Relative Fat Mass, a new tool for measuring obesity, could predict the complications of type 2 diabetes

Aim/background: Obesity is a chronic disease contributing to many metabolic illnesses, in particular type 2 diabetes. The Relative Fat Mass (RFM) is a tool recently introduced for obesity which better predicts the level of visceral fat than the Body Mass Index (BMI). The aim of this study is to determine whether RFM is a better predictor of the cardiometabolic risk factors and the complications of type 2 diabetes than BMI. Materials and methods: This is a cross sectional study. A list of information was collected from endocrinologists treating type 2 diabetic patients in a primary healthcare clinic and a tertiary hospital in Beirut. This list allowed us to evaluate the micro and macro vascular complications of type 2 diabetic patients, to assess their risk factors and to calculate their RFM and BMI. Results: We analyzed the data of 359 patients. Higher RFM was associated with higher systolic blood pressure (p < 0.05), and both RFM and BMI were significantly correlated to higher CRP, triglyceride levels and liver enzymes. However, the BMI was better associated with other cardiometabolic risk factors such as the total cholesterol (p = 0,003), LDL cholesterol (p = 0,002) and HbA1c (p = 0,01) than RFM. Both RFM and BMI were correlated with higher microalbuminuria (p < 0.001) but unlike BMI, higher RFM was associated with higher creatinine level (p = 0.317 versus 0.047 respectively) and therefore better linked to diabetic nephropathy than BMI. More importantly, we observed an unprecedented result, associating RFM to diabetic neuropathy: a normal RFM excludes diabetic neuropathy with a high probability of 82.5%. Furthermore, a RFM cutoff value of 30.76 in men and 43.31 in women showed an increased risk of developing diabetic neuropathy by 2.464. No association was observed between RFM and diabetic retinopathy. Conclusion: The RFM better predicts microvascular complications of diabetes than BMI except for retinopathy. It is also associated with a worse profile of metabolic syndrome. This study is unique in its discovery of the potential role of RFM as a tool which could rule out neuropathy in diabetic patients.