OBJECTIVETo examine whether diabetes genetic risk testing and counseling can improve diabetes prevention behaviors.RESEARCH DESIGN AND METHODSWe conducted a randomized trial of diabetes genetic risk counseling among overweight patients at increased phenotypic risk for type 2 diabetes. Participants were randomly allocated to genetic testing versus no testing. Genetic risk was calculated by summing 36 single nucleotide polymorphisms associated with type 2 diabetes. Participants in the top and bottom score quartiles received individual genetic counseling before being enrolled with untested control participants in a 12-week, validated, diabetes prevention program. Middle-risk quartile participants were not studied further. We examined the effect of this genetic counseling intervention on patient self-reported attitudes, program attendance, and weight loss, separately comparing higher-risk and lower-risk result recipients with control participants.RESULTSThe 108 participants enrolled in the diabetes prevention program included 42 participants at higher diabetes genetic risk, 32 at lower diabetes genetic risk, and 34 untested control subjects. Mean age was 57.9 ± 10.6 years, 61% were men, and average BMI was 34.8 kg/m2, with no differences among randomization groups. Participants attended 6.8 ± 4.3 group sessions and lost 8.5 ± 10.1 pounds, with 33 of 108 (30.6%) losing ≥5% body weight. There were few statistically significant differences in self-reported motivation, program attendance, or mean weight loss when higher-risk recipients and lower-risk recipients were compared with control subjects (P > 0.05 for all but one comparison).CONCLUSIONSDiabetes genetic risk counseling with currently available variants does not significantly alter self-reported motivation or prevention program adherence for overweight individuals at risk for diabetes.

OBJECTIVERapid advances in diabetes genetic epidemiology may lead to a new era of “personalized medicine” based on individual genetic risk assessment. There is minimal experience to guide how best to clinically implement such testing so that results (e.g., “higher” or “lower” relative genetic risk) improve rather than reduce patient motivation for behavior change.RESEARCH DESIGN AND METHODSBetween November 2009 and May 2010, we conducted in-depth interviews with 22 overweight participants at high phenotypic risk for type 2 diabetes to explore perceptions of diabetes genetic risk testing compared with currently available prediction using nongenetic risk factors (e.g., family history, abnormal fasting glucose, obesity). We used hypothetical scenarios to specifically investigate the impact of both “higher” and “lower” relative genetic risk results on participants’ views about diabetes prevention.RESULTSMany participants conferred a unique value on personal genetic risk information relative to nongenetic risk based on the perceived scientific certainty and durability of genetic results. In contrast, other participants considered their genetic risk within the overall context of their other measured risk factors. Reactions to diabetes genetic test results differed by current motivation levels. Whereas most subjects reported that “higher” risk results would motivate behavior change, subjects with lower current motivation often reported that “lower” genetic risk results would further reduce their motivation to engage in diabetes prevention behaviors.CONCLUSIONSTo be effective, future clinical implementation of type 2 diabetes genetic risk testing should be individualized based on each patient’s risk perception and current level of motivation to prevent diabetes.

Advances in genetic epidemiology have increased understanding of common, polygenic preventable diseases such as type 2 diabetes. As genetic risk testing based on this knowledge moves into clinical practice, we propose that genetic counselors will need to expand their roles and adapt traditional counseling techniques for this new patient set. In this paper, we present a genetic counseling intervention developed for a clinical trial [Genetic Counseling/Lifestyle Change for Diabetes Prevention, ClinicalTrials.gov identifier: NCT01034319] designed to motivate behavioral changes for diabetes prevention. Seventy-two phenotypically high-risk participants received counseling that included their diabetes genetic risk score, general education about diabetes risk factors, and encouragement to participate in a diabetes prevention program. Using two validated genetic counseling scales, participants reported favorable perceived control and satisfaction with the counseling session. Our intervention represents one model for applying traditional genetic counseling principles to risk testing for polygenetic, preventable diseases, such as type 2 diabetes.

Background Type 2 diabetes genetic risk testing might motivate at-risk patients to adopt diabetes prevention behaviors. However, the influence of literacy and numeracy on patient response to diabetes genetic risk is unknown. Objective The authors investigated the association of health literacy, genetic literacy, and health numeracy with patient responses to diabetes genetic risk. Design and Measurements Overweight patients at high phenotypic risk for type 2 diabetes were recruited for a clinical trial of diabetes genetic risk testing. At baseline, participants predicted how their motivation for lifestyle modification to prevent diabetes might change in response to hypothetical scenarios of receiving “high” and “low” genetic risk results. Responses were analyzed according to participants’ health literacy, genetic literacy, and health numeracy. Results Two-thirds (67%) of participants (n = 175) reported very high motivation to prevent diabetes. Despite high health literacy (92% at high school level), many participants had limited health numeracy (30%) and genetic literacy (38%). Almost all (98%) reported that high-risk genetic results would increase their motivation for lifestyle modification. In contrast, response to low-risk genetic results varied. Higher levels of health literacy (P = 0.04), genetic literacy (P = 0.02), and health numeracy (P = 0.02) were associated with an anticipated decrease in motivation for lifestyle modification in response to low-risk results. Conclusions While patients reported that high-risk genetic results would motivate them to adopt healthy lifestyle changes, response to low-risk results varied by patient numeracy and literacy. However, anticipated responses may not correlate with true behavior change. If future research justifies the clinical use of genetic testing to motivate behavior change, it may be important to assess how patient characteristics modify that motivational effect.