Patients admitted to hospital at weekends have a greater chance of dying than those admitted on a week day, a large-scale review of NHS data has reiterated.

They are 16 per cent more likely to die if they are admitted on a Sunday than a Wednesday, and 11 per cent more likely to die if they are admitted on a Saturday.

For every 100 deaths following admissions on a Wednesday, 116 occur for admissions on a Sunday - a “significant increased risk”, the researchers said.

It follows a report in November which found patients needing emergency care are almost 10 per cent more likely to die if they are admitted on weekends and are less likely to receive prompt treatment.

The new analysis covered all admissions - more than 14.2 million - to NHS hospitals in England during 2009/10, including both emergency and planned admissions.

It looked at more than 187,300 patient deaths within 30 days of being admitted to hospital.

The researchers found higher death rates if patients went in on a weekend but a slightly lower death rate if people were already in hospital on a weekend.

Being already in hospital on a Sunday led to an 8 per cent reduced risk of dying on that day compared to already being in hospital on a Wednesday.

The medical conditions resulting in the biggest number of in-hospital deaths included pneumonia, congestive heart failure, heart attack, septicaemia, acute renal failure, urinary tract infections and neck or hip fracture.

The experts, including from University College London and the Universities of Birmingham and East Anglia, wrote in the Journal of the Royal Society of Medicine (JRSM): “We identified a significantly higher risk of subsequent in-hospital death during the 30-day follow-up period associated with admission during the weekend (Saturday or Sunday), compared to midweek days.

“Admission on Tuesday through Friday was associated with the lowest risk of in-hospital death, while admission on Sunday was associated with the highest risk.

“Admission on Saturday was associated with a marked increased mortality risk and admission on Monday was associated with a less, but statistically significant, increased risk.”

Lead researcher Professor Domenico Pagano, from the University Hospital Birmingham Foundation Trust, added: “These results offer conclusive evidence that confirms previous reports of increased 30-day mortality risk for patients admitted to hospital with emergency conditions at the weekend compared with the rest of the week.”

He said several reasons may be behind the findings, including that patients who are seriously ill can find themselves admitted on weekends.

If they were less ill, they would have had their admissions postponed until a week day.

Professor Pagano also said reduced staffing and fewer senior doctors on duty as well as poor access to diagnostic tests on weekends could have an effect. The Department of Health is looking at ways the NHS could provide more services at the weekend, including more tests and consultant cover.

While this will not be imposed, tools such as providing financial incentives for trusts to promote weekend working and incentives for GPs to strike deals with hospitals which deliver care at weekends could be introduced.

As well as publishing data on outcomes for patients, hospitals may be rewarded a small bonus percentage of their income for offering care at weekends.