New figures show that more hospital doctors in England and Wales are choosing to take early retirement and the number retiring for reasons of ill health has increased.
The number choosing to claim their pension ahead of retirement age more than doubled between 2008 and 2018, according to data obtained by journal The BMJ.
The British Medical Association (BMA) described the numbers as "the tip of the iceberg" and called for urgent action to address the problem.
The number of hospital doctors claiming their National Health Service pension on voluntary early retirement grounds rose from 164 in 2008 to 397 in 2018, the figures show.
Across the same period, the number retiring for reasons of ill health increased from 12 to 79.
The data also shows a greater proportion of doctors claimed pensions for these reasons.
In 2008, 14 per cent of hospital doctors claiming an NHS pension took voluntary early retirement, compared to 27 per cent in 2018.
Meanwhile, 1 per cent of retirements in 2008 were on the grounds of ill health, compared to 5 per cent in 2018.
The data was provided by the NHS Business Services Authority in response to a Freedom of Information request by The BMJ.
Dr Rob Harwood, chairman of BMA consultants committee, said: "These figures are concerning but certainly not surprising for doctors working in understaffed and under-resourced hospitals across the country.
"Given the combined pressures of mounting demand, unmanageable workloads and widespread gaps in rotas, it is to be expected that doctors may ultimately choose to leave the profession early.
"What is most worrying, however, is the six-fold rise in those retiring early due to ill health, clearly illustrating the effect these pressures are having on the physical and mental wellbeing of doctors, with many finding themselves at high risk of stress and burnout.
"No patient should be treated by a sick doctor, so ministers and policymakers must improve working conditions across the NHS, properly planning rotas to avoid understaffing and prevent unsafe situations."
The BMJ previously reported the number of GPs claiming NHS pensions on voluntary early retirement grounds increased from 198 in 2007-08 to 721 in 2016-17.
Australian Associated Press