Correlation Between Anthropometric Parameters And Abdominal Fat Area Assessed By A Computed Tomography Method, And Relationship Of The Fat Distribution With Metabolic Disorders In Chinese Type 2 Diabetic Male Patients

[Objective] To investigate the relationship of simple anthropometric parameters with abdominal subcutaneous adipose area (SA) and visceral adipose area (VA) in Chinese type 2 diabetic male patients, and to generate equations predicting SA and VA by simple anthropometric parameters; To evaluate the best cut-off point, sensitivity and specificity of simple anthropometric parameters [body index (BMI), waist circumference (WC) and Waist-to-hip ratio (WHR)] in predicting of abdominal visceral obesity in Chinese type 2 diabetic male patients; To investigate the characteristics of body fat distribution and relationship of it with the clinical metabolic parameters in Chinese type 2 diabetic male patients.[Materials and Methods] Observational, cross sectional study.â‘ The total body fat mass was measured using BMI, VA and SA were determined using a computed tomography (CT) scans made at the level of L4/L5 in 91 Chinese type 2 diabetic male patients, VSR is the ratio of the VA to SA and the total abdominal fat area (TAF) was calculated by SFA plus VFA. Blood pressure (BP), fasting serum lipids such as triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL-c), apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB100), fast plasma glucose (FPG), hemoglobin A_1c (HbA_1c), fast serum insulin (Fins), fast plasma free fatty acid (FFA0h), postprandial 2 hour plasma free fatty acid (FFA2h) and serum uric acid (UA) were also determined.â‘¡Multiple stepwise regression analysis was used to generate equations for predicting SA and VA from simple anthropometric parameters of 77 subjects (80%) randomly selected from the overall sample. These equations were then cross-validated in the remaining 14 subjects (20%).Receiver operating characteristic (ROC) curves was used as index for analysis.â‘£The relationship between the metabolic risk factors and BMI, VA, SA, TAF and VSR in Chinese type 2 diabetic male patients was made by Pearson correlation analyses, partial correlation analyses and Stepwise multiple regression analysis.[Results]â‘ Age had no relation with the body fat distribution; The VSR was significantly higher in Chinese type 2 diabetic male patients than in obese Chinese and in obese European and Americans; VA was significantly positively correlated with simple anthropometric parameters (BMI, WC and WHR, r=0.682, 0.676, 0.410, respectively; p=0.000 ), in which BMI and WC were the better than WHR; 89.80% of over-weight/obesity and 47.62% of normal weight patients were abdominal visceral fat obesity (VFO) (VA≥100 cm²) by CT diagnosis.â‘¡The best regression equations were developed for predicting SA and VA, and the explanatory variables included BMI and WC. The equation for predicting SA included only BMI; the equation for predicting VA included WC and BMI. In the cross-validation study, the differences between predicted and observed values of VA and SA were+2.06% and +4.34%, respectively. The goodness of fit between predicted and observed values is good.â‘¢The best cut-off points of these anthropometric parameters in assessing VFO were as follow: BMI: 25 kg/m², WC: 90 cm, WHR: 0.93. Among them WC showed most sensitive and specific. 100% and 91.90% of type 2 diabetic male patients appeared VFO in patients with BMI≥28 kg/m² or WC≥95cm.â‘£HbA_1c, TG and FFA0h were higher in patients with VFO than in those with subcutaneous fat obesity (SFO), Fins and FPG were lower in patients with VFO than in those with SFO, P＜0.05. Pearson correlation analyses showed that age and diabetes duration were all positively correlated with SBP, HDL-c, and negatively correlated with TG; BMI was positively correlated with SBP, DBP, Fins, FFA0h, TG and UA, and inversely correlated with HDL-c. TAF, SA and VA were all negatively correlated with FPG and HDL-c, and positively correlated with Fins, FFA0h and TG; TAF and VA were also positively correlated with UA, FFA2h, SBP, DBP; SA was negatively correlated with HbA_1c, VSR was positively correlated with HbA_1c. Adjusting for age and diabetes duration, partial correlation analyses showed that BMI was still positively correlated with SBP, DBP, Fins, UA, FFA0h and TG, and negatively correlated with HDL-c and FPG; TAF, SA and VA were negatively correlated with FPG and HDL-c, and positively correlated with Fins, FFA0h, FFA2h and TG; Adjusting for age, diabetes duration and BMI, partial correlation analyses showed that TAF, SA and VA were all only positively correlated with FFA0h, VSR was solely positively correlated with HbA_1c, but other relationships did not persisted.⑤Stepwise multiple regression analysis showed that BMI was an independent predictor for DBP, UA and Fins (adjusting R²=0.091, 0.117, 0.203,p=0.004, 0.001, 0.000, respectively), and was an important predictor for SBP, TG and HDL-c (adjusting R²=0.222, 0.236, 0.166, p=0.000, 0.002, 0.022, respectively, p=0.000); TAF was an independent predictor for FFA2h (adjusting R²=0.056, p=0.021); VA was an independent variable associated with FFA0h (adjusting R²=0.215, p=0.000); SA was an independent predictor for FPG (adjusting R²=0.096, p=0.004); VSR was an independent predictor for HbA_1c (adjusting R²=0.053, p=0.020).[Conclusion]â‘ Similarly with obese Chinese, Our data suggest that in Chinese type 2 diabetic male patients, the body fat distribution was characterized with central obesity.â‘¡The absolute amount of human VA and SA in Chinese type 2 diabetic male patients can be predicted from anthropometric measurements.â‘¢Simple anthropometric parameters (BMI, WC, WHR) can all predict VFO in Chinese type 2 diabetic male patients, in which BMI was the better than WHR and WC.â‘£The total body fat mass (BMI), TAF and VA play more important role than SA in the metabolic disorders.