A study in Environmental Health Perspectives suggests long-term lead exposure may be a risk factor for primary open-angle glaucoma (POAG), the most common type of this disease.
POAG develops when the inner-eye fluid, called aqueous humor, does not drain properly. Gradually, eye pressure builds to dangerous levels and can cause optic nerve damage and permanent vision loss. This eye condition is complicated because it is incurable, and vision loss is permanent and irreversible.
For years, researchers have linked glaucoma to a combination of risk factors including age, heredity, medication and health history. This study is unique because it suggests your environment could affect glaucoma risk.
Bone Lead Levels Affect Glaucoma Risk
Oxidative stress can elevate eye pressure and damage the optic nerve. Sung Kyun Park, an environmental health scientist at the University of Michigan, led a study on lead exposure and oxidative stress. Park wanted to learn whether chronic lead exposure affected glaucoma risk.
Because blood tests only measure recent exposure to lead, they were inadequate to analyze long-term contact with lead. Park decided to measure lead levels in the knee and leg bones because bones store lead for decades.
Park analyzed patella and tibia lead levels from a subset of participants in the VA Normative Aging Study, a study that has followed 2,280 men since 1963. The research team tracked ophthalmologic and bone lead level data on 634 men and identified 44 new cases of primary open-angle glaucoma (POAG).
Park estimates POAG risk was about “five times higher with a 10-fold increase in patella lead and about three times higher with a 10-fold increase in tibia lead” (EHP).
Although this research found strong evidence linking long-term lead exposure and POAG, Park needs to conduct further studies. He wants to examine the effects of other metals on POAG, as well as exposure at an early age.
Know Your Glaucoma Risk
According to the Glaucoma Research Foundation, more than three million Americans have glaucoma, but only half are aware they have the disease. It is imperative that you know your own risk for glaucoma. You are at higher risk for glaucoma if you are:
- 45 years of age or older
- African American
- Taking steroids (orally, injected or eye drops)
You can learn more by taking our Glaucoma Risk Assessment. In only a minute, you can find out whether you are at elevated risk for vision loss.
Finally, you can take active steps to preserve your eye health by exercising regularly and eating a diet high in fruits, vegetables, whole grains and lean proteins. Annual comprehensive eye exams with your ophthalmologist are essential to evaluate your eye health and overall wellness. If it has been over a year since your last appointment, call your ophthalmologist to schedule a check-up.