Glucose Metabolism in Identical Twins Discordant for Obesity. The Critical Role of Visceral Fat¹

Abstract

Obesity, especially intraabdominally deposited fatness, is associated with reduced insulin sensitivity. However, it is not well established whether this association is confounded by genetic factors. We studied 23 monozygous twin pairs (14 female, 9 male), 33-59 yr old, who had, on the average, 18 kg intrapair difference in body weight. A 75-g oral glucose tolerance test with glucose and insulin measurements at 30-min intervals was performed, and fat distribution was determined with magnetic resonance imaging. The pairs were divided into two groups by the gender-specific median of the abdominal visceral fat area (AVF) in the obese co-twins. In the high-AVF pairs, the mean area under curve (AUC) for glucose (mmol x min/L) was 758 vs. 968 (P = 0.001), AUC for insulin (mU x min/L) was 4320 vs. 8741 (P = 0.001), and insulin sensitivity index (mg x L x L/mmol x mU x min) was 71.5 vs. 45.9 (P < 0.001) in the lean and obese co-twins, respectively. In the low AVF pairs, the mean AUC for glucose was 669 vs. 706 (not significant), AUC for insulin was 3323 vs. 4241 (not significant), and the sensitivity index was 85.2 vs. 73.7 (P = 0.04) in the lean and obese co-twins, respectively. In subjects who are genetically identical but who are discordant for body mass, only those who differ most in visceral fat level are characterized by major alterations in insulin sensitivity and glucose tolerance.

Actigraph Calibration in Obese/Overweight and Type 2 Diabetes Mellitus Middle-Aged to Old Adult Patients

“…Regular PA is a fundamental part of lifestyle behavior in treating DM2, 2 and on the primary prevention of this disease. 1,3,4 There are several benefits of regular PA in individuals with DM2: it reduces the risk of cardiovascular disease, 5 glycated hemoglobin A1c, 2 blood pressure, 3,6 and total abdominal fat; 7 it also improves insulin sensitivity, 7 glycemic control, 6,8 and increases the muscle mass. 9 Regular moderate-intensity PA can be used to improve metabolic risk variables such as insulin and leptin in overweight/obese postmenopausal women.…”

Insulin resistance in people living with HIV is associated with exposure to thymidine analogues and/or didanosine and prior immunodeficiency

“…These are all well-described risk factors for both insulin resistance and T2DM [ 6 ]. Especially, abdominal obesity, including increased amounts of visceral fat, is thought to be associated with a high risk of developing insulin resistance [ 7 , 8 ].…”

“…Insulin resistance is a key determinant of T2DM and has previously been associated with age, overweight, and obesity [ 6 ]. Especially, abdominal obesity is thought to be associated with a high risk of developing insulin resistance [ 7 , 8 ]. In PLWH, exposure to older generation antiretroviral therapy (ART) has been associated with both the development of T2DM and long-lasting alterations of body fat from subcutaneous adipose tissue to visceral adipose tissue [ 9 – 12 ].…”

Mental, physical, and social well-being and quality of life in healthy young adult twin pairs discordant and concordant for body mass index

“…All twin pairs were same-sex pairs. The BMI discordance cut-off point was determined in earlier studies [25,26]. The pairs were identified from 2 population-based longitudinal studies of 10 complete Finnish birth cohorts, FinnTwin16 (years 1975-1979, n = 2578 pairs) and FinnTwin12 (years 1983-1987, n = 2839 pairs), with data retrieved between 2003 and 2013 [27].…”