Given the clinical similarity and the frequent comorbidity between impulse control disorders and certain eating disorders (ED) such as bulimia nervosa, we aimed to compare personality and clinical profiles of individuals with and without substance use disorders (SUD) who had primary diagnoses of ED or impulse control disorders, namely pathological gambling (PG).

1096 ED [91.8% females] and 1120 PG [92.4% males] patients were assessed for the presence of SUD. All patients were consecutively admitted to our Psychiatry Department and diagnosed according to DSM-IV-TR criteria. We administered the Temperament and Character Inventory-Revised (TCI-R), the Symptom ChekList-90-Revised (SCL-90-R), and other clinical indices. Lifetime substance use included alcohol and other substances and was measured with the SCID-I. Student-Fisher t-tests were used to compare clinical features. Binary logistic regression models were used to analyse personality predictors of comorbidity with SUD. Adjustments for sex, age, and specific diagnosis were applied.

High Novelty Seeking, low Reward Dependence and low Self-Directedness were predictive of SUD in the whole sample independent of diagnosis (p<0.01). In the PG sample only, after adjustment for sex and age, Reward Dependence was no longer associated with SUD. Patients of both clinical samples with SUD showed higher SCL-90-R scores and severer eating and gambling symptoms (respectively).

Our results suggest that high Novelty Seeking, low Reward Dependence and low Self-Directedness are associated with lifetime SUD, which is also associated with a severer presentation of the primary disorder. This pattern holds across different populations such as ED and PG.