Feedback to freedom of information requests submitted to NHS organisations by the Observer show that there have been increases in the number of nurses taking stress-related leave in the past three years in London, Scotland and Wales.
The findings have provoked claims by health unions that the NHS's 400,000 nurses are stressed as a result of demanding and longer shifts amid pressures from understaffing and the increasing complexities of illnesses.
Tessa Jowell, former labour cabinet minister, believed this to be a result of the NHS "failing to provide necessary 24-hour services, as well as care in the community and in people's homes".
It is estimated that more than 30% of sick leave is stress orientated costing the NHS up to £400m a year in staff replacements and lost productivity.
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