Consumption of Potatoes, Avocados and Chickpeas and Cognitive Function in Older Adults

The Effect of Consumption of Potatoes, Avocados and Chickpeas Daily for 6 Months on Cognitive Function in Older Adults

Cognitive impairment is also a major risk factor for development of dementia later in life. Findings from the investigators studies suggest that the carotenoids, lutein and zeaxanthin may be important in cognitive function in the elderly. Avocados are a source of these carotenoids. The investigators study evaluates long-term avocado intervention as a treatment strategy for age-related cognitive impairment which could possibly prevent the onset of dementia. The investigators have also shown that lutein supplementation significantly improved verbal fluency scores in healthy older women. Based on these findings, the next logical step will be to investigate the ability of lutein and zeaxanthin contained in avocados to influence cognitive function in older adults. The investigators hypothesize that there will be a significant increase in cognitive function measures in older adults provided with meals containing 1 avocado/day at the end of 6 months, while no significant improvements will be observed in older adults given daily meals containing chickpeas and/or potatoes.

The proposed study is designed as a randomized, placebo controlled trial that tests the effects of 6 month supplementation with 1 avocado/day on cognitive function in older adults. Secondary analyses will determine whether baseline macular pigment (lutein in retina which canbe measured non invasivley) density predicts relative effectiveness of the intervention on cognitive function. Secondary outcomes include plasma biomarkers of oxidative stress and inflammation.

Study Overview

• Status: Completed
• Conditions: Mild Cognitive Impairment
• Intervention / Treatment: Other: potato or chickpea; Other: avocado

Detailed Description

The study is designed as a placebo controlled trial that tests the effects of 6 month supplementation with daily meals containing 1 avocado or isocaloric amounts of chickpeas and/or potatoes on cognitive function in older adults. Subjects will be randomly assigned to one of the two groups. Secondary analyses will determine whether baseline macular pigment density (a non invasive measure of lutein and zeaxanthin in neural tissue) predicts relative effectiveness of the intervention on cognitive function. Secondary outcomes include plasma biomarkers of oxidative stress and inflammation. Participants will be recruited from community-dwelling men and women aged >50 yr, and potential participants will be screened to meet cognitive and functional criteria. Participants will be pre-screened by telephone; those who appear to meet criteria will undergo further screening. The study will include baseline (0 month), 3 and 6 month visits for study procedures, and monthly telephone calls. Given that there is a visible difference between the two interventions, a blinded study is not possible.

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02111
      • Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• men and women age > 50 years
• BMI 19-30 kg/m2
• lutein intake of < 3 mg/d
• Docosahexaenoic acid intake < 250 mg/d (including supplements)
• Mini mental state exam (MMSE) score > 24
• Macular pigment density < 0.4 at 0.5 degrees
• Beck Depression Inventory < 20
• free of known disease
• BMI 19-29 kg/m2
• must be able to give written informed consent
• have normal hematologic parameters
• normal values of plasma albumin
• normal values for liver and kidney function (Appendix A)
• no use of carotenoid, n3 fatty acid, multivitamin/mineral, (> 2 months).

Exclusion Criteria:

• history of active small bowel disease or resection
• atrophic gastritis
• hyperlipidemia (LDL >120 mg/dL or triglycerides >150 mg/dL)
• hypertension (>150/90 mm Hg)
• diabetes, alcoholism (>2 drinks/d or 14 drinks/week)
• pancreatic disease
• anemia, and bleeding disorders (as determined by screening interview)
• avocado, potato or chickpea allergy
• pregnancy or lactation
• diseases that interfere with fat absorption, e.g. colitis, celiac disease, Crohn's disease, cystic fibroids (as determined by screening interview)
• medications that interfere with fat absorption, e.g. bile sequestrants (as determined by screening interview)
• use of antipsychotic, antimanic, anti-inflammatory, monoamine inhibitors, or dementia medications
• smoking or use of nicotine patches or gum (within past 6 months)
• use of drugs suspected of interfering with metabolism of blood clotting, e.g. warfarin (as determined by screening interview)
• subjects having extremely high dietary intakes of carotenoids as indicated by screening plasma values > NHANES 95th percentile for lutein/zeaxanthin, beta-carotene, cryptoxanthin, or lycopene
• stroke,head injury with loss of consciousness or seizures.
• Non English speaking: This is a small study with a sample size. Logistically and financially, getting materials translated for such a small study is not feasible.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
PLACEBO_COMPARATOR: chickpeas/potatoes; 1 potato/day or 1 cup chickpeas	Other: potato or chickpea; 1 cup potatoes or chickpeas/day for 6 months
ACTIVE_COMPARATOR: avocados; 1 avocados/day	Other: avocado; 1 avocado/day for 6 months

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognition	measures of sustained attention will be made using CANTAB, a sensitive computerized program. Signal detection measured on a scale from 0 to 1(bad to good).	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inflammation	C-reactive protein	0 months
Inflammation	C-reactive protein	3 month
Inflammation	C-reactive protein	6 month

Collaborators and Investigators

• Sponsor: Tufts University
• Investigators: Principal Investigator: Elizabeth J Johnson, Ph.D., Tufts University

Study record dates

Study Major Dates

• Study Start: August 1, 2012
• Primary Completion (ACTUAL): August 1, 2014
• Study Completion (ACTUAL): August 1, 2014

Study Registration Dates

• First Submitted: June 13, 2012
• First Submitted That Met QC Criteria: June 14, 2012
• First Posted (ESTIMATE): June 15, 2012

Study Record Updates

• Last Update Posted (ACTUAL): July 19, 2019
• Last Update Submitted That Met QC Criteria: May 8, 2019
• Last Verified: May 1, 2019

More Information

Terms related to this study

• Keywords: elderly; lutein; avocados; chickpeas; potatoes
• Additional Relevant MeSH Terms: Mental Disorders; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction
• Other Study ID Numbers: 002 (University of CT Health Center)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No