Obesity rates in the United States have escalated in recent decades and present a growing challenge in public health prevention efforts. Advances in genomics have begun to shed light on the genetic contributions to obesity. At present, it is unknown whether information about one's personal genetic predisposition to obesity will add value to traditional risk communication efforts and increase the likelihood that individuals will engage in health behaviors to reduce obesity risk. The clinical utility and impact of this information on psychological, behavioral, and health outcomes have yet to be determined. Research is critically needed to identify the best practices for providing genetic information to individuals regarding their risk for obesity, which may serve as a model for understanding the behavioral responses to SNP testing for common diseases. The proposed study will examine the impact of providing genetic risk information for obesity on people's attitudes and beliefs about obesity, health behaviors and weight outcomes. We will conduct a randomized controlled feasibility trial to examine the short-term impact of risk feedback for obesity, using a 2x2 factorial design. The two factors will be genetic risk feedback (no/yes) and lifestyle risk feedback (no/yes), resulting in four conditions: 1) neither genetic or lifestyle risk feedback (wait-list control), 2) genetic risk feedback only, 3) lifestyle risk feedback only, and 4) both genetic and lifestyle risk feedback combined.
The specific aims of the study are to: 1) examine the effects of providing innovative genetic risk feedback, alone or in combination with lifestyle risk feedback, on participants'behavioral intentions, health behaviors (physical activity, diet, television viewing), and weight outcomes, and 2) determine the extent to which the effects of genetic and/or lifestyle risk feedback vary as a function of risk status (elevated versus non-elevated). We will also examine the mechanisms by which genetic and/or lifestyle risk information may influence lifestyle behaviors, guided by self-regulation theory. This study will be the first to obtain pilot data on the short-term (mechanism-focused) impact of providing obesity genotype feedback on actual behavioral outcomes among both overweight and non-overweight individuals. Because this is a pilot study, data will be used to develop effect sizes and variance estimates to be used in planning a larger randomized trial. We will determine the "value added" of genetic information when combined with lifestyle risk feedback, and whether it enhances motivation to engage in healthy lifestyle behaviors. Moreover, we will also determine whether providing "low risk" genetic feedback has any adverse effects (e.g., false reassurance). Finally, this study is uniquely situated to provide important data on how individuals interpret different sources of risk information and how they arrive at an overall perception of risk for a condition. Taken altogether, study findings will be used to serve as an overall model for future intervention efforts to effectively communicate genetic risk information with the goal of improving weight management and overall population health. 1
Although genetic testing for obesity is widely available to the public through direct-to-consumer companies, little is known about the impact of this information on people's attitudes towards obesity, health behaviors, and weight outcomes. This study will examine the feasibility of using obesity-related genetic information to motivate individuals to reduce their risk for obesity. Study findings will serve as an overall model for future intervention efforts to effectively communicate genetic risk information with the goal of improving weight management and overall population health.
|Wang, Catharine; Gordon, Erynn S; Stack, Catharine B et al. (2014) A randomized trial of the clinical utility of genetic testing for obesity: design and implementation considerations. Clin Trials 11:102-13|