] 0.21). On the other hand, patients with a BMI of < 14.6 kg/m(2) had a significantly higher risk of having transaminitis (χ(2) = 72.5, p < 0.001). They were 11.1 times more likely to develop transaminitis as compared to patients with a BMI of ≥ 14.6 kg/m(2) (OR 11.05).</p><p><b>CONCLUSION</b>Severity of BMI can be used by clinicians as an indicator to assess for secondary psychiatric comorbidities and/or transaminitis during the first consultation. This could help reduce the morbidity and mortality rates in patients with AN or EDNOS.</p>