Study on mechanism of cerebral blood flow and cognitive impairment related to white matter hyperintensity

Abstract

Objective To explore the relationship between alteration of cerebral blood flow (CBF) and cognitive impairment in patients with white matter hyperintensity (WMH). Methods Eighty patients with WMH and 37 controls matching sex, age and education were enrolled. Patients with WMH were divided into mild WMH group (n=33, Fazekas score 1-2) and moderate⁃severe WMH group (n=47, Fazekas score 3-6). Montreal Cognitive Assessment (MoCA), Chinese Auditory Verbal Learning Test (CAVLT), Symbol Digit Modalities Test (SDMT), Color Trail Test (CTT) and Boston Naming Test (BNT) were respectively used to assess overall cognitive function, memory, attention, executive function and language. The 3D⁃pseudo⁃continuous arterial spin labeling (3D⁃pCASL) was used to assess CBF. The relationship between CBF and cognitive function was estimated by Pearson correlation and partial correlation analyses. Results 1) MoCA (F=3.433, P=0.036), CAVLT⁃study (F=4.123, P=0.019), CAVLT⁃immediate (F=7.929, P=0.001), CAVLT⁃delay (F=6.738, P=0.002), CAVLT⁃recognition (F=5.762, P=0.004), SDMT (F=5.136, P=0.008), CTT⁃A (F=7.155, P=0.001) and BNT (F=4.329, P=0.032) were statistically significant among 3 groups. The moderate⁃severe WMH group was less than control group in MoCA (t=2.525, P=0.013), CAVLT⁃study (t=2.683, P=0.009), CAVLT⁃immediate (t=3.593, P=0.004), CAVLT⁃delay (t=3.497, P=0.001), CAVLT⁃recognition (t=3.264, P=0.002), SDMT (t=3.170, P=0.002), BNT (t=2.584, P=0.011) as well as less than the mild WMH group in CAVLT⁃study (t=2.025, P=0.046), CAVLT⁃immediate (t=3.033, P=0.003), CAVLT⁃delay (t=2.458, P=0.016) and CAVLT⁃recognition (t=2.181, P=0.032), while more than control group in CTT⁃A (t=⁃3.668, P=0.000). The mild WMH group was more than control group in CTT⁃A (t=⁃2.697, P=0.008). 2) The CBF of right putamen, left putamen and right median cingulate were statistically significant among 3 groups [Gaussian random field (GRF) corrected, cluster P＜0.05, voxel P＜0.001]. Compared to control group and the mild WMH group, the CBF of the right putamen (t=5.039, P=0.000; t=3.672, P=0.000), the left putamen (t=5.808, P=0.000; t=2.665, P=0.009) and right median cingulate (t=5.038, P=0.000; t=3.319, P=0.001) were more in the moderate⁃severe WMH group. Compared to the control group, the CBF of the right median cingulate was higher in the mild WMH group (t=1.476, P=0.006). 3) The correlation analysis showed that in the mild WMH group, the CBF of the right putamen was positively correlated with SDMT (r=0.478, P=0.028), and negatively correlated with CTT⁃A (r=⁃0.483, P=0.026), the CBF of left putamen was positively correlated with MoCA (r=0.451, P=0.040), and negatively correlated with CTT⁃A (r=⁃0.502, P=0.020), the CBF of right median cingulate was positively correlated with MoCA (r=0.446, P=0.043); in the moderate⁃severe WMH group, the CBF of the right putamen was positively correlated with CAVLT⁃recognition (r=0.343, P=0.043). Conclusions The alteration of CBF in the brain may be a possible neuropathological mechanism of WMH and relate to cognitive impairment in WMH.

Keywords

• cerebral small vessel diseases
• hemoperfusion
• cognition disorders
• magnetic resonance imaging