Macular Pigment and Glare Disability

Study Overview
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Brief Summary
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The purpose of this study is: I. To measure MP optical density (MPOD) in two groups (experimental and placebo) of 50 subjects each (N = 100), during an Lutein + Zeaxanthin supplementation period of 12 months. II. To test the hypothesis that increases in MP (via 12 mg daily Lutein + Zeaxanthin supplementation) will result in significantly improved visual performance under disability glare conditions. III. To test the hypothesis that increases in MP (via 12 mg daily L + Z supplementation) will result in significantly reduced photostress recovery times. IV. To test the hypothesis that increases in MP (via 12 mg daily L + Z supplementation) will result in improved contrast enhancement.

Detailed Description
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The following measurements will be taken, before and after supplementation with lutein and zeaxanthin: Macular pigment optical density (MPOD) Visual performance under glare conditions Photostress recovery times chromatic contrast sensitivity.

Official Title
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Effects of Lutein and Zeaxanthin Upon MPOD and Its Effects Upon Glare Disability, Photostress Recovery, and Contrast Enhancement in Healthy Subjects: A Randomized, Double-blind Placebo-controlled Study

Conditions
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Vision, Entoptic

Intervention / Treatment
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* Dietary Supplement: 12 mg Lutein + Zeaxanthin
* Dietary Supplement: Visually identical placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Gender: male or female Age: 18 - 40 years BMI: 20-30 No anticipated changes in dieting habits (as relevant to xanthophyll intake). No anticipated surgical procedures. Assessed as healthy, based on a pre-study examination including medical history, physical examination, and clinical laboratory. The examination will be performed by an MD or a Nurse Practitioner. Willingness and ability to give written informed consent and willingness and ability to comply with the study requirements. Corrected visual acuity (ETDRS): better than 20/60 Exclusion Criteria: BMI <20 or >30 Age <18 or >40 years Smokers Current or history of relevant diseases (such as AMD) Corrected visual acuity worse than 20/60 Inability to reliably perform MPOD measurements by heterochromatic flicker photometry or any of the other ophthalmic tests of the study. Any condition likely to interfere with normal gastro-intestinal absorption of xanthophylls. Current use of xanthophyll containing supplements Use of xanthophyll containing supplements in the past 6 months Participation in any other study during last 1 month. Blood donation during the last 3 months. Known hypersensitivity or allergy to xanthophylls. Regular intake of medications or supplements, which the principal investigator deems likely to confound the study outcomes. Suspected lack of compliance with any requirements of the study. Childbearing potential and unwillingness to refrain from acceptable anticonceptive measures (not including abstinence). Current pregnancy or breast feeding Any relevant abnormalities in the routine laboratory tests

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Two arms: nutritional supplement vs. placebo.
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Intervention<br>10 mg FloraGlo lutein + 2 mg Optisharp zeaxanthin | Dietary Supplement: 12 mg Lutein + Zeaxanthin<br>* 10 mg FloraGlo lutein + 2 mg Optisharp zeaxanthin, taken once daily for one year<br>* Other names: FloraGlo lutein + OptiSharp zeaxanthin;|
| Placebo Comparator: Placebo<br>visually identical placebo | Dietary Supplement: Visually identical placebo<br>* Visually identical placebo, taken once daily for one year<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Macular Pigment Optical Density | optical density of macular pigment layer of the neural retina at 30-minutes of retinal eccentricity | every three months for one year; 12-month measure reported. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glare Disability | light energy needed to obscure or veil a visual target; calculated as log-relative energy, which is the physical energy needed for the subject to report that the visual target has been veiled, given the intensity of the target, logged. | 12-month data point only | 
| Photostress Recovery Time | amount of time needed to recover from exposure to a bright light, and to regain sight of a visual target | improvement in recovery time; baseline recovery time (sec) minus 12-month recovery time (sec) | 
| Heterochromatic Contrast Sensitivity | amount of short-wave light energy necessary to obscure of veil a visual target, calculated as log-relative energy, which is the physical energy needed for the subject to report that the visual target has been veiled, given the intensity of the target, logged. | 12-month data point only | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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macular pigment, glare disability, lutein, photostress, chromatic contrast sensitivity