RT Journal Article SR Electronic T1 Maximum body mass index before onset of type 2 diabetes is independently associated with advanced diabetic complications JF BMJ Open Diabetes Research & Care JO BMJ Open Diab Res Care FD American Diabetes Association SP e002466 DO 10.1136/bmjdrc-2021-002466 VO 9 IS 2 A1 Harutoshi Ozawa A1 Kenji Fukui A1 Sho Komukai A1 Megu Y Baden A1 Shingo Fujita A1 Yukari Fujita A1 Takekazu Kimura A1 Ayumi Tokunaga A1 Hiromi Iwahashi A1 Junji Kozawa A1 Iichiro Shimomura YR 2021 UL http://drc.bmj.com/content/9/2/e002466.abstract AB Introduction The maximum body mass index (BMI) before onset of type 2 diabetes (MBBO) might be used to estimate a patient’s insulin secretion capacity. There have been few factors that can predict future diabetic complications at the time of diagnosis of diabetes mellitus. This study aimed to clarify the clinical usefulness of MBBO for predicting the development of advanced diabetic microvascular complications.Research design and methods This was a cross-sectional observational study. Of 1304 consecutively admitted patients with type 2 diabetes, we enrolled 435 patients for whom we could confirm their MBBO. Univariate and multivariate logistic regression analyses were performed to examine whether MBBO or BMI on admission was associated with advanced diabetic retinopathy or nephropathy. To evaluate the predictive performance of these indexes, we performed cross-validation in various models with MBBO or BMI and evaluated the areas under the curve (AUCs) yielded by these analyses.Results Univariate analyses suggested that MBBO was associated with advanced retinopathy and nephropathy, while BMI on admission was associated only with advanced nephropathy. In multivariate analyses, MBBO was significantly associated with advanced complications, while BMI on admission was not. For advanced diabetic retinopathy, the AUCs were 0.70–0.72, and for advanced nephropathy, the AUCs were 0.81–0.83. When comparing the AUCs among models, the models with MBBO sustained high predictive performance for diabetic complications.Conclusions MBBO was independently associated with advanced diabetic complications, while BMI on admission was not. Diabetic microvascular complications in patients with high MBBO could progress more rapidly. At the time of the diagnosis of diabetes mellitus, MBBO would enable us to predict the progress of diabetic complications.All data relevant to the study are included in the article. The datasets generated and analyzed during the current study are available from the corresponding author on reasonable request.