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Functional hypoglycemia: facts and fancies
Canadian Family Physician Medecin De Famille Canadien
|February 1, 2011
Summary
Functional hypoglycemia symptoms may appear when blood glucose is low. Diagnosis requires confirmed low glucose and symptom relief with glucose, as tests can be misleading, leading to overdiagnosis.
Area of Science:
- Endocrinology
- Metabolic Disorders
Background:
- Reactive or functional hypoglycemia is proposed when symptoms of cerebral dysfunction or adrenergic hyperactivity occur postprandially with low blood glucose.
- Symptoms are nonspecific and require concurrent low blood glucose levels and rapid symptom relief upon glucose ingestion for diagnosis.
Purpose of the Study:
- To clarify diagnostic criteria for functional hypoglycemia.
- To address the overdiagnosis of functional hypoglycemia and the syndrome of non-hypoglycemia.
Main Methods:
- Review of diagnostic criteria for functional hypoglycemia.
- Analysis of the oral glucose tolerance test (OGTT) in evaluating patients with suspected hypoglycemia.
Main Results:
- The oral glucose tolerance test (OGTT) can yield misleading results, with many normal individuals exhibiting glucose values below the 'normal' range.
- Overdiagnosis of functional hypoglycemia may be attributed to the unreliability of diagnostic tests and the 'syndrome of non-hypoglycemia' where symptoms are misattributed.
Conclusions:
- Functional hypoglycemia is a real condition that can be effectively managed.
- Accurate diagnosis requires careful correlation of symptoms with objective low blood glucose measurements and prompt symptom resolution after glucose intake.
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