Background: The relationship between subcutaneous fat area (SFA) and diabetes mellitus (DM) is still not well described due to the fact that SFA has two aspects; it can buffer energy surplus and also reflect obesity severity.
Methods: 3967 subjects, from baseline survey data of the Shanghai Nicheng Cohort Study, were analyzed. Thigh subcutaneous fat area (TSFA), abdominal subcutaneous fat area (ASFA), and visceral fat area (VFA) were measured by magnetic resonance imaging. TSFA% and ASFA% were calculated as the ratio of TSFA and ASFA to the sum of VFA, ASFA, and TSFA, respectively and reflects the propensity to store energy in a given location. Diagnosis of newly diagnosed diabetes mellitus (NDM) as well as assessments of insulin sensitivity (Homeostatic Model Assessment of insulin resistance and ISI0,120 [GUTT]), and β-cell function (early-, first- and second-phase disposition indices) were made based on an oral glucose tolerance test.
Results: Compared to those without DM, TSFA%, ASFA%, and VFA% in men and women with NDM were 0.25 versus 0.21, 0.39 versus 0.38, and 0.36 versus 0.41; and 0.37 versus 0.32, 0.38 versus 0.37, and 0.26 versus 0.31, respectively. Before and after adjustment for potential confounding factors, each 1-SD increase in TSFA% was associated with a 37-47% and a 34-39% decreased likelihood of NDM in Chinese men and women, respectively (both P <0.05). Multivariable linear regression showed that TSFA% was mildly positively associated with all indicators of β-cell function and/or insulin sensitivity in women and mildly positively associated with DI1st in men. The favorable associations of NDM, insulin sensitivity, and β-cell function with TSFA% were stronger than with ASFA%.
Conclusion: TSFA% reflects the propensity to store energy in subcutaneous fat which is associated with a lower risk of NDM and better β-cell function in both genders.
X. Hou: None. P. Chen: None. L. Wei: None. Y. Bao: None. W. Jia: None.