A LANDMARK study into excess patient deaths across NHS hospitals has found a “very clear and consistent” link between nurse staffing and patient mortality — and that replacing them with lower-paid workers makes no difference.

Dramatic variations in patient death rates were revealed in the first-ever analysis of staffing and death rates over time, sparking calls for NHS England to investigate trusts where deaths have risen.

Study leader Professor Alison Leary told the Sunday Times that the data across 122 NHS trusts over four years showed “a very clear and consistent relationship between the absence of registered nurses available to patients and excess deaths.”

“Although organisations have tried to make up for the lack of registered nurses with other staffing groups, this has not improved survival,” added the chair of workforce modelling at London South Bank University and a senior consultant for the World Health Organisation.

The study, covering December 2020 to May 2024, found that hospitals with lower-than-expected death rates had the highest nurse staffing, with an average of 5.65 hours of registered nurse care per patient per day.

Those with higher-than-expected deaths meanwhile had significantly fewer nurses available to care for patients, with just 4.59 hours of nurse care per patient per day.

The research suggests that to reduce excess deaths in hospitals, trusts would need to target an average of at least 5.5 hours of registered nurse care per patient per day. Currently, many operate at less than five hours of nursing care per patient per day.

NHS trusts found to have the highest excess deaths included East Cheshire, Co Durham and Darlington, University Hospitals Plymouth and East Lancashire Hospitals.

The best-performing trusts included University College London Hospitals, Kingston and Richmond, Royal Surrey, Imperial College Healthcare and Chelsea and Westminster Hospital.

Royal College of Nursing chief executive Prof Nicola Ranger said that, given the strength of the data, NHS England should investigate trusts with high death rates, warning that nurses were being left responsible for a “shockingly unsafe” 16 patients.

She threatened strikes if ministers fail to recognise the value of nurses, as well as other industrial action including working to rule and even legal action on equality grounds. Nine in 10 nurses are women, with most ethnic minorities workers on the lowest pay grade.

Keep Our NHS Public co-chair Dr John Puntis told the Morning Star: “The findings of this powerful study add weight to the extensive data that already exists showing a link between lower staffing levels and increased risk of patient death and adverse outcomes.

“Compared with comparable European countries, the NHS remains underfunded, understaffed and with too few beds. 

“Lack of community and social care support, effectively delaying both discharge from hospital and admission of sick patients from emergency departments to overcrowded wards, already accounts for 16,600 avoidable deaths each year. 

“Current financial restrictions are putting tens of thousands of clinical posts at risk as trusts attempt to balance the books. 

“Rather than the future envisaged in the Long Term Plan for Health of fewer staff, artificial intelligence replacing skilled workers and fundamental shifts in care without commensurate funding, this study is a clarion call to those in power to look hard at the evidence and think again.”

Hospitals have lost 1,936 nurses and 4,240 support staff such as healthcare assistants in this financial year despite the NHS having a £29 billion cash increase to 2029.

A Department of Health spokesman said: “The government hugely values the work of talented nurses and recognises the massive contribution they make to our NHS. Since coming into office, we have awarded nursing staff two above-inflation pay rises, meaning new full-time nurses will now earn over £30,000 for the first time.

“We are determined to ensure scandals of the past are not repeated, and our 10-year workforce plan will deliver a transformed NHS so it has the right people in the right places, with the right skills to care for patients.”

The study is to be published in the Journal of Patient Safety and Risk Management.