Abstract | STUDY OBJECTIVES:
Primary insomnia (PI) is a sleep disorder characterized by difficulty with sleep initiation, maintenance, and/or the experience of nonrestorative sleep combined with a subsequent impairment of daytime functioning. The hyperarousal hypothesis has emerged as the leading candidate to explain insomnia symptoms in the absence of specific mental, physical, or substance-related causes. We hypothesized that the cellular energetic metabolites, including beta nucleoside triphosphate, which in magnetic resonance spectroscopy approximates adenosine triphosphate ( ATP), and phosphocreatine (PCr), would show changes in PI reflecting increased energy demand. DESIGN AND SETTING: Matched-groups, cross-sectional study performed at two university-based hospitals. PATIENTS: Sixteen medication-free individuals (eight males, eight females; mean ± standard deviation (SD) age = 37.2 ± 8.4 y) with PI and 16 good sleepers (nine males, seven females; mean ± SD age = 37.6 ± 4.7 y). MEASUREMENTS: Diagnosis was established for all individuals by unstructured clinical interview, Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID), sleep diary, and actigraphy. Polysomnography was collected in individuals with PI. Phosphorous magnetic resonance spectroscopy (31P MRS) data were collected on all individuals at 4 Tesla. We assessed cell membrane (anabolic precursors and catabolic metabolites) and bioenergetic ( ATP, phosphocreatine) metabolites in gray matter and white matter to determine their relationship to the presence and severity of PI. RESULTS: CONCLUSIONS: These results support the hyperarousal hypothesis in PI based on lower phosphocreatine in gray matter in the PI group.
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Authors | David G Harper, David T Plante, J Eric Jensen, Caitlin Ravichandran, Orfeu M Buxton, Kathleen L Benson, Shawn P O'Connor, Perry F Renshaw, John W Winkelman |
Journal | Sleep
(Sleep)
Vol. 36
Issue 4
Pg. 493-500
(Apr 01 2013)
ISSN: 1550-9109 [Electronic] United States |
PMID | 23564996
(Publication Type: Journal Article, Multicenter Study)
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Chemical References |
- Biomarkers
- Phosphorus Isotopes
- Phosphocreatine
- Adenosine Triphosphate
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Topics |
- Adenosine Triphosphate
(metabolism)
- Adult
- Biomarkers
(metabolism)
- Brain
(metabolism)
- Cell Membrane
(metabolism)
- Cross-Sectional Studies
- Energy Metabolism
- Female
- Humans
- Magnetic Resonance Spectroscopy
(methods)
- Male
- Phosphocreatine
(metabolism)
- Phosphorus Isotopes
- Polysomnography
(methods)
- Sleep Initiation and Maintenance Disorders
(metabolism)
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