RESUMO
BACKGROUND AND PURPOSE: Obstructive sleep apnea syndrome (OSAS) is a chronic disease ranging from innocuous to life-threatening and causes brain alterations manifested by neuropsychiatric symptoms. Neuron-specific enolase (NSE) and the astrocytic protein S100B are established sensitive peripheral biochemical markers of brain injury. In the present work we measured the serum levels of S100B and NSE in order to evaluate the deleterious effects of OSAS to the brain. PATIENTS AND METHODS: We studied 29 male patients with OSAS and 17 male asymptomatic control subjects with an apnea-hypopnea index (AHI) less than five events per hour. Patients and control subjects were evaluated by full-night polysomnography (PSG) and by Mini International Neuropsychiatric Interview (MINI) for the presence of neuropsychiatric symptoms. In the morning following the PSG, blood was collected and serum levels of S100B and NSE were measured using standard techniques. RESULTS: The AHI in the OSAS group was (mean+/-SD) 27+/-25 AH/h, ranging from 5 to 99 AH/h. S100B was higher in OSAS (0.15+/-0.09 microg/l) than in the control group (0.08+/-0.06 microg/l; P<0.01). Serum NSE was similar in both groups (17.5+/-12.2 vs. 15.8+/-6.8ng/ml). CONCLUSIONS: We report elevated serum S100B levels in OSAS patients in this study.