Background: Lifestyle interventions (LI) to treat obesity and type 2 diabetes improve medical outcomes but are not currently available in usual care.

Objective: To compare the effectiveness of 2 LI programs: in-person group (IP) and telephone conference call (TCC) to medical nutrition therapy (MNT), on weight loss at 1 year in a practice-based RCT. The LI programs are adapted from Look AHEAD’s LI program and delivered in 3 community health centers and one hospital-based practice.

Methods: Patients with type 2 diabetes, HbA1c 6.5-11.5, BMI > 25 (> 23 in Asians) kg/m2 (n=211) were randomly assigned to IP (n=70), TCC (n=72), or MNT (n=69). Trained registered dietitians delivered 25 lifestyle sessions in the first year. MNT participants had facilitated referral for outpatient dietitian visits (usual care).

Results: Participants were 62 ± 10 years, 45% male, 77% white, with BMI 35 ± 6 kg/m2, diabetes duration 10 ± 8 years and HbA1c 7.7 ± 1.2%; 66% of IP and 72% of TCC attended >18/25 sessions. Mean percent weight change at 6 and 12 months was -5.6 ± 4.9 and -4.6 ± 6.1 in IP, -4.6 ± 5.8 and -4.8 ± 6.1 in TCC, and -1.1 ± 3.7 and -2.0 ± 4.1 in MNT, with statistically significant differences between both LI arms and MNT (P<0.01 at both timepoints), but not between the two LI arms at 6 and 12 months. HbA1c improved in all participants with no statistically significant differences among study arms. At 6 and 12 months, 42 and 45% of IP participants had stopped or reduced a glucose-lowering medication, compared to 23% of MNT participants at both timepoints (P=0.03 and 0.01, respectively). No significant difference in medication reduction was observed between TCC participants (33 and 36% at 6 and 12 months) and the other two groups.

Conclusions: IP and TCC lifestyle interventions can achieve equivalent outcomes in terms of clinically significant weight loss, improvement in glycemic control, and participant engagement. The TCC delivery format may extend program reach.


L.M. Delahanty: Advisory Panel; Self; Jana Care Inc., Omada Health, Inc., Weight Watchers International, Inc. Y. Chang: None. B.C. Porneala: None. J. McCarthy: None. V.M. Goldman: None. D.E. Levy: None. D.J. Wexler: Other Relationship; Spouse/Partner; APOLO1BIO.


National Institute of Diabetes and Digestive and Kidney Diseases

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