The Effects of Obstructive Sleep Apnea Syndrome on the Dentate Gyrus and Learning and Memory in Children.
Obstructive sleep apnea syndrome (OSAS) is associated with intermittent hypoxia and sleep loss. In children, impairments of cognitive function are important manifestations, but the underlying pathology is unknown. We hypothesized that OSAS would affect the dentate gyrus, a hippocampal subdivision essential to neurogenesis and cognition, and that this impact would further affect cognitive function in children. In children with OSAS (n= 11) and control subjects (n= 12; age and sex matched), we performed diffusion tensor imaging and structural MRI, polysomnography, and neuropsychological assessments. We found that OSAS was associated with decreased mean diffusivity of the left dentate gyrus (p= 0.002; false discovery rate corrected; adjusting for sex, age, and body mass index), showing a large effect size (partial η2= 0.491), but not with any other structural measures across the brain. Decreased dentate gyrus mean diffusivity correlated with a higher apnea hypopnea index (Spearman'sr= -0.50,p= 0.008) and a greater arousal index (r= -0.44,p= 0.017). OSAS did not significantly affect neuropsychological measures (pvalues >0.5); however, a lower verbal learning score correlated with lower dentate gyrus mean diffusivity (r= 0.54,p= 0.004). Path analysis demonstrated that dentate gyrus mean diffusivity mediates the impact of OSAS on verbal learning capacity. Finally, the diagnostic accuracy of a regression model based on dentate gyrus mean diffusivity reached 85.8% (cross validated). This study demonstrates a likely pathway of effects of OSAS on neurocognitive function in children, as well as potential utility of the dentate gyrus mean diffusivity as an early marker of brain pathology in children with OSAS.SIGNIFICANCE STATEMENTIn this study we investigate the relationships between dentate gyrus structure, hippocampus-dependent cognition, and obstructive sleep apnea syndrome (OSAS). We demonstrate lower mean diffusivity of the dentate gyrus in children with OSAS, which correlates with a lower verbal learning and memory score. This study provides new evidence of disrupted microstructure of the dentate gyrus in children with OSAS that may help explain some of the neurocognitive deficits described in these children.
Division of Child and Adolescent Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, New York 10032, and.
Jiook
0000-0002-5314-7992
J
Cha
Division of Respiratory and Sleep Medicine, Children's Hospital at Montefiore.
Johanna A
JA
Zea-Hernandez
Division of Respiratory and Sleep Medicine, Children's Hospital at Montefiore.
Sanghun
S
Sin
Division of Respiratory and Sleep Medicine, Children's Hospital at Montefiore.
Katharina
K
Graw-Panzer
Departments of Radiology.
Keivan
K
Shifteh
Epidemiology and Population Health, and.
Carmen R
CR
Isasi
Gruss Magnetic Resonance Research Center, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York 10467.
Mark E
ME
Wagshul
Neurology, and.
Eileen E
EE
Moran
Division of Child and Adolescent Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, New York 10032, and.
Jonathan
J
Posner
Neurology, and.
Molly E
ME
Zimmerman
Division of Respiratory and Sleep Medicine, Children's Hospital at Montefiore, rarens@montefiore.org.
Raanan
R
Arens
D000293:Adolescent; D016022:Case-Control Studies; D018891:Dentate Gyrus / Q000000981:diagnostic imaging / Q000502:physiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D020181:Sleep Apnea, Obstructive / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014706:Verbal Learning
diffusion anisotropy; hippocampus; magnetic resonance imaging