Arterial Stiffness and HbA1c: Association Mediated by Insulin Resistance in Hispanic Adults

Arterial stiffness may be associated with glucose metabolism parameters, such as HbA1c, mainly via insulin resistance. We aimed to investigate the association between arterial stiffness and HbA1c and explore the mediator effect of insulin resistance. In this cross-sectional study, arterial stiffness (pulse-wave velocity; PWV), HbA1c, and insulin resistance (METS-IR) were determined in Hispanic adults. In addition to sex and age, various biochemical measurements (glucose, lipid profile, etc.) and adipose tissue (fat mass and visceral fat mass) were considered as potential confounding variables. A multivariate regression analysis shows that HbA1c is associated with PWV, even after adjusting for several confounding variables. Importantly, the results show that insulin resistance mediated 17.9% of the effect of HbA1c over PWV. In conclusion, HbA1c may be a potential resource for predicting arterial stiffness due to the influence of insulin resistance in Hispanic subjects.

[Índices para la evaluación de la resistencia a la insulina en individuos mexicanos sin diabetes]

Objective

To evaluate the correlation between subrogate index for the evaluation of insulin resistance with the M value obtained with the euglycemic-hyperinsulinemic clamp as well as their sensitivity, specificity, and positive and negative predictive values.

Method

The euglycemic-hyperinsulinemic clamp was performed in subjects having both normal fasting glucose and glycated hemoglobin concentrations. HOMA-IR, QUICKI, HOMA2%S, TyG, TyG*body mass index (BMI) and triglyceride/HDL indexes were calculated. Correlations coefficients were estimated between indexes results and the M-value adjusted by fat-free mass. Areas under the ROC curve were constructed to evaluate overall performance, sensitivity, specificity and predictive values of the subrogate indexes.

Results

57 subjects, 68.4% women, with a mean age of 32.9 ± 11 years-old were included. The subrogate index with the best correlation with the M value was HOMA2%S (r = 0.428), HOMA-IR had the greatest area under the ROC curve (0.683; 95 % confidence interval: 0.503-0.864) and TyG*BMI the best sensitivity (98.2 %) and specificity (51.1 %).

Conclusions

The surrogated indexes for the evaluation of insulin resistance show a significant correlation with the M value obtained with the gold standard. Additional studies are required to determine cut-off values in Mexican population.

Empowerment of patients with type 2 diabetes: current perspectives

Patient empowerment is a continuous process in which knowledge, motivation, and capacity to take control of their disease are built within a person. This concept is not always well understood and applied. This review describes the strategies to induce empowerment in patients with diabetes. In addition, the most common scales used to evaluate empowerment in diabetes is described. Furthermore, the effectiveness of the empowerment-based interventions for improving metabolic control and diabetes knowledge are described. Finally, we discuss opportunities for empowerment implementation in clinical practice and current needs on research that can be translated into public policies.

Mexican Carriers of the HNF1A p.E508K Variant Do Not Experience an Enhanced Response to Sulfonylureas

OBJECTIVE

To assess whether an ethnic-specific variant (p.E508K) in the maturity-onset diabetes of the young (MODY) gene hepatocyte nuclear factor-1α (HNF1A) found in Mexicans is associated with higher sensitivity to sulfonylureas, as documented in patients with MODY3.

RESEARCH DESIGN AND METHODS

We recruited 96 participants (46 variant carriers and 50 age- and sex-matched noncarriers). Response to glipizide (one 2.5-5.0-mg dose), metformin (four 500-mg doses), and an oral glucose challenge was evaluated using a previously validated protocol. Glucose and insulin levels and their areas under the curve (AUCs) were compared between groups.

RESULTS

Carriers of the p.E508K variant had a lower maximum insulin peak during the glipizide challenge as compared with noncarriers with diabetes (P < 0.05). Also, carriers had a lower insulin response after the oral glucose challenge. Following an oral glucose tolerance test in the presence of metformin, carriers of the p.E508K variant with diabetes had a lower maximum insulin peak and total and incremental insulin AUC value as compared with noncarriers with diabetes (P < 0.05). A similar but nonsignificant trend was seen in participants without type 2 diabetes.

CONCLUSIONS

Carriers of variant p.E508K in HNF1A have a reduced insulin response rather than the increased sensitivity to sulfonylureas seen in patients with MODY3.

Non-Nutritive Sweeteners: Evidence on their Association with Metabolic Diseases and Potential Effects on Glucose Metabolism and Appetite

There is ongoing debate concerning non-nutritive sweeteners, their usage, and their effects on metabolism. The association between non-nutritive sweeteners consumption, development of metabolic diseases, and changes in appetite-regulating hormones is not clear. The aim of this article is to present an overview of non-nutritive sweeteners and to examine the scientific evidence of their effects on glucose metabolism and appetite-regulating hormones. Some observational studies suggest an association between non-nutritive sweeteners consumption and development of metabolic diseases; however, adiposity is a confounder frequently found in these studies. Results of the available clinical trials are heterogeneous and not comparable because of major differences between them. Future controlled studies evaluating specific non-nutritive sweeteners, with an appropriate sample size, including a uniform study group, with sufficient exposure time, and considering adjustment for confounder variables, such as anthropometric characteristics, previous consumption of non-nutritive sweeteners, and coexistence of significant metabolic comorbidities, are needed.