People with age-related eye problems, such as age-related macular degeneration and cataracts may not live as long as those without them, says a new study. A cataract involves the lens of the eye becoming cloudy and can cause partial blindness.
In a study of 4,753 people aged 55 to 81, people with macular degeneration, a progressive condition that causes gradual vision loss, had a 41-percent higher risk of death during the 6.5-year follow up than people without signs associated with the disorder.Researchers also found people who had cataract surgery had a 55-percent higher risk of death than those with good vision, while those with vision worse than 20/40 in one eye had a 36-percent higher risk.
However, a subgroup of participants was randomly assigned to take zinc, and these patients had a 27-percent lower mortality rate than those not taking zinc. "The beneficial effects of zinc on mortality in this study may be related to an improved immune response, which is known to decrease with aging," say researchers.
While the exact mechanisms are unclear, the study showed the decreased survival rates for people with either cataracts or macular degeneration, suggests that these conditions may reflect systemic rather than only local processes. Thus researchers conclude saying that the improved survival in individuals randomly assigned to receive zinc requires further study.