Bloodstream Infections Increase When Older Adults Aren't Given Antibiotics for UTIs

The push to limit the use of antibiotics in the treatment of urinary tract infections (UTIs) could be leading to an increase in bloodstream infections in elderly patients.

New research published last month in The BMJ offers new data points that could fuel additional discussion about how to tailor antibiotic stewardship programs so they sufficiently curtail antibiotic resistance while also limiting adverse effects associated with the reduction of the use of the drugs.

A team of British investigators wanted to gain a better handle on potential negative impacts of delaying or avoiding antibiotic use in elderly patients who see a primary care physician for the treatment of UTIs. The team leveraged a database of patient records stretching from 2007-2015 and encompassing more than 157,000 patients over the age of 65 who sought care for more than 312,000 urinary tract infections.

Paul Aylin, MBChB, a professor of epidemiology and public health at Imperial College London, and colleagues wrote that UTIs are the second most common diagnosis for which empirical antibiotic prescriptions are written, but more than half of the antibiotic prescriptions for older adults suspected of having UTIs are believed to be unnecessary.

Paul Aylin, MBChB

Aylin noted that national guidelines in the United Kingdom and elsewhere have called for a reduction in the use of antibiotics to treat UTIs in primary care settings, and data suggest those guidelines have succeeded in reducing the use of antibiotics.

“Antibiotic resistance is a major threat to public health that is being driven by the overuse of antibiotics,” Aylin told Contagion® . “Current UK recommendations suggest healthcare professionals take a number of different factors into account when deciding whether to prescribe antibiotics immediately or consider a back-up antibiotic prescription for patients with a suspected UTI infection.”

Aylin and colleagues found 7.2% of the patients in the study cohort were not given a prescription for antibiotics, and 6.2% of patients were prescribed antibiotics only after a delay.

However, the data also showed that bloodstream infections were more likely in patients who were not immediately given antibiotics. Although the overall rate of bloodstream infection within 60 days of initial UTI was just 0.5%, the rate of bloodstream infections among patients not given an antibiotic was 2.9%. Moreover, the rate of bloodstream infections for patients who were not initially given an antibiotic but who returned to the clinic within a week and received a prescription was 2.2%. Among patients given an antibiotic at their initial consultation, the rate of bloodstream infection was just 0.2%.

The data also show a link between antibiotic prescriptions and mortality. Patients who were not given antibiotics were found to be twice as likely to die as those given an immediate prescription. Patients who were given antibiotics after a delay were 1.16 times as likely to die compared to the immediate antibiotic group.

One reason for the high mortality rate was sepsis. The risk of sepsis in patients with UTI increases with age, and the study notes that the mortality rate among patients with severe sepsis is 20-40%.

Indeed, a second study published simultaneously in The BMJ showed that delaying antibiotics in elderly patients with UTI could lead to a higher risk of sepsis and death, particularly in men over the age of 85.

Aylin said physicians treating patients with UTIs should follow national guidelines, including the parts of those guidelines that suggest antibiotics might sometimes be warranted.

“This study highlights the importance of taking age into account when making clinical decisions about antibiotic prescribing in order to reduce the risk of complications,” Aylin said.