No evidence for cross-sectional or longitudinal associations between cognitive flexibility performances and nutritional status in a cohort of inpatients with anorexia nervosa.

Objective: According to the Cognitive-Interpersonal model of Anorexia Nervosa (AN), the combined influence of cognitive and socio-emotional difficulties would constitute vulnerability and maintaining factors. Poor cognitive flexibility is one of the endophenotypic candidates of the disorder but few studies examined its association with weight status. The study aimed to evaluate the relationships between cognitive flexibility performances and nutritional status indices (BMI; Body composition: fat mass: FM ; fat-free mass: FFM) at different stages of the disorder. Methods: Cross-sectional and longitudinal associations between cognitive flexibility (TAP 2.1 subtest) and BMI, FM and FFM, anxious and depressive (HAD), and eating disorder (EDE-Q) symptomatology were investigated using univariate and multivariate analyses in a cohort of AN inpatients evaluated at hospital admission (N=167) and discharge (N=94). Results: We found no or negligible associations between nutritional status markers, HAD or EDE-Q scores and cognitive flexibility performances either cross-sectionally or longitudinally. Performances did not significantly differ between the restrictive and binge-purging subtypes. Conclusion: In agreement with the Cognitive-Interpersonal model of AN, cognitive flexibility is independent of nutritional status as well as the AN subtype. It is also independent of the levels of anxious, depressive, or ED symptoms. A new therapeutic approach targeting cognitive flexibility and intolerance to change could benefit severely emaciated people with AN, regardless of disease’s subtype and level of dysphoria.