OBJECTIVE Weight loss is recommended for overweight patients with diabetes but avoidance of weight gain may be a more realistic goal. We calculated the 4-year economic impact of maintaining body weight versus gaining weight.

RESEARCH DESIGN AND METHODS Among 8,154 patients with type 2 diabetes, we calculated weight change as the difference between the first body weight measure in 2010 and the last measure in 2013 and calculated mean glycated hemoglobin (A1C) from all measurements from 2010 to 2013. We created four analysis groups: weight change <5% and A1C <7%; weight gain ≥5% and A1C <7%; weight change <5% and A1C ≥7%; and weight gain ≥5% and A1C ≥7%. We compared change in medical costs between 2010 and 2013, adjusted for demographic and clinical characteristics.

RESULTS Patients who maintained weight within 5% of baseline experienced a reduction in costs of about $400 regardless of A1C. In contrast, patients who gained ≥5% of baseline weight and had mean A1C ≥7% had an increase in costs of $1,473 (P < 0.001). Those who gained >5% of their baseline weight with mean A1C <7% had a modest increase in costs ($387, NS).

CONCLUSIONS Patients who gained at least 5% of their baseline body weight and did not maintain A1C <7% over 4 years experienced a 14% increase in medical costs, whereas those who maintained good glycemic control had a mean cost increase of 3.3%. However, patients who maintained weight within 5% of baseline had costs that were ∼5% lower than baseline. Avoidance of weight gain may reduce costs in the long-term.