Ignite Creation Date:
2024-05-05 @ 9:35 AM
Last Modification Date:
2024-10-26 @ 9:01 AM
Study NCT ID:
NCT00000152
Status:
UNKNOWN
Last Update Posted:
2005-06-24
First Post:
1999-09-23
Brief Title:
Randomized Trial of Beta-Carotene and Macular Degeneration
Sponsor:
National Eye Institute NEI
Organization:
National Eye Institute NEI
Study Overview
Official Title:
None
Status:
UNKNOWN
Status Verified Date:
2001-09
Last Known Status:
ACTIVE_NOT_RECRUITING
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
To determine whether 50 mg of beta-carotene taken every other day reduces the risk of developing age-related macular degeneration AMD among male US physicians who were aged 40 to 84 in 1982
To investigate the possible relationship of AMD with other antioxidants including selenium and vitamins A C and E
To identify potential risk factors for development of AMD Possible risk factors include height systemic hypertension cardiovascular disease blood cholesterol cigarette smoking iris and skin color sunlight exposure body mass index diabetes and alcohol intake
To investigate the possible relationship of AMD with other antioxidants including selenium and vitamins A C and E
To identify potential risk factors for development of AMD Possible risk factors include height systemic hypertension cardiovascular disease blood cholesterol cigarette smoking iris and skin color sunlight exposure body mass index diabetes and alcohol intake
Detailed Description:
Macular degeneration a major cause of blindness in the United States is the leading cause of new cases of blindness in people aged 65 and older The National Eye Institute estimates that each year an additional 165000 people mainly in the older age groups develop macular disease Among all people with macular degeneration approximately 116000 are affected by the neovascular form of the disease Although laser treatment is an effective treatment for patients with certain forms of neovascular membranes exudative AMD for most patients there is no available treatment
The pathogenesis of AMD is only partly understood and its etiology remains obscure The Retinal and Choroidal Diseases Panel of the National Advisory Eye Council has stated that none of the fundamental causes of any type of macular disease is known and none can be prevented Thus this panel recommended that one of the NEIs program development priorities should be to initiate epidemiologic studies of macular diseases to identify possible causative protective or aggravating factors
This trial is part of the Physicians Health Study sponsored by the National Heart Lung and Blood Institute NHLBI of the National Institutes of Health with funding for eye epidemiologic data evaluations provided by the NEI It is an ongoing randomized placebo-controlled trial of aspirin in the prevention of cardiovascular mortality and of beta-carotene in the prevention of cancer Following randomization each of the 22071 physicians enrolled was assigned to one of four groups to take either aspirin or its placebo and beta-carotene or its placebo Followup questionnaires are sent 6 and 12 months after randomization and every 12 months thereafter The average length of followup is now greater than 12 years
The hypothesis that beta-carotene levels are inversely related to AMD is supported by experimental studies on the relationship between antioxidants and retinal morphology and function There is increasing evidence that visible and ultraviolet light can damage the retina through production of superoxide radicals Antioxidants including beta-carotene vitamins A E and C and selenium protect against oxidative damage by acting as scavengers for the superoxide radicals
Epidemiologic data from the first National Health and Nutrition Examination Survey NHANES-1 are also consistent with a link between antioxidants and AMD the frequency of consumption of fruits and vegetables rich in vitamin A beta-carotene was negatively correlated with AMD after adjustment for demographic and medical factors
Data from this study will determine whether one 50-mg beta-carotene capsule taken on alternate days protects against the development of AMD and whether additional risk factors emerge after simultaneous controlling for other potential confounding factors
Reported diagnoses of AMD are confirmed by medical record review The primary analysis will be a comparison of incidence of reported AMD in the beta-carotene and placebo groups The Cox proportional hazards model will also be used to determine whether there is a difference in time to diagnosis of AMD between the two groups
The pathogenesis of AMD is only partly understood and its etiology remains obscure The Retinal and Choroidal Diseases Panel of the National Advisory Eye Council has stated that none of the fundamental causes of any type of macular disease is known and none can be prevented Thus this panel recommended that one of the NEIs program development priorities should be to initiate epidemiologic studies of macular diseases to identify possible causative protective or aggravating factors
This trial is part of the Physicians Health Study sponsored by the National Heart Lung and Blood Institute NHLBI of the National Institutes of Health with funding for eye epidemiologic data evaluations provided by the NEI It is an ongoing randomized placebo-controlled trial of aspirin in the prevention of cardiovascular mortality and of beta-carotene in the prevention of cancer Following randomization each of the 22071 physicians enrolled was assigned to one of four groups to take either aspirin or its placebo and beta-carotene or its placebo Followup questionnaires are sent 6 and 12 months after randomization and every 12 months thereafter The average length of followup is now greater than 12 years
The hypothesis that beta-carotene levels are inversely related to AMD is supported by experimental studies on the relationship between antioxidants and retinal morphology and function There is increasing evidence that visible and ultraviolet light can damage the retina through production of superoxide radicals Antioxidants including beta-carotene vitamins A E and C and selenium protect against oxidative damage by acting as scavengers for the superoxide radicals
Epidemiologic data from the first National Health and Nutrition Examination Survey NHANES-1 are also consistent with a link between antioxidants and AMD the frequency of consumption of fruits and vegetables rich in vitamin A beta-carotene was negatively correlated with AMD after adjustment for demographic and medical factors
Data from this study will determine whether one 50-mg beta-carotene capsule taken on alternate days protects against the development of AMD and whether additional risk factors emerge after simultaneous controlling for other potential confounding factors
Reported diagnoses of AMD are confirmed by medical record review The primary analysis will be a comparison of incidence of reported AMD in the beta-carotene and placebo groups The Cox proportional hazards model will also be used to determine whether there is a difference in time to diagnosis of AMD between the two groups
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None