The study, appearing in the September issue of the British Journal of Ophthalmology, found those who had macular degeneration were less likely to have filled a prescription for statins.
Other experts urged caution, however, because no evidence was found that the drugs were the reason the users were less likely to have eye trouble.
"This should not be put forward as a reason to go out and take these drugs," says Dr. Michael Marmor, an ophthalmology professor at Stanford University School of Medicine in California. "The authors did not show a direct cause-and-effect relationship, only an association. There are a number of theoretical explanations."
Among those: People taking statins may also have had better lipid levels or may have been taking care of themselves better.
According to the study authors, macular degeneration, also known as age-related maculopathy (ARM), is the leading cause of irreversible vision loss among older adults in the United States.
It is caused by the deterioration of light-sensitive cells in the part of the eye known as the macula. Older people as well as people who smoke appear to be more vulnerable to the condition, and there are few effective treatments.
In certain groups of people, however, antioxidants can slow the progression of the disease, says Dr. Craig Greven, vice chairman of the ophthalmology department at Wake Forest University School of Medicine.
Because there is speculation that cardiovascular disease and ARM share some risk factors, there has been additional speculation that some of the same biological processes may be at work.
The authors of this study looked at 550 people who had been recently diagnosed with ARM and compared them to 5,500 people who ostensibly did not have ARM. All the participants were at least 50 years old.
People with ARM turned out to be 50 percent less likely to have received and filled a prescription for statins relative to the control group. This was true regardless of whether the person was currently taking statins or had taken them in the past.
There was a stronger association between statins and ARM among people who also had diabetes, lipid metabolism disorders, hypertension and arterial disease.
Also, participants with ARM were more likely to also have diabetes, high blood pressure or vascular disease, but there were no differences between them and the comparison group in terms of arterial disease or lipid metabolism disorders.
There may be some methodological problems with the study. "Two-thirds of the people who were included in this study never had an eye exam to confirm whether they had macular degeneration or not and a lot of people in the control group may have had macular degeneration," says Greven. "I think that is a big problem."
But the authors, and others, point out the findings are extremely preliminary. "It’s an interesting observation, but certainly a lot more work and research into this needs to be done before any suggestion about statin use and macular degeneration can be made," Greven says. "We can’t really change our clinical practice based on this information." |
