Antibiotics for Most Lower Tract Respiratory Infections Are Not Efficacious

For patients with a deep cough and a belief they have a more serious illness, they may be prompted to see their providers and look to get prescribed medicine as they think a stronger therapy will see a resolution of symptoms sooner than if the cough and infection are left to resolve on their own. And in a large prospective study, investigators reported that of the 29% of people given an antibiotic during their initial medical visit who were experiencing lower tract respiratory infections (LTRI), there was no effect on the duration or overall severity of cough compared to those who didn’t receive an antibiotic.¹

“Provision of an antibiotic had no effect on the duration or overall severity of cough, including in patients with viral, bacterial, and mixed infections,” the investigators wrote in their study that appeared in the Journal of General Internal Medicine.¹

“This isn't really new news, but patients and sometimes physicians still don't totally get this,” Dan Merenstein, MD, professor of family medicine at Georgetown University School of Medicine and lead author of the study said in an interview with Contagion. “In this large prospective study, antibiotics had no measurable impact on the severity or duration of cough due to acute LRTI.”

Merenstein points out that upper respiratory tract infections usually include the common cold, sore throat, sinus infections, and ear infections and have well established ways to determine if antibiotics should be prescribed; however, for LRTI, he says they have the potential to develop into a more severe infection and that about 3% to 5% of these patients have pneumonia. And without easy access to X-rays to rule out that respiratory illness, antibiotics without evidence of bacterial infection still may be prescribed, Merenstein surmises.²

He also points out that patients see their providers to seek out medicine for resolution of symptoms like a deep cough. “Patients don't necessarily want antibiotics, they want to get better,” Merenstein said.

What the Data Showed
The objective of this study was to evaluate the impact of antibiotic use on the duration and severity of acute LRTI. Of the 718 patients with baseline data, 29% had an antibiotic prescribed. The antibiotics prescribed in this study for LRTI were all prescribed appropriate antibiotics to treat bacterial infections, the investigators reported. The most common antimicrobials included amoxicillin-clavulanate, azithromycin, doxycycline, and amoxicillin in 85% of patients.¹

To determine if there was an actual bacterial or viral infection present, beyond the self-reported symptoms of a cough, the investigators confirmed the presence of pathogens with advanced lab tests to look for microbiologic results classified as only bacteria, only viruses, both virus and bacteria, or no organism detected. For those with a confirmed bacterial infection, the length of time until illness resolution was the same for those receiving an antibiotic versus those not receiving one, approximately 17 days.²

Ancillary Findings and Conclusions
“Receipt of an antibiotic did reduce the likelihood of a follow-up visit (14.1% vs 8.2%, aOR 0.47, 95% CI 0.26-0.84), perhaps by removing the motivation of getting an antibiotic at a follow-up visit,” the investigators pointed out.¹

They also concluded there needs to be better alignment of expectations of resolving LRTI with antibiotics, especially in the absence of any definitive proof of bacterial infection. “Patients had unrealistic expectations regarding the duration of LRTI and the effect of antibiotics which should be the target of antibiotic stewardship efforts,” the investigators wrote.¹

Merenstein makes a further distinction between pediatric and adult patient encounters. “So often now parents come in and just want what is best for [their children], ie not always antibiotics,” Merenstein said. “But for adults we seem to be lagging. The good news is we can change, and hopefully we won’t continue to have unrealistic expectations for cough.” 


Reference

1.Merenstein DJ, Barrett B, Ebell MH. Antibiotics Not Associated with Shorter Duration or Reduced Severity of Acute Lower Respiratory Tract Infection. J Gen Intern Med. Published online April 15, 2024. doi:10.1007/s11606-024-08758-y

2.Antibiotics Aren’t Effective for Most Lower Tract Respiratory Infections. Georgetown University Medical Center press release. April 11, 2024. Accessed April 16, 2024.
https://www.newswise.com/articles/antibiotics-aren-t-effective-for-most-lower-tract-respiratory-infections