Diabetes, Metabolic Syndrome and Obesity (Mar 2020)
Influence of Diabetic Retinopathy on the Relationship Between Body Mass Index and Mortality in Patients with Poorly Controlled Type 2 Diabetes
Abstract
Yu-Hsuan Li,1,2 Wayne Huey-Herng Sheu,1,3,4 I-Te Lee1,3,5,6 1Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 40705, Taiwan; 2Graduate Institute of Data Science, Taipei Medical University, Taipei 11031, Taiwan; 3School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan; 4Rong Hsing Research Center for Translational Medicine, College of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan; 5School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; 6College of Science, Tunghai University, Taichung 40704, TaiwanCorrespondence: I-Te LeeDivision of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, 1650 Taiwan Boulevard, Sect. 4, Taichung 40705, TaiwanTel +886-4-23741300Fax +886-4-23593662Email [email protected]: An “obesity paradox” has been observed in patients with type 2 diabetes. However, the optimal body mass index (BMI) for survival may be influenced by the stage of diabetes. We examined the relationship between BMI and mortality in patients with type 2 diabetes and the influence of diabetic retinopathy (DR).Patients and Methods: This is a retrospective cohort composing patients with type 2 diabetes who were admitted due to poor glucose control. Presence of DR was confirmed by ophthalmologists. The primary outcome was all-cause mortality. The association between BMI and mortality was assessed using a Cox proportional hazards model with adjustment for age, sex, and traditional risk factors.Results: A total of 2053 patients were enrolled. Over median follow-up of 6.7 years, there were 1060 deaths. Patients were classified into five categories based on admission BMI (kg/m2): < 18.5, 18.5‒23, 23‒25, 25‒27 (reference), 25‒30 and > 30. Mortality risk was significantly higher in the < 18.5 kg/m2, 18.5– 23 kg/m2, and 23– 25 kg/m2 categories than in the reference category (P < 0.001). The similar obesity paradox was observed in the subgroup of patients without DR. However, in patients with DR, only patients with BMI < 18.5 kg/m2 had significantly increased mortality than those in the reference category. The presence of DR significantly modified the shape of the association between BMI and mortality (P = 0.019).Conclusion: The obesity paradox exists in patients with poorly controlled type 2 diabetes. The presence of DR appears to significantly influence the shape of the association between BMI and mortality.Keywords: cohort, inpatient, obesity, paradox, overweight, retrospective
