Walnuts and Healthy Aging (WAHA)

Loma Linda University (LLU)

Status: Completed

Conditions: Age Related Macular Degeneration; Age Related Cognitive Decline

Treatments: Other: habitual diet; Dietary Supplement: Walnuts

Study type: Interventional

Funder types: Other

Identifiers

NCT01634841

670715-3833 (Other Identifier)

5120066

Details and patient eligibility

About

This will be a systematic investigation of the role of walnuts in preventing or slowing age related cognitive decline and age related macular degeneration. 700 subjects will be recruited between 2 sites, Loma Linda University in California, USA and Hospital Clinic in Barcelona, Spain. Participants will be randomly assigned to either the walnut group or the control group for a 2 year intervention. Baseline and annual data will be collected and analyzed.

Full description

Epidemiological studies suggest that nutrients such as n-3 polyunsaturated fatty acid, antioxidants and B-vitamins may protect against age related cognitive decline. Small human studies have shown beneficial effects of polyphenol rich foods on cognition and age related macular degeneration. Walnuts are a rich source of n-3 polyunsaturated fatty acid, alpha-linolenic acid, antioxidants, polyphenols and other bioactive compounds. A 2-year intervention will be conducted with healthy, elderly subjects to investigate the role of walnuts in preventing or slowing age related cognitive decline and age related macular degeneration.

350 subjects, age 63 to 79 years, will be recruited at each of 2 sites, Loma Linda University in California and Hospital Clinic in Barcelona. Participants will be randomly assigned to one of two groups: walnut group (habitual diet with 1 or 2 oz/d walnut supplement) or control group (habitual diet only). At baseline and yearly, cardiometabolic risk factors, red blood cell membrane fatty acids, urinary polyphenols and biomarkers of inflammation and oxidation will be measured. Eye exam, blood pressure and cognitive function tests will be measured at the beginning and end of 2 years. At the Barcelona site only, participants will be given a brain MRI and carotid ultrasound.

Descriptive results will be reported as mean plus/minus standard deviation. Primary analysis will be carried out on the basis of groups as randomly assigned. Results will be presented as appropriate effect sizes with a measure of precision (95% CI). Analysis of covariates gender, age, educational status will be conducted.

Enrollment: 708 patients

Sex: All

Ages: 63 to 79 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 63 to 79 years old
• healthy men and women
• able to attend clinic at a study sites

Exclusion criteria

• illiteracy or inability to understand the protocol
• unable to undergo neurophysiological tests
• morbid obesity (BMI greater than or equal to ≥ 40 kg/m2)
• uncontrolled diabetes (HbA1c>85)
• uncontrolled hypertension
• prior cerebrovascular accident
• any relevant psychiatric illness, including major depression
• advanced cognitive deterioration, dementia
• other neurodegenerative diseases (i.e. Parkinson's disease)
• any chronic illness expected to shorten survival (heart, liver, cancer, etc)
• bereavement in the first year of loss
• bad dentures unless fixable dental prostheses are used
• allergy to walnuts
• customary us of fish oil or flaxseed oil supplements
• eye related exclusion criteria

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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708 participants in 2 patient groups

Walnut group

Active Comparator group

Description:

This group will have their habitual diet supplemented with 30 to 45g (1 to 1.5 oz) of walnuts daily.

Treatment:

Dietary Supplement: Walnuts

Control group

Active Comparator group

Description:

This group will eat their habitual diet and refrain from eating walnuts.

Treatment:

Other: habitual diet