Abnormal Regulation, Estimation and Cognitive Impacts of Physical Efforts as an Endophenotype of Anorexia Nervosa

Analysis of the Capacity to Regulate Physical Efforts and to Estimate Its Intensity as an Endophenotype of Anorexia Nervosa, Because of a Specific Impact of the Physical Effort at the Emotional, Cognitive, Pain, Genetic and Biological Level

The purpose of this study is to check if patients, but also relatives (as they share familial and genetic risk factors), are having more difficulties in regulating a spontaneous, pleasant physical effort (doing "too much") compared to healthy controls, and if physical efforts are participating to core symptoms of anorexia nervosa, such as more appetite (instead of less), less pain, more abnormal body image, and less cognitive flexibility.

Such a result could help to further understand the role of difficulties with physical exercise as part of the phenotype of anorexia nervosa.

This is a three steps protocol. First, patients (with anorexia nervosa), controls (with no eating disorder) and first degree relatives (with no eating disorder) will be tested for emotional accuracy (seing faces on a screen with different core emotions), pain threshold (how long they can support a cold probe), body size (how they see themselves), appetite and cognitive flexibility (a test where the capacity to change rules during a game is done easily or not).

Then all subjects will do a standardized physical exercise which represents an effort with the equivalent level of energy for each participants as being chosen according to each level of competency (assessed through the "maximal aerobic power").

The third step consists in the repetition of (nearly) initial tests.

Inclusion Criteria:

Patients :

• Woman
• 18 - 50 years
• eating disorders (with or without bulimia) according to the EDI-2 (Eating Disorder Inventory) and the MINI (Mini International Neuropsychiatric Interview)
• BMI (Body Mass index) between 14 and 17,5
• first degree relative without ED (eating disorders)

First degree relatives :

• Woman
• 18 - 50 years
• Mother or sister of patient with eating disorders
• BMI (Body Mass index) upper to 17,5
• Healthy of all ED (eating disorders)

Controls :

• Woman
• 18 - 50 years
• BMI > 17,5
• Without ED (eating disorders)

Exclusion Criteria:

All groups :

• Contraindication in the practice of an intensive sport
• Cardiovascular Family history with risk of cardiovascular unwanted events
• Cardiovascular, surgical personal Histories, ostéoarticulaires or musculo-tendinous against indicating to the practice of a sport
• Intercurrents psychiatric pathologies (humor or psychotics disorders, chronic or acute)

Related and controls :

Diagnosis of ED (eating disorders) in the EDI-2 and in the MINI