The times, they are a-changin' (and bringing new syndromes)

When are symptoms due to a medical condition, and when are they just a part of life? That's the question that came to mind as I read about "computer vision syndrome."

So, what is a syndrome, anyway?

Before considering the health hazards of working long hours in front of a computer screen, it's worth asking what a syndrome is. In medicine we often use the word syndrome to describe a group of features, such as symptoms, examination findings or test results, that tend to occur together but without a clear enough understanding of their cause to be considered a specific disease.

Some syndromes are described by the part of the body involved: carpal tunnel syndrome, for example, is caused by the compression of a nerve in a narrow part of the wrist called the carpal tunnel. Other syndromes are named for the person or persons who were among the first to describe them: Down syndrome is a genetic disorder named for the British physician Dr. John Langdon Down, who described it in 1862 — well before its cause (an extra copy of chromosome 21) was recognized. Still others are named for the problems they cause. For example, restless legs syndrome" tells you a lot about the symptoms that people with this condition experience. But in many cases, the difference between calling a condition a "syndrome" and simply describing a cluster of symptoms is more about language than about science or medicine.

Eye strain? Or computer vision syndrome?

My medical dictionary lists more than 600 conditions as "syndromes." Well, now we can add one more: a recently published report describes a new syndrome: "computer vision syndrome." This is a condition increasingly recognized among people working long hours on a computer who complain of eye problems including:

• dryness
• blurry vision
• double vision
• a burning sensation in the eyes.

Symptoms may be severe enough to interfere with continued computer work.

Is computer vision syndrome a major public health problem?

The authors of the report suggest that up to 70 million people worldwide are at risk for computer vision syndrome. And this number is likely to grow, considering the large (and increasing) numbers of students and employees who rely on their computers for many hours each day. According to the researchers, up to 90% of people who use a computer for prolonged periods of time will report one or more of these symptoms. And that's not counting other health problems linked to extensive computer use, including back, neck, and shoulder pain; carpal tunnel syndrome; and headaches. Together, it's enough to make you view an ordinary computer as a potential health hazard.

Why are vision problems so common with computer use?

The authors of this paper suggest several explanations for computer vision syndrome:

• The text and images on a computer screen are made up of pixels with blurry edges. The eyes have to work harder to focus on them compared with text and images on a printed page. This may lead to eye strain.
• Reduced blinking is another potential issue. People tend to blink less frequently than usual when working on a computer. (Normally, we blink about 17 times a minute, but this often drops to 12-15 times a minute during computer use.) Less blinking can lead to dryness.

What's to be done?

There are a number of ways to combat computer vision syndrome:

• Don't sit so close. Ideally, the computer screen should be about two feet away from your face.
• Position the monitor well. Experts recommend that the center of the monitor should be 4 to 8 inches lower than eye level. Looking down a bit while working means the eyes are less exposed and therefore less likely to become dry.
• Optimize contrast. Black text on a bright white screen is best.
• Minimize glare. Dimming overhead lights, lowering window shades, using an anti-glare flat-screen monitor, and wearing special glasses can all be helpful.
• Take breaks. Try the 20-20-20 rule, for example: take a 20-second break every 20 minutes and focus your eyes on something at least 20 feet away. While you're at it, stretch your neck and shoulders.
• Combat dryness. Blink often and use moisturizing eye drops if necessary. Avoiding air drafts and using moisturizing compresses can also help.
• Change the font size. Use a larger font or magnify the viewing display if that makes it easier to see.
• Get your eyes checked at least yearly. Many people strain their eyes while using their computers because their prescription for glasses or contacts is outdated. Let your eye doctor know of any problems you're having. Bifocals or progressive lenses can make a big difference, especially if you do a lot of moving back and forth between the computer screen and printed material.

What's next?

Computer vision syndrome may be the newest technology-related threat to public health, but new syndromes related to changes in how we work and play is nothing new. I recall a form of tendinitis called "Blackberry thumb" being described as a "scourge" in 2005, when texting on the new wireless device was becoming common. It's a reminder that as our technology changes, some impact on our health is probably inevitable.

And whether we consider it a new disease, a new syndrome, or just a part of working long hours in front of a computer screen, the most important thing is to recognize the problems described by computer vision syndrome and take measures to prevent and treat them. That's particularly true because computer vision syndrome may be the latest technology-related syndrome to be described, but it probably won't be the last.