Comparison among criteria to define successful weight-loss maintainers and regainers in the Action for Health in Diabetes (Look AHEAD) and Diabetes Prevention Program trials

Background: Given the low rates of successful weight maintenance after lifestyle-induced weight loss, it is critical to develop approaches that distinguish successful weight-loss maintainers from regainers. Objective: The aim of this study was to compare published categorization criteria that differentiate maintainers and regainers via quantitative agreement. Design: The study used publicly available data from Look AHEAD (Action for Health in Diabetes; n = 1791) and Diabetes Prevention Program (DPP; n = 613) participants with >= 3% initial weight loss after lifestyle interventions and 4-y follow-up data. Eight previously published criteria defining maintainers and regainers were compared with respect to number of participants and concordance via agreement statistics. Criteria were assessed separately among those with 3-9% and >= 10% initial weight loss. Results: Regainers had higher body weight at year 4 than did maintainers (mean difference range: 6.6-11.9 kg in Look AHEAD; 11.5-14.6 kg in DPP; P < 0.0001). Assessing concordance among criteria, agreement was dependent on initial weight loss. Among those with 3-9% initial weight loss in both cohorts, 9 of 28 comparisons were concordant (agreement >= 80%). Among those with >= 10% initial weight loss, 7 of 28 comparisons in Look AHEAD and 13 of 28 in the DPP were in high agreement. The definition of successful weight-loss maintenance "regaining <= 25% of initial weight loss during maintenance" showed high agreement with the most commonly used definition of "staying >= 10% below initial weight" among those with >= 10% initial weight loss (agreement: 85.0% in Look AHEAD; 87.4% in DPP). The same definition of <= 25% regain showed high agreement with the definition of staying >= 5% below initial weight among those with 3-9% initial weight loss (agreement: 91.6% in Look AHEAD; 90.5% in DPP). Conclusions: Although all of the criteria discriminated on the basis of weight loss, many showed low agreement, which limited cross-study comparisons. Among criteria with high agreement, the definition of successful weight maintenance "regaining <= 25% of initial weight loss during maintenance" is a preferred definition of success, given the realistic challenges of maintaining 100% weight loss and flexible application in populations with high initial weight-loss variations. This trial was registered at clinicaltrials. gov as NCT00017953 (Look AHEAD) and NCT00004992 (DPP).