Association of Baseline Characteristics With Insulin Sensitivity and β-Cell Function in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness (GRADE) Study Cohort

Abstract

OBJECTIVE We investigated sex and racial differences in insulin sensitivity, β-cell function, and glycated hemoglobin (HbA1c) and the associations with selected phenotypic characteristics. RESEARCH DESIGN AND METHODS This is a cross-sectional analysis of baseline data from 3,108 GRADE (Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study) participants. All had type 2 diabetes diagnosed <10 years earlier and were on metformin monotherapy. Insulin sensitivity and β-cell function were evaluated using the HOMA of insulin sensitivity and estimates from oral glucose tolerance tests, including the Matsuda Index, insulinogenic index, C-peptide index, and oral disposition index (DI). RESULTS The cohort was 56.6 ± 10 years of age (mean ± SD), 63.8% male, with BMI 34.2 ± 6.7 kg/m2, HbA1c 7.5 ± 0.5%, and type 2 diabetes duration 4.0 ± 2.8 years. Women had higher DI than men but similar insulin sensitivity. DI was the highest in Black/African Americans, followed by American Indians/Alaska Natives, Asians, and Whites in descending order. Compared with Whites, American Indians/Alaska Natives had significantly higher HbA1c, but Black/African Americans and Asians had lower HbA1c. However, when adjusted for glucose levels, Black/African Americans had higher HbA1c than Whites. Insulin sensitivity correlated inversely with BMI, waist-to-hip ratio, triglyceride-to-HDL-cholesterol ratio (TG/HDL-C), and the presence of metabolic syndrome, whereas DI was associated directly with age and inversely with BMI, HbA1c, and TG/HDL-C. CONCLUSIONS In the GRADE cohort, β-cell function differed by sex and race and was associated with the concurrent level of HbA1c. HbA1c also differed among the races, but not by sex. Age, BMI, and TG/HDL-C were associated with multiple measures of β-cell function and insulin sensitivity.

Pseudotime Ordering Single-Cell Transcriptomic of β Cells Pancreatic Islets in Health and Type 2 Diabetes

“…Figure 2E shows the distribution of cells from different donors. The different cell composition of female donor Normal 3 (p < 8.252e-5) might suggest the difference of metabolism signature between males and females, which is confirmed in the existed cohort study (Rasouli et al 2021). The unique cell states of Normal 3 also can be observed in the individual pseudotime analysis (Fig.…”

Exploring the determinants of ethnic differences in insulin clearance between men of Black African and White European ethnicity

“…While low adiponectin concentrations appear to be an important factor, they do not entirely explain the low insulin clearance of the BA men. Low insulin clearance has been demonstrated in a wide variety of BA subjects, including healthy men [27] and women [36], obese adolescents [37] and adults with T2D [38]. The highly conserved nature of this trait is well illustrated by Osei et al who demonstrated that while African-Americans, native Ghanaians and Ghanaian immigrants to the USA have similar rates of insulin clearance to each other, all three BA groups have lower insulin clearance compared with White Americans [39].…”

“…While low adiponectin concentrations appear to be an important factor, they do not entirely explain the low insulin clearance of the BA men. Low insulin clearance has been demonstrated in a wide variety of BA subjects, including healthy men [ 27 ] and women [ 36 ], obese adolescents [ 37 ] and adults with T2D [ 38 ]. The highly conserved nature of this trait is well illustrated by Osei et al .…”

Distance to Health Care Facilities, Lifestyle Risk Factors, and Stage at Diagnosis in relation to Geographic Pattern of Esophageal Cancer in Tanzania, 2006–2016

“…Dietary assessment tools such as food frequency questionnaire, hot food and beverages intake, and nutrient intake would be informative. It is noteworthy that the age-standardized cancer rate is 8.9 per 100,000; that rate in men (11.7) is 1.75 times greater than that in women (6.7 per 100,000) [ 35 ]. This ORCI esophageal cancer database may serve as the basis for such studies in Tanzania.…”