Characteristics of body fat distribution and changes of isletβ-cell function among obese women with different insulin resistance status

AIM To explore the characteristics of body fat distribution and the changes of isletβ-cell function among non-diabetic obese women with different insulin resistance(IR)status.METHODS Dualenergy X-ray absorptiometry(DEXA)was applied to measure the body fat content of 94 obese women whose total body fat content was greater than 35%without exception.Total body,trunk,arm and leg fat content,fat mass in different parts-total fat mass ratio were calculated.Area under the curve of insulin(AUC_(ins)),acute insulin response(AIR),homeostasis model assessment ofβ-cell function index(H0MA2-%β),homeostasis model assessment of insulin sensitivity index(HOMA2-%S)and homeostasis model assessment of insulin resistance index(HOMA2-IR)were calculated by using intravenous glucose tolerance test(IVGTT).The patients were assigned into four groups based on the quartile of HOMA2-IR to compare basic clinical characteristics,isletβ-cell function,body fat content and distribution of each group,and investigate the related factors of HOMA2-IR.The differences of the above mentioned indices in different age were identified. RESULTS With the elevation of HOMA2-IR,the trunk fat content,trunk fat-total fat ratio,HOMA2-%β, AUC_(ins),AIR and 2 hours glucose of glucose tolerance test(2hPG)were increased.In contrast,leg fat-total ratio fat and HOMA2-%S were decreased.HOMA2-IR was positively correlated with trunk fat content,trunk fat-total ratio body fat and 2hPG(r=0.358,0.205,0.225,all P0.05).However,it showed a negative association with age and leg fat-total fat ratio(r=-0.216,-0.313,all P0.05).The obese women who were younger than 30 years old maintained higher total body,trunk fat content and limb fat content(all P0.05),as well as higher HOMA2-%β,HOMA2-IR,AIR,AUC_(ins)relatively and lower HOMA2-%S(all P0.05)when compared with the subjects older than 30 years old.CONCLUSION Among non-diabetic obese women with high insulin resistance status,the accumulation of trunk fat and reduction of leg fat distribution are more likely to occur, and the compensatory of isletβ-cell function can also be identified.