Lutein/Zeaxanthin and Omega-3 Supplementation in Persons Over Age 60
Status:
Completed
Trial end date:
2007-08-15
Target enrollment:
Participant gender:
Summary
This study will explore whether taking the vitamins lutein and zeaxanthin, with or without
Omega-3 fatty acid (fish oil or docosahexanoic acid, also known as DHA) will change the
amount of lutein and zeaxanthin in the blood among people with age-related macular
degeneration (AMD). AMD is one of the leading causes of legal blindness among people over the
age of 50 in developed countries. In the disease, the retina of the eye, the sensory portion,
worsens in condition. AMD causes progressive loss of central vision, with only peripheral
vision remaining, that is, the ability for someone to see from the edges of the eye. To date,
there is not any effective treatment to improve vision for most people whose AMD is advanced.
Yet some data from research studies suggest a possible role of antioxidants, including
lutein, in reducing the risk of AMD and cataracts. Lutein and zeaxanthin belong to the
carotenoid family of vitamins, of which there are more than 600. There are 40 or 50
carotenoids in the typical diet of human beings, but only 14 major dietary ones are
identified in human plasma. Lutein, in particular, is a vitamin that is found naturally in
the retina, especially in the macula, the region of the eye that is essential for fine,
detailed vision. Previous studies have shown that higher levels of foods rich in Omega-3
fatty acid were associated with a lower likelihood of AMD.
Patients ages 60 and older who may or may not have AMD, who do not have certain other serious
eye disorders, and who have not had potentially life-threatening illness in the last year may
be eligible for this study. About 40 people will participate.
Patients will undergo a medical history and physical examination. A blood collection of about
4 tablespoons will be done to measure the amount of lutein and other vitamins in the blood.
Patients will have a complete eye examination consisting of procedures standard to those
given by ophthalmologists. Participants will have photographs taken of their eyes, and they
will undergo a visual field test. Flicker photometry also will be conducted. This consists of
the patients looking at a flashing bluish light with one eye at a time, and turning a knob
until the light stops flashing. Then during the test, patients will look away from the light
and turn the knob until the flashing stops.
During this study study, patients will be asked to not take more than two tablets each day of
multivitamins that contain lutein. The vitamin supplements will be provided as pills that
represent one of two vitamin regimens given on a random basis: either lutein and zeaxanthin
with DHA or lutein and zeaxanthin without DHA added. The amounts would be 10 mg/day of lutein
and 2 mg/day of zeaxanthin, with or without 1 g/day of DHA. Patients will return to the study
center for follow-up visits at 1 month, 3 months, 6 months, and 9 months. During those
visits, some of the examinations done earlier will be repeated so that the researchers can
evaluate the effects of supplements on patients' eyes. Patients will also be watched for
possible side effects from the vitamins supplements. Lutein and zeaxanthin supplements are
considered to be safe with possible minor side effects, such as headaches and difficulty in
swallowing the tablets. Fish oil or DHA supplements may also cause abdominal discomfort.
If information obtained from this study may be important for participants' health, they will
be informed when it is available. There are no plans to give participants the results of any
medical tests, evaluations, or other research data. Further research may be necessary before
such results become meaningful.