Healthy Eating and Active Living for Diabetes-Glycemic Index (HEALD-GI): Protocol for a Pragmatic Randomized Controlled Trial

JMIR Res Protoc. 2019 Mar 6;8(3):e11707. doi: 10.2196/11707.

Abstract

Background: Rigorous evidence is needed regarding the best approach for increasing the uptake of Diabetes Canada's evidence-based recommendations to include low-glycemic index (GI) foods in daily meal planning as an effective dietary self-care strategy for glycemic control among people with type 2 diabetes (T2D).

Objective: This study aims to present the study design and baseline data from the Healthy Eating and Active Living for Diabetes-Glycemic Index (HEALD-GI) trial, which was designed to evaluate the effectiveness of an enhanced GI-targeted nutrition education on GI-related knowledge and mean daily GI among adults with T2D in Edmonton, Alberta.

Methods: We used a pragmatic randomized controlled trial design and allocated 67 adults (aged ≥18 years) with T2D living in Edmonton, Alberta, Canada, to a control group that received standard printed copies of Canada's Food Guide and Diabetes Canada's GI resources or to an intervention group that received the same materials, plus a customized Web-based platform with 6 self-directed learning modules and print material. Each module included videos, links to reliable websites, chat rooms, and quizzes. Evidence-based GI concept information included GI values of foods and low-GI shopping, recipes, and cooking tips by a registered dietitian. In addition, support through email, text messaging (short message service), phone calls, or postal mail was provided to reinforce participants' learning. The primary outcome, average dietary GI, was assessed using 3-day food records. Additional measures including GI knowledge and self-efficacy, glycated hemoglobin (HbA1c), lipids, systolic blood pressure, body mass index (BMI; weight, height), waist circumference, and computer proficiency were assessed at baseline and at 3-month postintervention.

Results: Between November 2017 and February 2018, we contacted adults (aged ≥18 years) with T2D living in Edmonton, Alberta, screened and recruited eligible participants into the study. All data collection ended in June 2018. Overall, 64% (43/67) participants were males; mean age was 69.5 (SD 9.3) years, with a mean diabetes duration of 19.0 (SD 13.7) years. Mean BMI was 30.1 (SD 5.7) kg/m2, and mean HbA1c value was 7.1% (SD 1.2%). Data analysis was completed in December 2018.

Conclusions: The GI concept is often difficult to teach. The HEALD-GI study aims to provide evidence in support of an alternative approach to translating the GI concept to adults with T2D. Findings from this study may help registered dietitians to better disseminate low-GI dietary recommendations using efficient and cost-effective, patient-centered approaches. Furthermore, evidence generated will contribute to addressing some of the controversies regarding the clinical usefulness of the GI concept.

International registered report identifier (irrid): DERR1-10.2196/11707.

Keywords: glycemic index; randomized controlled trial; type 2 diabetes mellitus.