Results from a large study carried out in Michigan show 12 percent of hospitalized patients were misdiagnosed with community-acquired pneumonia and given full courses of antibiotics.
Patients at highest risk for misdiagnosis were older, and more likely to have dementia or some other form of altered mental state on admission to hospital.
“While some inappropriate diagnosis of community-acquired pneumonia is unavoidable due to diagnostic uncertainty when patients are first hospitalized, many patients remain inappropriately diagnosed even on hospital discharge,” write the researchers in JAMA Internal Medicine.
“Inappropriate diagnosis of community-acquired pneumonia may harm patients through delayed recognition and treatment of acute (eg, exacerbations of congestive heart failure), chronic (eg, pulmonary cancer), or novel diagnoses (eg, pulmonary cancer) and may lead to unnecessary antibiotic use, adverse effects, and antibiotic resistance.”
Lead author Ashwin Gupta, a physician and researcher at the University of Michigan, and colleagues assessed 17,290 patients admitted to hospital who had a discharge code of pneumonia between July 2017 and March 2020 and received antibiotics during the first couple of days of hospitalization.
The research team found that 12% of patients in the study met the criteria for inappropriate diagnosis of pneumonia, namely, patients with “fewer than two signs or symptoms of pneumonia, or who lacked radiographic findings consistent with pneumonia.”
The group that met the definition of having an inappropriate pneumonia diagnosis were more likely to be older, with an eight percent increased risk for every decade of age, compared with the group who were correctly diagnosed with pneumonia. They were also 79% more likely to have dementia and 75% more likely to have an altered mental state on admission.
In the inappropriately diagnosed group, 88% received a full course of antibiotics and of these 2.1% had antibiotic-related adverse events.
“The high underlying prevalence of community-acquired pneumonia in older populations likely fuels previously discussed cognitive biases,” write Gupta and colleagues. “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 community-acquired pneumonia.
“Highly vulnerable groups are at highest risk of inappropriate diagnosis. These same vulnerable populations are also most likely to be affected by antibiotic-associated adverse events and resulting morbidity. Thus, balancing harms of underdiagnosis and overdiagnosis of community-acquired pneumonia remains essential.”
