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Updated: May 25, 2026
06:59
Characterization of Metabolic Status in Nonhuman Primates with the Intravenous Glucose Tolerance Test
Published on: November 13, 2016
Glucose tolerance in patients with narcolepsy.
Pierre A Beitinger1, Stephany Fulda, Mira A Dalal
1Max Planck Institute of Psychiatry, Munich, Germany.
Sleep
|February 2, 2012
Summary
Narcolepsy patients show normal glucose metabolism, even with obesity. This suggests narcolepsy itself is not a risk factor for impaired glucose tolerance or diabetes.
Area of Science:
- Endocrinology
- Sleep Medicine
- Metabolic Research
Background:
- Obesity is common in narcolepsy patients.
- Increased non-insulin dependent diabetes occurrence reported in narcolepsy.
- Relationship between narcolepsy, obesity, and glucose metabolism is unclear.
Purpose of the Study:
- To investigate glucose metabolism in narcolepsy patients.
- To determine if narcolepsy impacts glucose tolerance independently of obesity.
Main Methods:
- Case-control study comparing 17 narcolepsy/cataplexy patients to 17 matched healthy controls.
- Performed a 75-g oral glucose tolerance test (OGTT).
- Assessed glucose tolerance, insulin sensitivity, and secretion using OGTT, homeostasis model assessment, and minimal model analysis.
Main Results:
- No significant differences in standard OGTT measures between narcolepsy patients and controls.
- Glucose tolerance, insulin sensitivity, and secretion were comparable between groups when matched for BMI.
Conclusions:
- Narcolepsy patients did not exhibit clinically relevant glucose metabolism abnormalities compared to weight-matched controls.
- Narcolepsy is unlikely to be an independent risk factor for impaired glucose tolerance or diabetes.
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