Causes of suicide not always straightforward

(CNN) - The reasons why people take their own lives aren't always clear, mental health experts say; a multitude of biological and psychological factors may be involved in how individuals respond to difficult circumstances in life.

The world may never know everything that contributed to the apparent suicide of Jacintha Saldanha, a nurse who took a prank call from Australian radio DJs pretending to be Queen Elizabeth II and Prince Charles.

Saldanha's name became public only after her death. She was found hanging from a wardrobe door at her hospital living quarters, a coroner's court in London heard Thursday. Saldanha left three notes; the contents were not made public.

She worked as a nurse at King Edward VII's Hospital, where Catherine, Duchess of Cambridge, was being treated last week for acute morning sickness. Saldanha put the call through to the ward where Prince William's wife was staying. A different nurse gave out information about Catherine's condition.

Even before Saldanha's death, the chief executive of the hospital, John Lofthouse, condemned the prank as "pretty deplorable." Her apparent suicide has sparked an international outcry.

"It's certainly possible, but it's not likely, that someone who never thought about suicide before, if there was something uniquely shaming or embarrassing or humiliating about this, that it just triggered them," said Nadine Kaslow, professor of psychology at the Emory University School of Medicine.

"What's more likely is that they might have thought about suicide at other times in their life," she said.

This wasn't just any prank. It was a public event, and a mistake that could have potentially gotten Saldanha in trouble, Kaslow said.

"You feel ashamed; you feel frightened," Kaslow said. "To think that you got the chance to talk to one of the royals, and then it turns out you talked to people who are from the radio station, you feel like a fool."

Intense emotions of guilt and shame are difficult for people to deal with, she said. A person in Saldanha's situation may have felt ashamed, thinking she had let her country down, or afraid of what the consequences would be.

A palace spokesman told CNN previously: "At no point did the palace complain to the hospital about the incident. On the contrary, we offered our full and heartfelt support to the nurses involved and hospital staff at all times."

There's not always a clear cause of suicide, experts say. Some people are more vulnerable than others to anxiety and depression, said Alan Manevitz, a family psychiatrist in New York.

"Some people have more natural resilience to stressors than others," Manevitz said.

Having a mental illness is a risk factor for suicide, but not everyone who takes their own life is mentally ill, Kaslow said. Sometimes a person who is already feeling stressed or fragile can be pushed to the brink with an incident like this.

"For other people, it's actually that they're doing OK, but a stressor has a unique power to them, and in that moment they just feel unable to cope or manage," Kaslow said.

Other risk factors for suicide include alcohol and substance abuse, family conflict, major loss, family history of suicide, physical illness and feelings of hopelessness and isolation. But there's still a lot that scientists don't know about why some people turn to suicide and others do not, even when facing the same traumatic incident.

No information has been released about whether Saldanha had any risk factors for suicide.

A stressor such as getting fired or not having enough money to pay a bill can be devastating to some people and less so for to others. Similarly, when a group of people suffers a traumatic event, not everyone will react in the same way. Some may take their own lives.

"Why some people get PTSD and some people don't and why some people become suicidal and some people don't may be based a combination of biological, psychological (factors) and ways that they react to stressors," Manevitz said. "It's not such a simple answer."

Nurse death sparks outrage, casts glare on 'shock jocks'

The unfortunate turn of events is an important reminder that pranks can be hurtful and result in tragic unintended consequences, Manevitz said.

"I think this is a world lesson for everyone about treating everyone with more sincerity and genuineness and straightforwardness, and we don't have to do everything just to entertain ourselves," Manevitz said.

Not everyone wants their 15 minutes of celebrity, especially when it's unexpected, Manevitz said. Media attention may create a lot of anxiety, as well.

The hospital said Saldanha had worked there for more than four years as an "excellent nurse," and that she was well-respected by coworkers. Classmates and colleagues in India, where she was from, described her as deeply religious, studious and benevolent.

"It's very sad that for whatever reason or reasons, this situation just felt so overwhelming to her that she felt there was no way to face the world," Kaslow said.

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