Genetic Testing for Type 2 Diabetes

Diabetes Mellitus Clinical Trial

Official title:

The Impact of Genetic Testing for Type 2 Diabetes on Health Behaviors

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01060540
• Other study ID #: IBD 09-039
• Status: Completed
• Phase: N/A
• First received: January 29, 2010
• Last updated: April 6, 2015
• Start date: August 2010
• Est. completion date: March 2013

Study information

• Verified date: April 2014
• Source: VA Office of Research and Development
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Federal Government
• Study type: Interventional

Clinical Trial Summary

In this 6-month randomized, controlled trial, we examined whether providing participants with genetic test results and counseling regarding their risk for type 2 diabetes would motivate them to improve their health behaviors and lose weight to reduce their diabetes risk. We hypothesized that participants who received conventional diabetes counseling plus genetic test results and counseling would have at least 6 lb greater weight loss at 3 months than participants who received conventional diabetes counseling without genetic test results.

Description:

In this 6-month randomized, controlled trial, we evaluated the impact of genetic testing for type 2 diabetes on psychological, health behavior, and clinical outcomes. Eligibility criteria included age 21 to 65 years, overweight or obese (body mass index [BMI] >27 kg/m2), and no prior diagnosis of type 2 diabetes. At baseline, participants (N=601) had conventional risk factors assessed, including demographics, fasting plasma glucose (FPG), and family history. They also provided blood samples for genetic testing of TCF7L2, PPARG, and KCNJ11, three genes that confer elevated risk for development of type 2 diabetes. Participants were then randomized to receive conventional counseling plus control eye disease counseling (CR+EYE) or conventional counseling plus genetic test results (CR+G). Two to four weeks following the baseline visit, when the genetic test results were available, participants returned for a visit with a genetic counselor. All participants received conventional risk counseling based on their lifetime population risk, FPG results, and family history. Next, participants were informed of their randomization assignments; CR+EYE participants received counseling on eye diseases, whereas CR+G participants received genetic counseling. Then perceived risk, affect, self-efficacy, and readiness to change were assessed. All other outcomes were also assessed at 3 and 6 months.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 601
• Est. completion date: March 2013
• Est. primary completion date: March 2013
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 21 Years to 65 Years

Eligibility

Inclusion Criteria:

• body mass index >27 kg/m2

• baseline fasting plasma glucose <=125 mg/dL

Exclusion Criteria:

• prior diagnosis of type 2 diabetes

• fasting plasma glucose >125 mg/dL on more than one occasion

• HbA1c > 7%

• taking diabetes medication

• actively losing weight

• enrolled in research study focusing on lifestyle changes

• unable to provide informed consent or answer survey questions unassisted

• residing in nursing home or receiving home health care

• active diagnosis of psychosis or dementia

• at least one error on 6-item cognitive screener

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Diabetes Mellitus

Intervention

Genetic:
• genetic testing for type 2 diabetes
TCF7L2, PPARG, or KCNJ11

Behavioral:
• Conventional risk counseling
Risk based on lifetime risk, fasting plasma glucose results, and family history.
• eye disease counseling
addresses risk for age-related macular degeneration, glaucoma, cataracts

Locations

Country	Name	City	State
United States	Durham VA Medical Center, Durham, NC	Durham	North Carolina

Sponsors (2)

Lead Sponsor	Collaborator
VA Office of Research and Development	Duke University

Country where clinical trial is conducted

United States, 

References & Publications (2)

Voils CI, Coffman CJ, Edelman D, Maciejewski ML, Grubber JM, Sadeghpour A, Cho A, McKenzie J, Blanpain F, Scheuner M, Sandelowski M, Gallagher MP, Ginsburg GS, Yancy WS Jr. Examining the impact of genetic testing for type 2 diabetes on health behaviors: s — View Citation

Vorderstrasse AA, Cho A, Voils CI, Orlando LA, Ginsburg GS. Clinical utility of genetic risk testing in primary care: the example of Type 2 diabetes. Personalized medicine. 2013 Aug 1; 10(6):539-548.

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Weight	weight 3 months post-enrollment	3 months	No
Secondary	Insulin Resistance (HOMA2-IR)	Calculated using the updated homeostasis model assessment (HOMA) calculator at http://www.dtu.ox.ac.uk/homacalculator/; Higher numbers indicate higher insulin resistance. There are no established cutoffs indicating impaired resistance.	3 months	No
Secondary	Perceived Lifetime Risk of Type 2 Diabetes	measured on 1-7 scale (definitely will not get diabetes to definitely will get diabetes)	3 months	No
Secondary	Daily Caloric Intake	Estimated daily caloric intake based on self-reported frequency and amount of intake of specific foods over the past 3 months as assessed by the Block Brief Food Frequency Questionnaire	3 months	No
Secondary	Moderate Intensity Physical Activity	self-report based on the long version of the International Physical Activity Questionnaire. Moderate physical activity was queried in the domains of work (e.g., carrying light loads), transportation (e.g., bicycling), domestic chores and gardening (e.g., sweeping, raking), and leisure-time (e.g., bicycling, swimming).	3 months	No