Evidence that hedonic response toward sugar in alcohol use disorder is mediated by antidepressant use and does not constitute an endophenotype.

Background: Literature highlighted a higher sweet preference among patients with alcohol use disorder (AUD) that may act as an endophenotypical vulnerability. However, results remain heterogenous and seldom information is available regarding possible origins, such as hedonic abilities, reward sensitivity or impulsivity.

Objective: This cross-sectional study aims to explore the relationship between AUD and sweet preference as well as its endophenotypical properties.

Methods: Ninety-two participants were divided into three groups (36 patients with AUD, 29 healthy controls and 27 healthy first-degree relatives), and were asked to take a sweet preference test, a hedonic test, the Iowa Gambling Task (IGT) and self-reported inventories measuring impulsivity (Barratt Impulsiveness Scale [BIS-11]), anxiety and depression (Hospital Anxiety and Depression scale [HADS]). A stepwise linear regression with all available variables was performed to compare patients and controls. Factors included in the retained model were then added as mediators in a path analysis.

Results: Compared to healthy controls, patients with AUD had a lower sweet score. The difference lost its significance in the linear regression: the retained model only included antidepressant use (p = .016) and tobacco use status (p = 0.074). The path analysis showed that antidepressant use, but not tobacco use status, significantly mediated the effect of AUD on sweet preference. Sweet score did not significantly differ between first-degree relatives and the two other groups.

Conclusions: Our results do not support the hypothesis that sweet preference is an endophenotype of AUD. Instead, they suggest that the association between sweet preference and AUD may be mediated by confounding factors such as antidepressant use.