More than 10 million people could be affected by an unhealthy relationship with their work, according to a new study completed by WIdO, the scientific institute of the AOK statutory health insurer.

Employees who often put off things in their personal lives for the sake of their jobs, work on Sundays or do extensive overtime, are more likely to have psychological problems, says the report. Overall, one in every five workers feels exhausted or unable to turn off while not at work.

“Flexibility needs clear barriers,” said AOK board manager Uke Deh.

“Employees who are constantly reachable, who always work at their upper limit, who can’t separate their career and their leisure time or who have long commutes are subject to a large amount of psychological strain,” said study editor Helmut Schröder.

Half of Germany’s 37 million employees are reachable outside of office hours and more than a third of them frequently work overtime or receive phone calls or emails after work.

More than one in ten take their work home with them and almost one in eight admits having a problem squaring the demands of work with their leisure time.

A growing number of commuters travelling longer distances are also cause for concern. The study says are 20 percent of them more likely to take official sick leave than non-commuters.

The Federal Office for Statistics said 12 percent of employees commute between 25 and 50 kilometres to work, with 4 percent travelling over 50 kilometres.

The authors of the study see these as central factors in the ever-growing prevalence of psychological illness. The number of cases has increased by 120 percent since 1994.

In 2011 around 130,000 people were granted sick leave by a doctor due to burn-out syndrome, whereas the number of sick days taken – 2,7 million – is eleven times higher than the figure seven years ago.

The AOK has called for bosses to make work in the changing technological landscape more bearable for their employees: “Keep work as predictable as possible, easy to plan, so that it makes sense.” Antje Ducki, co-editor of the report.

The good news is that an increasing number of employees identify themselves more strongly with their work and projects, whereas self-employed freelancers are becoming the prototype of professional life. The problem is that they “work themselves far beyond their own limits,” said Ducki.

The government is working on a new preventative healthcare strategy, which will focus on burn-out syndrome.

DPA/The Local/jlb