Purpose: To investigate the associations between concentrations of Aβ₄₀ and Aβ₄₂ and vascular cognitive impairment (VCI) in cerebral small vessel disease (CSVD) patients and evaluate the value of combination of levels of Aβ₄₀ or Aβ₄₂ and the total CSVD score in predicting VCI.
Patients and Methods: A total of 199 CSVD patients were divided into VCI group and non-VCI group according to the criteria of VCI. Demographic data, MRI markers of CSVD, blood pressure, vascular risk factors, laboratory markers, and serum Aβ₄₀ and Aβ₄₂ concentration were collected. Univariate analysis was performed with the Student’s t -test, Mann–Whitney U -test or Chi-square test. Variables with P < 0.10 in univariate analysis were then included in multivariate analysis that used a backward stepwise logistic regression model. The predictive values were assessed with receiver operating characteristic (ROC) curve.
Results: VCI was determined in 112 CSVD patients (56.3%). Hyperlipidemia (OR: 1.618, 95% CI: 1.265– 3.049), the total CSVD score (OR: 1.414, 95% CI: 1.213– 2.278) and serum Aβ₄₂ concentration (OR: 1.401, 95% CI: 1.212– 1.946) were independent risk factors for VCI in CSVD patients with adjustment for age, education years, diabetes and fasting blood-glucose (FBG). The area under curves (AUCs) were 0.640 (SE: 0.040, 95% CI: 0.563– 0.718), 0.733 (SE: 0.035, 95% CI: 0.664– 0.802) and 0.827 (SE: 0.030, 95% CI: 0.768– 0.887), respectively, for the total CSVD score, serum Aβ₄₂ concentration and their combination applied in predicting VCI in CSVD patients. Z  test demonstrated that the AUC of combination prediction was significantly higher than individual prediction (0.827 vs 0.640, Z =3.740, P < 0.001; 0.827 vs 0.733, Z =2.039, P =0.021).
Conclusion: Combination of Aβ₄₂ and total CSVD score could significantly elevate the predictive value of cognitive impairment in CSVD patients.
Keywords: Aβ₄₀, Aβ₄₂, vascular cognitive impairment, cerebral small vessel disease, total cerebral small vessel disease score