Invited Commentary: Associations between adverse outcomes for surgical admissions and nurse understaffing – a longitudinal study

In a recent study published in BJS, Meredith¹ and co-authors present their findings of the detrimental effects of nurse understaffing and adverse events for surgical patients. This, as the authors highlight, is a critical yet often overlooked problem that extends far beyond the National Health Service (NHS) in England. Although the paper’s conclusion that ‘understaffing’ is ‘associated with increased risks of a range of adverse events’ may appear obvious, the significance of the findings relies on its universal character – that it is a global problem that requires urgent attention.

The World Health Organization (WHO) has de facto identified a global shortage of healthcare workers, particularly nurses and midwives, who represent more than 50% of the current shortfall. While the shortage of doctors may be manageable, the understaffing of nurses poses a severe threat to health outcomes. In a large observational study, that included nine European countries and data from more than 420 000 patients, published in Lancet in 2014, it was noted that each increase of one patient per nurse was associated with a 7% increase in the likelihood of a surgical patient dying within 30 days of admission².

Two recent reports from the International Council of Nurses (ICN) further emphasise the detrimental effects of nurse understaffing on patient outcomes, and urge readers to view this as a matter of global urgency. In Sustain and Retain in 2022 and Beyond³ the authors project the need to replace up to 13 million nurses globally in the coming years, reflecting alarming rates of nurse attrition driven by stress, burnout, absenteeism, and industrial action. The ICN’s 2023 follow-up report, Recover to Rebuild – Investing in the Nursing Workforce for Health System Effectiveness , calls for a coordinated global effort to establish a sustainable nursing workforce through a long-term, ten-year plan.

The European Confederation of Independent Trade Unions (CESI) also advocates significant investment in the nursing workforce, supporting the establishment of nurse-patient ratios across Europe to improve outcomes, enhance safety, and reduce costs. As the WHO has stated, “Investing in nurses and midwives is good value for money.” (https://www.cesi.org/wp-content/uploads/2019/05/TC-SAN-23-May-2019_position-paper_final_EN.pdf)

It is against this background that we welcome the study performed by Meredith and co-authors, since it reinforces these calls to action by demonstrating the connection between nurse understaffing and increased morbidity rates. Their findings show that understaffing by both registered nurses and nurse assistants  are linked to longer hospital stays, a higher incidence of hospital-acquired conditions such as deep vein thrombosis, pneumonia, and pressure ulcers, as well as an increased risk of mortality. Notably, the effects of registered nurses’ understaffing on adverse outcomes, including a 9.2% increase in mortality, were more pronounced than those of nurse assistants. The consequences of inadequate staffing are both predictable and preventable, and the costs of inaction—both in terms of patient outcomes and financial burden—will far exceed the investment needed to address this issue.

Although the study effectively highlights this critical issue, a few methodological aspects could have been refined. The hazard ratios, though statistically significant, are modest given the large cohort size (>213 000 hospital admissions). In addition, translating relative risks into absolute measures, such as the number needed to treat (NNT) or harm (NNH), would have provided more practical insights for healthcare providers and policymakers. For instance, an increased relative risk of 9.2% in mortality would be clearer if expressed in absolute terms. Likewise, the study’s robustness would have benefited from more detailed data and consideration of key variables such as comorbidities and prophylactic measures. 

Acknowledging these shortcomings is important, but they do not detract from the broader message that nurse understaffing has serious and far-reaching consequences. This study adds to the growing body of evidence that supports the urgent need for healthcare systems worldwide to prioritize adequate staffing. The international community must heed this call to action. We have to stop viewing nursing as a soft target where quick savings can be made, and instead recognise that the long-term effectiveness of health systems depends on the sustainability of the nursing workforce.

In conclusion, while Meredith et al.’s study may emphasize an issue that appears self-evident, its contribution lies in reasserting the importance of addressing a problem that remains inadequately tackled. Although further research and more detailed data are necessary, the immediate focus should be on recognising and responding to the clear link between nurse understaffing and adverse patient outcomes. Strengthening the nursing workforce is not only essential for enhancing health system effectiveness but also for ensuring better patient care.