The Effect of Lutein Supplementation in Preservation of Visual Function in Retinitis Pigmentosa; A Randomized Double–Blind Placebo–Controlled Clinical Trial
   

　　補充葉黃素對保存視網膜色素變性（RP）患者視力的效果：隨機、雙盲、對照臨床實驗
   

　　H. Bahrami, M. Melia, L. Yang, J. Stone, D. Bourdeau, F. Eshraghi, D. Malde novich and G. Dagnelie
   

　　Wilmer Eye Institute, Department of Ophthalmology, Johsn Hopkins　University, Baltimore, MD
   

　　Commercial Relationships: H. Bahrami, None; M. Melia, None; L. Yang, None; J. Stone, None; D. Bourdeau, None; F. Eshraghi, None; D. Maldenovich, None; G. Dagnelie, None.
   

　　Grant Identification: NEI Grant R03 EY 14416 and NCCAM Grant R21 AT00292
   

　　Abstract
   

　　摘要
   

　　Purpose: To evaluate the effectiveness of lutein supplementation in preventing progressive vision loss in patients with retinitis pigmentosa (RP) 
    目的：評估補充葉黃素對防止視網膜色素變性（RP）患者視力退行性喪失的效果
   

　　Methods: Started in May 2001, as a combined phase I/II trial, 45 adult patients with retinitis pigmentosa were enrolled in this cross–over trial and randomized to two groups. 
    方法：實驗從2001年5月開始，分I/II期，45名成年RP患者參加，隨機分成兩組。   
   

　　One group received lutein supplementation and for 24 weeks (0 mg/d/PO for 12wks followed by 30 mg/d/PO) and then placebo for 24 weeks, Washout Group. 
    一組服用葉黃素產品24周（0mg/d/PO 12周，接著30mg/d/PO），然后服用安慰劑24周，washout組。
   

　　In the other group, Buildup Group, placebo (24 weeks) was administered prior to lutein. 
    另外一組，Buildup組，先服用安慰劑（24周），然后服用葉黃素。
   

　　Subjects received multivitamin supplementation in addition to their lutein or placebo throughout the trial.
    整個實驗，受試者都補充符合維生素，不管是葉黃素還是安慰劑。
   

　　Subjects visual function was measured by multiple tests, including visual acuity, contrast sensitivity, and visual field at up to three levels of illumination at baseline and every 6 weeks in the lab.
    受試者的視功能綜合測試，包括視覺靈敏度、對比靈敏度、視野，在三級照明環境和每6周在實驗室測試。
   

　　Also, these tests were performed every week using a previously validated PC–based test in the home.
    同樣，每周在家里采用之前確認的，基于PC機的方法進行測試。
   

　　Results: Data from 35 subjects are reported here, and has been analyzed using the Generalized Estimating Equations (GEE) based on intention–to–treat analysis; 16 in the Washout Group, the other 19 in the Buildup Group.
    結果：35名受試者的結果如下，通過GEE分析治療目的，16名Washout組，19名Buildup組。
   

　　Analysis showed a significant beneficial effect of lutein on visual acuity (p<0.001), while contrast sensitivity was worsened significantly (p<0.001) during lutein usage; over the full trial period, though, contrast sensitivity among all subjects improved significantly.
    分析顯示葉黃素對視覺靈敏度有顯著效果（p<0.001），然而在葉黃素服用期間，對比靈敏度變得更差（p<0.001），整個實驗過后，所有受試者的對比靈敏度都顯著提高。
   

　　Lutein did not have a significant effect in preserving the visual field, but subjects in the Washout Group had significantly slower loss of visual field than those in the Buildup Group (p value: 0.02).
    葉黃素對視野損失效果不是十分明顯，但washout組的受試者明顯比Buildup組的受試者的視野喪失慢。
   

　　No adverse effects were observed for lutein, while one patient could not tolerate multivitamin.
    沒有發現葉黃素有不良作用，有一名患者不能忍受符合維生素。
   

　　Conclusions: Lutein appears to be an effective supplement for preservation of visual function in patients with retinitis pigmentosa, which is important in view of the lack of effective intervention for these patients.
    結論：補充葉黃素對保存RP 視功能是有效的，對這些患者來說，進行葉黃素干預是非常重要的。
   

　　Lutein appears to have differential effects on different components of vision loss in the same patients.
   葉黃素對相同患者的不同視力指標的效果不同。
  

　　The anomalous improvement of contrast sensitivity during washout may be attributed to a delayed incorporation and effect of lutein in the retina.
   對比靈敏度在washout期差異提高，可能是葉黃素在視網膜效果延遲的結果。
  

　　Since all subjects were receiving multivitamin throughout the trial, preservation of visual function may in part be attributed to multivitamin, or its combination with lutein. 
    由于在整個實驗過程當中，所有受試者都服用了復合維生素，保存視功能可能也跟復合維生素有關，或者復合了葉黃素。
   

　　Long–term lutein and multivitamin effects on vision in RP patients need to be further investigated.
    長期的葉黃素和復合維生素對RP患者的視力作用需要進一步研究。
   

　　Key Words: retinitis • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • low vision.