Antibiotic Selection but not Treatment Duration Follows Guidelines for Community Acquired Pneumonia

Adherence to in-patient treatment guidelines for community-acquired pneumonia (CAP) was higher for antibiotic choice than for duration of treatment, in a study in Norway that found elevated C-reactive protein (CRP) was one factor associated with longer treatment durations.¹

"This finding suggests that clinicians may prioritize laboratory results, such as CRP levels, over the patient's clinical condition when determining the duration of antibiotic therapy," remarked lead author Dagfinn Markussen, PhD Candidate, University of Bergen, Bergen, Norway, and colleagues.

"This emphasis on inflammatory markers could lead to prolonged antibiotic use, even when the patient's clinical status may not warrant it," the investigators cautioned.

Markussen and colleagues sought to identify patient factors that might contribute to physicians adhering to or varying from treatment guidelines for inpatients admitted with diagnosis of CAP. The study consisted of two cohorts with identical inclusion and exclusion criteria drawn from a randomized controlled trial (that had investigated rapid syndromic testing) and additional, prospectively identified patients.

"This approach allowed for a more robust analysis by including a larger patient population, facilitating a comprehensive evaluation of guideline adherence over time," Markussen told Contagion.

A total of 479 patients were included in the analysis of empirical antibiotic treatment, and 341 in the treatment duration analysis. Among the exclusion criteria was clinical instability at day 5 or 7 of antibiotic treatment; with stability defined as afebrile, respiratory rate of ≤24/minute, peripheral oxygen saturation >90% on ambient air, and ability to eat.

Norwegian guidelines for inpatient treatment of CAP recommend total antibiotic duration of 5 days for clinically stable patients with mild to moderate symptoms, corresponding to CRB-65 score of 0-2; and 7 days for more severe symptoms.

Markussen and colleagues reported that antibiotic selection largely conformed to guideline recommendation, with 80 % of antibiotics consistent with guidelines. Factors associated with variance from the recommended antibiotic were antibiotic allergy, prior antibiotic treatment within the month before admission, and a high CRB-65 score.

Treatment duration, however, exceeded guideline recommendation in 79.8% of the cohort included in analysis.The median antibiotic duration for all patients in the analysis was 7.9 days, with 19.6% exceeding 10 days.For those with a CRB-65 score of ≤2, where guidelines recommend 5 days, the median was 7.8 days.The median duration of in-hospital antibiotic treatment was 2.9 days, and 5 days in post-discharge treatment.

"We ...want to stress the importance of optimizing discharge practices within stewardship programs, as post-discharge prescriptions account for a large proportion of the total treatment duration," the investigators indicated.

The principle factors associated with treatment durations exceeding recommendation included an elevated CRP level, and length of stay exceeding 2 days.The detection of Gram-negative bacteria was also associated with longer treatment durations.

"The prolonged treatment in these cases (of Gram-negative bacteria) may be warranted, as the empirical regimens might not adequately cover these bacteria," the investigators acknowledged."However, it is important to note that the presence of bacteria, especially when detected from non-sterile body sites such as the airway, does not always indicate an active infection.

Markussen pointed out that their findings are not necessarily able to be generalized to other settings."Norway's success in maintaining low antibiotic use and resistance is largely attributed to comprehensive stewardship strategies implemented at both national and institutional levels.Healthcare institutions receive regular feedback on antibiotic prescriptions, including broad-spectrum antibiotic usage, with national averages serving as benchmarks."

"Previous studies, including ours, have shown that the success of these interventions is highly dependent on their implementation and context," Markussen said. "Engaging stakeholders is essential for designing and executing effective stewardship interventions."

Reference

1. Markussen DL, Wathne JS, Ritz C, et al. Determinants of non-adherence to antibiotic treatment guidelines in ospitalized adults with suspected ocmmunity-acquired pneumonia: A prospective study. Antimicrob Resist Infect Control 2024 Nov 23; 13:140. doi:10.1186/s13756-024-01494-2. Accessed December 2, 2024.