Effect of Raisins on Cognitive Function in Healthy Older Adults

Effect of Supplementing the Diet With Raisins, a Food Rich in Polyphenols, on Cognitive Function in Healthy Older Adults, a Randomised Controlled Trial

Objective:To assess the effect of an intervention based on including 50 g of raisins (sultanas) daily in the diet for 3 months on improving cognitive performance, cardiovascular risk factors and inflammatory markers in a population of older adults without cognitive impairment.

Methodology: Randomised two parallel-group clinical trial. Population: 80 patients between 70 and 80 years of age will be included, selected from primary care clinics in Salamanca and Zamora.

Measurements and intervention: Participants included in the study will have a baseline visit and two evaluations visits at 3 and 6 months where cognitive performance (attention, executive functions, verbal memory, working memory and language) will be assessed using a brief neuropsychological battery; quality of life, using the WHOQol- AGE and EUROQOL-5D questionnaire; blood pressure; glycaemia; body composition, using an impedancemeter; and different markers of inflammation, interleukin (IL) 6, IL-1 and tumour necrosis factor alpha (TNF); and different markers of inflammation, interleukin (IL) 6, IL-1 and tumour necrosis factor alpha (TNF-α).

Participants will be randomised using the Epidat 4.0 programme into 2 groups (control group and intervention group) with a ratio of 1:1. Both groups will be instructed to continue with their usual dietary pattern without changing their habits during the study period.

Those in the control group will not receive any amount of raisins to their usual diet. The participants in the intervention group will receive 50 g of raisins and instructions on the time of day to take it (at night). The duration of this intervention will be 3 months. The daily nutritional intake of this amount of raisins is as follows: 146 kcal; 0.25 g of fat; 34 g carbohydrates of which 34 g sugars; 1.3 g protein; 1 g fibre. The total polyphenol content of total polyphenols from 50 g of raisinas is approximately 532,5 mg (phenols explorer database).

Study Overview

• Status: Completed
• Conditions: Cognitive Dysfunction
• Intervention / Treatment: Dietary supplement: Raisins

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Phase 3

Contacts and Locations

Study Locations

• Spain
  • Salamanca, Spain, 37005
    • José Ignacio Recio Rodriguez

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 70 years to 80 years (Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• People of both sexes aged between 70 and 80 years.
• The score on the Mini Mental State Examination (MMSE) must be greater than or equal to 24 points.
• Self-employed to attend the centre where the study is carried out.
• Signature of the informed consent form.

Exclusion Criteria:

• Coronary or cerebrovascular atherosclerotic pathology.
• Diabetes mellitus
• Grade II or higher heart failure.
• Moderate or severe chronic obstructive pulmonary disease.
• Advanced renal or hepatic disease.
• Severe mental illness.
• Oncological disease under treatment diagnosed within the last 5 years or terminal condition.
• Morbid obesity (IMC ≥ 40 kg/m2).
• Intolerance and/or allergy to any of the grape components.
• Any other circumstance at the criterion of the researchers.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control group; No intervention
Experimental: Experimental group; Supplementation of 50 g daily of rainsins for 3 months	Dietary supplement: Raisins; Daily supplementation of 50 g of rainsins for 3 months

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognitive impairment	Evaluated by Montreal Cognitive Assessment (MoCA). Score (0-30). 30 (better score)	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Health-related quality of life	Evaluated by EuroQoL-5D-3L (EuroQol Visual Analogue Scale (EQ-VAS)) Range 0-100. 100 (best quality of life)	3 months
Health-related quality of life	Evaluated by EuroQoL-5D-3L (EQ-5D summary index ) Range 0-1. 1 (best quality of life)	3 months
Health-related quality of life	Evaluated by WHOQOL-AGE. Total score Range 0-65. 65 (best quality of life)	3 months
Blood pressure	Measured in mmHg	3 months
Plasma cholesterol	Measured in mg/dL	3 months
Inflammatory marker (IL-6	Measured in pg/ml	3 months

Collaborators and Investigators

• Sponsor: University of Salamanca
• Investigators: Principal Investigator: Jose I Recio-Rodriguez, PhD, University of Salamanca

Study record dates

Study Major Dates

• Study Start (Actual): September 20, 2021
• Primary Completion (Actual): April 20, 2023
• Study Completion (Actual): May 20, 2023

Study Registration Dates

• First Submitted: July 1, 2021
• First Submitted That Met QC Criteria: July 16, 2021
• First Posted (Actual): July 19, 2021

Study Record Updates

• Last Update Posted (Estimated): December 19, 2023
• Last Update Submitted That Met QC Criteria: December 18, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Keywords: Clinical Trial; Polyphenols; Cognitive dysfunction; Heart Disease Risk Factors; Vitis
• Additional Relevant MeSH Terms: Mental Disorders; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction
• Other Study ID Numbers: GRS 2381/A/21

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
• product manufactured in and exported from the U.S.: No