Does Aberrant Decision Making Prevent Success in Adolescent Behavioral Weight Loss Treatment?

Adolescent overweight and obesity (AOB; i.e., a body mass index (BMI) greater than 85th percentile for age, height, and gender) affects 34.5% of adolescents. Over 80% of obese adolescents will become obese adults and experience increased risk of cardiovascular disease, type 2 diabetes, gallbladder disease, and some forms of cancer. Because of contraindications and hesitations to pursue psychopharmacology or bariatric surgery, behavioral interventions are the first-line treatment for AOB. Unfortunately, adolescent outcomes from pediatric behavioral obesity treatments are poor. In fact, the modal weight loss in behavioral interventions is less than a single BMI point, and many participants lose no weight at all. Outcomes in adolescents are worse than those found in younger children and adults. Notably, the vast majority of existing interventions tested in adolescents are designed for younger children, which may preclude an adolescent's success in these interventions. Successful behavioral AOB interventions may require augmentations that address developmental concerns unique to adolescence. For example, research has shown that, in contrast to younger children, many adolescents are making their own food decisions and are thus more likely to engage in problematic eating behaviors during treatment. As a necessary step towards developing specialized interventions for AOB, it is critical to understand the underlying mechanisms of continued engagement in problematic eating behaviors during AOB interventions.

Three types of problematic eating behaviors are strongly linked (cross-sectionally and longitudinally) with AOB. First, reward-driven overeating (i.e., frequently eating energy-dense foods) results in excess calorie intake, which, in turn, produces adiposity during childhood and adolescence. Second, loss-of-control eating (LOC; the experience of not being able to stop eating once started) is an exceptionally strong predictor of excess weight gain, i.e., an additional 2.4kg per year compared to peers without LOC. Third, rigid dietary restriction involves skipping meals and cutting out food groups for the purposes of weight regulation, but instead results in intense feelings of deprivation. As a result, rigid dietary restriction has the paradoxical effect of calorie overconsumption, excess weight gain, and poor outcomes from pediatric obesity treatment. Taken together, findings indicate that elucidating the drivers of these three problematic eating behaviors is critical to improving AOB treatment outcomes.

An aberrant decision-making framework represents an attractive paradigm for understanding the above-described problematic eating behaviors, especially given that they all run counter to adolescents' intentions and well-being. There are several aberrant decision-making processes endemic to the adolescent developmental period. Three of these processes in particular appear to be directly linked to the three problematic eating behaviors described above. To the extent that aberrant decision-making produces problematic eating behavior, aberrant decision-making can also be hypothesized to predict poor weight loss outcomes. Below, three aberrant decision-making processes and their links to problematic eating behavior are described.

Increased delay discounting. Delay discounting refers to the tendency to discount greater, later rewards in favor of smaller, sooner rewards. A combination of greater sensitivity to reward and slow development of self-regulatory neural processes contributes to especially high discounting rates in some adolescents. Relatively higher discounting rates may produce reward-driven eating, i.e., frequent consumption of energy-dense foods (e.g., high-fat, high sugar foods), while discounting the future reward (e.g., weight loss) that would be derived from forgoing immediate gratification. Indeed, a recent meta-analysis concluded that higher discounting rates were strongly cross-sectionally linked with AOB. Although behavioral weight loss programs discourage consumption of energy-dense foods, psychological strategies for how to prioritize long-term over short-term rewards are not provided. Thus, delay discounting likely contributes to continued reward-driven eating during treatment. However, no studies have tested whether delay discounting predicts reward-driven overeating (and its effect on weight) during AOB treatment.

Affect-driven impulsivity. Affect-driven impulsivity refers to a tendency to choose maladaptive behaviors geared towards the immediate cessation of a negative affective state, despite negative consequences. Affect-driven impulsivity likely drives continued LOC eating during treatment, precluding successful weight loss. Affect-driven impulsivity is a cross-sectional predictor of AOB, but it may be a particularly strong driver of LOC eating because compulsive eating serves the function of reducing distress. Although no studies have compared adolescents with and without LOC on affect-driven impulsivity, adolescents with LOC eating demonstrate overall higher levels of emotional reactivity and emotional eating. LOC eating resulting from affect-driven impulsivity may continue to occur during treatment because little treatment content focuses on skills for tolerating negative affect. Dr. Manasse's work demonstrates that increased affect-driven impulsivity predicts poor outcomes from adult binge eating treatment. However, no studies have examined whether affect-driven impulsivity predicts (1) engagement in LOC during treatment or (2) poor AOB treatment outcomes.