Jacqueline Bignell worked so hard she was "thrown into bed". At the peak of her work addiction five years ago, she was sleeping only one or two hours a night and working all waking hours in her film production company. "Ultimately, my body shut down and I came to a place where I could not work any more," she said. Each time she tried to restart, she'd soon be "working like a crazy woman" again and end up back in bed.

The 51-year-old from Toorak in Melbourne knew if she didn't stop she would end up dead. But telling a workaholic to stop is like telling a drug addict to give up drugs, or an alcoholic to turn away from the bottle. "Even though you know what you are doing is literally killing you, you can't put it down because of the obsession," she says.

The label "workaholic" is often used lightly, but it's no joke for people who genuinely suffer from a psychological addiction to work. A survey of more than 16,000 people in Norway finds workaholics are much more likely to have the psychiatric symptoms of ADHD, OCD, anxiety and depression.

"Workaholics scored higher on all the psychiatric symptoms than non-workaholics," says lead researcher Cecilie Schou Andreassen of the department of psychosocial science at the University of Bergen.

Nearly a third (32.7 per cent) of workaholics also meet the criteria for attention disorder, compared with 12.7 per cent of non-workaholics. About the same proportion (33.8 per cent) meet anxiety criteria, compared with 8.9 per cent of non-workaholics, and a quarter of workaholics also meet OCD criteria, the study, published in the open access journal PLOS One, finds.

"Thus, taking work to the extreme may be a sign of deeper psychological or emotional issues," Ms Schou Andreassen says. "Whether this reflects overlapping genetic vulnerabilities, disorders leading to workaholism or, conversely, workaholism causing such disorders, remain uncertain."

Jasmine Sliger, a cross-cultural, organisational and counselling psychologist, cautions that the study's  validity in Australia may be limited due to cultural differences with Norway. For example, participants in Norway's collectivist, task-oriented, persevering work culture may have a lower bar for workaholism compared with workers in Australia, where the focus is on individual performance and quick results.

Workaholism is defined as being driven by an uncontrollable work motivation and feeling compelled to invest so much time, effort and concern in work that other areas of life are impaired. The rise of globalism and the blurring of lines between work and home allowed by digital devices has led to fears it is on the rise.

"The pressure on people in the workplace today is really increasing," says Ms Sliger of JSA International Communications, whose clients include large corporations and high-flying individuals, such as barristers, lawyers, surgeons and psychiatrists, most of them male.

She says there is "absolutely no question" that workaholics are at risk of mental health issues, including depression. When a client presents with workaholic symptoms, she looks for signs of anxiety, depression or obsessional thinking.

The study classifies 7.8 per cent of respondents as workaholics; other studies estimate between 5 per cent and 25 per cent of workers suffer from the condition. Several studies have suggested workaholism is more prevalent among people with higher education and management duties, in certain lines of work including agriculture, trade, medicine and communications, in the private sector and among self-employed people.

In the Norwegian study, those most likely to meet the workaholic criteria are younger, female, not in a relationship, managers, self-employed and meet clinical criteria for ADHD, OCD, anxiety and depression. The researchers suggest targeting interventions to prevent workaholism at people with these characteristics.

The researchers admit that, because of the very large sample size, "some trivial relationships may have turned out significant".

Ms Bignell considers herself in recovery from workaholism. Her single status is one of the costs of her workaholism.

"I'm 51, single, never married. In retrospect, I can look upon my life and say: 'How ever was I supposed to meet someone when I was always busy and working?'"

She continues to work on filmmaking, and will soon launch a Work Addiction Institute to inform and educate individuals and corporations about workaholism.

Help is available from Workaholics Anonymous: 0400 885 592