Abstract
Purpose: :
To evaluate the efficacy and safety of oral DHA in preventing the occurrence of choroidal neovascularization (CNV) in Age-related Macular Degeneration (AMD) over 3 years.
Methods: :
The NAT-2 (Nutritional AMD Treatment-2) study is a double-masked, single-centre, randomized, parallel, comparative trial in patients (pts) with early AMD (drusen, no CNV) in the study eye and neovascular AMD in the fellow eye, receiving oral DHA (840 mg/d) or Placebo (PBO, olive oil). Primary Study End Point (SEP): time to occurrence of CNV in the study eye. Secondary efficacy SEP in study eye are: percentage of subjects developing CNV, changes in visual acuity (VA) and function, occurrence and progression of drusen and DHA in red-blood-cell membranes (RBCM) .
Results: :
Among 263 Caucasian AMD pts (Full Set Analysis, 134:DHA and 129:PBO), 170 (65%) were women; 24.3% had AMD family history and 77% were never-smokers. They were aged 71y at diagnosis and 74y at entry; mean BMI was 26. At baseline, mean BCVA was 0.13 LogMAR in the study eye, cataract was found in 162 (62%), ≥5 large drusen in 258 (98%), and at least 1 soft drusen or pigmentary changes in 205 (78%) pts. At 3-y follow-up, at least 78% pts were compliant as assessed by a median +88% increase in serum DHA, in the DHA-allocated group vs -7% (PBO). In the study eye, mean time to CNV occurrence was similar in both groups: 19.5mo (DHA) vs 18.7mo (PBO) over 3y. Yearly rate of CNV occurrence progressed similarly in both groups from 9% (1-y) to 13% (3-y), with an overall 27% event rate. At 3y, BCVA in the study eye was similar in both groups: 0.29 (DHA) vs 0.24 (PBO) LogMAR, with 18% (DHA) and 14% (PBO) showing >15 letters decrease at 3y. Number, size and type of drusen progressed similarly in DHA and PBO groups. A strong median DHA increase in RBCM was observed from baseline in the DHA group: +60% (DHA) vs +4% (PBO), p<0.001. In this elderly population, adverse events (AE) rate was related to advanced-age morbidity; most of the ocular AE were mainly a result of AMD and cataract progression in both eyes.
Conclusions: :
CNV progression was not reduced in patients with advanced AMD receiving oral DHA over 3y. Subgroup analysis may give more information about a potential role of DHA in prevention of exudative AMD.
Clinical Trial: :
http://www.isrctn.org ISRCTN98246501
Keywords: age-related macular degeneration • nutritional factors • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials