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Arch Ophthalmol. 2004 Sep;122(9):1306-14.Click here to read Links
Further evaluation of docosahexaenoic acid in patients with retinitis pigmentosa receiving vitamin A treatment: subgroup
analyses.
* Berson EL,
* Rosner B,
* Sandberg MA,
* Weigel-DiFranco C,
* Moser A,
* Brockhurst RJ,
* Hayes KC,
* Johnson CA,
* Anderson EJ,
* Gaudio AR,
* Willett WC,
* Schaefer EJ.
Berman-Gund Laboratory for the Study of Retinal Degenerations, Harvard Medical School, 243 Charles Street, Boston,
MA 02114, USA.
OBJECTIVE: To determine whether docosahexaenoic acid will slow the course of retinal degeneration in subgroups of
patients with retinitis pigmentosa who are receiving vitamin A. DESIGN: A cohort of 208 patients with retinitis pigmentosa,
aged 18 to 55 years, were randomly assigned to 1200 mg of docosahexaenoic acid plus 15 000 IU/d of vitamin A given as retinyl
palmitate (DHA + A group) or control fatty acid plus 15 000 IU/d of vitamin A (control + A group) and followed up over 4 years.
Seventy percent of the patients in each group were taking vitamin A, 15 000 IU/d, prior to entry. We compared rates of decline
in ocular function in the DHA + A vs control + A groups among the subgroups defined by use or nonuse of vitamin A prior to
entry. We also determined whether decline in ocular function was related to red blood cell phosphatidylethanolamine docosahexaenoic
acid level, dietary omega-3 fatty acid intake, or duration of vitamin A use. Main outcome measures were Humphrey Field Analyzer
visual field sensitivity, 30-Hz electroretinogram amplitude, and visual acuity. RESULTS: Among patients not taking vitamin
A prior to entry, those in the DHA + A group had a slower decline in field sensitivity and electroretinogram amplitude than
those in the control + A group over the first 2 years (P =.01 and P =.03, respectively); these differences were not observed
in years 3 and 4 of follow-up or among patients taking vitamin A prior to entry. In the entire cohort, red blood cell phosphatidylethanolamine
docosahexaenoic acid level was inversely related to rate of decline in total field sensitivity over 4 years (test for trend,
P =.05). This was particularly evident over the first 2 years among those not on vitamin A prior to entry (test for trend,
P =.003). In the entire control + A group, dietary omega-3 fatty acid intake was inversely related to loss of total field
sensitivity over 4 years (intake, <0.20 vs > or =0.20 g/d; P =.02). The duration of vitamin A supplementation prior
to entry was inversely related to rate of decline in electroretinogram amplitude (P =.008). CONCLUSIONS: For patients with
retinitis pigmentosa beginning vitamin A therapy, addition of docosahexaenoic acid, 1200 mg/d, slowed the course of disease
for 2 years. Among patients on vitamin A for at least 2 years, a diet rich in omega-3 fatty acids (> or =0.20 g/d) slowed
the decline in visual field sensitivity.
PMID: 15364709 [PubMed - indexed for MEDLINE]
Am J Ophthalmol. 2004 Apr;137(4):704-18.Click here to read Links
A randomized, placebo-controlled clinical trial of docosahexaenoic acid supplementation for X-linked retinitis pigmentosa.
* Hoffman DR,
* Locke KG,
* Wheaton DH,
* Fish GE,
* Spencer R,
* Birch DG.
Retina Foundation of the Southwest, Dallas, Texas 75231, USA. dhoffman@retinafoundation.org
PURPOSE: Low docosahexaenoic acid (DHA) in X-linked retinitis pigmentosa (XLRP) may influence retinal function. The
goals of this study were to elevate blood DHA levels and determine the effect on the rate of disease progression. DESIGN:
In a 4-year prospective randomized clinical trial, male patients with XLRP (mean age = 16 years; range = 4-38 years) received
DHA (400 mg/d; n = 23; +DHA group) or placebo (n = 21) capsules. METHODS: Red blood cell (RBC)-DHA concentrations were assessed
every 6 months. Full-field cone electroretinograms (ERGs; the primary outcome measure), visual acuity, dark-adaptation, visual
fields, rod ERGs, and fundus photos were recorded annually. RESULTS: In the +DHA group, RBC-DHA increased 2.5-fold over placebo
levels (70 vs 28 mg DHA/l). Repeated measures analysis of variance for cone ERG showed a significant main effect of year (P
<.0001) but not of group (P =.16). Preservation of cone ERG function correlated with RBC-DHA (P =.018), and there was less
change in fundus appearance in the +DHA group (P =.04). Neither visual acuity nor visual fields were changed. In subset analysis,
DHA supplementation was beneficial in reducing rod ERG functional loss in patients aged <12 years (P =.040) and preserving
cone ERG function in patients > or =12 years (P =.038). CONCLUSIONS: Although DHA-supplemented patients had significantly
elevated mean RBC-DHA levels, the rate of cone ERG functional loss was not significantly different between groups. Supplemental
analyses provided evidence for a DHA benefit and a direction for subsequent investigations.
