Weight gain in insulin‐treated patients by body mass index category at treatment initiation: n ew evidence from real‐world data in patients with type 2 diabetes

Aims To evaluate, in patients with type 2 diabetes ( T2DM ) treated with insulin, the extent of weight gain over 2 years of insulin treatment, and the dynamics of weight gain in relation to glycaemic achievements over time according to adiposity levels at insulin initiation. Materials and methods Patients with T2DM (n = 155 917), who commenced insulin therapy and continued it for at least 6 months, were selected from a large database of electronic medical records in the USA . Longitudinal changes in body weight and glycated haemoglobin ( HbA1c ) according to body mass index ( BMI ) category were estimated. Results Patients had a mean age of 59 years, a mean HbA1c level of 9.5%, and a mean BMI of 35 kg/m 2 at insulin initiation. The HbA1c levels at insulin initiation were significantly lower (9.2‐9.4%) in the obese patients than in patients with normal body weight (10.0%); however, the proportions of patients with HbA1c >7.5% or >8.0% were similar across the BMI categories. The adjusted weight gain fell progressively with increasing baseline BMI category over 6, 12 and 24 months (p < .01). The adjusted changes in HbA1c were similar across BMI categories. A 1% decrease in HbA1c was associated with progressively less weight gain as pretreatment BMI rose, ranging from a 1.24 kg gain in those with a BMI <25 kg/m 2 to a 0.32 kg loss in those with a BMI > 40 kg/m 2 . Conclusions During 24 months of insulin treatment, obese patients gained significantly less body weight than normal‐weight and overweight patients, while achieving clinically similar glycaemic benefits. These data provide reassurance with regard to the use of insulin in obese patients.