Cardiovascular Risk Factors and Cognitive Trajectories

Study Overview
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Brief Summary
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The cognitive trajectory varies among non-demented older adults. In a 12-year follow-up study, we found approximately 5% participants presented rapid cognitive decline. Cardiovascular diseases increased the risk of cognitive decline. However, the influence of cardiovascular risk factors on cognitive decline remained inconsistent. Besides, the potential mechanism of the cardiovascular risk factors and cognitive function has not been fully investigated. Therefore, the proposed program will include two sub-studies. The first sub-study will use the longitudinal data from the Chinese Longitudinal Healthy Longevity Survey to evaluate the influence of cardiovascular risk factors on the trajectories of cognitive function. The second sub-study will recruit cognitive intact older adults with different levels of cardiovascular risk factors. The association among cardiovascular risk factors, cerebral blood flow, brain functional connectivity and cognitive function will be investigated with structural equation modeling. The findings of the proposed program will provide novel insight on preventing cognitive decline from the angle of maintaining healthy vascular function, and will provide evidence in elucidating the potential neurovascular mechanism between cardiovascular risk factors and cognitive function.

Official Title
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The Influence and Potential Mechanism of Cardiovascular Risk Factors on the Cognitive Trajectories Among Cognitively Intact Older Adults

Conditions
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Normal Cognition, Cardiovascular Risk Factors, Cognitive Change, Cerebral Blood Flow, fMRI

Participation Criteria
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Eligibility Criteria
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For the cognitive trajectory cohort (the data had been collected): Inclusion Criteria: Aged 65 or over at baseline; With normal cognitive function at baseline (score ≥ 18 on the Chinese version of Mini-Mental State Examination, MMSE); Had at least one domain information about cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, exercise, diet and smoking) at baseline; Completed cognitive function assessment at least twice during 3 waves following-up after baseline; Provided informed consent voluntarily. Exclusion Criteria: Aged <65; had a history of dementia or MMSE score < 18 at baseline; Without more than once cognitive function assessment during the follow-up; Refused to participate the survey. For the neuroimaging sample, who would be enrolled by this study: Inclusion Criteria: Aged 55-80; Right-handed; Primary school education or above, with normal communication ability; No complaints of cognitive impairment or decline; MMSE score ≥ 26; Clinical dementia rating (CDR) =0; Provided informed consent voluntarily. Exclusion Criteria: Severe visual or hearing impairment, difficult to complete cognitive function assessment; Had contraindications to magnetic resonance examination, such as claustrophobia, cardiac pacemaker and artificial heart valve; Had cardiovascular diseases (such as myocardial infarction and unstable angina pectoris), severe respiratory diseases, malignant tumors, renal failure and other serious physical diseases; Had diseases that could affect cognitive function, such as hypothyroidism, syphilis, vitamin B12 deficiency and anemia; Had a history of any mental disease; Had a history of cerebrovascular disease, or obvious space occupying lesions in the brain revealed by magnetic resonance examination; Refused to participate the survey.

Ages Eligible for Study
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Minimum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| cognitive trajectory cohort<br>Th cognitive trajectory cohort, based on CLHLS dataset, will be used to evaluate the influence of cardiovascular risk factors on the cognitive trajectories among cognitively intact older adults | |
| neuroiming sample<br>The neuroiming sample, including cognitively intact older adults with MRI data, will be used to explore the potential mechanism of the cardiovascular risk factors and cognitive function. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Regression coefficients | the influence of cardiovascular risk factors on cognitive change | up to 10 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the correlation coefficient | the relationship among cognitive function score, value of cerebral blood flow, and functional connectivity strength | baseline |