The cholesterol-lowering medications known as statins may improve circulation in the eye, potentially reducing the risk of certain eye diseases, according to a study in the May issue of Archives of Ophthalmology.
Statins have previously been shown to relax blood vessels and reduce the risk of stroke and heart disease, even in patients without high cholesterol, according to background information in the article. The effect of statins on circulation in the retina has not been studied previously, but researchers have found that long-term use of statins may reduce the risk of glaucoma, age-related macular degeneration and other eye conditions. These diseases are thought to be associated with problems in circulation in the eye.
Taiji Nagaoka, M.D., Ph.D., Asahikawa Medical College, Japan, and colleagues randomly assigned 12 healthy men (average age 21 years) to receive either a 20-milligram dose of simvastatin or an identical placebo each morning for seven days. The researchers measured blood flow in the men's retinal arteries and veins at the beginning of the study, 90 minutes after administering the drug the first day and at the end of seven days. They also assessed the participants' blood intraocular pressure, or the pressure within the eyeball. The seven-day regimen was repeated again 28 days after the first phase of the study ended.
Among patients taking statins, intraocular pressure was reduced 90 minutes after taking the medication and at the seven-day mark. Blood velocity (speed) and blood flow were significantly increased in patients who had taken statins for seven days, although the size of the blood vessels did not change.
These findings may have implications for several eye diseases, the authors write. For instance, diabetic retinopathy, which occurs when poorly controlled diabetes damages the eyes and which can eventually lead to blindness, was recently linked to reduced blood flow in the eye. "Although the findings in the present study are obtained from healthy men whose physiological response to simvastatin may be different from that of patients with diabetes, the increased retinal blood flow associated with treatment with simvastatin may be a potential therapy for diabetic retinopathy," the authors write.