The controversy over Biden and Parkinson’s disease, explained

The murmurs about President Joe Biden’s health — and particularly commentary about whether he’s exhibiting signs of Parkinson’s disease — have reached a fever pitch.
On Monday, the New York Times reported that a Parkinson’s specialist visited the White House eight times between July 2023 and March 2024, raising questions about whether the president was quietly being evaluated and treated for the condition.
That was followed by a contentious White House press briefing in which press secretary Karine Jean-Pierre was bombarded by questions about the president and Parkinson’s. “Has the president been treated for Parkinson’s? No. Is he being treated for Parkinson’s? No, he’s not. Is he taking medication for Parkinson’s? No,” Jean-Pierre parried.
Later that evening, the White House released a letter from Kevin O’Connor, the president’s physician, which noted that the president “has not seen a neurologist outside of his annual physical.” The letter also implied that the Parkinson’s specialist mentioned in the New York Times story, Kevin Cannard, had been to the White House over the years to see other staffers and military members in his capacity as neurologist to the White House medical unit, which he’s held since 2012.
O’Connor referred back to the results of a medical exam released in February that reported “no findings which would be consistent with … Parkinson’s,” among other conditions. The neurological exams as part of the annual physicals were conducted by Cannard, according to O’Connor’s letter.
But that letter has not tamped down the speculation. On Wednesday morning, NBC aired an interview with a neurologist, who declared, “He has Parkinsonism. That is a fact. He has degeneration of the brain.” (More on “Parkinsonism” below.)
To be clear, it’s hard to make a Parkinson’s diagnosis from afar, says Anthony Lang, a neurologist and researcher who leads Parkinson’s disease research at the University of Toronto’s Tanz Centre for Research in Neurodegenerative Diseases. “I’d be very reluctant to come to any specific conclusion without a clear, hands-on assessment of the individual,” he says.
But the reason doctors like CNN medical correspondent and neurologist Sanjay Gupta, among others, have been vocal is that the movement changes typical of Parkinson’s — even if they’re caused by a different condition — can be fairly straightforward to the trained eye. And according to Lang and doctors I’ve spoken with, and in my own view as a doctor, further neurological testing would be the most reasonable recommendation based on what we’ve observed.
That’s why speculation about the disease has picked up — and why the controversy might linger.
It’s a well-known fact that Joe Biden is 81 and moves his age. What kickstarted the latest bout of speculation about deeper health problems was his disastrous June 27 debate performance against Donald Trump.
During the debate, Biden often spoke haltingly, occasionally losing his way mid-thought, and while his opponent spoke, his face was often frozen and expressionless. A tsunami of commentary about his health followed, including speculation about Parkinson’s.
In a column published on CNN’s website July 5, Gupta wrote that he and “more than a dozen” of his neurologist colleagues had been stunned by the president’s “confused rambling; sudden loss of concentration in the middle of a sentence; halting speech and absence of facial animation, resulting at times in a flat, open-mouthed expression.”
What Gupta and some medical experts seized upon were some classic symptoms. Parkinson’s involves changes in the way people move, and often, later in the disease, cognitive problems like dementia. In this illness, many of these symptoms are caused by a problem with the brain’s production of dopamine, a molecule involved in signaling body parts to move.
The changes in movement caused by the condition are so characteristic that doctors often group them together using the condition’s name, whether or not the diagnosis has been made. Parkinsonism is an umbrella term that describes a combination of slowness, stiffness, a flexed posture, decreased facial expressiveness, soft speech, gait changes (including a slower, shorter stride), and often, tremors.
Although primary care doctors are commonly the first to identify these findings based on a patient’s physical exam, specialists are often involved in confirming a Parkinson’s diagnosis and managing treatment. A full neurologic exam aimed at making the diagnosis includes observing a patient in action and putting them through a range of active and passive movement exercises.
Other tests, including brain MRIs and spinal taps, can help rule other conditions out, or are used in research settings to help make a diagnosis in select patients — but “it really is mainly clinical diagnosis,” says Lang. In other words, it’s a diagnosis made by observing and examining a patient, not by doing lab tests or CT scans.
People can have Parkinsonism without having Parkinson’s disease. Drugs that block or deplete dopamine — for example, antipsychotic drugs and medicines used to treat some gastrointestinal conditions — can cause these symptoms. Less commonly, so can brain tumors and strokes. That’s part of why doctors are hesitant to speculate on Biden’s diagnosis (or anyone else’s) purely on the basis of observing his movements and speech on video.
Although Parkinson’s motor symptoms can be minimized with medication, it’s a progressive and debilitating illness with cognitive components that loom larger with age. Stress temporarily worsens the disease’s symptoms, and maintaining stamina can be especially challenging for people with the condition: About half of all people with Parkinson’s say fatigue is a major problem. Dementia is incredibly common in older people with the disease, affecting around 80 percent, and can come on relatively quickly.
Oral medications and other treatments exist that help reduce the condition’s physical symptoms, although there’s no known way to slow its associated cognitive changes. Synthetic forms of dopamine are a cornerstone of Parkinson’s treatment, and other medicines (including some that mimic dopamine’s effects) may also be helpful. Some people in late stages of the disease may benefit from a surgically implanted device called a deep brain stimulator, which sends electrical impulses from a tiny pacemaker-like box implanted in the chest to electrodes implanted in the brain.
Doctors inexperienced in evaluating Parkinson’s may miss the diagnosis, attributing its symptoms to normal aging. However, the condition involves findings that skilled clinicians can typically identify using certain maneuvers. A physical exam also involves close observation of the patient for the posture and gait changes, masked face, tremor, and other typical signs. Not all patients have all the symptoms, and especially early in the disease, some symptoms may be absent, which may complicate or delay diagnosis and treatment.
For Joe Biden, the president of the United States, the stakes of getting that assessment are higher than the average person’s.
For his part, Lang echoes what Gupta and other expert sources have floated: The president should undergo cognitive testing and other evaluations to determine the causes of his physical changes. “If the results indicate an issue, then they should deal with it honestly and appropriately,” Lang says.
There is simply not enough evidence from observing Joe Biden on TV to say that he definitely has Parkinson’s. But the reason why some medical experts have felt comfortable piping up is there is enough evidence to recommend further testing — even with the results from the February medical exam. Barring a sudden change in how the president moves, talks, and acts, the speculation isn’t likely to go away anytime soon.