Long-term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals With Type 2 Diabetes Mellitus

Abstract

Objective Lifestyle interventions produce short-term improvements in glycemia and cardiovascular disease (CVD) risk factors in individuals with type 2 diabetes, but no long-term data are available. We examined the effects of a lifestyle intervention on changes in weight, fitness and cardiovascular (CVD) risk factors over 4 years. Research Design and Methods Look AHEAD is a multi-center randomized clinical trial comparing the effects of intensive lifestyle intervention (ILI) and diabetes support and education (DSE, control group) on the incidence of major CVD events in 5145 individuals with type diabetes, aged 45 to 76 years, who were overweight or obese (BMI > 25 kg/m2). Participants have ongoing intervention and annual assessments. Results Averaged across four years of follow-up, participants in ILI had greater percent weight losses than those in DSE (−6.15% vs −0.88%, p<.0001) and greater improvements in fitness (12.74% vs. 1.96%, p < .0001), HbA1c (A1c, −0.36% vs. 0.09%, p<.0001), systolic blood pressure (SBP, −5.33 vs. −2.97 mmHg, p<.0001), diastolic blood pressure (DBP, −2.92 vs. −2.48 mmHg, p<.012), HDL-cholesterol (HDL-C, 3.67 vs. 1.97 mg/dl, p<.0001), and triglycerides (−25.56 vs. −19.75 mg/dl, p<.0006). Reductions in LDL-C were greater in DSE than ILI (−11.27 vs. −12.84 mg/dl, p=.009), but adjusted for medication use, changes in LDL-C did not differ between the two groups. Although the greatest benefits were often seen at 1 year, ILI participants still had greater improvements than DSE in weight, fitness, HbA1c, SBP, and HDL-C at 4 years. Conclusions Intensive lifestyle intervention can produce and maintain significant weight losses and improvements in fitness in individuals with type 2 diabetes. Across four years of follow-up, those in ILI had better overall levels of glycemic control, blood pressure, HDL-C and triglycerides, and thus spent considerable time with lower CVD risk. Whether this translates to reduction in CVD events will ultimately be addressed by the Look AHEAD study.

Effects of a Health‐Partner Intervention on Cardiovascular Risk

“…Our findings are consistent with previous trials utilizing lifestyle interventions in subjects with specific risk factors or with known CVD 30, 31, 32, 33, 34, 35. However, these studies have not been performed in an otherwise relatively healthy population where the goal was not prevention of disease, but to maintain ideal health.…”

“…It is known that aggressive and focused intervention on diet and exercise can reduce risk of diabetes mellitus 30, 32, 44. Often, these interventions require intense dietary and lifestyle modifications that are time‐consuming and expensive to implement because they require trained staff and their long‐term cost‐effectiveness remains debatable 45, 46, 47.…”

Weight maintenance: challenges, tools and strategies for primary care physicians

“…The Look AHEAD (Action for Health in Diabetes) study assessed the effects of intensive lifestyle intervention (ILI) on clinically important health outcomes in people with overweight or obesity with type 2 diabetes 59, 60, 61. Participants were randomly assigned to one‐on‐one ILI or conventional diabetes support and education (DSE) 59.…”

“…Participants were randomly assigned to one‐on‐one ILI or conventional diabetes support and education (DSE) 59. ILI included diet modification and physical activity to induce and maintain ≥7% weight loss at 1 year and beyond 59, 60. ILI participants had goals of 1,200–1,800 kcal d −1 , based upon initial weight, and physical activity of >175 min week −1 60.…”

“…ILI included diet modification and physical activity to induce and maintain ≥7% weight loss at 1 year and beyond 59, 60. ILI participants had goals of 1,200–1,800 kcal d −1 , based upon initial weight, and physical activity of >175 min week −1 60. At 1 year, the ILI group, compared with the DSE group, had lost a greater percentage of their initial weight (−8.6% vs. −0.7%); had improved fitness (assessed by treadmill test); had improvements in HbA 1c , systolic and diastolic blood pressure, triglyceride, high‐density lipoprotein (HDL)‐cholesterol and urine albumin/creatinine; and had a reduced need for type 2 diabetes, hypertension and lipid‐lowering medications 59.…”