Impact of Regular Consumption of Grapes on Eye Health in Singapore Older Adults

NCT ID: NCT05064865

Last Updated: 2023-11-09

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 34 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-01-28
• Study Completion Date: 2024-10-31

Brief Summary

Aging epidemics in Singapore are rapidly increasing and Age-related macular degeneration (AMD) prevalence is significantly associated with older age. This study aims to understand the effect of consuming freeze-dried table grape powder on AMD in an older population.

Detailed Description

This will be carried out through a 16-week double-blind, randomized, placebo-controlled trial of parallel study design. Thirty-eight men and women (aged between 60 and 85 years old inclusive) will recruited and assigned to an intervention or placebo group. The intervention group will consume 46 g/day of a freeze-dried table grape and the control group will consume the same amount of a placebo, table grape placebo powder. Measurements of 1) macular pigment optical density (MPOD), a clinical marker for eye health, 2) carotenoids status, 3) markers of oxidative stress, 4) markers of endothelial function, 5) body size and blood pressure, and 6) dietary assessment will be assessed over the 16-week study. This study will consist of 1 screening visit and 5 study visits in 4-week intervals to the Food Science and Technology Department, Occupational Health Clinic and National University Heart Centre.

Conditions

Eye Health; Age-related Macular Degeneration

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: DOUBLE

Study Groups

Freeze-dried table grape powder

The intervention group will consume 46 g/day of a freeze-dried table grape powder.

Group Type: EXPERIMENTAL

Freeze-dried table grape powder

Intervention Type: DIETARY_SUPPLEMENT

Consumption of 46g/day freeze-dried table grape powder

Placebo grape powder

The control group will consume the same amount of a placebo with a similar taste to the table grape powder.

Group Type: PLACEBO_COMPARATOR

Placebo of the table grape powder

Intervention Type: DIETARY_SUPPLEMENT

Consumption of 46g/day placebo version of the freeze-dried table grape powder

Interventions

Freeze-dried table grape powder

Consumption of 46g/day freeze-dried table grape powder

Intervention Type: DIETARY_SUPPLEMENT

Placebo of the table grape powder

Consumption of 46g/day placebo version of the freeze-dried table grape powder

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• Male and female participants, aged between 60 and 85 years old inclusive
• Able to give informed consent in English

Exclusion Criteria

• Smokers
• Allergy to grapes
• Known eye diseases (macular degeneration, cataracts, retinopathy or glaucoma), blindness in at least one eye or have had eye surgery
• Abnormal kidney and liver function
• Taking eye medication and/or dietary supplements for the eyes for the past 3 months
• Taking supplements containing carotenoids (e.g. Vitamin A, lutein, zeaxanthin) for the past 3 months
• Currently on type 2 diabetic medication.
• Currently on anti-hypertensive or cholesterol-lowering; unless this prescription has been ongoing for more than 3 years prior to study participation.
• Currently on a specialized diet (e.g. vegetarian, vegan, weight loss diet, low fat diet)
• Consumes more than 2 alcoholic drinks per day i.e. one drink is defined as either 150ml of wine, 340ml of beer/cider or 45ml of distilled spirit.
• Significant change in weight (≥ 3 kg body weight) in the past 3 months
• Significant exercise pattern over the past 3 months defined as high-intensity exercise of more than 3 hours per week
• Poor peripheral venous access based on past experiences with blood draw
• Participating in another clinical study

• Minimum Eligible Age: 60 Years
• Maximum Eligible Age: 85 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National University Hospital, Singapore

OTHER

Sponsor Role: collaborator

Ministry of Education, Singapore

OTHER_GOV

Sponsor Role: collaborator

National University of Singapore

OTHER

Sponsor Role: lead

Responsible Party

Jung Eun Kim

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Jung Eun Kim

Role: PRINCIPAL_INVESTIGATOR

National University of Singapore

Locations

National University of Singapore

Singapore, , Singapore

Countries

Singapore

References

Gehrs KM, Anderson DH, Johnson LV, Hageman GS. Age-related macular degeneration--emerging pathogenetic and therapeutic concepts. Ann Med. 2006;38(7):450-71. doi: 10.1080/07853890600946724.

Reference Type: BACKGROUND

PMID: 17101537 (View on PubMed)

Hu W, Zheng R, Feng Y, Tan D, Chan Chung-Tsing G, Su X, Kim JE. Impacts of regular consumption of grapes on macular pigment accumulation in Singapore older adults: a randomized controlled trial. Food Funct. 2023 Sep 19;14(18):8321-8330. doi: 10.1039/d3fo02105j.

Reference Type: DERIVED

PMID: 37605542 (View on PubMed)

Other Identifiers

S15

Identifier Type: -

Identifier Source: org_study_id