The correlationship study between the levels of serum Cystatin C and the cognitive dysfunction, the cerebral perfusion in Alzheimer's diesease patients

Abstract

Objective To explore the correlationship between Cystatin C and the cognitive dysfunction, encephalatrophy and the cerebral perfusion in Alzheimer's disease(AD) patients, and to analyze the probable mechanisms of the Cystatin C level alterations. Methods For the 61 male and 55 female AD patients, the levels of Cystatin C, Urea, Cr and β2-microglobulin were detected by biochemistry analysis.The hypocampus volume and Evans index were measured by MRI imaging.The cerebral perfusion was evaluated by magnetic resonance perfusion imaging of arterial spin labeling technique and image processing.The cognitive level of AD patients was done by MMSE scale and MoCA scale. Results The Cystatin C levels in serum of male AD patients were dramatically different from female AD patients(male: (0.95±0.20)mg/L, female: (1.32±0.41)mg/L)(P=0.04). For male AD patients, age and Cystatin C had a correlationship among the hypocampus volume((6157.14±355.58)mm3), Evans index(0.33±0.02), MMSE score(21.66±7.97), and MoCA score(21.96±6.19)(age: P=0.040, 0.049, 0.035, 0.039; Cystatin C: P=0.035, 0.038, 0.037, 0.035), but for female only age((79.52±8.82)years) had a correlationship with the hypocampus volume((6319.53±377.74)mm3), Evans index(0.31±0.02), MMSE score(22.93±6.22), and MoCA score(23.41±8.20)(P=0.044, 0.045, 0.047, 0.046). For male AD patients, the marked correlationship was showed between Cystatin C and the index of cerebral perfusion(P=0.034), but for female patients, there's no correlationship(P=0.086). Conclusion The Cystatin C level is distinctly different in male and female AD patients. The Cystatin C level in male AD patients maybe be an index to predict the degree of the cognitive dysfunction and the level of cerebral perfusion. Key words: Alzheimer's disease; Cystatin C; Encephalatrophy; Cognitive function; Cerebral perfusion