Walnuts and Healthy Aging

Conditions

Age Related Cognitive Decline, Age Related Macular Degeneration

Keywords

walnuts, age related cognitive decline, age related macular degeneration, healthy elderly subjects

Brief summary

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.

Detailed 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.

Cofán M, Checa A, Serra-Mir M, Roth I, Valls-Pedret C, Lopez-Illamola A, Doménech M, Rajaram S, Lázaro I, Sabaté J, Ros E, Wheelock CE, Sala-Vila A.

2023-12-091 citations

10.1016/j.tjnut.2023.12.007

Effect of Walnut Supplementation on Dietary Polyphenol Intake and Urinary Polyphenol Excretion in the Walnuts and Healthy Aging Study

Rita I. Amen, Rawiwan Sirirat, Keiji Oda, Sujatha Rajaram, Ifeanyi D. Nwachukwu et al. (9 authors)

Nutrients2023-03-023 citations

10.3390/nu15051253

Effect of a 2-year diet intervention with walnuts on cognitive decline. The Walnuts And Healthy Aging (WAHA) study: a randomized controlled trial.

Sala-Vila A, Valls-Pedret C, Rajaram S, Coll-Padrós N, Cofán M, Serra-Mir M, Pérez-Heras AM, Roth I, Freitas-Simoes TM, Doménech M, Calvo C, López-Illamola A, Bitok E, Buxton NK, Huey L, Arechiga A, Oda K, Lee GJ, Corella D, Vaqué-Alcázar L, Sala-Llonch R, Bartrés-Faz D, Sabaté J, Ros E.

2020-03-0172 citations

10.1093/ajcn/nqz328

Effect of a Walnut Diet on Office and 24-Hour Ambulatory Blood Pressure in Elderly Individuals

Mónica Doménech, Mercè Serra‐Mir, Irene Roth, Tania M. Freitas-Simoes, Cinta Valls‐Pedret et al. (12 authors)

Hypertension2019-03-1848 citations

10.1161/hypertensionaha.118.12766

The red blood cell proportion of arachidonic acid relates to shorter leukocyte telomeres in Mediterranean elders: A secondary analysis of a randomized controlled trial.

Freitas-Simoes TM, Cofán M, Blasco MA, Soberón N, Foronda M, Corella D, Asensio EM, Serra-Mir M, Roth I, Calvo C, Valls-Pedret C, Casaroli-Marano RP, Doménech M, Rajaram S, Sabaté J, Ros E, Sala-Vila A.

2018-02-1714 citations

10.1016/j.clnu.2018.02.011

The Walnuts and Healthy Aging Study (WAHA): Protocol for a Nutritional Intervention Trial with Walnuts on Brain Aging

Sujatha Rajaram, Cinta Valls‐Pedret, Montserrat Cofán, Joan Sabaté, Mercè Serra‐Mir et al. (21 authors)

Frontiers in Aging Neuroscience2017-01-1080 citations

10.3389/fnagi.2016.00333

Interventions

DIETARY_SUPPLEMENTWalnuts

30 to 60g (1 to 2 oz) per day of walnuts

OTHERhabitual diet

Dietary information will be provided

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

SINGLE (Investigator)

Eligibility

Sex/Gender

ALL

Age

63 Years to 79 Years

Healthy volunteers

Yes

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

Design outcomes

Primary

Measure	Time frame	Description
Changes from baseline in global cognitive composite score	2 years	The composite score will be calculated using the scores from the tests listed below. We will calculate the standardized scores of each test as the score of each participant minus the group mean and divide by its standard deviation. The composite score is the mean of the standardized scores. The 12 tests are: Rey Auditory Verbal Learning Test (RAVLT), Rey-Osterrieth Complex Figure (ROCF), Semantic Fluency (Animals), Boston Naming Test (BNT), Visual Object and Space Perception Battery (VOSP), Block Design section from the Wechsler Adult Intelligence Scale (WAIS-III), Trail Making Test (TMT), FAS Word Fluency, Stroop Color Word Test, Symbol Digit Modalities Test (SMDT) Digit Span from the WAIS-III and Conners Continuous Performance Test (CPT-II).
Changes from baseline in macular degeneration	2 years	This will be assessed: by stereoscopic digitized color fundus images graded by International Classification System for Age-Related Maculopathy (score range. 0 to 4; the higher the score, the worse the condition); by optical coherence tomography (OCT) measurements of macular thickness (in µm); by optical coherence tomography (OCT) measurements of retinal nervous fiber layer thickness (in µm).

