The US president has chronic venous insufficiency and shakes many hands, his doctor has said

The White House has released a memo from President Donald Trump's physician explaining recent visible changes in his limbs, which some observers had taken as indicators of a serious health condition.

In a memo issued Thursday, Dr. Sean P. Barbabella said Trump has been diagnosed with chronic venous insufficiency, a condition he described as "benign" and common among people over the age of 70.

Trump, 79, was recently seen with swelling in his legs, which Dr. Barbabella attributed to the condition. Chronic venous insufficiency is typically age-related and involves malfunctioning of one-way valves in the veins, which are responsible for returning blood to the heart.

The legs are often affected because the veins there must work harder against gravity. People who spend extended periods standing are more susceptible to the disorder.

According to the statement, no signs of more serious vascular conditions - such as deep vein thrombosis - were found. Barbabella also explained that recurring bruising on the back of Trump's right hand was the result of "soft tissue irritation from frequent handshaking" and preventive aspirin use.

While swelling in Trump's ankles gained attention last week, the bruises on his hand have been visible since at least October, fueling speculation that he was undergoing intravenous treatment. Trump and his staff have repeatedly said the marks are due to vigorous handshaking.

Many senior US officials are of advanced age. Critics argue that the country's political system favors seniority and has effectively turned into a gerontocracy.

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President Joe Biden's age became a major campaign issue during last year's presidential election. His aides were accused of hiding signs of cognitive decline to keep him in the race. Biden dropped out of the campaign less than four months before Election Day after a disastrous debate performance against Trump.