Study On The Value Of Serum S100β Protein And Homocysteine In The Diagnosis Of Mild Cognitive Impairment

Objective:To investigate the diagnostic value of serum S100β protein and homocysteine(Hcy)in mild cognitive impairment.Methods:In this study,91 patients with Alzheimer’s disease(AD)and mild cognitive impairment(MCI)were selected as the cognitive impairment group,including 42 patients with Alzheimer’s disease(AD group),49 patients with mild cognitive impairment(MCI group),and 35 healthy controls(HC group).Neuropsychological test and serum S100β and serum homocysteine(Hcy)were performed on all subjects.The differences of serum S100β protein and Hcy levels in each group were analyzed.Correlation analysis was used to evaluate the correlation between serum S100βprotein and Hcy levels and MMSE score and the scale of daily living ability score.The ROC curve was used to analyze the diagnostic value of serum S100β protein,Hcy level and S100β protein +Hcy for MCI and AD,and the area under the curve(AUC)was used to compare the diagnostic accuracy.Results:(1)The serum levels of S100β protein and Hcy in the cognitive impairment group were significantly higher than those in the HC group(p< 0.001).The S100βvalue in the AD group was higher than that in the MCI group(p=0.048).There was no significant difference in the Hcy value between the AD group and the MCI group(P =1).(2)Serum S100β protein and Hcy levels were negatively correlated with MMSE score and daily living ability scale score(p< 0.001).(3)Statistical analysis of ROC curve showed that the AUC of S100β protein +Hcy combined detection was 0.938 for MCI.The AUC of serum S100β and Hcy levels detected alone were 0.890 and 0.893(95%CI was 0.863-0.948 and 0.863-0.979,respectively),and the area under the curve of the combined detection was higher than that of the single detection(p< 0.001).The combined sensitivity and specificity were95.92% and 77.14%,respectively.(4)ROC statistical analysis showed that the AUC of S100β protein +Hcy was0.978 to assist in the diagnosis of AD,and the sensitivity and specificity were both improved.Conclusions:Serum S100β and Hcy levels were significantly increased in patients with cognitive impairment.Serum S100β value was related to the degree of cognitive impairment.Serum S100β and Hcy can be used as biomarkers for the diagnosis of MCI.The combined detection of S100β protein and Hcy can improve the accuracy and sensitivity of MCI diagnosis.Blood levels of these markers may be of some practical value in providing diagnostic assessments.