Secondary

Measure	Time frame	Description
Change from baseline in white matter hyperintensity volumes	2 years	Changes will be assessed by brain magnetic resonance imaging (MRI) on a randomly selected subset of participants. Only in Barcelona center. Unit of measure is mL.
Change from baseline in brain cortical thickness	2 years	Changes will be assessed by brain magnetic resonance imaging (MRI) on a randomly selected subset of participants. Only in Barcelona center. Unit of measure is mm2.
Changes from baseline in brain activation	2 years	Changes will be assessed by Functional MRI (fMRI) on a randomly selected subset of participants. Only in Barcelona center. There are no units of measure.
Change from baseline in perfusion arterial spin labeling	2 years	Changes will be assessed by brain magnetic resonance imaging (MRI) on a randomly selected subset of participants. Only in Barcelona center. Unit of measure is ml/100 g/min.
Change from baseline in voxel-based morphometry	2 years	Changes will be assessed by brain magnetic resonance imaging (MRI) using GM density maps on a randomly selected subset of participants. Only in Barcelona center. Unit of measure is GM density.

Other

Measure	Time frame	Description
Change in fasting serum total cholesterol (mg/dL)	2 years	Fasting serum total cholesterol will be measured by a standard enzymatic method
Change in fasting serum LDL-cholesterol (mg/dL)	2 years	Fasting serum LDL-cholesterol will be estimated by the Friedewald formula
Change in fasting serum HDL-cholesterol (mg/dL)	2 years	Fasting serum HDL-cholesterol will be measured by a precipitation technique
Change in fasting serum triglycerides (mg/dL)	2 years	Fasting triglycerides will be measured by a standard enzymatic method
Change in serum brain-derived neurotrophic factor (pg/mL)	2 years	Assessed by ELISA
Change in serum soluble-Selectin (ng/mL)	2 years	Assessed by ELISA
Change in serum soluble-intercellular Adhesion Molecule 1 (ng/mL)	2 years	Assessed by ELISA
Change in carotid Intima-media thickness (mm)	2 years	Changes will be assessed by high-resolution ultrasound. Only in Barcelona center.
Change in serum amyloid A (ng/mL)	2 years	Assessed by ELISA
Change in serum granulocyte-macrophage colony-stimulating factor (pg/mL)	2 years	Assessed by ELISA
Change in serum interferon-gamma (pg/mL)	2 years	Assessed by ELISA
Change in serum interleukin-1beta (pg/mL)	2 years	Assessed by ELISA
Change in serum interleukin-6 (pg/mL)	2 years	Assessed by ELISA
Change in serum tumor necrosis factor alpha (pg/mL)	2 years	Assessed by ELISA
Change in serum soluble-vascular cell adhesion molecule 1 (ng/mL)	2 years	Assessed by ELISA
Incidence of plaque presence in carotid artery (yes/no)	2 years	Changes will be assessed by high-resolution ultrasound. Only in Barcelona center.
Change in carotid atheroma plaque height (mm)	2 years	Changes will be assessed by high-resolution ultrasound. Only in Barcelona center.
Change in body mass index (kg/m2)	2 years	BMI will be calculated as weight in kilograms divided by height in metres squared
Change in waist circumference (cm)	2 years	Waist circumference will be measured to the nearest 0.5 cm by using an anthropometric tape midway between the lowest rib and at the iliac crest at minimal respiration
Change in total fat (g)	2 years	Changes will be assessed by Dual-energy X-ray absorptiometry. Only in Barcelona center.
Change in Total lean tissue (g)	2 years	Changes will be assessed by Dual-energy X-ray absorptiometry. Only in Barcelona center.

Countries

Spain, United States

Outcome results

None listed