Behavioral Consequences of Testing for Obesity Risk

Abstract

Objective: There is considerable hope that genetic susceptibility testing will motivate behavior that can prevent or reduce the risk of complex conditions such as obesity. This study examined potential behavioral consequences of such testing. Methods: Participants (n = 249) were randomly assigned to review one of four vignettes that asked them to imagine that they had been tested for their risk of becoming overweight or obese. The experimental factors were test type (genetic versus hormone test) and risk level (increased versus average risk for obesity). Study measures included behavioral intentions and perceived behavioral control related to eating a healthy diet, as well as weight locus of control. Results: Participants assigned to the increased risk conditions indicated greater intentions to eat a healthy diet compared with participants assigned to the average risk conditions (P < 0.02). There were significant interaction effects of risk  perceived behavioral control (P < 0.02) and risk  weight locus of control (P < 0.003) on dietary intentions. Individuals with low perceived behavioral control or an external weight locus of control who were told to imagine they were at average risk expressed significantly lower intentions to eat a healthy diet. A three-way interaction of body mass index, family history of overweight/ obesity, and assigned risk level found the greatest effects of risk feedback among those who either had a family history or a higher body mass index (P < 0.007). Conclusion: This study provides preliminary evidence that testing for susceptibility to obesity may motivate healthier behavior. However, some individuals may be susceptible to a false reassurance effect after receiving test results indicating a lack of increased risk. (Cancer Epidemiol Biomarkers Prev 2005;14(6):1485 -9)

Can genetic risk information for age-related macular degeneration influence motivation to stop smoking? A pilot study

“…22,23,31 Sanderson and Michie 21 found knowledge of high genetic risk of developing heart disease had a positive influence on intention to quit smoking. A study of genetic risk information for coronary heart disease by Wright et al 23 found the gene positive group had greater intentions to quit compared with the no test group.…”

“…We utilized a common vignette paradigm that asks individuals to consider different hypothetical scenarios for genetic testing. [21][22][23] …”

Patient compliance based on genetic medicine: a literature review

“…When comparing genetic test results to other (nongenetic) biomarker results, those who were informed about an increased risk of becoming obese were found to have demonstrated higher intention to eat a healthy diet (Frosch et al 2005). The test type (genetic or hormone test) had no effect on the perceived risk or intention to eat a healthy diet.…”

“…The authors concluded that a positive obesity gene status would not adversely affect people's confidence in their ability to lose weight or control their eating behavior in difficult situations. Frosch et al (2005) published an analog study where 249 undergraduate students (BMI between 18.5 and 29.9) were asked about their attitudes, perceived behavior control and outcome expectancies towards eating a healthy diet after receiving a test result about a higher risk of becoming obese. Hypothetical test results were based either on a "genetic test" or on a "hormonal test" revealing increased or average risk of becoming obese.…”

Rapid aneuploidy detection or karyotyping? Ethical reflection

“…82 There is also a risk that the group found to have a lower than average risk might unjustifiably feel that they are protected, and so be less motivated towards healthy behaviour. 56,83,84 So not everything that might result from new screening opportunities in this area is necessarily beneficial. However, the concept of individualised preventive medicine captures the imagination and is easy to sell.…”