The family of Luigi Mangione, the suspect in the Dec. 4 murder of UnitedHealthcare CEO Brian Thompson, reported him missing in November after he withdrew from social contact following back surgery.

Mangione, 26, was reported missing on November 18, police told the New York Post, after family members feared they had lost contact with him. A message had previously been distributed from relatives to his circle of friends asking for help in the search after Mangione had undergone back surgery a few months earlier.

Late Monday, Mangione was charged by New York prosecutors with murder and other charges in connection with the brazen killing of the UnitedHealthcare CEO on a midtown Manhattan street. After a manhunt lasting several days, he was arrested at a McDonald’s in Altoona, Pennsylvania, after he was recognized by a local person in photos released by police.

He is being held without bail in Pennsylvania before being extradited to New York, which could come as soon as Tuesday.

As the investigators begin to reconstruct the suspect’s story, one of the issues discussed is the chronic back problems that he appears to have suffered from since childhood. According to CNN, Reddit posts matching Mangione’s description talked about struggling with spondylolisthesis, a condition in which a vertebra, often in the lower back, slips out of place.

The condition got significantly worse after a surfing accident, said the Reddit user. “My back and hips were locked after the accident,” the user said, causing “temporary numbness” that left him “scared of the consequences.”

The owner of Surfbreak, a condominium in Honolulu, Hawaii, where Mangione lived for several months, told CNN that Mangione had been suffering from back pain that could force him to stay in bed for days. “It was really traumatic and difficult when you’re in your early 20s and you can’t do some basic things,” RJ Martin said.

After the surgery, Mangione sent a text message with X-rays, Martin said. “It looked hideous, with just huge screws in its spine,” he said.

Mangione had alluded to his ongoing health struggles on his social media feeds. As a banner for his X account, he posted a picture of a person after a spinal fusion.

His reading list on Goodreads included five books on dealing with chronic back pain, including Crooked: Outwitting the Back Pain Industry and Getting on the Road to Recovery.

According to a Wall Street Journal report, Mangione’s withdrawal from social media appears to have begun several months ago. A friend raised concerns on social media in July, saying, “I don’t know if you’re fine or if you just live in a super isolated place… but I haven’t heard from you in months.”

Another friend’s post from October said: “No one has heard from you in months and it seems your family is looking for you.”

The suspect comes from a wealthy family in Baltimore, Maryland, that owns a real estate portfolio, nursing homes and a local radio station. He attended the best schools in Baltimore and the Ivy League University of Pennsylvania.

So far, his family has not commented on Mangione’s apparent disappearance or his back problems. A statement after the shooting said: “Our family is shocked and devastated by Luigi’s arrest. We pray for Brian Thompson’s family and ask people to pray for everyone involved.”

Mangione appeared in court for the first time Monday night to face charges related to Thompson’s killing before the annual UnitedHealthcare investor meeting in New York. In addition to the murder charge, he is also charged with criminal possession of a weapon and a silencer.

Police said they arrested him in possession of a so-called ghost gun – which may have been made from a 3D printer – and a silencer.

Mangione remained largely silent during the trial, although he did speak out to dispute the account presented by prosecutors. They said he was carrying about $10,000 cash and claimed that the bag he was carrying could block cell phone signals, all pointing to his sophisticated criminal plans.

“I want to correct two things,” Mangione said, according to CNN. “Firstly, I don’t know where the money came from – I’m not sure it was planted. And besides, that bag was waterproof, so I don’t know anything about criminal sophistication.”