Primary Care-Based Diabetes Prevention Interventions Reduce BMI

Using the Diabetes Prevention Program (DPP) model, a study of 2 different lifestyle interventions delivered in a primary care setting showed a reduction in body mass index (BMI) in overweight or obese adults with prediabetes, metabolic syndrome, or both [JAMA Intern Med. 2013;173(2):113-121].

Nearly 70% of adults in the United States are overweight or obese. Because this patient population is at increased risk for diabetes, evidence-based guidelines recommend effective lifestyle intervention for weight management and disease prevention. The DPP lifestyle intervention program reduced the incidence of type 2 diabetes by 58% among high-risk individuals; however, it has not been adequately translated into primary care.

The E-LITE (Evaluation of Lifestyle Interventions to Treat Elevated Cardiometabolic Risk in Primary Care) was a 3-arm, primary-care based, randomized trial designed to evaluate the effectiveness of 2 adapted DPP lifestyle interventions that compared both a coach-led, in-person weekly group intervention and a self-reported DVD intervention with usual care. Participants were recruited between July 2009 and June 2010 from a single primary care clinic within the Silicon Valley that is part of a large multidisciplinary group practice in the San Francisco Bay Area. Inclusion criteria included age of ≥18 years, a BMI of ≥25, and the presence of prediabetes or metabolic syndrome. Participants with serious medical or psychiatric conditions or special life circumstances were excluded.

E-LITE included 241 participants who were randomized to 1 of 3 groups: (1) a coach-led, group-delivered intervention (n=79), (2) a self-directed DVD intervention (n=81), or (3) usual care (n=81). All participants continued to receive standard medical care. Participants in the usual care group received no information about weight loss or weight-loss goals. Those in both intervention groups completed a 3-month intensive phase followed by a 12-month maintenance phase. During the 3-month intensive phase, the DPP-based behavioral weight loss curriculum was delivered by lifestyle coach-led small groups or home-based DVD. In the maintenance phase, participants in both interventions received lifestyle change coaching and support via emails.

The primary end point was a change in BMI from baseline to 15 months. At baseline, the mean participant age was 52.9 years, and the mean BMI was 32. Women accounted for slightly less than half (47%), and the majority (78%) were non-Hispanic white. Approximately 54% had prediabetes, 87% had metabolic syndrome, and 41% had both conditions.

At 15 months, the results showed that the change in BMI was significant for the intervention groups compared with usual care. The mean decrease in BMI was 2.2 for the coach-led group (P<.001 vs usual care) and 1.6 for the self-directed group (P=.02 vs usual care) compared with 0.9 for usual care. The DPP program included a final weight-loss goal of 7%. Of the study participants who achieved this goal, 37% (P=.003) and 35.9% (P=.004) were in the coach-led and self-directed groups, respectively, versus 14.4% in the usual care group. Patients in both intervention groups also achieved greater improvement in waist circumference and fasting plasma glucose level.

The researchers noted the following 3 study limitations: the participants were primarily of high socioeconomic status and from a single primary care clinic; replacement of missing weights with clinical values recorded in the electronic health record or self-reported weights may have introduced bias; and the study was only 15 months and was not designed to evaluate event-based outcomes or cost-effectiveness.