Cognitive Impairment, no Dementia (CIND)
Conditions
Brief summary
ENLIGHTEN will examine the effects of exercise, the dietary approaches to stop hypertension diet (DASH), and a combined exercise and DASH intervention on cognitive function among adults with cardiovascular disease (CVD) risk and cognitive deficits. Participants will be randomized to one of the three treatments, or a health education control condition, for 6 months, and will complete assessments of CVD health and cognitive function before and after treatment.
Detailed description
Cardiovascular disease (CVD) is the leading cause of death and disability in the United States, affecting more than 81 million American adults. It is well established that risk factors such as hypertension, diabetes, and hyperlipidemia not only place individuals at risk for CVD, but also place them at risk for neurocognitive impairment and dementia. CVD risk factors have been shown to be associated with a cascade of neurophysiologic and neuroanatomic changes, resulting in cognitive impairment and dementia. Exercise and diet have been shown to improve CVD risk factors and also appear particularly promising lifestyle approaches for preventing dementia among individuals at risk, such as those with cognitive impairment, no dementia (CIND). ENLIGHTEN is a randomized clinical trial of diet and exercise among patients with CIND.
Interventions
BEHAVIORALAerobic Exercise
Participants will exercise for 6 months. In the initial 3-month supervised phase, patients will exercise 3 times a week at a level of 50-75% of their initial peak heart rate reserve (HRR) or at their peak heart rate without symptoms, or ST-segment depression \> 1 mm, as determined at the time of their initial exercise test. Aerobic exercise consists of 10 minutes of warm-up exercises followed by 30 minutes of continuous walking or (stationary) biking. Each exercise session will conclude with a 10 minute period of cool-down exercises. During weeks 13 to 24 (i.e., home maintenance phase), participants will be asked to perform 3 aerobic sessions per week at home at 60-70% HRR.
BEHAVIORALDASH diet
Participants in the DASH condition only receive instruction in modifying the content of their diet to meet DASH guidelines. Participants will be explicitly asked not to exercise and to focus their attention on what they eat. Participants will have been told (in the initial consent form) that the study is designed to study effects of two interventions (altering diet content and exercise) both of which have been shown to improve health. Participants will also be told that it may be easier or more effective for them if they focus first on learning to alter diet content, and they are free to exercise at the end of the 6-month period. Following an initial 1-day feeding period, participants, along with their study partners, will receive instruction on the DASH diet and feedback on their adherence to the diet in a series of half-hour, weekly small group sessions (3 to 4 participants).
The Health Education control group will receive weekly 30-min lectures on relevant, health-related topics but will not receive instruction in the DASH diet nor will exercise be promoted. These participants will be asked to maintain their usual dietary and exercise habits for 6 months until they are re-evaluated. These sessions are designed to provide useful information about medical aspects of CVD, but will not provide instruction in the DASH diet or exercise.
Sponsors
Duke University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
55 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 55 years or older * Sedentary * Score of 19-25 on the Montreal Cognitive Assessment Battery or verbal fluency score of =\< 12 or animal fluency score of =\<15 * At least one cardiovascular risk factor (hypertension, diabetes, cholesterol, obesity, current smoking, or family history) or a documented history of cardiac disease (myocardial infarction, coronary artery bypass grafting, peripheral vascular disease, \>70% stenosis, or mild stroke without residual deficit)
Exclusion criteria
* Any significant neurological disease other than CIND, such as Parkinson's disease, multi-infarct dementia, Huntington' s disease, progressive supranuclear palsy, brain tumor, normal pressure hydrocephalus, subdural hematoma, seizure disorder, multiple sclerosis, or history of head trauma with persistent neurological deficits * Psychotic disorder within the past two years (DSM IV criteria) or acutely suicidal * History of alcohol or substance abuse or dependence within the past two years (DSM IV criteria) * History of schizophrenia * Any significant systemic illness or unstable medical condition that could lead to difficulty in complying with the protocol including a history of systemic cancer within the past 5 years (nonmetastatic skin cancers are acceptable) * Myocardial infarction (within the past 3 months) or unstable or severe congestive heart failure (e.g. class III-IV heart failure) * End-stage pulmonary disease; uncontrolled diabetes mellitus or uncontrolled hypertension(systolic BP\>170 or diastolic BP \>100 mm Hg on medication) * Musculoskeletal disorders precluding the ability to exercise (e.g. severe arthritis)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Executive Function | Baseline to post-treatment assessment at 6 months | Composite executive function measure includes Trail Making Test, Stroop Test, Digit Span, Digit Symbol Substitution Test, Ruff 2 & 7 Test, and Animal Naming Test |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Fasting glucose | 6 months | We will also assess treatment effects on measures fasting glucose |
| Cholesterol | 6 months | We will also examine treatment effects on cholesterol, including LDL, HDL, and total cholesterol |
| Change in Memory | 6 months | Secondary outcomes will include composite measures of memory (Hopkins Verbal Learning Test-Revised and Medical College of Georgia Complex Figure Test) |
| Change in Language | 6 months | Secondary outcomes will include composite measures of language (Controlled Oral Word Association Test and Animal Naming Test) |
| Intima-medial thickness | 6 months | We also will examine treatment effects on the vascular function measures, including intima-medial thickness of the carotid artery. |
| Functional Capacity | 6 months | Functional capacity (6MWT and peak VO2). Six-minute walk distance (6MWT) and peak VO2 from a treadmill test will be assessed by an exercise physiologist. |
| Blood Pressure | 6 months | We also will examine treatment effects on the vascular function measures, including blood pressure. |
| Flow-mediated dilation of the brachial artery | 6 months | We also will examine treatment effects on the vascular function measures, including flow-mediated dilation of the brachial artery. |
| Arterial Stiffness | 6 months | We also will examine treatment effects on the vascular function measures, including pulse-wave velocity of the femoral artery. |
| Inflammation | 6 months | We will also assess treatment effects on measures of inflammation, including C-reactive protein and interleukin-6. |
Countries
United States
Outcome results
None listed