ICMR Study Links Carbapenem-Resistant Infections to Higher Mortality and Costs in India

A comprehensive three-year study conducted across 20 tertiary-care hospitals in India has revealed that carbapenem-resistant bacterial infections are significantly driving up patient mortality and healthcare costs. The research, which analyzed data from over 150,000 hospitalized patients between April 2022 and April 2025, provides a stark assessment of the clinical and economic burden posed by antimicrobial resistance (AMR). Published in the October 2026 issue of The Lancet Regional Health – Southeast Asia, the findings underscore the urgent need for integrated surveillance and improved infection control measures within the Indian healthcare system.

Led by the Indian Council of Medical Research (ICMR), the study focused on four major Gram-negative pathogens: Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa. These bacteria are critical targets for surveillance because they have historically been susceptible to carbapenem antibiotics, a class of drugs often reserved as a last-resort treatment for severe infections. The research highlights that when these pathogens develop resistance, the therapeutic options for clinicians diminish rapidly, leading to poorer patient outcomes.

The study found that patients infected with carbapenem-resistant strains faced a substantially higher risk of death compared to those with susceptible infections. The relative risk of mortality was particularly pronounced for E. coli and P. aeruginosa, which showed increases of 41% and 43%, respectively. For K. pneumoniae, the risk was 33% higher, while A. baumannii was associated with a 16% higher relative risk. These figures represent a significant clinical challenge, especially when infections progress to bloodstream involvement.

In cases of bloodstream infections caused by carbapenem-resistant non-fermenting bacteria, such as A. baumannii and P. aeruginosa, mortality rates reached between 46% and 51%. Dr. Kamini Walia, a senior scientist at the ICMR who led the research, emphasized the severity of these findings on social media, noting that the study highlights the necessity of moving beyond simple resistance surveillance toward integrated systems that link AMR data directly to patient outcomes.

Beyond the human toll, the study documented a clear financial penalty associated with drug-resistant infections. Antibiotic treatment costs for resistant cases were found to be 1.1 to 2 times higher than those for susceptible infections. This increase is driven by the need for more expensive, newer-generation antibiotics and the requirement for longer, more intensive hospital care. Patients with carbapenem-resistant E. coli, for instance, experienced an average hospital stay of 23 days, compared to 18 days for those with susceptible infections.

However, the researchers noted a paradox regarding the length of stay for other pathogens. For A. baumannii and P. aeruginosa, the average duration of hospitalization was sometimes shorter in resistant cases, which the authors attribute to early mortality. This suggests that the severity of these resistant infections often leads to poor survival outcomes before a longer hospital stay can even occur, further emphasizing the critical nature of timely diagnosis and effective intervention.

A significant portion of the infections identified in the study were classified as healthcare-associated, meaning they were acquired within the hospital environment rather than the community. The data showed that 85% of E. coli infections, 91.6% of K. pneumoniae, 95.1% of A. baumannii, and 91.9% of P. aeruginosa infections were healthcare-associated. This high concentration of resistant organisms in clinical settings points to the vital importance of rigorous infection prevention and control protocols.

Dr. Sonam Vijay, a researcher involved in the project, stated, "Our findings among 1.5 lakh hospitalized patients, including 16.4% with Gram-negative bacterial infections, highlight the need for timely diagnostics and access to effective, affordable novel antimicrobials to improve outcomes and reduce the economic burden of carbapenem-resistant infections." The study authors advocate for enhanced hand hygiene, environmental cleaning, and the careful management of invasive medical devices to curb the spread of these pathogens.

The researchers cautioned that while the study provides strong evidence of an association between resistance and poor outcomes, it should not be interpreted as a direct indicator of individual hospital performance. The participating institutions are tertiary-care centers that handle the most critically ill patients, and the authors suspect that facilities with less robust laboratory support might face even worse outcomes. The study serves as a call to action for the Indian health system to prioritize antimicrobial stewardship and ensure that patients have access to newer, effective therapies.

As the medical community continues to grapple with the evolutionary contest between bacteria and antibiotics, the ICMR’s work provides a foundational dataset for future policy. By linking microbiological data with clinical reality, the study offers a roadmap for strengthening the national response to AMR, emphasizing that preventing the initial infection is often more cost-effective than attempting to treat a resistant organism after it has taken hold.