Effectiveness of Lifestyle Intervention for Type 2 Diabetes in Primary Care: the REAL HEALTH-Diabetes Randomized Clinical Trial

Abstract

Background: Intensive lifestyle interventions (LI) improve outcomes in obesity and type 2 diabetes but are not currently available in usual care.

Objective: To compare the effectiveness and costs of two group LI programs, in-person LI and telephone conference call (telephone LI), to medical nutrition therapy (MNT) on weight loss in primary care patients with type 2 diabetes.

Design: A randomized, assessor-blinded, practice-based clinical trial in three community health centers and one hospital-based practice affiliated with a single health system.

Participants: A total of 208 primary care patients with type 2 diabetes, HbA1c 6.5 to < 11.5, and BMI > 25 kg/m2 (> 23 kg/m2 in Asians).

Interventions: Dietitian-delivered in-person or telephone group LI programs with medication management or MNT referral.

Main measures: Primary outcome: mean percent weight change.

Secondary outcomes: 5% and 10% weight loss, change in HbA1c, and cost per kilogram lost.

Key results: Participants' mean age was 62 (SD 10) years, 45% were male, and 77% were White, with BMI 35 (SD 5) kg/m2 and HbA1c 7.7 (SD 1.2). Seventy were assigned to in-person LI, 72 to telephone LI, and 69 to MNT. The mean percent weight loss (95% CI) at 6 and 12 months was 5.6% (4.4-6.8%) and 4.6% (3.1-6.1%) for in-person LI, 4.6% (3.3-6.0%) and 4.8% (3.3-6.2%) for telephone LI, and 1.1% (0.2-2.0%) and 2.0% (0.9-3.0%) for MNT, with statistically significant differences between each LI arm and MNT (P < 0.001) but not between LI arms (P = 0.63). HbA1c improved in all participants. Compared with MNT, the incremental cost per kilogram lost was $789 for in-person LI and $1223 for telephone LI.

Conclusions: In-person LI or telephone group LI can achieve good weight loss outcomes in primary care type 2 diabetes patients at a reasonable cost.

Clinical trial registration: ClinicalTrials.gov Identifier: NCT02320253.

Keywords: cost-effectiveness; lifestyle intervention; primary care; type 2 diabetes; weight loss interventions.

Conflict of interest statement

LMD serves on the Advisory Boards of Omada Health, JanaCare, and WW, Inc. DJW serves on two Data Monitoring Committees for clinical trials sponsored by NovoNordisk.

Figures

Figure 1

CONSORT diagram.

Figure 2

One-year weight loss: mean (a), 5% (b), and 10%(c).

Figure 3

Cost-effectiveness acceptability curves for comparisons across study arms. Likelihood (y-axis) that the first arm would be preferred to the second arm at a given willingness-to-pay threshold (x-axis). Estimates based on 100,000 simulations. LI, lifestyle intervention; MNT, medical nutrition therapy.