Researchers have found that muggings can have lasting effects, including paranoia and PTSD, highlighting the importance of mental health services for victims of violent crime.

Chris Bjerre was heading home in San Francisco when he was robbed and assaulted.

The 29-year-old motion graphics designer was checking his phone on the bus when someone ripped it from his hands and made for the exit. A group of people helping the thief stopped him and tried taking his wallet before it got a little weird: a woman in the group used her three children as a barrier to keep Bjerre from getting his phone back.

After following the thief off the bus, Bjerre was repeatedly punched in the face before the group of assailants left. No one on the bus or at the bus stop stepped in to help Bjerre during the altercation.

Besides the immediate financial and physical consequences of being mugged, new research says that crime victims may experience paranoia, anxiety, and PTSD symptoms for up to six months, highlighting the importance of counseling for victims of violent crime.

While it’s well known that being physically assaulted can lead to post-traumatic stress disorder (PTSD), researchers recently investigated the effects of paranoia following an attack.

Researchers at King’s College London tracked 106 victims of violent crimes who were treated for minor injuries after being mugged. Their findings were published Tuesday in the journal Psychological Medicine.

Researchers found that a third of the victims experienced symptoms of PTSD and 80 percent were fearful of other people initially after the event, but those numbers were significantly lower a month later. Still, two thirds of the victims experienced symptoms of paranoia for up to six months after the event.

Paranoia is defined as an excessive mistrust of others, and researchers found that four out of five victims became more fearful of other people after being mugged. That excessive mistrust lasted for months.

While some fears are normal, researchers are worried about the added ill effects paranoia can have on a victim of violent crime.

Lead researcher Prof. Daniel Freeman of the University of Oxford said it’s normal for violent crime victims to be wary of others, but the transition to paranoia can lead to isolation and too much time dedicated to dwelling on the worst.

“Traditionally, it was thought paranoid thinking was rare in the aftermath of an attack. It was thought that paranoia only occurred in severe cases of PTSD,” Freeman said in a press release. “However, fears about other people may well actually be typical.

If you have been attacked, these sorts of thoughts are to be expected. And paranoid thoughts are much more likely to remain depending upon how we respond both during and after the attack,” he added. “We plan to use this information to improve the latest generation of cognitive behavior therapies for those seeking help.”

Researchers pinpointed several factors that can increase a person’s likelihood of developing paranoia after being mugged. They include:

  • being attacked close to home
  • feeling defeated at the time
  • worrying excessively afterwards
  • feeling unsupported by others
  • having difficulty sleeping

Being the victim of a violent crime can have a profound effect on a person’s mental health and well-being. Besides losing valuables, some people are robbed of the joy and feeling of safety they once held dear.

Support groups, counseling, and short-term use of antidepressants, anti-anxiety drugs, and sleep aids can help a person through the difficulty of being victimized. However, some people turn to self-medication through alcohol and drugs, but don’t treat the underlying causes of their anxiety and often create more problems than they solve.

Now, two weeks after being mugged, Bjerre said the incident hasn’t affected him much, other than making him more aware of his surroundings. He said he wouldn’t consider his feelings paranoid.

“I’m a lot more careful about just pulling my phone out and not sitting next to anyone suspicious, as bad as that sounds,” he said. “And also the fact that I know that other people are not going to help me if somebody jumps me.”