Vast swathes of German office space now stand empty

According to the research, by a German health insurance firm, cases of depression among Berliners have risen by 70% since 1997.

Up to 70% of Germans also say they are prepared to seek professional help for psychological problems.

Mental health experts blamed the rise on Germany's faltering economy, which has seen unemployment rise to over 5m.

German insurance firm DAK surveyed 2.6m employed Germans in an effort to discover the impact depression is having on modern working patterns.

How will someone ever get better when they know their boss is just waiting to fire them? Burghard Klopp Charité Hospital, Berlin

Among the respondents were 90,000 people working in Berlin, where treatment is widely available.

In contrast, fewer people reported feeling low in Germany's eastern states, where jobs and security are increasingly scarce, but mental health treatment is rarer and some taboos still exist.

Vicious circle

Workers in Germany's capital, regarded as one of Europe's most vibrant modern cities, emerged as an unhappy bunch more likely to miss work through depression than for any other reason.

Nationally, mental health problems were the fourth most common cause of absence from work, behind back pain, colds and flu and personal injury.

"In times of economic insecurity, young people in particular tend to develop psychological problems in response to professional and private obstacles," said DAK's Chief Executive Herbert Rebscher.

The report also blames modern working culture for the rise, especially among young people, although increasing numbers of elderly Germans also say they suffer from some form of psychological illness.

Psychological problems in men between 25 and 29 and women between 20 and 24 have doubled, the DAK reports says.

Nevertheless, most respondents said they would rather be depressed with a job than unemployed and happy.