Researchers from the AOK insurance group reviewed records from 9.7 million workers, and found that mental health issues such as depression were responsible for the longest periods of sick leave, the daily Süddeutsche Zeitung reported.
“With a respiratory infection a worker is gone an average of 6.5 days, but a psychological ailment is about 23 days,” the study's co-editor Helmut Schröder told the paper.
Complaints of psychological stress are the fourth most frequent reason workers take sick days, the study found. Some 8.6 percent of sick days taken by the AOK insured in 2009 were attributed to this – up from 8.3 percent the year before.
Psychological problems are also the biggest reason for early retirement, AOK found. In 2007, one-third of Germans who left the work force before legal retirement age blamed ongoing depression or a psychological disorder.
According to the National Statistics Office (Destatis), depression cost the country some €26.7 million in 2006.