The study on cognitive changes of working memory network in patients with essential hypertension based on task-functional MRI

Objective To analyze the function of essential hypertension′s working memory network by using task-fMRI and independent component analysis (ICA). Methods According to the enrollment criteria, 24 hypertensive patients and 23 healthy controls (May 2016 to January 2017) in the 900 Hospital of the Joint Service Support Force were collected, who underwent task-state functional MRI data acquisition of N-back by using Siemens 3.0 T MRI. All subjects completed neuropsychological cognitive tests, blood pressure measurements and biochemical tests before MRI. Task-state functional MRI was analyzed by SPM 12, and independent component analysis was performed by GIFT 4.0 software. The independent-samples t-test was used to analyze the maps of the two groups′s task-state fMRI and ICA. The results were adjusted by multiple comparison correction of Alphasim, P<0.05 showed that the difference was statistically significant. Results Compared with the healthy group, the activation of left superior frontal gyrus and left middle frontal gyrus in hypertension group was enhanced (P<0.05), but there was no obvious weakened activation area. In the independent component analysis, the functional connectivity of left middle frontal gyrus and left anterior central gyrus in hypertension group was significantly lower than that in healthy control group (P<0.05), and there was no significant enhancement of functional connectivity. Conclusions The working memory network of patients with essential hypertension may change abnormally due to the influence of long-term hypertension. This kind of damage can compensate through the functional enhancement of brain regions, thus maintaining the normal cognitive level of hypertensive patients. Key words: Hypertension; Magnetic resonance imaging; Memory