TY - JOUR
T1 - An objective short sleep insomnia disorder subtype is associated with reduced brain metabolite concentrations in vivo
T2 - a preliminary magnetic resonance spectroscopy assessment
AU - Miller, Christopher B.
AU - Rae, Caroline D.
AU - Green, Michael A.
AU - Yee, Brendon J.
AU - Gordon, Christopher J.
AU - D'Rozario, Angela L.
AU - Kyle, Simon D.
AU - Espie, Colin A.
AU - Grunstein, Ronald R.
AU - Bartlett, Delwyn J.
PY - 2017/11
Y1 - 2017/11
N2 - Objectives: To evaluate brain metabolites in objective insomnia subtypes defined from polysomnography (PSG): Insomnia with short sleep duration (I-SSD) and insomnia with normal sleep duration (I-NSD), relative to good sleeping controls (GSCs). Methods: PSG empirically grouped insomnia patients into I-SSD (n = 12: Mean [SD] total sleep time [TST] = 294.7 minutes [30.5]) or I-NSD (n = 19: TST = 394.4 minutes [34.9]). 1H magnetic resonance spectroscopy (MRS) acquired in the left occipital cortex (LOCC), left prefrontal cortex, and anterior cingulate cortex was used to determine levels of creatine, aspartate, glutamate, and glutamine (referenced to water). Glutathione, glycerophosphocholine, lactate, myoinositol, and N-acetylaspartate measurements were also obtained. Sixteen GSCs were included for comparison. Multivariate analysis of variance was used to evaluate differences in creatine, aspartate, glutamate, and glutamine. Results: Aspartate and glutamine concentrations were reduced in the LOCC in I-SSD compared with I-NSD (both p < .05, d = .80-.99). Creatine displayed a nonsignificant mean reduction in I-SSD compared with I-NSD (p = .05, d = .58). Glutamine was reduced in I-SSD compared with controls (p < .05, d = .93). There were no differences in metabolites between all (I-SSD and I-NSD) insomnia patients and controls. In patients with insomnia, LOCC glutamine concentrations were found to be positively correlated with TST (r = .43, p < .05) and negatively correlated with wake-time after sleep onset (r = -.40, p < .05). Conclusions: Results indicate that I-SSD is associated with reduced brain metabolites in the LOCC compared with I-NSD and control concentrations of aspartate, glutamine, and creatine.
AB - Objectives: To evaluate brain metabolites in objective insomnia subtypes defined from polysomnography (PSG): Insomnia with short sleep duration (I-SSD) and insomnia with normal sleep duration (I-NSD), relative to good sleeping controls (GSCs). Methods: PSG empirically grouped insomnia patients into I-SSD (n = 12: Mean [SD] total sleep time [TST] = 294.7 minutes [30.5]) or I-NSD (n = 19: TST = 394.4 minutes [34.9]). 1H magnetic resonance spectroscopy (MRS) acquired in the left occipital cortex (LOCC), left prefrontal cortex, and anterior cingulate cortex was used to determine levels of creatine, aspartate, glutamate, and glutamine (referenced to water). Glutathione, glycerophosphocholine, lactate, myoinositol, and N-acetylaspartate measurements were also obtained. Sixteen GSCs were included for comparison. Multivariate analysis of variance was used to evaluate differences in creatine, aspartate, glutamate, and glutamine. Results: Aspartate and glutamine concentrations were reduced in the LOCC in I-SSD compared with I-NSD (both p < .05, d = .80-.99). Creatine displayed a nonsignificant mean reduction in I-SSD compared with I-NSD (p = .05, d = .58). Glutamine was reduced in I-SSD compared with controls (p < .05, d = .93). There were no differences in metabolites between all (I-SSD and I-NSD) insomnia patients and controls. In patients with insomnia, LOCC glutamine concentrations were found to be positively correlated with TST (r = .43, p < .05) and negatively correlated with wake-time after sleep onset (r = -.40, p < .05). Conclusions: Results indicate that I-SSD is associated with reduced brain metabolites in the LOCC compared with I-NSD and control concentrations of aspartate, glutamine, and creatine.
KW - brain imaging and phenotyping
KW - insomnia
KW - magnetic resonance spectroscopy
KW - sleep and the brain
UR - http://www.scopus.com/inward/record.url?scp=85044543142&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/nhmrc/571421
UR - http://purl.org/au-research/grants/nhmrc/1060992
U2 - 10.1093/sleep/zsx148
DO - 10.1093/sleep/zsx148
M3 - Article
C2 - 28958033
SN - 0161-8105
VL - 40
SP - 1
EP - 11
JO - Sleep
JF - Sleep
IS - 11
M1 - zsx148
ER -