Metacognition and its impact on physician self-diagnosis

We recently spoke with Nayan Kothari, MD, associate dean for education, chair and program director of the department of medicine at Drexel University College of Medicine/Saint Peter's University Hospital in New Brunswick, N.J. He is 74 years old with long-standing spinal stenosis. He told us that his condition did not prevent him from biking and hiking regularly, and he was otherwise in good health. His medications included baby aspirin, atorvastatin (Lipitor) for elevated cholesterol, and losartan (Cozaar) for mild hypertension.

In late spring of this year, he and several friends visited Disney World in Orlando, Fla., where he went on the “Mission: SPACE” ride at Epcot. This ride has a multiple-arm centrifuge that spins and tilts to simulate the illusion of speed and gravitational force of up to 2.4 G, more than twice the force of the earth's gravitational pull.

“You spin like you are in a washing machine,” said Dr. Kothari.

He knew immediately that going on the ride was “a mistake.” As a child, he was very prone to motion sickness and never went on carnival rides. But once strapped into his seat, he could not get off. He told us that the ride lasted for five and a half minutes, and when he exited, “I had an intense headache, different from anything I'd ever had before, and intense vertigo.” He could not stand, so he lay down on the grass for 20 minutes, and then felt better.

That night, he had dinner with friends and felt fine, but awoke at 12:15 a.m. with the sensation that he was suffocating. He opened the hotel window and considered whether he might be having acute heart failure or a pulmonary embolus. But he found that jogging in place ended the symptoms, so he went back to bed.

At breakfast the next day, he suffered the same symptom of a feeling of suffocation. He moved outside to a parking lot, where he jogged aggressively, and then felt much better. “So, I realized that it was not cardiac or pulmonary,” he said, “and more likely a panic attack.”

Later in the day, he went on a treadmill in the hotel gym, setting the pace at 6 miles per hour at a 6% incline, and exercised for 45 minutes. “I basically gave myself a stress test,” he said, adding, “I knew it was ridiculous when I did it.”

He was afraid to get on a plane to return home, fearing another panic attack. He contacted his physician, who prescribed paroxetine (Paxil) for the trip home. After returning, he suffered from similar attacks every night. A psychiatrist told him that he could well have post-traumatic stress disorder and prescribed clonazepam (Klonopin) for sleep.

Over the ensuing weeks, he felt good, and in early June he traveled with his family to the Midwest for a wedding. While in the airport, his son said, “Dad, you are getting old.” He told us, “I gave him a speech on aging.” But after the wedding, his daughter also commented, “Dad, you are walking like an old man.”

He told us that he had not appreciated his change in gait, but when his children pointed it out to him, he attributed it to his long-standing spinal stenosis. His children insisted that he consult with a neurologist.

On examination, he had ataxia and the neurologist suspected a cerebellar stroke. An MRI was obtained and showed the unexpected finding of bilateral subdural hematomas, 21 centimeters in diameter on the right and 19 centimeters in diameter on the left.

“When I looked at the images, I wanted to faint,” he told us. “I had never considered a brain injury.”

He contacted a neurosurgeon at his hospital and explained that he was asymptomatic, had patients to see, would be taking morning report, and had other work to do, so he preferred to defer the surgery for two days.

The day following the MRI, he felt fine and drove himself to the office. He wrote down a series of notes for his secretary to type but found that she was unable to read his writing.

“She has worked with me for 15 years, so I realized that my handwriting had changed dramatically,” he said.

He decided to walk to his neurosurgeon's office but collapsed in the hospital corridor.

“I was severely ataxic, like a drunk, banging into the walls,” he said.

He was taken by wheelchair to the neurosurgeon's office and was sent directly to the operating room. Burr holes were made in his skull.

“The neurosurgeon later told me the blood came spurting out three feet into the air, it was under such pressure. I think that I was on the verge of herniating,” he said. He also learned that the blood had the dark color of a prior hemorrhage, several weeks old, likely dating to the time of the Disney space ride.

The next morning, he was able to walk without any ataxia, and he was discharged the following day. “My balance is still not completely normal, so I'm getting physical therapy,” he said. “And the panic attacks have persisted.”

Dr. Kothari was born in India and trained in internal medicine and rheumatology there as well as in the United States and in the United Kingdom. He was raised largely by his grandmother, who lived to be 100. She was fond of saying, “Stay away from lawyers, doctors and prostitutes, because each can get you into trouble.” He added with a laugh, “Of course, her husband was a lawyer and her son was a doctor.”

When it comes to his personal health, Dr. Kothari prefers to avoid doctors and medical interventions and believes “less is more.” We term this a “minimalist” mindset. In contrast is the “maximalist” mindset: aggressively proactive, everything to the maximum.

In our field research interviewing patients and physicians, we have noted how family history, particularly the longevity of close relatives, is a powerful influence in shaping the minimalist mindset. However, here, medical treatment could not be avoided. Yet Dr. Kothari decided to delay his surgery by a few days to complete his work in his office.

All of us as physicians are prone to both self-diagnosis and self-management. In this case, the physician, a rheumatologist, fixed on the diagnosis of his long-standing spinal stenosis as the cause for his observed change in gait. Such an error in thinking is termed “anchoring,” where we seize or anchor onto a first hypothesis to explain clinical findings and stay stuck there, failing to consider other possibilities.

“Although I teach the anchoring error to the residents,” Dr. Kothari told us, “I could not avoid it myself.”

Even expert knowledge about cognitive biases does not protect us from their power to skew our thinking. Daniel Kahneman, PhD, the Nobel laureate who first named the anchoring error with the late Amos Tversky, recently noted that he himself is prone to cognitive errors despite a lifetime of study of the heuristics or thinking shortcuts. Metacognition refers to thinking about one's own thinking, a skill that psychologists like Dr. Kahneman aim to acquire, and that physicians should also practice.

Dr. Kahneman said in his book “Thinking, Fast and Slow” that “Except for some effects that I attribute mostly to age, my intuitive thinking is just as prone to overconfidence, extreme predictions and the planning fallacy as it was before I made a study of these issues. I have improved only in my ability to recognize situations in which errors are likely.”

As doctors, we need to realize that such situations include decisions about our own health.