Lead Exposure and Cataract Risk in Men.

Date:

10-Dec-2004

Source

JAMA

Related Monographs

Consumer Data: Ocular Health
Professional Data: Ocular Health

Article

The eyes are mounted in a prominent position on the head, and thus are vulnerable to a variety of disturbances. Our vision can be damaged by trauma, exposure, or infection and there are many diseases of the eye including glaucoma, cataracts, or retinal detachment. Other diseases may have ocular symptoms, as do some of the neurologic diseases affecting areas of the cortex, thalamus, and brainstem that are devoted to visual perception or to the execution of eye movements. Although it may be determined that a patient requires specialized eye care, the initial examination and assessment of visual acuity, pupils, eye movements, and visual fields, can be done by a general practitioner.

A cataract is a clouding of the lens sufficient to reduce vision. Most cataracts develop slowly as a result of the aging process, and lead to a gradual reduction in vision. The only treatment is surgical extraction of the opacified lens. Remarkable technical innovations have made it possible to remove the cataract while leaving the lens capsule intact. A plastic or silicone lens is then placed in the empty lens capsule, replacing the natural lens, and most generally leading to improved sight in most patients.

A recent study stated that low-level lead exposure could lead to chronic diseases. This study, published in the Journal of the American Medical Association, investigated the role of lead exposure and risk of cataracts. Using 795 men from an aging study conducted in Boston, MA, tibial and patellar bone lead levels were measured in these men. Blood lead levels were also measured. The men followed were over the age of 60 and had sufficient ocular information available. There were 122 cases of cataracts reported. After comparing to lead levels, they found that lead from the patellar tests were associated with a higher risk of cataracts. This association was not seen in the blood tests, due to the fact that blood levels indicate short-term lead exposure. The authors concluded that, “These epidemiological data suggest that accumulated lead exposure, such as that commonly experienced by adults in the United States, may be an important unrecognized risk factor for cataract. This research suggests that reduction of lead exposure could help decrease the global burden of cataract.”1

References

1. Schaumberg DA, et al. Accumulated Lead Exposure and Risk of Age-Related Cataract in Men. JAMA. 2004;292:2750-2754.