Clinical Interventions in Aging (Jul 2014)
Relationship between cognitive impairment and apparent diffusion coefficient values from magnetic resonance-diffusion weighted imaging in elderly hypertensive patients
Abstract
Yanwei Zhao,1 Gang Wu,2 Haiming Shi,3,4 Zhijie Xia,1 Tao Sun3,4 1Emergency Department, Huashan Hospital North, Fudan University, Shanghai, People’s Republic of China; 2Emergency Department, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China; 3Cardiology Division, Huashan Hospital North, 4Cardiology Division, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China Background: The purpose of this study was to determine a new method for the early diagnosis and assessment of mild cognitive impairment in elderly individuals with hypertension. Elderly hypertensive patients with cognitive impairment were assessed by the Montreal Cognitive Assessment (MoCA) and Clinical Dementia Rating Assessment (CDR). Cognitive results were compared to apparent diffusion coefficient (ADC) values from magnetic resonance-diffusion weighted imaging. Methods: A total of 191 patients were categorized into four groups: a control group (normal cognition and no hypertension; n=20); a normal group (hypertension and normal cognition; n=33); an mild cognitive impairment group (n=80); and a vascular dementia group (n=58). The MoCA and CDR tests were used to determine cognition. ADC values in eight brain regions were calculated with magnetic resonance-diffusion weighted imaging. Other characteristics were evaluated, eg, blood pressure, MoCA, and CDR scores, and the comparisons of the four groups were made. Results: The MoCA and CDR scores differed among the four groups (P<0.001). Systolic and diastolic blood pressure values increased as cognitive function declined (P<0.001). Cognitive function declined as ADC values increased, and they differed between elderly people with and without hypertension (P<0.001). Among elderly hypertensive participants, ADC values were significantly increased in the cortex and hippocampus. Conclusion: The MoCA and CDR tests were sufficiently sensitive to evaluate cognition. Blood pressure was closely related to cognition, as well as to functional and structural changes in the brain. These alterations were evidenced through changes in the ADC values and were most obvious in the cortex and hippocampus. Greater cognitive decline was observed in elderly participants with hypertension compared to those without. As hypertensive stage increased, greater ADC values were observed. Keywords: Clinical Dementia Rating Assessment, hypertension, mild cognitive impairment, Montreal Cognitive Assessment
