The NHS is failing to meet treatment targets and the rate of slippage has reached levels as bad as the 'early 1990s' the author of a report from the King's Fund told the BBC.
The report also noted that an £800m overspend has occurred as NHS funding has increased 0.8% annually in real terms.
Among the NHS staff polled, 38% have reported they felt unwell due to stress, the report The NHS under the coalition government - Part two: NHS performance found.
More patients were waiting longer than 18 weeks for treatment with 11% of inpatients and 5% of outpatients waiting over that time in January 2015 compared to 7% and 2% in May 2010.
The NHS has missed some cancer waiting time targets while occupancy rates for hospitals increased and one in six trusts reported levels above 95%.
The report also found that the number of NHS doctors and nurses have increased, with 2.3% more nurses the equivalent to 7,049 full time posts having been added.
There were also 16% more consultants equivalent to 6,814 full time posts and 0.6% more GPs, equivalent to 209 full time posts.
The number of NHS management staff fell by 16%, the equivalent of 6,814 full time staff.
MRSA and C difficile infections have fallen with 34 and 445 cases respectively in January 2015 compared to 59 and 1,019 in May 2010.
John Appleby, chief economist at The King's Fund and lead author of the report, said: "The next government will inherit a health service that has run out of money and is operating at the very edge of its limits.
"While the NHS has performed well in the face of huge challenges, there is now a real risk that patient care will deteriorate as service and financial pressures become overwhelming.
"More optimistically, with the economy recovering, there could soon be an opportunity to think about public spending choices and the kind of health services we want in a fresh light.
"Future debate about the NHS should focus not on how parsimonious we need to be but on how generous we want to be."
Dr Mark Porter, council chair at the British Medical Association said: "This report highlights the damage done to the NHS by the Health and Social Care 2012, which distracted attention from rising pressure on services and cost billions to introduce.
He added: "The NHS is the best health care system in the world, and the most efficient - there is no fat left to cut without patient care being hit."
