Findings published this morning in the Occupational Health at Work journal show almost half (45%) of those returning to work experienced symptoms of depression but were worried about telling their employer.
The study showed while most line managers were initially supportive of staff returning to work, they were not aware of the longer-term effects of a serious physical condition on the mental health of staff and their ability to work.
Findings also revealed most occupational health and HR departments, as well as line managers, were adequately trained in dealing with psychological issues, and stress management was only offered to a quarter of staff experiencing depression.
Shorter working hours, fewer job tasks or reduced workload were beneficial to affected staff but those who did not receive such adjustments felt this was detrimental to their mental health and wellbeing.
Andrew McCullough, chief executive at the Mental Health Foundation, said: "It is sad many employers can deal better with life-threatening and frightening illnesses like cancer than mild to moderate depression, because of stigma and lack of information.
"While the need for change is clear, this report is not about knocking employers. It makes clear the need for improved training for managers and clear policies and procedures from HR."
Commenting on the findings, Susan Scott, chief executive of Employers' Forum on Disability, added: "Best practice on mental health at work is often about common-sense principles like mental health awareness training and using cost-free, good management techniques. Above all, adjustments need to have the support of both employees and employers to be a success."
Almost half of long term sick suffer from depression when they return to work
Staff returning to work after long-term illness are at risk of depression although managers are unaware, according to the Mental Health Foundation.