Genetic Testing for Type 2 Diabetes

This study has been completed.
Sponsor:
Collaborator:
Duke University
Information provided by (Responsible Party):
Department of Veterans Affairs
ClinicalTrials.gov Identifier:
NCT01060540
First received: January 29, 2010
Last updated: July 11, 2014
Last verified: July 2014
  Purpose

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.


Condition Intervention
Diabetes Mellitus
Genetic: genetic testing for type 2 diabetes
Behavioral: Conventional risk counseling
Behavioral: eye disease counseling

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Prevention
Official Title: The Impact of Genetic Testing for Type 2 Diabetes on Health Behaviors

Resource links provided by NLM:


Further study details as provided by Department of Veterans Affairs:

Primary Outcome Measures:
  • Weight [ Time Frame: 3 months ] [ Designated as safety issue: No ]
    weight 3 months post-enrollment


Secondary Outcome Measures:
  • Insulin Resistance (HOMA2-IR) [ Time Frame: 3 months ] [ Designated as safety issue: No ]

    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.


  • Perceived Lifetime Risk of Type 2 Diabetes [ Time Frame: 3 months ] [ Designated as safety issue: No ]
    measured on 1-7 scale (definitely will not get diabetes to definitely will get diabetes)

  • Daily Caloric Intake [ Time Frame: 3 months ] [ Designated as safety issue: No ]
    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

  • Moderate Intensity Physical Activity [ Time Frame: 3 months ] [ Designated as safety issue: No ]
    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).


Enrollment: 601
Study Start Date: August 2010
Study Completion Date: March 2013
Primary Completion Date: March 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: CR+G
conventional risk counseling (lifetime risk, fasting plasma glucose, and family history) plus genetic testing for type 2 diabetes
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.
Active Comparator: CR+EYE
conventional risk counseling (lifetime risk, fasting plasma glucose, and family history) plus eye disease counseling
Behavioral: Conventional risk counseling
Risk based on lifetime risk, fasting plasma glucose results, and family history.
Behavioral: eye disease counseling
addresses risk for age-related macular degeneration, glaucoma, cataracts

Detailed 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.

  Eligibility

Ages Eligible for Study:   21 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01060540

Locations
United States, North Carolina
Durham VA Medical Center HSR&D COE
Durham, North Carolina, United States, 27705
Sponsors and Collaborators
Duke University
Investigators
Principal Investigator: Corrine I. Voils, PhD Department of Veterans Affairs
  More Information

Publications:
Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Department of Veterans Affairs
ClinicalTrials.gov Identifier: NCT01060540     History of Changes
Other Study ID Numbers: IBD 09-039
Study First Received: January 29, 2010
Results First Received: April 16, 2014
Last Updated: July 11, 2014
Health Authority: United States: Federal Government

Keywords provided by Department of Veterans Affairs:
genetic screening

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases

ClinicalTrials.gov processed this record on August 28, 2014