Rates of bloodstream infections caused by antibiotic-resistant bacteria are expected to rise substantially across Europe over the next five years, mainly driven by ageing populations, according to new research published on 4 November in the open-access journal PLOS Medicine. Led by Gwenan Knight of the London School of Hygiene and Tropical Medicine, the study highlights how demographic change is likely to intensify the future burden of antimicrobial resistance across the region.
Antimicrobial resistance, commonly known as AMR, is widely recognised as a significant global public health threat. Resistant infections make routine treatments less effective, increase the risk of severe illness and death, and place growing pressure on healthcare systems. To guide prevention strategies and monitor progress towards international targets, it is essential to understand not only current levels of resistance but also how the burden of AMR is likely to change over time as populations evolve.
To address this, the researchers analysed data from more than 12 million routine blood culture susceptibility tests collected in 29 European countries between 2010 and 2019. These data were used to estimate the incidence rates of bloodstream infections caused by different bacteria and to assess patterns of antibiotic resistance. The team then modelled how rates of drug-resistant bloodstream infections might change through to 2050, incorporating projected shifts in population size, age structure, and sex.
The results suggest that bloodstream infection rates will increase overall, although the scale of the rise varies considerably between countries and between different bacteria–antibiotic combinations. A clear demographic pattern emerged. Rates were projected to increase more in men than in women for most of the bacteria studied, and to rise most sharply in older age groups. In particular, adults aged 74 and over are expected to experience the most significant increases, while rates in younger populations are predicted to stabilise or even decline.
The authors note that models which fail to account for age and sex differences are likely to miss a substantial share of the future burden of antimicrobial resistance, especially among older adults and men. Even under scenarios assuming strong public health interventions, the study found that achieving a 10 per cent reduction in resistant infections by 2030—aligned with United Nations targets—would be possible for only around two-thirds of the bacteria–antibiotic combinations examined.
Gwenan Knight emphasised that the future impact of drug-resistant infections will not be evenly distributed. Significant differences are expected across countries, age groups, and sexes. The steepest increases are projected among older adults, particularly those over 65, meaning that simply preventing further rises in resistant bloodstream infections in these groups would already represent a significant public health achievement. Co-author Catrin Moore added that understanding how age and sex shape future AMR trends is a crucial step towards designing targeted interventions that focus on the populations most at risk, helping to reduce illness and deaths associated with drug-resistant infections across Europe.
More information: Naomi R. Waterlow et al, Combining demographic shifts with age-based resistance prevalence to estimate future antimicrobial resistance burden in Europe and implications for targets: A modelling study, PLOS Medicine. DOI: 10.1371/journal.pmed.1004579
Journal information: PLOS Medicine Provided by PLOS
