Effects of selected antidiabetics on weight loss--a retrospective database analysis

In published studies metformin was often associated with weight loss in type 2 diabetes patients. Until now, no epidemiological studies have directly compared the effects of DPP-4 and GLP-1 versus metformin on weight loss. Our study is a comparison of sulfonylurea, DPP-4 and GLP-1 with metformin regarding body weight in type 2 diabetes patients.

Data from 2641 patients initiated therapy with either metformin, sulfonylurea, DPP-inhibitors or GLP-1 with baseline BMI >30 were retrospectively analyzed (Disease Analyzer Germany: 11/2008-10/2012). Comparison was performed for the weight change after 1 year of therapy compared with the last value prior to therapy. Differences between SU, DPP-4, GLP-1 versus metformin were estimated using regression model adjusted for age, gender, health insurance status, defined co-diagnoses and body weight at baseline.

In absolute values, metformin patients lost an average of 2.6 kg, subjects treated with SU gained 0.3 kg, body weight in the DPP-4 group decreased by 1.8 kg and GLP-1 patients lost 3.3 kg in body weight after 1 year. After adjustment for other variables, comparisons with metformin revealed the following results: SU +3.4 kg (p < 0.001), DPP-4 +1.0 kg (p = 0.003) and GLP-1 -0.4 kg (p = 0.589).

Our study showed that GLP-1 treatment was comparable to metformin regarding the weight reduction, while sulfonylurea and DPP-4 are inferior in this regard.