Opinion: It’s time to find out whether Biden has cognitive impairment or not

Editor’s Note: Jonathan Reiner, MD, is a CNN medical analyst and professor of medicine and surgery at George Washington University. The views expressed in this commentary are his own. View more opinion on CNN.

There’s a tenet of medicine that states, “You only find what you look for.”

Last week, in the wake of a poor debate performance, President Joe Biden was asked multiple times by George Stephanopoulos if he would agree to undergo a cognitive screening examination. The president demurred, saying that the duties of the presidency and “running the world” prove his mental fitness for the job: “Look, I have a cognitive test every single day.”

This is no longer sufficient.

In June, 51 million people tuned in to watch the much-anticipated debate between Biden and former President Donald Trump. For most Americans, it was their first extended and unscripted look at the candidates in this election cycle.

CNN’s Jake Tapper posed the evening’s first question, asking Biden, “What do you say to voters who feel they are worse off under your presidency than they were under President Trump?”

Subdued, and speaking in a soft and halting voice, an ill-appearing Biden struggled to construct a fluid response, identify words and complete his thoughts, a pattern that would continue throughout the 90-minute debate. Although the president seemed to perform a bit better toward the end of the evening, the sense that something was very much amiss permeated the event.

Predictably, post-debate analysis was dominated not by Trump’s frequent misrepresentation of established facts, or differences in the candidates’ policy positions, or their vision for the next four years, but rather by alarm over Biden’s health. Biden later told ABC that he “just had a really bad cold” on debate night and said he was distracted by Trump “still shouting” over his muted microphone while Biden was speaking.

With a combined age of 159 years, no presidential election in American history has featured older major-party candidates, and at no other time in the last half century has there been more concern about the physical and cognitive status of both candidates.

Despite his many years in the public eye, we still know very little about the health of 78-year-old Trump. Last November, Dr. Bruce Aronwald, Trump’s personal physician since 2021, issued a meager, three-paragraph, data-devoid note attesting to Trump’s physical and cognitive fitness for office.

In February, Biden’s White House physician, Dr. Kevin O’Connor, released a more comprehensive report, summarizing the president’s medical history and results from his annual checkup. The six-page document described the 81-year-old patient’s history of atrial fibrillation, sleep apnea, osteoarthritis, hyperlipidemia and peripheral neuropathy.

In a section describing an extensive assessment of the president’s noticeably stiff gait, O’Connor stated that Biden had undergone a thorough multidisciplinary evaluation, including an examination by a neurologist, that ruled out the presence of degenerative neurologic conditions such as Parkinson’s disease, multiple sclerosis and ALS. There was no report of a cognitive assessment.

While Medicare does cover cognitive screening examinations for adults 65 years and older, the United States Preventive Services Task Force (USPSTF) in 2020 reviewed the role of dementia screening examinations in asymptomatic adults in this age group and concluded that “the current evidence is insufficient to assess the balance of benefits and harms of screening for cognitive impairment in older adults.”

But Biden’s performance at last month’s debate raised questions about whether the president is truly asymptomatic, and whether he now shows signs of cognitive decline.

Deterioration in cognitive capacity is common with advancing age. Dementia, which is defined as a significant deterioration in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor control and social cognition) affects more than 10% (6 million people) 65 years old or above. Mild cognitive impairment occurs in another 22%.

While the USPSTF review is noncommittal on the use of dementia screening in ostensibly asymptomatic people, there’s no ambiguity in the use of testing in adults where dementia is a concern. There are a variety of screening exams such as the Montreal Cognitive Assessment (MOCA) or Mini-Mental State Examination that are used to detect signs of cognitive decline. If these tests are abnormal, extensive further assessments are performed, including a variety of laboratory studies, screening for depression and magnetic resonance imaging (MRI) of the brain.

Trump has repeatedly bragged that he “aced” two dementia screening tests during and after his presidency, and described the former test as “difficult”. But that exam (the MOCA test), which, among other questions, asks the patient to draw a clock, identify a camel and count backward from 100 by sevens, is a low bar for a candidate who, if elected, will carry nuclear launch codes.

There are only a few medical conditions that should disqualify a candidate from assuming the presidency, but dementia is certainly one. In view of Biden’s very public difficulty during the debate, America’s voters need to know whether the poor performance was simply a poorly timed, one-off event — a “bad night,” in Biden’s words — or whether it represents a degenerative process.

If indeed the president has not been recently tested for evidence of cognitive decline, it’s in the country’s best interest that the assessment be performed now. If the evaluation shows no evidence of impairment, this issue should be put to rest. If testing is abnormal, then both the patient and the country need to know.

It’s time to look.