Long-term multivitamin use decreased the risk of cataract in middle-aged men but had an insignificant impact on age-related macular degeneration, according to a large study.
“Given that an estimated 10 million adults in the United States have impaired vision due to cataract, even a modest reduction in risk of cataract has potential to improve public health outcomes,” the study authors said.
The Physicians’ Health Study II (PHS II), a randomized, double-blind placebo-controlled trial, included 14,641 male American physicians aged 50 or older; 7,317 physicians received an active multivitamin, vitamin C, vitamin E and beta carotene and 7,324 received a placebo multivitamin.
The primary outcome measures were incidence of cataract and visually significant age-related macular degeneration (AMD) that diminished best corrected visual acuity to 20/30 or worse. Mean follow-up was 11.2 years.
Overall results showed 1,817 cases of cataract and 281 cases of visually significant AMD.
Cataracts were identified in 872 patients in the multivitamin group and 945 patients in the placebo group. The risk of cataract was 9% lower in the multivitamin group than in the placebo group. The between-group difference was statistically significant (P = .04).
The risk of nuclear cataract was 13% lower in the multivitamin group than in the placebo group (P = .005).
AMD was identified in 152 patients in the multivitamin group and 129 patients in the placebo group. The between-group difference was statistically insignificant. Further study of AMD findings is warranted, the authors said.
Disclosure: See the study for a full list of all authors’ relevant financial disclosures.