Prevalence, Risk of Mortality of Antimicrobial Resistance - A Global Review

• In ICU
• Tue, 26 Aug 2025

Antimicrobial resistance (AMR) is a major global health threat, with rising prevalence worsened by the COVID-19 pandemic. Hospitals are particularly high-risk environments for AMR due to heavy antibiotic use and vulnerable patient populations. Contributing factors include increased virulence, reduced antibiotic effectiveness, improper dosing, and ageing populations. While AMR has been linked to millions of deaths, current estimates are largely based on community settings, leaving uncertainty about its direct impact in hospitals. 

A recent study aimed to synthesise global hospital-based data to determine the prevalence of AMR and its direct effect on mortality compared to non-AMR infections, thereby informing public health priorities.

Researchers used studies reporting on the prevalence of AMR in hospital-acquired infections and associated mortality. The review included 34 studies (20,658 patients) from 18 countries, primarily in North America, Asia, and Europe, with no studies from Africa, the Middle East, Russia, or India. Most studies were observational. 

AMR prevalence in hospitalised patients was high (36.5%) and significantly associated with increased mortality. Sensitivity analyses highlighted higher risks for in-hospital deaths and AMR-related bacteraemia. While study quality was generally high, evidence of publication bias was found, and the overall certainty of mortality evidence was rated low.

The review and meta-analysis confirms that AMR is a critical global health threat, significantly associated with increased in-hospital mortality and a high prevalence (around 37%) among hospitalised patients. The adjusted risk of death was 1.58 times higher in patients with AMR infections compared to those with non-resistant infections, especially in cases of bacteraemia and when death occurred during the same admission.

The study also highlights major data gaps, especially in high-burden regions like sub-Saharan Africa, India, the Middle East, and Russia, where hospital-based AMR mortality data are lacking despite widespread resistance. Factors like empirical antibiotic use, poor diagnostics, and high rates of co-infections (e.g., HIV, TB) may contribute to this gap. 

AMR was shown to directly worsen patient outcomes even after adjusting for age and disease severity, underscoring its clinical relevance beyond just being a public health concern. However, few studies identified whether resistance was acquired in hospitals or the community, and mechanistic modelling linking AMR transmission to mortality was rare.

These findings emphasise the urgent need for better surveillance, standardised study designs, more prospective research, rapid diagnostics, and strengthened antibiotic stewardship, especially in underrepresented regions, to reduce the global impact of AMR and help meet international health goals.

Source: The Lancet
Image Credit: iStock 
 

References:

George NA, Pan D, Silva L et al. (2025) The prevalence and risk of mortality associated with antimicrobial resistance within nosocomial settings—a global systematic review and meta-analysis of over 20,000 patients.The Lancet.