Abstract
INTRODUCTION: This article evaluates the potential long-term effect of two different color indication methods for self-monitoring of blood glucose (SMBG), the color record (CR) and color display (CD), on metabolic parameters in insulin-treated type 2 diabetes in a post-intervention period. METHODS: 101 participants with type 2 diabetes who completed the Color IMPACT study were enrolled in a 2-year comparison follow-up study. Participants continued SMBG with their usual diabetes care. The study outcomes were differences in change in HbA1c levels, blood pressure (BP), body weight and lipid profiles between the CR and non-CR arms and the CD and non-CD arms during a 1- and 2-year period of the study. RESULTS: 98 participants were analyzed. Reductions in HbA1c levels, systolic BP and low-density lipoprotein cholesterol levels were maintained in the CR arm by - 0.40% (95% CI: - 0.73 to - 0.06, p = 0.020), -1 3.2 mmHg (95% CI: - 24.1 to - 2.3, p = 0.019), - 11.4 mg/dl (95% CI: - 18.1 to - 4.6, p = 0.001), respectively, in a 1-year period. However, HbA1c and BP returned to the baseline levels during an additional 1-year period. In contrast, there were no significant changes in outcome in the CD arm during the study period. CONCLUSION: Intervention promoting self-action such as the color record method in SMBG sustains a beneficial effect on metabolic parameters after the intervention. This long-term effect is helpful for people with type 2 diabetes to manage their diabetes ABCs (HbA1c, BP, cholesterol) and to prevent diabetic complications. TRIAL REGISTRATION: UMIN clinical trials registry identifier, UMIN000006865.