EFFECTS OF LUTEIN IN RETINITIS PIGMENTOSA

视网膜色素变性是一组先天性视网膜变性，在美国影响超过10万人，其特征是夜盲，逐渐丧失周边视力，最终完全丧失视力。尽管进行了手术和医学上的努力，但仍不可能减缓RP的光感受器退化过程，更不用说逆转了。然而，最近一项由患者发起的初步研究表明，RP患者可能会对营养补充剂(叶黄素)做出反应，视力和中央视野区域有适度但在统计上显著的增加；这些效果严重依赖于频繁的家庭视力测试，使用个人电脑屏幕上的字母表和挂图来测量中心视野。支持数据可靠性的是眼睛颜色和视力变化之间的高度显著的相关性；眼睛颜色早些时候已经被证明影响补充叶黄素后黄斑色素的变化。在这个阶段，对叶黄素长期益处的研究将是昂贵的，而且如果没有安慰剂对照的试验数据，还为时过早。我们建议通过一项探索性研究，调查叶黄素的效果，并创建基于PC的家庭视力测试，为长期临床试验做准备。在研究的最初6个月，我们将开发和调整用于个人计算机的标准临床视力测试，并招募两个研究组：1)42名RP患者研究叶黄素对视力的影响，采用随机、双掩蔽交叉设计(拉丁方，3×16周)，使用安慰剂和2剂，每4-6周通过血清肝脏面板测试可能的不良反应，并通过基线和终值血清胡萝卜素测试以及频繁的黄斑色素密度测试来测量依从性；2)其他31名志愿者(10名正常视力，21名RP患者)，与第一组一起，每1-2周在家中使用基于PC的测试来监测他们的视力。结果将与多次访问我们中心期间进行的标准测试结果进行验证。这项研究产生的结果和工具将使长期叶黄素补充试验能够以视觉为主要结果衡量标准，该研究可以作为其他营养补充试验的模型。此外，根据作为这项研究的一部分开发的基于PC的家庭视力测试，未来的此类试验可能会在适当的保障下招募远程参与者，他们将下载测试软件，在家里进行频繁的结果测试，通过电子邮件提交测试结果，并由当地医生定期检查，以检测潜在的不良反应。

Retinitis pigmentosa (RP) is a group of congenital retinal degenerations affecting over 100,000 individuals in the US, characterized by nightblindness, gradual loss of peripheral vision, and eventually total vision loss. Despite surgical and medical efforts it has not been possible to slow down, let alone reverse, the process of photoreceptor degeneration in RP. However, a recent patient-initiated pilot study demonstrated that RP patients may respond to a nutrition supplement (lutein) with a modest, but statistically significant gain in visual acuity and central visual field area; demonstrating these effects relied critically on frequent home vision tests using a letter chart on the screen of a personal computer and a wall chart to measure the central visual field. Supporting the reliability of the data was a highly significant correlation between eye color and vision changes; eye color has earlier been shown to influence macular pigment changes following lutein supplementation. At this stage, a study of long-term lutein benefits would be costly and, without placebo-controlled pilot data, premature. We are proposing to prepare for a long-term clinical trial through an exploratory study, investigating the effects of lutein and creating PC-based home vision tests. In the initial 6 months of the study, we will develop and adapt standard clinical vision tests for use on a personal computer, and recruit two study groups: 1) 42 RP patients to study the effects of lutein on vision, using placebo and 2 dosages in a randomized, double- masked crossover design (Latin Square, 3 X 16 weeks), testing for possible adverse effects through serum hepatic panels every 4-6 weeks, and measuring compliance through baseline and end-value serum carotenoid tests and frequent macular pigment density tests; 2) 31 other volunteers (10 normally sighted, 21 RP patients) who, along with the first group, will monitor their vision every 1-2 weeks at home using the PC-based tests. Results will be validated against those obtained with standard tests during multiple visits to our center. The results and tools produced by this study will enable a long- term lutein supplementation trial with vision as its principal outcome measure, and the study can serve as a model for other nutritional supplement trials. Moreover, by virtue of the PC- based home vision tests developed as part of this study, such future trials may, under proper safeguards, enroll remote participants who would download test software, perform frequent outcome tests at home, submit test results via e-mail, and be examined periodically by local physicians to detect potential adverse effects.