Community acquired pneumonia is often inappropriately diagnosed in hospital admissions, particularly among older adults with dementia, and can lead to in-hospital antibiotic-associated adverse events, such as Clostridioides difficile.
Diagnoses of community acquired pneumonia (CAP) in hospital admissions were often incorrect, particularly in elderly patients with dementia or altered mental status, in a recent cohort study conducted across 48 hospitals.
While acknowledging that some inappropriate diagnosis of CAP is unavoidable due to diagnostic uncertainty at time of admission, Ashwin Gupta, MD, Medicine Service, Veterans' Affairs, Ann Arbor Healthcare System, Ann Arbor, MI, and colleagues found that the diagnosis often remains through discharge despite patients not meeting diagnostic criteria.
"Inappropriate diagnosis of CAP may harm patients through delayed recognition and treatment of acute...,chronic...,or novel diagnoses..., and may lead to unnecessary antibiotic use, adverse effects and antibiotic resistance," they warn.
To ascertain the incidence, and factors related to inappropriately diagnosing CAP in hospital admissions, the investigators applied a National Quality Forum (NQF)-endorsed and validated metric of inappropriate CAP diagnosis. The metric defined inappropriate diagnosis as any antibiotic treatment of CAP in a patient with fewer than 2 signs or symptoms of pneumonia, or who lacked radiographic findings consistent with pneumonia.
In the period between July 2017 and March 2020, 17,290 adult patients treated for pneumonia at 48 Michigan hospitals were included in the study. Patients were eligible if admitted to general care with a discharge diagnostic code of pneumonia, and who received antibiotics on day 1 or 2 of hospitalization. Patients were excluded if treated for an additional infection unrelated to pneumonia, were severely immunocompromised, were pregnant, were admitted for comfort measures, or who left against medical advice.
The study highlights significant diagnostic challenges in identifying CAP, particularly in elderly patients with cognitive impairments such as dementia or altered mental status.
Approximately 12% of the studied cohort received an inappropriate diagnosis of CAP, with significant variation among hospitals.
Despite guidelines recommending reconsideration and cessation of antibiotics within 48 to 72 hours if infection is ruled out, few cases saw antibiotic cessation.
In addition to reviewing medical records from 90 days preceding hospitalization through 30 days after discharge, patients were phoned 30 days post-discharge for additional outcome data. Adverse event outcomes included 30-day mortality, readmission, emergency department visit, Clostridioides difficile infection, and/or in-hospital antibiotic-associated adverse events documented by a physician.
Gupta and colleagues reported that 12% of the cohort (2,079) met criteria for inappropriate diagnosis.The incidence varied between hospitals, with 30 of the 48 hospitals having inappropriately diagnosed CAP in 10% or more. In the patients meeting criteria for having an inappropriate diagnosis, radiographic criteria was not present in 73.6%, 24.4% had fewer than 2 signs or symptoms of pneumonia, and 2.0% met neither criterion. Dyspnea and/or cough were the most common presenting symptoms in both those with CAP, and those receiving an inappropriate CAP diagnosis.
On multivariate analysis, compared with patients with CAP those inappropriately diagnosed were older (adjusted odds ratio [AOR] 1.8, 95% confidence interval [CI] 1.05-1.11) and more likely to have dementia (AOR 1.79, 1.55-2.08) or present with altered mental status without dementia (AOR 1.75, 1.39-2.19).
"The high underlying prevalence of CAP in older populations likely fuels...cognitive biases," Gupta and colleagues suggest. "Additionally, patients with cognitive impairment may have difficulty communicating.As a result, physicians may anchor on nonspecific data—eg, white blood cell count, fever in isolation—to make the diagnosis of CAP."
The investigators point out that although guidelines for starting empiric antibiotic treatment typically recommend reconsideration, de-escalation, and cessation within 48 to 72 hours once infection has been ruled out, they found few cases of antibiotic cessation.
"Rather, patients empirically receiving antibiotic therapy for presumed CAP typically received a full antibiotic course," Gupta and colleagues reported.They also noted that the full courses of antibiotic treatment, compared to brief courses, were associated with antibiotic-related adverse events.
Reference
1, Gupta AB, Flanders SA, Petty LA, et al. Inappropriate diagnosis of pneumonia among hospitalized adults. JAMA Intern Med. Published online March 25, 2024. doi:10.1001/jamainternmed.2024.0077.Accessed April 1, 2024.
