Lifestyle Intervention Program for Type 2 Diabetes

Compared to non-Hispanic whites, African Americans have a higher prevalence of type 2 diabetes and experience a disproportionate rate of diabetes complications and hospitalizations, especially in a highly disadvantaged population. “One way of reducing this disparity would be to improve glycemic control among African Americans, which can be achieved through changes in diet and physical activity as well as medication adherence, but making these changes can be hard for underserved African American populations, and in general, lifestyle interventions are less effective with African American populations,” said lead investigator Elizabeth B. Lynch, PhD, Associate Professor, Department of Preventative Medicine, Rush University Medical Care Center, Chicago, IL.

Dr. Lynch noted that past lifestyle intervention programs have resulted in glycemic control in the short term (6 months), but those changes were not sustained beyond 6 months. Dr. Lynch and colleagues designed a study to test the impact of an intensive lifestyle intervention program on the blood glucose levels in a low-income patient population, with the aim of sustaining improved glycemic control at 12 months.

“The key, novel component of this intervention was a cognitively tailored nutrition education. This education curriculum was based on a series of studies that were done using a cognitive anthropological method with low-income African Americans looking at both needs and knowledge about the relationship of food and health. We used those studies to design the intervention with the aim of reducing cognitive load among participants while they were learning new information about nutrition, so essentially making the information easier to understand.”

The study recruits were African American patients attending five outpatient clinics in the Cook County Health and Hospitals System in Chicago who had uncontrolled type 2 diabetes (A1c >7%). The 211 participants selected were 55±10 years of age, had a mean A1c of 9%, were 70% female, had an average BMI of 35.6±8, and a diabetes duration of 11.3±9 years. Forty-five percent were on insulin and 91% had co-morbid hypertension. Sixty-five percent of the participants were uninsured, 58% had an income ≤$20,000 per year, and 39% had low health literacy. Their dietary intake was high in saturated fat, low in fiber, moderate in carbs, and there was an under consumption of fruits, vegetables, and dairy. Also the group was very sedentary.

The participants were randomly assigned to the Lifestyle Improvement through Food and Exercise (LIFE) program, an intensive diabetes and self-management arm (n=106), or a control arm (n=105) that received standard of care diabetes education. Retention in the year-long program was 93% in the LIFE arm and 95% in the control arm.

Over the course of the program, patients in the LIFE arm were given 28 group counseling sessions with dieticians and peer supporters in a community setting. For the first four months, the group met weekly, then every other week for the next four months, and monthly for the remaining four months of the program. The sessions involved interactive and culturally-tailored diabetes nutrition education, group exercise sessions, and social support which involved supportive group discussions and problem solving assistance as well as weekly phone calls from peer supporters in their community. They were taught how to monitor and interpret their blood glucose levels in order to actively manage their diabetes. Over 50% of the LIFE group attended a majority of the sessions.

In the control arm, the group participated in two diabetes self-management education classes led by a registered dietician. This occurred during the first six months of the program. While this level of education meets national standards, it is not usual care for diabetes patients in the Cook County Health and Hospitals System. Almost 70% of the control group attended both sessions.

At six months, patients in the LIFE arm had a significantly greater A1c reduction (-0.76 vs. -0.21 in control, P=0.026), as well as a higher percentage of participants who saw a decline of more than 0.5% in their average blood glucose levels (63% vs. 42% in the control group, P=0.005). These differences, however, were not maintained at 12 months. By the end of the study, patients in the control group also had a decrease in A1c (-0.63 for the LIFE group vs. -0.45 for the control, P=0.47), and an equal number of patients in each group achieved a reduction in A1c of more than 0.5% (53% in the LIFE group vs. 51% in the control group, P=0.89). A greater number of participants in the LIFE group achieved glycemic control at 12 months (61% in the LIFE group vs. 39% in the control group, P=0.16), but that difference was not statistically significant. Medication adherence improved in the control group but not the LIFE group.

“We did see that there was a greater increase in nutrition knowledge in the treatment group than in the control group, but that greater difference in knowledge did not translate into significant differences in dietary behavior, which is what we had hoped would lead to increased changes in A1c.” Dr. Lynch noted that “…medication adherence was emphasized to a greater extent, relatively speaking, in our control group than it was in our treatment group. This may be a more simple and effective strategy for this population to engage in in order for them to reduce their A1c.”

Session 282-OR. Lifestyle Improvement through Food and Exercise (LIFE): Randomized Trial of a Self-Management Intervention for Underserved African Americans with Type 2 Diabetes. ADA Scientific Sessions, New Orleans, LA. June 12, 2016.