Substance abuse and the eye

Smoking, binge drinking and drug abuse can lead to serious eye-health conditions, including glaucoma, even blindness.

By Karen Auge, Contributing Editor

What the 30-year-old male patient told Amanda S. Legge, OD, and what she saw, didn’t add up.

Two weeks earlier, he told Dr. Legge that he had dramatically and suddenly begun losing vision, and seemingly for no reason. No floaters, no pain, and no, he’d never had an eye exam before. And, he insisted, no illegal drug use. She suspected otherwise.

The patient’s primary care physician performed numerous tests, none of which uncovered anything that could explain his suddenly deteriorating sight.

But Dr. Legge’s evaluation turned up obstructed blood flow, Roth’s spots edema and nerve-fiber-layer hemorrhages, which pointed to septic chorioretinitis.

Figure. Without treatment, nearly half of those developing diabetic macular edema (pictured) will lose more than two lines of visual acuity. The link between heavy drinking and type 2 diabetes is well established.

Dr. Legge, of Wyomissing Optometric Center near Reading, Pa., questioned the man further. “He finally admitted he was injecting crack cocaine with vinegar, 10 to 15 times a week,” she says. She immediately referred him to a hospital, where further tests confirmed a devastating and likely drug-resistant infection.

Many providers may never encounter a patient who engages in that man’s kind of intensive illegal drug use. But it’s a safe bet that a few patients who walk into an ophthalmologist’s office on any given day may commit the health-care sins of smoking, heavy drinking and, in some cases, drug abuse. And they may not want to confess those transgressions.

While the commonly known consequences of those bad habits include cancer, diabetes and heart disease, smoking and drinking to excess and (even occasional) drug abuse will harm the eyes (see chart, page 35).

“A not-healthy lifestyle translates to a number of health problems,” says Robert J. Derick, MD, of Columbus Ophthalmology Associates in Ohio. “And a number of those are eye-related.”

VICES: DRUG USE

The extreme end

Illegal drug abuse is at the extreme end of these vices. An estimated 24.6 million Americans over age 12, or 9.4% of that age group, reported using illegal drugs in 2013.

The eyes do not escape deleterious impact.¹

Methamphetamine use, for example, is associated with retinopathy, corneal ulceration and retinal vasculitis.²

Intranasal cocaine use is particularly damaging, potentially leading to angle-closure glaucoma, retinal hemorrhages and optic neuropathy.³

“Clinicians need to be aware of the ocular problems that may be related to drug use so that pertinent questions may be asked regarding the cause,” wrote A.Y. Firth, MD, in a 2005 Eye editorial.³

VICES: SMOKING

Smoking

Many people still smoke cigarettes, despite decades of health warnings, public awareness-campaigns and increasing societal disapproval. The Centers for Disease Control and Prevention estimated that some 42.1 million (or 17.8%) of U.S. adults smoked cigarettes as of 2013.⁴

The U.S. Surgeon General has linked smoking to macular degeneration, cataracts and blindness.⁵ Smoking narrows blood vessels, which causes the normal blind spot to enlarge, and diminishes brightness contrast.⁶

In addition, partial or complete blindness due to retinal artery thrombosis is at least twice as frequent in smokers as in nonsmokers. Smokers of 20 or more cigarettes a day were two to three times more likely to develop age-related macular degeneration as compared with those who had never smoked.⁶

VICES: DRINKING

Alcohol

Heavy drinking may be an even bigger problem. One in six U.S. adults binge-drinks about four times a month, consuming about eight drinks per binge.⁷ So, some of your patients more than likely suffer the myriad health effects of excessive drinking.

The link between heavy drinking and type 2 diabetes is well established, as are the ocular consequences of diabetes. In addition, several studies have established excessive alcohol consumption as one potential factor in optic neuropathy, and a Boston University study found that consuming more than two “standard drinks” a day was associated with a significantly increased likelihood of cataract surgery.⁸

An Australian study from 2012 found that drinking more than 20 grams of alcohol a day — only about 0.68 ounces — was associated with an approximate 20% increase in the odds of early-onset of age-related macular degeneration.⁹

That’s not to say physicians ought to become modern-day temperance crusaders. A 20-year study of nearly 5,000 adults, known as the Beaver Dam Eye Study, found that people who drank no alcohol were more likely to experience vision impairment than people who drank a little.¹⁰ And, those who avoided alcohol use had a greater incidence of cataract surgery than those who were moderate drinkers.⁸

Screening for vices

Most physicians, including ophthalmologists, take a medical history of new patients; many do so at every visit. And it is routine for those intake surveys to include questions about smoking and alcohol and substance abuse.

Rather than asking, “Do you drink alcohol?” the more pertinent question is, “How much alcohol do you consume in a day or a week?” Most patients answer fairly honestly, says Andrew Iwach, MD, executive director of the Glaucoma Center of San Francisco and cofounder of the Eye Surgery Center of San Francisco.

Indeed, when another patient came to Dr. Legge with sudden and severe blurred vision, evidence pointed to infection. The patient readily admitted to regular heroin use, which paved the way for successful treatment of the infection with intravenous antimicrobial therapies, says Dr. Legge, who works not far from an area that is known for illicit drug activity.

Still, many patients conceal their bad habits. When they aren’t forthcoming, savvy physicians can often sniff out the deception — literally. “Ophthalmologists are often in close proximity to their patients,” Dr. Iwach said. “You kind of know what’s going on.”

Some telltale signs can help ophthalmologists to figure out which patients drink heavily, Dr. Iwach says. “For those with glaucoma, if you’re seeing them in the late afternoon, and the eye pressure looks really good — too good,” that may mean excessive drinking is happening. “Alcohol lowers eye pressure.”

Delicate discussions

Faced with such evidence, ophthalmologists must build trust with patients if they want to wade into the minefield of their personal vices. “A key part of medicine is you have to deal with each patient as an individual,” Dr. Derick says. “And each will respond as an individual. As ophthalmologists, we have an advantage: We can develop relationships with patients over months and years and get to know patients and how to approach the subject.”

If the patient smokes or drinks, Dr. Iwach recommends broaching the subject with concern and a sincere desire to help, rather than with judgment or lectures. “Make them comfortable enough to tell you the truth. Let them know you understand these are not easy habits to break.”

It’s hard to conceive that U.S. adults are unaware of the risks of heavy drinking or smoking. Still, hearing that some of those harmful effects may really apply to them — and may compromise their sight — can jolt patients into action, Dr. Iwach says. “When they hear they are at risk of vision loss, that’s powerful motivation.”

It can be a tricky discussion. But, as Dr. Legge has discovered, the fruits of such honest conversations can provide practitioners with the tools to potentially save a patient’s eyesight. OM

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