August Journal Blog: ENHANCE Trial

Biophysiological outcome of the Enhancing Adherence in

Type 2 Diabetes (ENHANCE) Trial

(see references for links to articles)

Introduction

It has been well established that cardiovascular disease is the leading cause of morbidity and mortality among diabetics in the United States (American Diabetes Association, 2012). Current recommendations for reducing CVD in type 2 diabetic patients are mostly aimed at reduction of these individual risk factors: HbA1c, lipids, blood pressure, and weight for those who are obese.

Treatment methods for achieving these biophysical targets have largely included aggressive medication therapies. However, recent research trials, such as the well-known ACCORD trial, have indicated that aggressive medication therapies have not significantly improved CVD outcomes among type 2 diabetic patients and may actually be dangerous for those who have a long history of uncontrolled hyperglycemia. As a result of discouraging findings like this, it has been proposed that a focus on lifestyle modifications might be more appropriate for type 2 diabetes management.

One behavioral modification strategy that has shown great success for weight loss, and might be applicable to diabetes management, is the act of self-monitoring. In a review of self-monitoring and weight loss studies over the last two decades, several methods of self-monitoring including handwritten journaling and the use of technology-based programs were usually fairly equal in success regarding weight-loss outcomes (Burke et. al, 2011). However, in one study that utilized PDAs (personal digital assistant), the addition of a daily feedback messaging system showed superiority in self-monitoring.

The ENHANCE Study

The ENHANCE study was formulated to evaluate a behavioral intervention featuring technology-based self-monitoring on biophysiological outcomes of glycemic control and markers for CVD risk. Participants for the study were categorized according to their baseline kidney function (eGFR) and level of glycemic control (HbA1c of <8% good or ≥8% poor). Participants were randomly assigned treatment groups within each strata. Most participants (90.4%) were on one or more prescriptions of diabetic medications at the time of the study. 69.2% were on antihypertensive drugs and 56.4% were taking lipid-lowering medications.

Both group participants were given glucose monitors and enough strips to perform ≥ 2 capillary blood glucose (CBG) measures per day and a pedometer with a target level of physical activity at 10,000 steps per day. Measurements were obtained from all participants at baseline, 3 months, and 6 months. These measurements included glycated hemoglobin, fasting serum glucose, lipid levels, blood pressure, weight, body mass index, and waist circumference.  

There were two treatments for the ENHANCE study called the “behavioral intervention group” and the “attention control group”.

 Behavioral intervention group treatment:

1.      Group counseling sessions guided by Social Cognitive Theory – weekly for months 1 and 2, biweekly months 3 and 4, and monthly during months 5 and 6.

2.      PDA (Personal Digital Assistant) - a hand-held, self-monitoring device in which participants could track daily energy targets, balance their intake of proteins, fats and carbohydrates, monitor their medication management, and track physical activity. The use of PDAs was intended to enhance self-efficacy in diabetes management by providing an easy way to provide instant feedback about meal goals, overall energy input vs. output, and connections between carbohydrate and saturated fat intake and glycemic control.

3.      CBG results and PDA diet and physical activity were uploaded at each session. Printed reports and verbal feedback from clinical diabetes educators were given. Instructions on how to interpret these results was given to each participant and goals were set for the next meeting.

Attention Group Treatment:

1.      Monthly contact with the study team.

2.      Months 1, 3 and 5 – attended group seminars about general diabetes education.

3.      Months 2,4, and 6 – participants received a lay diabetes magazine

The ENHANCE study hypothesized that, “[C]ompared to those randomized to the attention control group, intervention group participants would demonstrate improved glycemia, serum lipid levels, blood pressure, weight, body mass index (BMI), and waist circumference” (Sevick et al., 2012). However, the results of this study did not work out as hypothesized. In reality, all groups experienced a significant improvement in all biophysiological outcomes. The researchers of this study indicated that the majority of the population studied was predominantly white, female, employed, well-educated, and insured. The researchers suspect that because of these participant characteristics and their willingness the volunteer for the study, the participants selected for the study were already highly motivated for a lifestyle change, no matter what the treatment.

Although this study fails to support any evidence that intense technology-based self-monitoring devices are any more effective than standard behavioral methods, there was one important finding that can be taken away from this study. This finding compared the degree of reduction in glycosylated hemoglobin levels between the ACCORD study and the ENHANCE study. The ACCORD study, which utilized intensive medication management of CVD risk factors, accomplished an absolute reduction of 1.4% at 4 months and 1.7% at 1 year. The ENHANCE study achieved 1.5% at 3 months and 1.8% at 6 months on behavioral methods alone.

Summary

            Since aggressive medication therapies have not significantly improved CVD outcomes among type 2 diabetic patients, professionals are trying to identify methods of behavioral interventions that may be more effective. As weight loss success is often associated with the practice of self-monitoring, some of the same techniques are being considered for lifestyle management of diabetes. The ENHANCE study was designed to consider how a self-monitoring device could improve the biophysical outcomes of type 2 diabetics compared to traditional behavioral strategies. The study found that both the control and the intervention group improved general lifestyle management with no significant difference in the two behavioral strategies. However, the importance of comparable glycemic control findings between the ACCORD study and the ENHANCE study suggest that behavioral methods can be just as effective in diabetes management as medication therapies. The authors suggest that future studies could focus on the use of Smartphone applications in self-management of diabetes.  

References

·         Burke, L.E., Wang, J., & Sevick, M.A. (2011). Self-Monitoring in weight-loss: a systematic review of the literature. Journal of the American Dietetic Association. 111, 92-102. Retrieved from: http://download.journals.elsevierhealth.com/pdfs/journals/0002-8223/PIIS0002822310016445.pdf

·         Sevick, M.A., Korytkowski, M., Stone, R.A., Piraino, B., Ren, D., Sereika, S.,Wang, Y., Steenkiste, A., Burke, L.E. (2012). Biophysiological outcome of the Enhancing Adherence in Type 2 Diabetes (ENHANCE) Trial. Journal of the Acadmey of Nutrition and Dietetics, 112, 1147-1157. Retrieved from: http://www.andjrnl.org/article/S2212-2672(12)00628-4/fulltext