Glucose effectiveness and its components in relation to body mass index

Abstract

Background Obesity is known to induce a deterioration of insulin sensitivity (SI), one of the insulin‐dependent components of glucose tolerance. However, few studies investigated whether obesity affects also the insulin‐independent component, that is glucose effectiveness (SG). This cross‐sectional study aimed to analyse SG and its components in different body mass index (BMI) categories. Materials and methods Three groups of subjects spanning different BMI (kg m−2) categories underwent a 3‐h frequently sampled intravenous glucose tolerance test: Lean (LE; 18.5 ≤ BMI < 25, n = 73), Overweight (OW; 25 ≤ BMI < 30, n = 90), and Obese (OB; BMI ≥ 30, n = 41). OB has been further divided into two subgroups, namely Obese I (OB‐I; 30 ≤ BMI < 35, n = 27) and Morbidly Obese (OB‐M; BMI ≥ 35, n = 14). Minimal model analysis provided SG and its components at zero (GEZI) and at basal (BIE) insulin. Results Values for SG were 1.98 ± 1.30 × 10−2·min−1 in all subjects grouped and 2.38 ± 1.23, 1.84 ± 0.82, 1.59 ± 0.61 10−2·min−1 in LE, OW and OB, respectively. In all subjects grouped, a significant inverse linear correlation was found between the log‐transformed values of SG and BMI (r = −0.3, P < 0.0001). SG was significantly reduced in OW and OB with respect to LE (P < 0.001) but no significant difference was detected between OB and OW (P = 0.35) and between OB‐I and OB‐M (P = 0.25). Similar results were found for GEZI. BIE was not significantly different among NW, OW and OB (P = 0.11) and between OB‐I and OB‐M (P ≥ 0.07). Conclusions SG and its major component GEZI deteriorate in overweight individuals compared to those in the normal BMI range, without further deterioration when BMI increases above 30 kg m−2.

An Analysis of Glucose Effectiveness in Subjects With or Without Type 2 Diabetes via Hierarchical Modeling

“…Morettini et al. ( 13 ) did, however, find a weak but statistically significant relation between GEZI and BMI based on a MM analysis of 204 healthy subjects. While we also noted a negative correlation between GEZI and BMI, this was not found to be statistically significant in our study.…”

“…More recently, Morettini et al. ( 13 ) analyzed results from a collection of previous studies in subjects with normal glucose tolerance, focusing on factors associated with differences in glucose effectiveness including body mass index. To explore pathogenic factors in type 2 diabetes, Taniguchi et al.…”

“…( 12 ), Morettini et al. ( 13 )], or included only a small number of subjects with T2D [e.g., Taniguchi et al. ( 14 ) and Welch et al.…”

Glucose Effectiveness from Short Insulin-Modified IVGTT and Its Application to the Study of Women with Previous Gestational Diabetes Mellitus

“…All participants underwent a 3-hour IM-IVGTT, with an intravenous insulin infusion (0.03 to 0.05 U/kg) at 20 minutes after the glucose infusion (0.3 g/kg). Blood samples were collected during the 3-hour period, with frequent sampling during the first 30 minutes (typically at time 0, 3, 4, 5,6,8,10,14,19,22,27,30,35,40, 50, 70, 100, 140, 180 minutes), for the measurement of glucose and insulin concentrations. In some cases, blood samples were collected with a slightly different sampling protocol, resulting in the replacement of some of the reported samples with additional samples (e.g., at time 2, 12, 15, 20, 25, 60, 80 minutes).…”

“…The role of glucose effectiveness in predicting possible future derangements of glucose tolerance has gained increasing interest in the last years and the available evidence has been recently reviewed by Alford et al [4], concluding that a lower glucose effectiveness over time is a critical determinant of future glucose intolerance and type 2 diabetes mellitus (T2DM) in subjects at increased risk. Recent evidence has also shown that overweight and obese subjects, who are at recognized increased risk of developing T2DM, exhibit lower glucose effectiveness [5]. On this basis, specific therapies aimed at enhancing glucose effectiveness in at-risk or intolerant subjects may play an important role in preventing T2DM [4].…”