Pneumonia patients prescribed more antibiotics, causing adverse events

USA: Two-thirds of patients hospitalized with pneumonia receive more antibiotics than they probably need, finds a recent retrospective study.

According to the study, published in the journal Annals of Internal Medicine, more than 90% of the excess antibiotics were prescribed at discharge. Excess antibiotic treatment was linked to an increased risk of adverse events.

"Society is still facing a crisis of antibiotic resistance, mainly caused by unabated antibiotic overuse. This occurs due to natural selection: prescribing more antibiotics causes more selective pressure driving greater resistance. Thus, to decrease resistance, fewer antibiotics should be prescribed," Brad Spellberg and Louis B. Rice write in an accompanying editorial.

Exceeding the shortest effective duration of antibiotic treatment is of no benefit, as shown by some randomized trials. Valerie M. Vaughn, University of Michigan Medical School and VA Ann Arbor Health System, Ann Arbor, Michigan, and colleagues conducted the study to examine predictors and outcomes associated with excess duration of antibiotic treatment in patients hospitalized with pneumonia.

For the purpose, the researchers studied 6481 general care medical patients with pneumonia in Michigan hospitals between 2017 and 2018. Some 68% received antibiotics for longer than the shortest effective course based on guidelines. The median excess duration was 2 days (2526 excess days per 1000 patients).

The primary outcome was the rate of excess antibiotic treatment duration (excess days per 30-day period).

Key findings of the study include:

• Antibiotics prescribed at discharge accounted for 93.2% of excess duration.


• Patients who had respiratory cultures or nonculture diagnostic testing, had a longer stay, received a high-risk antibiotic in the prior 90 days, had community-acquired pneumonia, or did not have a total antibiotic treatment duration documented at discharge were more likely to receive excess treatment.


• Excess treatment was not associated with lower rates of any adverse outcomes, including death, readmission, emergency department visit, or Clostridioides difficile infection.


• Each excess day of treatment was associated with a 5% increase in the odds of antibiotic-associated adverse events reported by patients after discharge.

"The study adds to growing literature that short-course therapy in pneumonia is safe and that longer durations are not just unnecessary but potentially harmful," write the authors.

"Future interventions should focus on whether reducing excess treatment and improving documentation at discharge improves outcomes," they concluded.

To read the complete study log on to DOI: 10.7326/M18-3640