President Joe Biden arrived at a recent public event with visible CPAP strap lines on his face.

On Wednesday, the 46th and incumbent president of the United States spoke at a healthcare event at the White House.

Photos of Biden snapped during the event showed strap line markings on his cheeks from undergoing CPAP therapy for his sleep apnea.

RELATED: Joe Biden Is 'Healthy, Active, Robust' And 'Fit For Duty' As Oldest US President, White House Doctor Says

President Joe Biden
U.S. President Joe Biden delivers remarks about his administration's work to lower the cost of breathing treatments for asthma and COPD patients during an event with healthcare advocates and stakeholders in the Indian Treaty Room in the Eisenhower Executive Office Building on April 03, 2024 in Washington, DC.
(Photo : Chip Somodevilla/Getty Images)

A continuous positive airway pressure (CPAP) is a machine that is commonly prescribed for patients with sleep apnea disorders, according to Healthline.

To keep a sleep apnea patient's airways open, the CPAP sends a steady flow of pressurized air into the nose and mouth while they are asleep.

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The machine mainly comprises a motor housed in a base unit, a cushioned mask and a tube that connects them. It also has a headgear frame, "elbow" pieces that serve as joints and adjustable straps.

In 2023, Biden disclosed that he had begun using the CPAP to aid with his longstanding sleep apnea. He first revealed his condition ahead of the 2008 presidential campaign, according to Bloomberg.

Meanwhile, in 2019, the Department of Medicine released Biden's medical and surgical history from when Kevin C. O'Connor was assigned as his primary care physician. 

"Obstructive Sleep Apnea (OSA) has been considered, but his symptoms have improved significantly after his sinus and nasal passage surgeries," the document read.

Sleep apnea is "a potentially serious sleep disorder in which breathing repeatedly stops and starts," according to the Mayo Clinic.

One of its main types, OSA, is the more common type and happens when the throat muscles relax and block airflow into the lungs.


President Biden Delivers Remarks At The White House
WASHINGTON, DC - AUGUST 24: U.S. President Joe Biden gestures after being asked how much advanced notice he received from the FBI regarding the search warrant at Mar-a-Lago, after speaks on student loan debt in the Roosevelt Room of the White House August 24, 2022 in Washington, DC.
(Photo : Photo by Alex Wong/Getty Images)

Biden is the oldest U.S. president to ever hold the office. He is currently 81 years old. But despite his age and sleep apnea, he was considered "fit for duty" in a report released by the White House last month.

"The President feels well, and this year's physical identified no new concerns. He continues to be fit for duty and fully excuses all his responsibilities without any exemptions or accommodations," the report summary read.

The report also stated that Biden had "demonstrated excellent response to PAP and is diligently compliant with therapy" regarding his OSA.