[Assessing various aspects of the motivation to eat that can affect food intake and body weight control]

Over the last 30 years, several questionnaires have been developed and validated in order to assess many aspects of the motivation to eat that might be susceptible to impair adequate food intake and body weight control. A few of such questionnaires are described here, in particular, the "Three Factor Eating Questionnaire" also called the "Eating Inventory", and the "Dutch Eating Behavior Questionnaire". Critical aspects of the motivation to eat assessed by these tools are presented, such as dietary restraint, disinhibition, hunger, vulnerability to eat in response to external cues or emotional states, etc. These questionnaires were developed for use in the general population with the aim to identify critical aspects of the motivation to eat that might predispose to weight gain. They have been widely used in many countries and have allowed an improved understanding of the individual characteristics that predispose to body weight gain or resistance to weight loss. Originally, poor body weight control was attributed to a high level of dietary "restraint", or in other words, the tendency to deliberately restrict one's food intake for body weight control purposes. Such dietary restraint was suspected to lead to a number of physical and psychological difficulties, among which poor self-esteem and a paradoxical tendency to gain weight, resulting from the incapacity to maintain strict restraint over time. More recent studies have established that a motivational trait called "Disinhibition" is a strong predictor of body weight gain over time and of poor outcome of dieting. "Disinhibition" corresponds to a tendency to lose control over one's eating behavior and ingest excessively large quantities of food substances, in response to a variety of cues and circumstances. In addition to its untoward effect on weight, disinhibition also predicts various risk factors and pathologies, such as hypertension and diabetes. Other potentially critical dimensions for adequate body weight control are "emotional eating" and "externality", which represent an individual's vulnerability to eat in response to emotional states or external cues, respectively. These questionnaires have been translated into French and validated for the French population. Average data are available for normal weight and obese French men and women. A gender difference is often reported: women, and even young girls, tend to have higher scores than males for most dimensions. These questionnaires have been extensively used in populations without psychiatric disorders, with the only exception of diagnosed eating disorders such as anorexia and bulimia nervosa. The questionnaires have not been used until now in populations with other types of psychiatric disorders, such as schizophrenia or bipolar disease. Their relevance for such populations is now an important question, since last generation pharmaceutical treatments of such psychiatric disorders seem to adversely affect body weight control. It then becomes critical to know whether the psychological dimensions assessed by such questionnaires reflect the action of pharmacological agents that induce weight gain. A research project is now in progress at Sainte-Anne Hospital to investigate many dimensions of the motivation to eat, as assessed by the questionnaires, in psychiatric patients receiving various types of antipsychotic agents. The results of this original study might provide hints about the mechanisms that lead to body weight gain in patients receiving certain types of antipsychotic pharmacological agents and potentially help in preventing or reversing the weight gain associated with such treatments.