title: Frontal brain lobe impairment in obstructive sleep apnoea: a proton MR spectroscopy study.
abstract: Patients with obstructive sleep apnoea syndrome frequently have cognitive deficits, especially related to executive functions, which cannot be fully explained by daytime sleepiness and are partial irreversible after nasal continuous positive airway pressure treatment. The causal mechanism of these cognitive deficits is not yet known, but it has been proposed that they are associated with chemical and structural brain cell injury. The aim of this study was to investigate brain metabolism in patients with sleep apnoea syndrome. Twenty-two patients with severe sleep apnoea and 10 healthy volunteers of comparable age were studied using single voxel proton magnetic resonance spectroscopy. Magnetic resonance spectra were obtained from prefrontal cortex, parieto-occipital and frontal periventricular white matter. N-acetylaspartate-to-creatine and choline-to-creatine ratios were significantly lower in the frontal white matter of obstructive sleep apnoea patients when compared to controls. Absolute concentrations of N-acetylaspartate and choline were also significantly reduced in the frontal white matter of patients with sleep apnoea. Frontal lobe white matter lesions are known to be associated with cognitive executive dysfunction. The findings of this study may offer an explanation for the sometimes irreversible cognitive deficits associated with sleep apnoea.
authors.affiliation: Sleep Laboratory, Pulmonary Dept, University of Athens Medical School, 10, Bakopoulou Str., 154 51 Athens, Greece. annakara@otenet.gr.
authors.forename: M
authors.initials: M
authors.lastname: Alchanatis
authors.forename: N
authors.initials: N
authors.lastname: Deligiorgis
authors.forename: N
authors.initials: N
authors.lastname: Zias
authors.forename: A
authors.initials: A
authors.lastname: Amfilochiou
authors.forename: E
authors.initials: E
authors.lastname: Gotsis
authors.forename: A
authors.initials: A
authors.lastname: Karakatsani
authors.forename: A
authors.initials: A
authors.lastname: Papadimitriou
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D006801:Humans; D007294:Inositol / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011522:Protons; D020181:Sleep Apnea, Obstructive / Q000473:pathology*; D018709:Statistics, Nonparametric
chemical_list: D011522:Protons; D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline