• Joe Biden is fit to continue his presidential responsibilities "without any exemptions or accommodations," the White House physician said.
• Biden is grappling with concerns about whether he is physically and mentally capable of serving another four years in the White House.
• The Democrat's age and fitness have become key attack lines from his political opponents, especially Republican presidential front-runner Donald Trump.

Joe Biden is fit to continue his presidential responsibilities "without any exemptions or accommodations," the White House physician said Wednesday after conducting the president's annual physical.

Biden "is a healthy, active, robust 81-year-old male, who remains fit to successfully execute the duties of the Presidency," Dr. Kevin O'Connor said in a summary of the president's health.

The results of the routine examination carry extra significance this year, as Biden seeks to tamp down concerns about whether he is physically and mentally capable of serving another four years in the White House.

The Democrat has weathered relentless attacks about his age and fitness from his political opponents, especially Republican presidential front-runner Donald Trump, who will turn 78 in June.

Despite their closeness in age, polls show voters are less concerned about Trump's fitness than Biden's.

Earlier in February, a Department of Justice special counsel investigating Biden over his handling of classified documents described the president in a report as an "elderly man with a poor memory."

Biden angrily pushed back on that report, acknowledging his age but declaring, "I know what the hell I'm doing."

Wednesday's six-page medical summary did not delve into Biden's mental acuity, but O'Connor reported that Biden's medical considerations "remain stable and well-controlled."

Biden takes six medications — three prescription, three over the counter — to deal with sleep apnea, atrial fibrillation, hyperlipidemia, gastroesophageal reflux, seasonal allergies, sensory peripheral neuropathy of the feet and spinal arthritis, which is linked to a stiffened gait.

But his physical exam is "essentially unchanged from baseline," O'Connor wrote.

The doctor also noted, "The President has been happily married for 46 years. He does not use any tobacco products, does not drink alcohol, and he continues to work out at least five days per week."

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