The Correlative Study Of Cognitive Impairment And Serum S100β,NSE,EPO Levels In Patients With Obstructive Sleep Apnea And Hypopnea Syndrome

Objective To explore the possible mechanism of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome(OSAHS) by detecting the cognitive dysfunction, nocturnal hypoxemia, sleep disorders, serum EPO, NSE, S100β levels and analyzing the relationship among them.Methods Overnight polysomnography(PSG) was performed to a total of 98 patients with snoring complaint in our electrophysiological sleep center. Based on the results of the apnea-hypopnea index(AHI) assessment, these patients were divided into four groups: primary snoring group(AHI<5/h, n=30), mild(AHI 5-15/h, n=15),moderate(AHI 15-30/h, n=14) and severe(AHI≥30/h, n=39) OSAHS groups. The sleep breathing situation including the lowest oxygen saturation(LSa O2), apnea hypopnea index(AHI), total sleep time(TST) and the percentages of stages I+II, III and rapid eye movement(REM) sleep time were monitored by polysomnography(PSG). The cognitive function were assessed by montreal cognitive assessment before PSG. The levels of serum erythropoietin(EPO), neuron specific enolase(NSE) and S100β were detected by enzyme linked immunosorbent assay(ELISA). The cognitive function scores, serum levels of EPO, NSE, S100β and PSG parameters were compared among the four group patients, and the correlation among them were further evaluated using correlations analysis.Results The baseline characteristics in four groups show that only BMI was significantly different(P <0.05). Compared with primary snoring group, the AHI and(I + II) % in OSAHS groups were increased and the LSa O2, III% and REM% were decreased. The difference among four groups was significantly different(P <0.05). And there was significant difference of AHI and LSa O2 between mild and severe OSAHS groups(P<0.05). The difference of TST among four groups was not statistically significant. The Mo CA scores and delayed recall scores in OSAHS groups were lower than the scores in primary snoring group and the differences among four groups were statistically significant(P <0.05). The serum levels of S100β and EPO in OSAHS groups were higher than the levels in primary snoring group and the differences among four groups were statistically significant(P<0.05). The difference of serum NSE level among four groups was not statistically significant. The cognition scores were correlated negatively with AHI, S100β and EPO serum levels and correlated positively with LSa O2。The serum S100β levels was correlated negatively with LSa O2 and correlated positively with AHI(P <0.05)。The serum EPO levels was correlated positively with AHI and there was no significant correlation with LSa O2.Conclusion The decreased delayed recall ability was the most significant cognition impairment in patients with OSAHS. The increased serum levels of S100β and EPO was relevant to cognitive decline. And this may be the mechanism of cognition decline.