Opinion | The Struggles of President Biden and the Truth About Aging

Last week, President Biden tried to acknowledge and mitigate concerns about his capacity to stay on in the most important job in the world. “I know I’m not a young man, to state the obvious,” he said after a disastrous debate against Donald Trump. “I don’t walk as easy as I used to. I don’t speak as smoothly as I used to. I don’t debate as well as I used to.” But, the president went on, “I know, like millions of Americans know, when you get knocked down, you get back up.”

He was asking Americans to see themselves in him and to recognize his debate performance as both an aberration from and a continuation of who he has always been: a person who may suffer and stumble but whose ambition, commitment and confidence in himself have provided a backstop of resilience against insult and injury.

Reporters and Mr. Biden’s biographers have been reflecting over the past week about the severity and nature of his condition and on whether they missed signs or were duped. Americans are suddenly engaged in a speculative conversation about whether the President is physically and mentally fit to lead the country and whether they can trust his self-assessment. What would it mean for a person to “get back up” who also can’t walk, speak or debate with the ease he once did? And how to make sense of his appearance at the debate and the stories that have emerged since about lapses of memory, naps during the day and occasional bouts of confusion?

I’m a geriatrician, a physician whose specialty is the care of older adults. I watched the debate and saw what other viewers saw: a president valiantly trying to stand up for his record and for his nation but who seemed to have declined precipitously since the State of the Union address he gave only a few months earlier.

As a country, we are not having a complete or accurate discussion of age-related debility. I know no specifics — and won’t speculate here — about Mr. Biden’s clinical circumstances. But in the face of so much confused conjecture, I think it’s important to untangle some of the misunderstanding around what age-related decline may portend. Doing so requires understanding a well-characterized but underrecognized concept: clinical frailty.

As we age, everyone accumulates wear and tear, illness and stress. We can all expect to occasionally lose a night’s sleep, struggle with jet lag, catch a virus, trip and fall or experience side effects from medication. But for young and middle-aged people who are not chronically or seriously ill, these types of insults don’t usually change the way we function in the long term. This is not so for frail elders.