Demographic shifts could boost drug-resistant infections across Europe

The rates of bloodstream infections caused by drug-resistant bacteria will increase substantially across Europe in the next five years, driven largely by aging populations, according to a new paper published in PLOS Medicine by Gwenan Knight of the London School of Hygiene and Tropical Medicine, UK, and colleagues.

Antimicrobial resistance (AMR) is a global public health crisis. To effectively target interventions and track progress toward international goals, accurately estimating how the AMR burden will change over time is necessary.

In the new study, researchers analyzed data from more than 12 million routine blood tests for bacterial infection susceptibility in 29 European countries between 2010 and 2019.

They used these data to generate incidence rates of these infections and predict how rates of drug-resistant bloodstream infections may change through 2050, accounting for projected population changes.

The researchers found that bloodstream infection rates are predicted to increase, with varying burdens by country and by bacteria-antibiotic combination. Rates are expected to rise more in men than women across six of the eight bacteria studied, and are projected to increase more dramatically in older age groups (74+ years) while stabilizing or declining in younger populations.

Models that don’t account for age and sex may miss a large part of the future burden, especially among men and older adults, the authors note. Even with strong public health interventions, achieving a 10% reduction in resistant infections by 2030 (aligned with UN targets) was only possible for about two-thirds of bacteria-antibiotic combinations, the study concluded.

Knight adds, “Our study shows that the future burden of drug-resistant infections won’t be uniform—there will be substantial differences between countries, as well as across age groups and between sexes. We see the steepest increases in incidence projected in older age groups, particularly the over 65s, meaning that simply preventing further rises in resistant bloodstream infections would already be a major public health achievement.”

“What I found most interesting was bringing together different strands of data to show the bigger picture. Age and sex are still rarely considered in antimicrobial resistance projections, yet they make a real difference to who is most affected. Combining these factors with demographic and infection trends really highlighted how challenging it will be to reverse the steady rise in bloodstream infections across Europe.”

Co-author Catrin Moore states, “This is a fantastic step forward in understanding the way that age and sex will influence the burden of drug-resistant infections in different European countries in the coming years. This will help us design intervention studies focusing on the populations most at risk in the future to reduce the mortality and morbidity associated with drug-resistant infections.”