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Hypoglycemia-associated autonomic failure in diabetes
1Department of Medicine, Washington University in St. Louis and Barnes-Jewish Hospital, St. Louis, Missouri, USA.
Handbook of Clinical Neurology
|October 8, 2013
Summary
Hypoglycemia-associated autonomic failure (HAAF) in diabetes leads to recurrent low blood sugar by impairing the body's response and awareness. Addressing HAAF risk factors can improve glycemic control and reduce hypoglycemia incidence.
Area of Science:
- Endocrinology
- Metabolic Disorders
- Diabetes Mellitus Research
Background:
- Hypoglycemia-associated autonomic failure (HAAF) describes impaired counterregulation and awareness of low blood sugar in diabetes.
- This failure, seen in type 1 and advanced type 2 diabetes, creates a cycle of recurrent hypoglycemia.
- Factors like prior hypoglycemia, sleep, or exercise exacerbate HAAF.
Purpose of the Study:
- To explain the pathophysiology of HAAF and its role in recurrent hypoglycemia.
- To identify risk factors for HAAF and hypoglycemia.
- To advocate for hypoglycemia risk reduction strategies in diabetes management.
Main Methods:
- The study reviews the pathophysiology of glucose counterregulation and sympathoadrenal responses during hypoglycemia.
- It examines the mechanisms behind defective epinephrine release and impaired hypoglycemia awareness.
- The concept of HAAF is used to explain increased hypoglycemia incidence in advanced diabetes.
Main Results:
- HAAF impairs both glucose counterregulation (epinephrine response) and hypoglycemia awareness (sympathoadrenal response).
- The underlying pathophysiology is similar in type 1 and advanced type 2 diabetes.
- Hypoglycemia unawareness is reversible with consistent avoidance of low blood sugar.
Conclusions:
- HAAF pathophysiology explains increased hypoglycemia risk as diabetes progresses.
- Individualized glycemic goals are crucial due to mortality risks from hypoglycemia.
- Implementing hypoglycemia risk reduction strategies can improve glycemic control and patient safety.
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