Impact of Regular Consumption of Grape on Eye Health and Regulation of Advanced Glycation End-products in Singapore Older Adults
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 46
- 试验地点
- 2
- 主要终点
- Macular pigment optical density
研究概览
简要总结
The purpose of this study is to understand the impacts of regular consumption of freeze-dried table grape powder on eye health and regulation of advanced glycation end products in Singapore older adults. The investigators hypothesize that regular consumption of freeze-dried table grape powder will promote improvements in eye health and lower levels of advanced glycation end products when compared to the placebo group.
详细描述
The study will be a 16-week, double-blind, randomized, placebo-controlled trial using a parallel study design. 46 adults (aged 60 - 85) will be recruited and randomly assigned to the intervention or placebo group to investigate whether regular consumption of freeze-dried table grape powder (46g/d) can improve eye health parameters, blood/skin AGE and glycemic status, and reduce inflammation and oxidative stress. This study will consist of 1 screening visit and 5 study visits with 4-week intervals.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 60 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Male and female participants, aged between 60 and 85 years old inclusive
- •English-literate and able to give informed consent in English
排除标准
- •Allergy to grapes or food dyes/additives, or had serious food allergies in the past
- •Known eye diseases (macular degeneration, cataracts, retinopathy or glaucoma), blindness in at least one eye or have had eye surgery
- •Unable to view bright lights or flashing lights
- •Has Type 1 or 2 diabetes, uremia, cardiovascular disease, abnormal kidney and liver function
- •Taking eye medication and/or dietary supplements for the eyes for the past 3 month
- •Taking supplements containing carotenoids (e.g. Vitamin A, lutein, zeaxanthin) for past 3 months
- •Currently on a specialised 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
- •Currently on anti-hypertensive, cholesterol-lowering or psychoactive drugs
- •Scored ≤ 7 on the abbreviated mental test
- •Poor peripheral venous access based on past experiences with blood draw
- •Participating in another clinical study
结局指标
主要结局
Macular pigment optical density
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
A measurement of macular pigment of the eye using a heterochromatic flicker photometry device. The measurements are in arbitrary units.
Visual function questionnaire 25
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
A questionnaire to for participants to self-evaluate their perception of their current eye health based on general vision, ocular pain, near activities, distance activities, vision specific functions, driving, color vision and peripheral vision. The best possible score is 100 and worst possible score is 0.
Visual acuity
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
Participants will read out letters on a ETDRS LogMAR chart at a fixed distance where letters becomes smaller as it goes down the chart. Tests results will be recorded in number of letters read, where the more letters the better the outcome.
Skin advanced glycation end products levels
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
Measurement of skin advanced glycation end products level using a skin autofluorescence device, where participants wlll be instructed to place their forearm over the device and a light will be shone and a reading can be captured by detecting fluorescence. The results will be presented as arbitrary units.
Dietary advanced glycation end products level
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
Participants will be instructed to record down 3-day food records, from Thursday to Saturday, before each clinical visit. This will be used to estimate their advanced glycation end products intake from food by referring to existing nutrient databases. Units will be based on a common advanced glycation end product measured, carboxymethyllysine (CML), thus the unit will be mg CML/ kg food
Photostress recovery time
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
An ophthalmoscope will be used to shine a light into the participants eye for 10 seconds, and participants will be required to read letters off a chart the moment their vision returns to normal. The faster the recovery time, the better the outcome. Units will be in seconds
Blood advanced glycation end products levels
时间窗: Week 0, Week 8 and Week 16
Participants will have their blood drawn by medical professionals at the Occupational Health Clinic. The blood will be processed and stored. Measurements will be done using ultra-performance liquid chromatography coupled with mass spectrometry techniques to determine the levels of advanced glycation end products. Units will be in μg/mL.
Contrast sensitivity
时间窗: Week 0, Week 4, Week 8, Week 12, Week 16
Participants will read out letters on a ETDRS LogMAR chart at a fixed distance, where the letters differs in lightness to test participants' sensitivity to contrast. Tests results will be recorded in number of letters read, where the more letters the better the outcome.
次要结局
- Concentration of malondialdehyde(Week 0, Week 8, Week 16)
- Concentration of 8-isoprostaglandin-F2α(Week 0, Week 8, Week 16)
- Concentration of insulin(Week 0, Week 8, Week 16)
- Concentration of high-sensitivity C-reactive protein(Week 0, Week 8, Week 16)
- Percentage of glycated hemoglobin(Week 0, Week 8, Week 16)
- Concentration of interleukin-6(Week 0, Week 8, Week 16)
- Skin carotenoid status(Week 0, Week 4, Week 8, Week 12, Week 16;)
- Concentration of tumour necrosis factor-α(Week 0, Week 8, Week 16)
- Concentration of fasting blood glucose(Week 0, Week 8, Week 16)
研究者
Jung Eun Kim
Assistant Professor
National University of Singapore