Related Experiment Video
Updated: Jun 13, 2026
07:35
Hyperglycemic Clamp and Hypoglycemic Clamp in Conscious Mice
Published on: January 26, 2024
A cardiologist's view of hypoglycemia
Shailesh Nandish1, Jamison Wyatt, Rene Oliveros
1Cardiovascular Diseases, UT Health Science Center, San Antonio, TX, 78229-3900, USA. nandish@uthscsa.edu
Current Atherosclerosis Reports
|April 29, 2010
Summary
Intensive diabetes treatment aiming for low glycated hemoglobin (A1c) did not improve cardiovascular outcomes, likely due to hypoglycemia. Review covers glucose metabolism, hypoglycemia risks, and diabetes drug impacts.
Area of Science:
- Endocrinology
- Cardiology
- Metabolic Research
Background:
- Intensive glycemic control (glycated hemoglobin [A1c] < 7.0%) has not demonstrated improved cardiovascular mortality in recent trials.
- Hypoglycemia, or low blood sugar, is a significant concern with aggressive glucose-lowering therapies.
- The failure to observe cardiovascular benefits may be linked to the adverse effects of frequent hypoglycemic episodes.
Purpose of the Study:
- To review the physiological basis of glucose metabolism.
- To examine the cardiovascular pathophysiology associated with hypoglycemia.
- To analyze clinical trials investigating intensive glucose-lowering strategies and their impact on microvascular and macrovascular complications.
Main Methods:
- Literature review of physiological mechanisms.
- Analysis of cardiovascular consequences of hypoglycemia.
- Examination of data from clinical trials on intensive diabetes management.
- Review of current non-insulin antidiabetic medications.
Main Results:
- Intensive glycemic control did not reduce cardiovascular mortality.
- Excessive hypoglycemia is implicated as a major factor limiting cardiovascular benefits.
- The review synthesizes information on glucose metabolism, hypoglycemia's cardiovascular effects, and trial outcomes.
Conclusions:
- Aggressive targets for glycated hemoglobin (A1c) may not confer cardiovascular benefits due to hypoglycemia risks.
- Understanding the interplay between glucose control, hypoglycemia, and cardiovascular health is crucial.
- Evaluation of non-insulin diabetes drugs should consider their hypoglycemic and cardiovascular profiles.
Related Concept Videos
01:26Hypoglycemia
Hypoglycemia is a blood glucose level below 70 mg/dL. It commonly occurs in individuals using insulin or insulin-secreting drugs, but may also arise in non-diabetic conditions. People with type 1 diabetes are at the highest risk because they depend on exogenous insulin. People with type 2 diabetes are also at risk, especially when treated with insulin or medications such as sulfonylureas, which increase insulin release regardless of blood glucose levels. It develops when insulin levels exceed...
01:15Hypoglycemia and Glucagon
Without prolonged fasting, healthy individuals maintain blood glucose levels above 3.5 mM due to a well-adapted neuroendocrine counterregulatory system that effectively prevents acute hypoglycemia, a potentially life-threatening condition. The primary clinical scenarios for hypoglycemia encompass diabetes treatment, inappropriate production of endogenous insulin or insulin-like substances by tumors, and the use of glucose-lowering agents in non-diabetic individuals. Notably, hypoglycemia in the...
01:29Hyperglycemia
Hyperglycemia is an abnormally high blood glucose level. It is diagnosed by fasting glucose ≥126 mg/dL, 2-hour oral glucose tolerance test (or OGTT) ≥200 mg/dL, random glucose ≥200 mg/dL with symptoms, or HbA1c ≥6.5%. However, HbA1c results may be unreliable in certain conditions, such as anemia or hemoglobinopathies, and the diagnosis should be confirmed unless classic symptoms are present. Postprandial hyperglycemia is typically considered significant when glucose levels exceed 180 mg/dL two...
01:19Overview of Carbohydrate Metabolism
Carbohydrate metabolism is a fundamental biochemical process that ensures a constant supply of energy to living cells. The most important carbohydrate is glucose, which can be broken down via glycolysis to enter into the Krebs cycle and eventually lead to the production of ATP through oxidative phosphorylation.
Glucose transport into cells is facilitated by a family of transport proteins called GLUT (Glucose Transporters). GLUT4 is the primary glucose transporter for insulin-stimulated glucose...
Glucose transport into cells is facilitated by a family of transport proteins called GLUT (Glucose Transporters). GLUT4 is the primary glucose transporter for insulin-stimulated glucose...
01:22Diabetes Mellitus: Type 2 and Gestational
Type 2 diabetes, characterized by insulin resistance, arises when the insulin receptors on cells lose responsiveness to insulin, diminishing the cell's capacity to take up glucose, resulting in elevated blood glucose levels. To receive a diagnosis of Type 2 diabetes, a series of blood glucose tests are necessary to assess whether the blood glucose falls within normal parameters. If the result is out of the normal range, a patient may be diagnosed as prediabetic or diabetic, depending on the...
01:15Diabetes: Symptoms, Diagnosis, and Complications
For most patients, experiencing several weeks of polyuria, polydipsia, fatigue, and significant weight loss may indicate the presence of diabetes. Furthermore, adults displaying the phenotypic appearance of type 2 diabetes (particularly those who are obese and not initially insulin-requiring), may have islet cell autoantibodies, suggesting autoimmune-mediated β cell destruction and a diagnosis of latent autoimmune diabetes of adults (LADA). The categorization of glucose homeostasis is based on...