Agreement Between Bioelectrical Impedance Analysis and Dual-Energy X-ray Absorptiometry to Estimate Fat Mass in Hispanic Adults With Type 2 Diabetes Mellitus: A Cross-Sectional Study

Background: Adipose tissue excess is associated with adverse health outcomes, including type 2 diabetes. Body mass index (BMI) is used to evaluate obesity but is inaccurate as it does not account for muscle mass, bone density, and fat distribution. Accurate measurement of adipose tissue through dual-energy X-ray absorptiometry (DXA) and computed axial tomography (CT) is crucial for managing and monitoring adiposity-related diseases. Still, these are not easily accessible in most hospitals in Mexico. Bioelectrical impedance analysis (BIA) is non-invasive and low-cost but may not be reliable in conditions affecting the body's hydration status, like diabetes. Objectives: To assess fat mass concordance between BIA and DXA in Hispanic-American adults with type 2 diabetes mellitus (T2DM). Methods: Cross-sectional study of a non-probabilistic sample of subjects over 18 years with type 2 diabetes. We used DXA as the reference method.Results: We evaluated the accuracy of FM estimation through BIA and DXA in 309 subjects with type 2 diabetes. Results showed a trend of overestimating the diagnosis of obesity using BIA, especially in individuals with a higher fat mass index (FMI). At the group level, we found BIA accurate; however, at the individual level, it is not. The bias between the 2 methods showed a statistically significant overestimation of body fat by BIA (P <= .01) in both sexes. BIA demonstrated high precision in estimating fat mass. We were able to provide a correction factor of 0.55 kg in men. Conclusion: BIA is inaccurate compared to DXA for body composition assessment in patients with diabetes. Inaccurate measurements can result in misclassification. However, BIA is precise for body composition assessment in patients with diabetes, so it is reliable for tracking patient progress over time.