Between administering medications and coordinating care, nurses are some of the busiest health care professionals, often placed as the first point of contact for patients. Perhaps it comes as no surprise, then, that a recent study suggests patients are more likely to die after common surgeries when the nurses who care for them have heavier workloads.

Results of the study are published in The Lancet, where researchers from nine European countries report on data derived from over 420,000 patients in 300 hospitals.

They say that for every extra patient added to a nurse’s average workload, the chance of surgical patients dying within 30 days of admission increases by 7%.

However, they also found that a 10% increase in the ratio of nurses who hold a bachelor degree is linked to a 7% decrease in the risk of death.

To conduct their study, the team evaluated responses from more than 26,500 nurses and reviewed medical records for the hundreds of thousands of patients aged 50 years or older who were discharged after common surgeries, such as hip/knee replacements, appendectomy, gall bladder surgery and vascular procedures.

Their investigation took into account each patient’s risk of death and included age, sex, type of surgery, type of admission and the presence of certain chronic conditions. In addition, the team considered hospital characteristics, such as bed size, teaching status and technology.

Lead researcher Prof. Linda Aiken, from the University of Pennsylvania School of Nursing in the US, says:

Our findings emphasize the risk to patients that could emerge in response to nurse staffing cuts under recent austerity measures, and suggest that an increased emphasis on bachelor’s education for nurses could reduce hospital deaths.”

In detail, the report shows that the overall percentage of patients who died in the hospital within 30 days of admission was low, between an average of 1.0-1.5%.

But this percentage varied from hospital to hospital and ranged from less than 1% to more than 7%, the researchers say.

Additionally, nurse workload and education levels differ among countries. For example, the average patient-to-nurse ratio in Spain was 12:7, whereas in Norway this was 5:2.

In terms of education, all nurses in Spain and Norway had a bachelor’s degree, compared with an average of only 10% in Switzerland. In England, 28% of nurses had bachelor’s degrees.

The authors write about their findings in detail:

These associations imply that patients in hospitals in which 60% of nurses had bachelor’s degrees and nurses cared for an average of six patients would have almost 30% lower mortality than patients in hospitals in which only 30% of nurses had bachelor’s degrees and nurses cared for an average of eight patients.”

Prof. Aiken says the European findings mirror data from the US suggesting “that a safe level of hospital nursing staff might help to reduce surgical mortality, and challenge the widely held view that nurses’ experience is more important than their education.”

The team says their findings back a European Union (EU) decision last year to approve education for nurses within higher education institutions starting after 12 years of general education.

In a linked comment to the study, Alvisa Palese, from the University of Udine in Italy, and Roger Watson, from the University of Hull in the UK, write that this latest research provides support for appropriate patient-to-nurse ratios.

“Whether these findings are used to inform health care policy or how they are implemented in practice will be interesting to see,” they say.

“We fear that the evidence here will not be tried and found wanting, but will rather be deemed too expensive to act upon.”