Location: Children's Nutrition Research CenterTitle: Effectiveness of lifestyle interventions for individuals with severe obesity and type 2 diabetes Author
Submitted to: Diabetes Care
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/11/2011
Publication Date: 8/11/2011
Citation: Unick, J.L., Beavers, D., Jakicic, J.M., Kitabchi, A.E., Knowler, W.C., Wadden, T.A., Wing, R.R., Foreyt, J.P. 2011. Effectiveness of lifestyle interventions for individuals with severe obesity and type 2 diabetes. Diabetes Care. 34(10):2152-2157. Interpretive Summary: Rates of very severe obesity continue to increase while the prevalence of overweight and mild obesity has stabilized in recent years. This subgroup has primarily been excluded from clinical weight loss trials due to comorbid conditions and upper BMI exclusionary criteria. Very severe obesity is associated with a significantly higher prevalence of comorbid conditions and higher mortality rates compared with overweight and moderately obese populations. Severe obesity not only puts individuals at risk for developing diseases such as diabetes and cardiovascular disease, but once an individual develops Type 2 diabetes, life expectancy maybe shortened by as much as 20 years. Since extreme categories of obesity comprise the most rapidly growing and high risk segment of the overweight population, effective methods for treatment must be identified and implemented. There are three levels of obesity: class I, moderate obesity, and class II, severe obesity, and class III, very severe obesity. The effect of Look AHEAD, an intensive lifestyle intervention (ILI), on weight loss, cardiovascular disease (CVD) risk, and program adherence for persons with type 2 diabetes who were very severely obese was compared to participants in overweight, class I obese, or class II obese categories. At 1 year of participation very severely obese ILI members showed comparable results to class I and class II obese ILI members. All obese participants showed significantly greater weight loss as compared to the overweight participants. All BMI groups showed improvements in fitness, physical activity, cholesterol, risk factors for cardiovascular disease, diabetes indicators, and treatment session attendance did not differ among weight categories. The results of this study suggest that a behavioral weight loss program is an effective treatment option for the very severely obese population. A population that to this date has been presented with limited options for weight loss. Bariatric surgery is the present recommended treatment for the very severely obese. This treatment option is limited in scope and may not be an ideal for the very severely obese. Although effective, this procedure is performed on less than 1% of the very severely obese population each year. The evidence of this study indicates that behavioral weight loss programs provide an efficacious treatment for the increasing population of high-risk, very severely obese patients with type 2 diabetes.
Technical Abstract: Rates of severe obesity (BMI greater than or equal to 40 kg/m(2)) are on the rise, and effective treatment options are needed. We examined the effect of an intensive lifestyle intervention (ILI) on weight loss, cardiovascular disease (CVD) risk, and program adherence in participants with type 2 diabetes who were severely obese compared with overweight (BMI 25 to <30 kg/m(2)), class I (BMI 30 to <35 kg/m(2)), and class II (BMI 35 to <40 kg/m(2)) obese participants. Participants in the Action for Health in Diabetes (Look AHEAD) trial were randomly assigned to ILI or diabetes support and education (DSE). DSE participants received a less intense educational intervention, whereas ILI participants received an intensive behavioral treatment to increase physical activity (PA) and reduce caloric intake. This article focuses on the 2,503 ILI participants (age -58.6 +/- 6.8 years). At 1 year, severely obese participants in the ILI group lost 9.04 +/- 7.6% of initial body weight, which was significantly greater (P < 0.05) than ILI participants who were overweight (7.43 +/- 5.6%) and comparable to class I (8.72 +/- 6.4%) and class II obese (8.64 +/- 7.4%) participants. All BMI groups had comparable improvements in fitness, PA, LDL cholesterol, triglycerides, blood pressure, fasting glucose, and HbA(1c) at 1 year. ILI treatment session attendance was excellent and did not differ among weight categories (severe obese 80% vs. others 83%; P = 0.43). Severely obese participants in the ILI group had similar adherence, percentage of weight loss, and improvement in CVD risk compared with less obese participants. Behavioral weight loss programs should be considered an effective option for this population.