Mayer-Davis E J, Bell R A, Reboussin B A, Rushing J, Marshall J A, Hamman R F
Department of Epidemiology and Biostatistics, School of Public Health, University of South Carolina, Columbia 29208, USA.
Ophthalmology. 1998 Dec;105(12):2264-70. doi: 10.1016/S0161-6420(98)91227-1.
Diabetic retinopathy (DR) is a major cause of visual impairment and blindness in adults. Antioxidant nutrients, such as vitamins C and E and beta-carotene, may be protective of some eye disorders, such as cataract and age-related macular degeneration, but a relationship between these nutrients and DR has yet to be defined. The purpose of this study was to examine the relation between dietary and supplement intakes of vitamins C, E, and beta-carotene and the risk of DR.
Both cross-sectional and longitudinal data were collected from participants in the San Luis Valley Diabetes Study, including non-Hispanic white and Hispanic adults in southern Colorado.
A total of 387 participants with type 2 diabetes completed at least 1 complete retinal examination and 24-hour dietary recall (including vitamin supplement use).
Type 2 diabetes was defined according to World Health Organization criteria. DR was assessed by retinal photographs, using the Airlie House criteria to classify DR as none, background, preproliferative, or proliferative. Data for both eyes, from up to three clinic visits per participant, were used for analysis. Ordinal logistic regression analysis was used, taking advantage of multiple clinic visits by individual participants and observations from both eyes, to assess the risk for increased DR severity over time as a function of changes in intake of vitamin C, vitamin E, and beta-carotene. Six categories of intake for each nutrient (first to fourth quintiles and ninth and tenth deciles) were considered to ascertain any potential threshold effect. Analyses accounted for age, duration of diabetes, insulin use, ethnicity, glycated hemoglobin, hypertension, gender, and caloric intake.
An increase over time in vitamin C intake from the first to ninth deciles was associated with a risk for increased severity of DR (odds ratio = 2.21, P = 0.01), although excess risk was not observed for the tenth decile or the second through fourth quintiles compared to the first quintile. Increased intake of vitamin E was associated with increased severity of DR among those not taking insulin (odds ratios = 2.69, 2.59, 3.33, 5.65, 3.79; P < 0.02, for an increase over time from the first to the second through fourth quintiles and ninth and tenth deciles, respectively). Among those taking insulin, increased intake of beta-carotene was associated with a risk for severity of DR (odds ratio = 3.31, P = 0.003, and 2.99, P = 0.002, respectively, for the ninth and tenth deciles compared to the first quintile).
No protective effect was observed between antioxidant nutrients and DR. Depending on insulin use, there appeared to be a potential for deleterious effects of nutrient antioxidants. Further research is needed to confirm associations of nutrient antioxidant intake and DR.
糖尿病视网膜病变（DR）是成年人视力损害和失明的主要原因。抗氧化营养素，如维生素C、维生素E和β-胡萝卜素，可能对某些眼部疾病具有保护作用，如白内障和年龄相关性黄斑变性，但这些营养素与DR之间的关系尚未明确。本研究的目的是探讨维生素C、维生素E和β-胡萝卜素的饮食和补充剂摄入量与DR风险之间的关系。
从圣路易斯谷糖尿病研究的参与者中收集横断面和纵向数据，该研究包括科罗拉多州南部的非西班牙裔白人和西班牙裔成年人。
共有387名2型糖尿病患者完成了至少1次完整的视网膜检查和24小时饮食回顾（包括维生素补充剂使用情况）。
2型糖尿病根据世界卫生组织标准定义。通过视网膜照片评估DR，使用艾利屋标准将DR分为无、背景性、增殖前期或增殖性。每位参与者最多三次门诊就诊时双眼的数据用于分析。采用有序逻辑回归分析，利用个体参与者的多次门诊就诊情况和双眼的观察结果，评估随着时间推移DR严重程度增加的风险与维生素C、维生素E和β-胡萝卜素摄入量变化之间的函数关系。考虑每种营养素的六类摄入量（第一至第四五分位数以及第九和第十十分位数），以确定是否存在任何潜在的阈值效应。分析考虑了年龄、糖尿病病程、胰岛素使用情况、种族、糖化血红蛋白、高血压、性别和热量摄入。
从第一十分位数到第九十分位数，维生素C摄入量随时间增加与DR严重程度增加的风险相关（优势比 = 2.21，P = 0.01），尽管与第一五分位数相比，第十十分位数或第二至第四五分位数未观察到额外风险。在未使用胰岛素的人群中，维生素E摄入量增加与DR严重程度增加相关（优势比分别为2.69、2.59、3.33、5.65、3.79；P < 0.02，分别表示从第一到第二至第四五分位数以及第九和第十十分位数随时间增加）。在使用胰岛素的人群中，β-胡萝卜素摄入量增加与DR严重程度的风险相关（与第一五分位数相比，第九和第十十分位数的优势比分别为3.31，P = 0.003和2.99，P = 0.002）。
未观察到抗氧化营养素与DR之间的保护作用。根据胰岛素使用情况，营养抗氧化剂似乎有可能产生有害影响。需要进一步研究来证实营养抗氧化剂摄入量与DR之间的关联。
