President Joe Biden's declining physical and mental health has been an issue for a while, but there are indications that his deterioration has recently grown markedly worse.

The elderly president was described last week as "visibly shaking" and struggling to exit Air Force One and enter a waiting SUV following his farewell speech at the Democratic National Convention, according to the Daily Wire.

That incident follows closely on the heels of separate but related speculative reports last month that Biden may be suffering from a neurological disorder and that first lady Jill Biden has assumed a sort of caretaker role for her husband and his presidency.

Biden's post-convention speech struggles

Last Monday, according to the Daily Mail's senior White House correspondent Emily Goodin, President Biden delivered a speech near the end of the first night of the Democratic convention -- a speech that was pushed back past primetime because of a crowded schedule that also resulted in a special video tribute for Biden and a special performance by James Taylor being cut.

Biden's speech didn't conclude until after midnight Eastern Time, and after leaving the convention and boarding Air Force One for a flight to California with his family for a vacation at a billionaire donor's ranch near Santa Barbara, it was nearly 5:30 am ET when the presidential jet arrived at its destination and Biden had reportedly been awake for nearly 24 hours.

"Walking slowly down the plane's stairs, he struggled to step up into the SUV waiting to take him to the 8,000-acre Santa Barbara ranch where he and his family have just enjoyed a week-long vacation," Goodin wrote. "One of his Secret Service agents moved to shield him from the watching cameras, before giving him a helpful boost into the car."

"On the tarmac, First Lady Jill Biden watched, visibly concerned," the reporter continued. "For her husband -- who dropped out of the election race almost a month ago to the date -- had just ended his exhausting journey from Democratic nominee to lame-duck president."

Goodin noted how the packed DNC schedule not only pushed back Biden's speech but also seemingly truncated the introductory remarks of his wife Jill and daughter Ashley, and how the Biden family immediately left Chicago after the president finished, and added, "Far from extraordinary, however, that image of Biden, shaking with exhaustion as he left Air Force One and after his own party had humiliated him on the global stage, was one of just many behind-the-scenes dramas in a week so fraught with party infighting that it began to resemble a Shakespearean tragedy."

Biden exhibiting symptoms of Parkinson's disease

About a month and a half earlier, in the aftermath of President Biden's disastrous debate performance in late June but before he was essentially ousted from his position as the Democratic nominee by his own party, speculation grew about the increasingly obvious signs of his deteriorating physical and mental condition, per the Daily Wire.

Speaking to NBC News, New York City board-certified neurologist Dr. Tom Pitts, who acknowledged that he hadn't personally examined the elderly president, diagnosed him from afar as "definitely" suffering the degenerative effects of Parkinson's disease, as he observes similar symptoms and traits "20 times a day in clinic" with other patients in terms of how they speak and walk and interact with others.

"Shuffling gait, we call that 'little steps.' Loss of arm swing from the rigidity; when we walk we have a nice cadence, he doesn’t really swing his arms, and end-block turning, meaning he kind of pivots around his foot," Pitts said of Biden. "It’s one of the easier movement disorders to diagnose. I’m a Democrat … This guy is not a hard case. … once you start manifesting the hallmark motor symptoms, slow movement, rigidity, masked facies, hypophonia -- if a med student did not pick Parkinson’s on the test, they’d be remediated."

"His motor symptoms are degenerating," the doctor added. "He has Parkinsonisms. That is a fact. He has degeneration of the brain. Show me the MRI. Show me he doesn’t. Put your money where your mouth is. He definitely has it."

Edith Wilson redux?

President Biden's deterioration has also given rise to comparisons to one of his predecessors just over a century earlier, former President Woodrow Wilson, who was incapacitated by a stroke and largely bedridden for his final year in office, which reportedly led to then-first lady Edith Wilson effectively seizing the reins of the government on her husband's behalf and serving as the acting president in his stead.

A Boston Herald op-ed in early July wondered if first lady Jill Biden hadn't essentially done the same thing and, perhaps jokingly, suggested that the president step aside and allow his wife to be the Democratic nominee, given that her apparent role "as the president’s hovering caretaker and advisor have become Edith Wilson-like. Biden can barely walk or talk without her at his side."