Cognitive Status And Its Relationship With Serum Neuropeptide Y In Patients With Obstructive Sleep Apnea-hypopnea Syndrome

Objective:To verify the reliability and validity of MoCA in assessing the cognitive function of patients who are with obstructive sleep apnea-hypopnea syndrome(OSAHS),to detect the serum neuropeptide Y(NPY)levels and to explore its correlation with neurocognitive impairment,provide the basis and basis for further exploration of the mechanism of cognitive impairment in OSAHS.METHODS:A total of 72 OSAHS patients of varying severity treated for snoring at the Sleep Center of Huainan First People's Hospital affiliated to Bengbu Medical College from July 2016 to November 2017 were enrolled in a case-control study.All patients underwent multiple guided Sleep monitoring(PSG)was diagnosed and divided into non-severe OSAHS group and severe OSAHS group by sleep apnea-hypopnea index(AHI).In the same period,16 volunteers were collected as the control group.All controls excluded sleep disorders and other factors that could cause cognitive dysfunction,and matched the education level,age and gender of the patients.All subjects were underwent MoCA test and MMSE test.After 14 days,10 subjects in the control group were randomly selected to be conducted a MoCA retest,then the internal consistency of MoCA was analyzed using the Cronbach's alpha test,and the Pearson correlation coefficient was used to test the retest reliability.At the same time,the concurrent validity of MoCA was evaluated by comparing with MMSE.In addition,serum NPY levels were measured by enzyme-linked immunosorbent assay(ELISA)in all subjects.The correlation between serum NPY level and MoCA total score or its subscales score was analyzed,and to explore the relationship between serum NPY level and neurological cognition in patients with OSAHS.Results:With the severity of OSAHS increasing,the prevalence of hypertension,BMI,AHI and TS90%increased,and the nighttime minimum oxygen saturation(L-Sa02),average oxygen saturation(A-Sa02)showed a decreasing trend,and the differences among the groups were statistically significant(all P<0.01).Data representing sleep patterns(sleep efficiency,latency to REM,rates of stage ? + ?,rates of REM and ?+ ?)were not significantly different between patients with different severity.In addition,the internal consistency of MoCA detected by Cronbach's alpha is reliable(0.690).If you delete only the term "directional ability",its Cronbach's coefficient a will become 0.705.Therefore,our results indicate that MoCA's internal consistency reliability is generally adequate for assessing cognitive function in adult OSAHS patients,and its internal consistency reliability can be increased with the deletion of directional ability.Pearson correlation coefficient test retest reliability(r =0.884,P = 0.001).Correlation analysis between MoCA and MMSE scores showed that the MoCA score was significantly correlated with the MMSE score(r = 0.701,P<0.01).Therefore,the concurrent validity of MoCA was reliable.At the same time,we found that serum NPY level gradually increased and MoCA score decreased gradually with the severity of the disease increasing(all P<0.01).MMSE scores were no significant difference between groups(control group,mild patients and moderate,severe patients),but the difference between the patients and the control group was significant;moderate and severe OSAHS patients in serum NPY levels were higher than the healthy control group,and lower in MoCA score(P<0.05).Cognitive impairment mainly in visual space,attention,numerical knocking test and language ability,and executive ability,computational ability,abstraction,naming,delayed recall and orientation ability between the groups was not statistically significant.The study further analyzed the correlation between subjects' general clinical data,PSG parameters,serum total NPY and MoCA scores and their subscales scores.Pearson correlation analysis showed that serum NPY levels were positively correlated with hypoxic parameters AHI and TS90%,negatively correlated with L-Sa02 and A-Sa02,but not significantly;MoCA score was negatively correlated with age(r?-0.339),but positively correlated with education level(r = 0.421)(all P<0.05).The MOCA score was negatively correlated with serum NPY level(r =-0.105),but the correlation was not significant.Conclusion:(1)MoCA is reliable,stable,and effective in assessing the cognitive abilities of adult OSAHS,and after removing the "orientation ability",the internal consistency reliability is increased;(2)The score of cognitive function in OSAHS patients decreased,and it became obvious as the severity of the disease increased.The cognitive impairment in OSAHS patients is mainly manifested in visual aptitude,language ability,and attention;(3)Serum NPY levels in patients with OSAHS increased,and increased with the severity of the disease,so serum NPY can be used as a serum marker reflecting the severity of OSAHS;(4)There was a negative correlation between cognitive function and serum NPY levels in OSAHS patients,but the correlation was not significant.Therefore,whether NPY can be used as a specific marker to evaluate the cognitive abilities of OSAHS patients remains to be further verified.