Diagnostic Coding May Skew Pneumonia Outcomes Data
(HealthDay News) – The decline in pneumonia-related hospitalizations and associated inpatient deaths seen in 2003–2009 may be a result of diagnostic coding, rather than an actual improvement in outcomes, according to a study published in the April 4 issue of the Journal of the American Medical Association.
Peter K. Lindenauer, MD, of the Baystate Medical Center in Springfield, MA and colleagues analyzed data from the 2003–2009 Nationwide Inpatient Sample. Pneumonia cases were defined either as a primary diagnosis or as a secondary diagnosis with a principal diagnosis of sepsis or respiratory failure.
During the study period, the researchers found that the annual hospitalization rate for patients with a principal diagnosis of pneumonia declined 27.4% from 5.5 to 4 per 1,000. Age- and sex-adjusted mortality decreased from 5.8% to 4.2% (absolute risk reduction [ARR], 1.6%; relative risk reduction [RRR], 28.2%). Over the same period, hospitalization rates for patients with a principal diagnosis of sepsis increased 177.6%, from 0.4 to 1.1 per 1,000, while inpatient mortality decreased from 25.1% to 22.2% (ARR, 3%; RRR, 12%). Hospitalization rates for patients with a principal diagnosis of respiratory failure increased 9.3%, from 0.44 to 0.48 per 1,000, and mortality declined from 25.1% to 19.2% (ARR, 6%; RRR, 23.7%).
"From 2003–2009, hospitalization and inpatient mortality rates for patients with a principal diagnosis of pneumonia decreased substantially, whereas hospitalizations with a principal diagnosis of sepsis or respiratory failure accompanied by a secondary diagnosis of pneumonia increased and mortality declined," the authors write.