Study Links SSRI, SNRI Use to Increased Cataract Risk

In a large population of patients studied in Quebec, the current use of selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs) was associated with a significant increase in the risk of developing cataracts. The study looked at over 200,000 patients, 18,784 of whom had cataracts and 187,840 of whom had no cataracts.

About 5.7% of patients with cataracts were taking SSRIs or SNRIs, while only 4.4% of the group without cataracts was taking these medications. Researchers calculated that this demonstrated a roughly 15% increased risk for cataracts among current SSRI or SNRI users. Previous use of the medicines were not associated with any increased risk. The risk was not equal for all medications. Fluvoxamine  (Luvox) (39% increased risk) and venlafaxine (Effexor) (33% increased risk) were associated with the highest increased risk, while fluoxetine (Prozac), paroxetene (Paxil), citalopram (Celexa), and setraline (Zoloft)  did not have statistically significant increased risk. Researcher caution that the variation in risk and the lack of risk for some SSRIs and SNRIs does not mean the drugs are safer,  but is more likely due to a lack of statistical power to determine the risk of individual drugs.

The study was limited because it utilized an administrative database and was therefore unable to check for other risk factors, which for cataracts includes smoking, ultraviolet exposure, and use of steroids. It was also unable to distinguish the severity of cataracts, but only whether a person had cataract surgery following diagnosis.

And if you are beginning to suffer vision loss due to a darkening of your crystalline lens, talk to a local cataract doctor to learn about your surgical options.

Aspirin to Prevent Cataracts?

Cataracts are a progressive blockage of light in the eye’s lens, which sits behind the iris. Vision depends on clarity in both the lens and the cornea (clear front part) so that light can enter the eye and focus on the retina (the back inside surface). Both the cornea and lens bend (refract) the incoming light so that in a 20/20 eye it focuses clearly regardless of what distance it is coming from. In other words, the person has clear vision at all distances.

How do Cataracts Form?

Cataracts are small opacities in the lens which gradually grow larger. The lens consists mostly of water and proteins. A cataract is a tiny clump of protein cells and typically they start to form after middle age.

The lens protein is becoming denatured – disrupted in its cell activity. When we boil an egg we are denaturing the egg protein and making it hard. If we leave milk sitting out until it curdles, that is denatured milk protein. Denatured cells tend to aggregate – that is, cross-link or clump. Cataracts are denatured lens protein.

Cataracts are not inevitable like presbyopia, but there are risk factors such as:

  • Extensive exposure to UV rays
  • Family history of cataracts
  • Radiation exposure
  • High blood pressure
  • Diabetes

Cataracts begin slowly, at first causing no vision impairment. As they expand and increase in number they involve more and more of the lens, and if nothing is done they will cause complete blindness.

What Does Aspirin Do?

Aspirin (acetylsalicylic acid) is a non-steroidal anti-inflammatory drug (NSAID). It is commonly taken to relieve pain, reduce fever and reduce inflammation. It also “thins the blood”, meaning that it reduces the blood’s tendency to clot. Therefore it is taken in daily low doses to help prevent heart attacks and strokes which might otherwise be caused by a blood clot.

The University of Reading in the U.K. has ongoing research at its School of Animal and Microbial Sciences (AMS). The head of AMS is Professor James Crabbe who presented his findings at a recent gathering of people interested in aging.

“We have found that aspirin inhibits the protein cross-linking process responsible for cataract”, he said, suggesting that aspirin “could delay the onset of cataract by 43 percent”. Similar studies of ibuprofen (Advil and Motrin) have suggested that these drugs could reduce cataracts by 50 percent.

At present there is no way to remove cataracts from the lens once they form. Instead the lens must be removed from the eye and replaced with an artificial lens. It would be a great step forward in eye care if ophthalmologists could prescribe preventive treatments for cataracts, such as a daily aspirin, Advil or Motrin.

Advances in Cataract Research May Help with Early Detection

You may not know that cataracts are the leading cause of vision loss worldwide. Recently, researchers from the National Eye Institute (NEI), which is part of the National Institutes of Health (NIH), along with NASA worked together to create a very simple and safe eye test for measuring a protein that is associated with cataract formation. If subtle protein changes can be detected before cataracts develop, people may be able to reduce their risk of developing cataracts by making slight behavioral changes. Decreasing exposure to the sun, quitting smoking, controlling their diabetes and avoiding certain medications are just some of the changes that can be made early to prevent the development of cataracts.

If a person’s eye appears cloudy from cataracts, it’s too late to reverse the process or even treat it medically. The new technology can detect the earliest damage to the len’s proteins, which is a red flag for the development of cataracts.

The NEI is our country’s lead agency for vision research that leads to sight-saving treatments. The NIH is the country’s leading agency for conducting and supporting medical research. The NIH investigates the causes, treatments and cures for common and rare diseases.

If you feel you may be developing cataracts, please contact an ophthalmologist in your area today to see about having your eyes tested for cataracts and other vision problems.