PMID: 15059710 [PubMed - indexed for MEDLINE]
Clin Ter. 2004 Jul-Aug;155(7-8):347-51. Links
[Diet and management of degenerative diseases of the retina (retinitis pigmentosa)]
[Article in Italian]
* Miggiano GA,
* Falsini B.
Centro di Ricerca in Nutrizione Umana, Istituto di Biochimica Clinica, Italia.
Considerable progress has been made in the understanding and management of degenerative diseases of the retina. The
dietetic intervention has been favourably proposed in the most common forms of retinitis pigmentosa, a condition potentially
leading to blindness. Vitamin A has been shown to be effective in delaying progression of the disease. In these patients such
treatment is the only possible therapy, to date, and a lifetime generous supplementation of retinol is advisable, together
with a vitamin A-rich diet and/or a dietary supplement (e.g. carrot flour) or pharmacologic supplement of vitamin A. Supply
of vitamin A in doses up to 25000 IU (7500 igr/day), even for several years, has so far proved safe from risk of occurrence
of liver disease. A possible effect on hypercholesterolemia related to a very prolonged treatment in predisposed individuals
can be avoided by using a special diet, particularly enriched with beta-carotene. Guidelines for preparing a diet, specially
formulated to provide an elevated weekly supply of vitamin and/or its precursor (equal to 15000 IU or 5000 microg of RE, retinol
equivalent) and to control possible risk factors related to dietetic manipulation (supply of fat lower than 30% of total calories,
variable levels of cholesterol and polyunsaturated fatty acids n-3, n-6) are presented. As long as resolutive therapy is lacking,
dietetic intervention plays a primary role, although underestimated, in the management of the patients suffering from retinitis
pigmentosa. The diet is specifically characterized by presence of food with a high content of carotenoids, substances with
a favourable and additive effect.
PMID: 15553263 [PubMed - indexed for MEDLINE]
Metab Brain Dis. 2002 Sep;17(3):183-97. Related Articles, Links
Treatment with taurine, diltiazem, and vitamin E retards the progressive visual field reduction in retinitis pigmentosa:
a 3-year follow-up study.
Pasantes-Morales H, Quiroz H, Quesada O.
Institute of Cell Physiology, National University of Mexico, Mexico City. hpasante@ifisol.unam.mx
The purpose of this study to assess the effect of the formula taurine/diltiazem/vitamin E on the progression of visual
field loss in retinitis pigmentosa. A double blind, placebo controlled study in 62 patients: visual field threshold values
were obtained in a Humphrey Field Analyzer from center (30 degrees) and periphery (30-60 degrees), every 4 months during 3-year
follow-up. Data were analyzed by univariate regression, with slopes obtained from the best fit lines. Based on slope values,
three groups of patients were identified as those showing negative, positive, or zero slope: > or = 1 to < or = +1.
In controls (32 patients), at central area, the distribution in negative, zero, or positive slope was, respectively, 16 (50%),
11 (35%), and 5 (15%). In the treated group (30 patients) this distribution was 6 (20%) negative, 17 (53%) zero, and 7 (23%)
positive slope. In periphery, 16 control patients were distributed as 11 (69%) negative, 4 (25%) zero, and 1 (6%) positive
slope. In the treated group (17 patients), the distribution was opposite: 1 (6%) negative, 7 (41%) zero, and 9 (53%) positive
slope. Nineteen patients receiving treatment up to 6 years showed similar distribution by slope values. Eight out of 9 patients
switched from placebo (2 years) to treatment (2-3 years), showed improving changes in their slope values. A beneficial effect
of the treatment decreasing the rate of visual field loss was observed, likely through a protective action from free radical
reactions in affected photoreceptors.
Publication Types:
Clinical Trial
Randomized Controlled Trial
PMID: 12322788 [PubMed - indexed for MEDLINE]
Arch Ophthalmol. 1993 Jun;111(6):761-72. Related Articles, Links
Comment in:
Arch Ophthalmol. 1993 Jun;111(6):751-4.
