Nurses who work shifts lasting more than 12 hours are at an increased risk of experiencing burnout, a new European study involving Irish nurses has found.

It also found that shifts lasting more than 12 hours are increasingly common in Ireland.

Burnout is characterised by emotional exhaustion, loss of purpose and depersonalisation - treating people as if they are objects. It can lead to personal issues such as depression and alcohol abuse, but may also impact patient care. It can also result in increased absenteeism and people leaving their jobs at an earlier stage than originally planned.

UK researchers surveyed over 31,600 nurses in 12 European countries, including Ireland, England, Germany, Poland, Finland and Sweden. The detailed survey looked at the demands of the job and the nurses were also assessed for burnout.

Most of the respondents were women and their average age was 38 years. Almost two in three worked in high-tech or teaching hospitals.

The study found that the most common shift length was eight or fewer hours (50%), followed by eight to 10 hours (31%). However it also found that shifts that lasted longer than 12 hours were more common in certain countries, including Ireland.

In fact, 79% of Irish respondents stated that they worked shifts of this length. Almost all respondents in Poland (99%) also admitted to working these long shifts, while 39% of respondents in England worked them.

The researchers found that overall, 27% of nurses reported high emotional exhaustion, 17% reported low personal accomplishment and 10% reported high levels of depersonalisation.

Around one in four of those surveyed said they were unsatisfied with their job and one-third said they planned to leave their current job.

Meanwhile, an analysis of the findings revealed that those working shifts longer than 12 hours were much more likely to show signs of burnout. For example, those working the longer shifts were 40% more likely to be dissatisfied with their jobs compared to those working eight hours or less.

"Current literature tends to report that 12-hour shifts represent a way to retain nurses in hospital clinical practice because it is believed to be the preferred shift length and that nurses are more satisfied with their jobs. Our results suggest the opposite. Therefore, our findings pose substantial questions for managers, most notably because job satisfaction is a consistent and robust predictor of remaining in a job," the researchers commented.

Details of these findings are published in the journal, BMJ Open.