[attach id=244282 size="medium"]The mindset of mugging victims may become more like that of a bodyguard, vigilant for danger.[/attach]

Victims of muggings and assaults are left with persistent feelings of paranoia that can affect their relationships with others, research has shown.

Two-thirds of those taking part in a study remained “excessively fearful” of people around them for at least six months. The feelings of wariness and distrust were distinct from symptoms of post-traumatic stress disorder (PTSD), which affected 16 per cent of participants.

Victims’ paranoia was especially pronounced if they had been attacked by someone they knew, and even transferred to computer-generated characters in a psychological test.

Scientists studied 79 men and 27 women with an average age of 34 who had attended a London hospital’s casualty department for treatment after an assault.

The injuries, which ranged from cuts and bruises to broken bones, head wounds and damage to internal organs were mostly the result of confrontations, random attacks and muggings.

Domestic assaults resulting from ongoing abuse were not part of the study but one-off attacks by relatives, friends or work colleagues were included.

If we are attacked in places or by people we know, that leads to greater mistrust than being attacked by a stranger or in unfamiliar places

Four weeks after attending hospital, 80 per cent of victims reported feelings of excessive fear. Further assessments were conducted at three and six months, and over time this figure fell to 66 per cent.

Two-thirds of participants said they had become fearful of all males after their assault, and half reported having the same feelings about females. One in 10 suffered very high levels of paranoia.

Study leader Daniel Freeman, from Oxford University, said: “It is very understandable that being attacked makes us wary of the people around us. Our mindset may become more like that of a bodyguard, vigilant for danger. When we are overly mistrustful, that is a form of paranoia. It may well be a normal temporary change in our thinking after being a victim of attack.

“The danger of such thoughts, however, is if we isolate ourselves, close off from others, and spend our time thinking only of the worst. It is an under-recognised problem in the aftermath of an attack.”

The researchers assessed paranoia in a number of ways, including self-reporting, interviews by trained specialists, and a virtual reality test in which victims reacted to computer-generated representations of people.

Their findings are reported in the journal Psychological Medicine.

Although for many victims the fear gradually eased with time, the team identified several factors during and after the assault that made it much more likely for feelings of paranoia to continue.

“If we are attacked in places or by people we know, that leads to greater mistrust than being attacked by a stranger or in unfamiliar places,” Freeman added.

“The trust we had becomes broken. If during the assault we feel destroyed as a person or we become detached from ourselves then mistrust typically stays for longer.

“Afterwards if we feel down on ourselves, ruminate and worry, and start to take excessive precautions, then fears will stay in mind. Conversely, it looks likely that we benefit from good sleep and feeling supported by those around us.

“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. However, fears about other people may actually be typical. And paranoid thoughts are much more likely to remain depending upon how we respond both during and after the attack. We plan to use this information to improve the latest generation of cognitive behaviour therapies for those seeking help.”

Anke Ehlers, a PTSD expert at Oxford University, said: “During the last decade, significant progress has been made in understanding the factors that predict who will develop PTSD after assault, and this has helped improve the effectiveness of psychological treatments. The finding that many of these factors also predict paranoia opens up new avenues for treatment.”