Medical Mystery: Out of Nowhere, Amnesia

On the way, Margot anxiously asked me again, “Did I throw up?”

After I woke Drew, he did a quick assessment intended to identify a stroke. He gave Margot three words to remember: apple, cat, tree. He tested her muscle control by asking her, among other things, to raise her eyebrows, press her palms against his hands, and wiggle her toes.

She could do all that equally well on the left and right sides of her body. That was good.

But when Drew asked Margot to tell him the three words he’d given her, she was stumped. She couldn’t even remember that he’d given her any words.

Desperate for answers

The doctor on duty at the resort called for an ambulance. She thought Margot might have had a transient ischemic attack (TIA) — a mini-stroke — or some other “cardiac event.”

By 6:30 a.m., Margot, Drew and I were in the emergency room of a hospital in Punta Cana. Margot’s vital signs were normal. We gave the ER doctor some background: Margot, age 61, took cholesterol medication. She’d had a lingering cough. She’d thrown up that morning. (Several other relatives had gotten sick, too, we learned later — likely from food poisoning or norovirus.) Could the coughing and vomiting have dislodged arterial plaque, leading to a stroke?

As we waited for the results of blood tests and a CT scan, bits of Margot’s memory returned. When Drew gave her three new words, she could recall two of them. She suddenly remembered wanting to tip two women at the resort’s spa. True to her old self, she remembered their names.

The doctor returned. The blood test indicated a bacterial infection, which probably explained the vomiting. The CT scan showed no signs of a stroke.

After spending the night in the hospital — Happy New Year! — Margot was discharged and we were on our way home. She was still hazy about recent events, unsure whether she was recalling dreams or actual memories. Otherwise, her memory and ability to form new memories seemed fine.

So if this wasn’t a stroke, what was it? Drew had a suspicion. And back in the U.S., a medical journal article and three different doctor visits confirmed it.

A 24-hour scare

Margot didn’t have a TIA. She had TGA, or transient global amnesia — a “pretty classic” case, her primary care doctor commented. It’s a rare condition that, when it does strike, mostly affects people 50 and older, according to a 2022 article in the journal American Family Physician; actor Liev Schreiber, 57, and Survivor host Jeff Probst, 63, have both spoken about recent episodes of TGA as well. Its key symptoms are an inability to form new memories, some loss of previous memories, and confusion for up to 24 hours. The physiology behind TGA is unclear, and there’s no established treatment. If you have it, you just have to wait it out.

The trigger of TGA is often a physically or psychologically stressful precipitating event, according to researchers. This might include emotional stress, significant physical exertion, exposure to extreme temperatures, high-altitude conditions, acute illness or sexual intercourse. Margot checked three of those boxes: emotional stress (a relative’s medical crisis), acute illness (vomiting) and extreme temperatures (back-to-back visits to the spa’s cold plunge pool and steam room).

It was no wonder that identifying her TGA took some time. That’s because the age group most susceptible to it is the same age group most at risk for a stroke, says David Sealy, M.D., a professor at the Medical University of South Carolina and founder of the Sports Medicine Fellowship in Greenwood, South Carolina. Another problem is that the condition isn’t common knowledge, even among health care professionals. “In the medical world, I’d guess that 80 percent or more are not familiar with the diagnosis,” says Sealy, who co-authored the American Family Physician article.

Sealy has had a glimpse of that unfamiliarity himself. More than a decade ago, he had his own onset of TGA while on a ski trip in Colorado. (Physical exertion, extreme temperatures and high altitude: Check, check and check.) “It was a mountain I’d been skiing on a hundred times, and I didn’t know where I was,” he says. But when he was brought to the hospital, he says, “the neurology fellow there missed the diagnosis.”

Awareness of TGA, however, doesn’t mean you can identify it on your own. “It is good to seek emergency care if it’s an older person with amnesia,” Sealy advises. In general, the appropriate course of action is to get a brain MRI, he says. If that shows no signs of a stroke and the person with amnesia shows no motor or sensory deficits, he says, “you’re safe.” (The CT scan that Margot got likely wouldn’t have caught a smaller stroke.)

Happily for Margot and most other people hit by TGA, the chances of a repeat episode are minimal. (The risk is higher, however, for people with a history of migraines or an episode of TGA before turning 50.) Sealy, in fact, has been out on the ski slopes more than 50 times since his TGA with no worries about a recurrence. “I like my odds!” he says.