Arch Ophthalmol. 1993 Nov;111(11):1460-1; discussion 1463-5.
Arch Ophthalmol. 1993 Nov;111(11):1460; discussion 1463-5.
Arch Ophthalmol. 1993 Nov;111(11):1461-2; discussion 1462-5.
Arch Ophthalmol. 1993 Nov;111(11):1462-3.
Arch Ophthalmol. 1993 Nov;111(11):1463; discussion 1463-6.
A randomized trial of vitamin A and vitamin E supplementation for retinitis pigmentosa.
Berson EL, Rosner B, Sandberg MA, Hayes KC, Nicholson BW, Weigel-DiFranco C, Willett W.
Berman-Gund Laboratory for the Study of Retinal Degenerations, Harvard Medical School, Massachusetts Eye and Ear Infirmary,
Boston 02114.
OBJECTIVE--To determine whether supplements of vitamin A or vitamin E alone or in combination affect the course of retinitis
pigmentosa. DESIGN--Randomized, controlled, double-masked trial with 2 x 2 factorial design and duration of 4 to 6 years.
Electroretinograms, visual field area, and visual acuity were measured annually. SETTING--Clinical research facility. PATIENTS--601
patients aged 18 through 49 years with retinitis pigmentosa meeting preset eligibility criteria. Ninety-five percent of the
patients completed the study. There were no adverse reactions. INTERVENTION--Patients were assigned to one of four treatment
groups receiving 15,000 IU/d of vitamin A, 15,000 IU/d of vitamin A plus 400 IU/d of vitamin E, trace amounts of both vitamins,
or 400 IU/d of vitamin E. MAIN OUTCOME MEASURE--Cone electroretinogram amplitude. RESULTS--The two groups receiving 15,000
IU/d of vitamin A had on average a slower rate of decline of retinal function than the two groups not receiving this dosage
(P = .01). Among 354 patients with higher initial amplitudes, the two groups receiving 15,000 IU/d of vitamin A were 32% less
likely to have a decline in amplitude of 50% or more from baseline in a given year than those not receiving this dosage (P
= .01), while the two groups receiving 400 IU/d of vitamin E were 42% more likely to have a decline in amplitude of 50% or
more from baseline than those not receiving this dosage (P = .03). While not statistically significant, similar trends were
observed for rates of decline of visual field area. Visual acuity declined about 1 letter per year in all groups. CONCLUSIONS--These
results support a beneficial effect of 15,000 IU/d of vitamin A and suggest an adverse effect of 400 IU/d of vitamin E on
the course of retinitis pigmentosa.
Publication Types:
Clinical Trial
Randomized Controlled Trial
PMID: 8512476 [PubMed - indexed for MEDLINE]
Altern Med Rev. 1999 Oct;4(5):342-59. Related Articles, Links
Natural therapies for ocular disorders, part one: diseases of the retina.
Head KA.
Diseases of the retina are the leading causes of blindness throughout the world. Evidence points to potential benefit
from nutritional and botanical interventions for the prevention and treatment of several of these conditions, including macular
degeneration, diabetic retinopathy, retinopathy of the newborn, and retinitis pigmentosa. Epidemiological evidence points
to the potential of antioxidant vitamins E and C, carotenoids, zinc, and selenium in the prevention and possible treatment
of macular degeneration. In addition, dietary components such as red wine-high in important flavonoids-and fruits and vegetables
high in carotenoids appear to offer some protection. While diabetic retinopathy can best be prevented by maintaining good
blood sugar control, there are a number of nutrients and botanicals which may help prevent and treat retinopathy by inhibiting
protein glycosylation, stabilizing collagen, decreasing capillary permeability, and providing important antioxidant effects.
Extensive research on the use of vitamin E for the prevention of retrolental fibroplasia (retinopathy of the newborn), despite
yielding promising results, has not resulted in incorporation of vitamin E into conventional standards of care protocols.
Retinitis pigmentosa resembles the retinal damage seen in taurine-deficient cats. While patients with retinitis pigmentosa
do not appear to be deficient in taurine, they appear to have faulty cellular uptake of this important amino acid. Disturbed
utilization of vitamin A also appears to play a part in retinitis pigmentosa, and a subgroup of patients benefit from supplementation.
Publication Types:
Review
Review, Tutorial
PMID: 10559549 [PubMed - indexed for MEDLINE]
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