Characteristics of β cell function in different glucose tolerance and the influence of body fat

Abstract

Objective To explore the characteristics of β cell function in different glucose tolerance and the influence of body fat. Methods Cross sectional cluster random sampling investigation of the resident between 20-74 yrs in Urumuqi, north and south of Xinjiang Provience from March 2009 to March 2011. All the subjects used the standard 75 g oral glucose tolerance test (OGTT) and insulin releasing to define their β cell function. Normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT), IFG+IGT and type 2 diabetes mellitus (T2DM) were defined according to the WHO 1999 criteria. Results (1) Compared with NGT group, HOMA-β (130±92, 90±79, 66±55, 68±47, 71±46; t=3.19-4.88, all P<0.01), AUCins/gluc30 (13±9, 12±7, 11±9, 10±7, 8±6; t=2.51-3.24, all P<0.01), AUCins/gluc120 (5.0±4.0, 4.6±4.2, 4.0±3.7, 3.9±2.9, 3.7±2.9; t=2.62-4.46, all P<0.01), DI30 (10.1±5.6, 7.0±4.3, 5.2±3.9, 3.6±3.1, 2.2±2.1; t=2.76-3.64, all P<0.01) and DI120 (3.1±3.0, 2.8±2.1, 1.8±1.5, 1.3±0.9, 1.2±1.0; t=2.71-9.22, all P< 0.01) were significantly decreased in IFG, IGT and T2DM groups. (2) Compared with NGT group, AUCins/gluc120 were increased with the increase of BMI (5.3±2.3, 6.2±2.3, 4.7±2.1, 4.1±2.0; t=-4.48--2.07, all P<0.05) in NGT, IFG, IGT and T2DM groups. (3) Multiple logistic regression analysis indicate that BMI is the related risk factor of HOMA-β (P=0.01) and AUCins/gluc120 (P<0.01). Conclusion With the progression of type 2 diabetes, the β cell function and its compromise with insulin resistance will decreased gradually. Body fat could have some influences on β cell function in different glucose tolerance state. Key words: Diabetes mellitus, type 2; Islet β cell; Impaired glucose; Impaired glucose tolerance