The vast majority of research in the area of community-acquired pneumonia (CAP) has been based on patients admitted to the hospital, yet the majority of patients with CAP are treated on an ambulatory basis as outpatients, either by primary care physicians or in emergency departments. Few studies have been conducted in outpatients with pneumonia, and there is a paucity of data on short- and long-term morbidity or mortality and associated clinical correlates in this group of patients.
In a study by Eurich, et al. (2012), all CAP patients presenting to seven emergency departments in Edmonton, Alberta, Canada from 2000 to 2002 were prospectively enrolled in a population-based registry. Clinical data, including pneumonia severity index (PSI) were collected at time of presentation. Patients discharged to the community were then followed for up to five years through linkage to the provincial administrative databases. The current report provides the rationale and design for the cohort, as well as describes baseline characteristics and 30-day morbidity and mortality.
The total sample included 3,874 patients. After excluding patients who were hospitalized, died or returned to the emergency department the same day they were initially discharged (n = 451; 12 %), and patients who could not be linked to provincial administrative databases (n = 237; 6 %), the final cohort included 3186 patients treated according to a validated clinical management pathway and discharged back to the community. Mean age was 51 (SD = 20) years, 53 percent male; 4 percent resided in a nursing home, 95 percent were independently mobile, and 88 percent had mild (PSI class I-III) pneumonia. Within 30 days, return to emergency department was common (25 percent) as was hospitalization (8 percent) and 1 percent of patients had died.
The researchers say their study will add to the understanding of the determinants and outcomes in this under-researched patient population. They add that the rich clinical data along with the long-term healthcare utilization and mortality will allow for the identification of novel prognostic indicators. Given how under studied this population is, the researchers say the findings should aid clinicians in the routine care of their outpatients with pneumonia and help define the next generation of research questions. Their work was published in BMC Infectious Diseases.
Reference: Eurich DT, Majumdar SR and Marriet TJ. Population-based cohort study of outpatients with pneumonia: rationale, design and baseline characteristics. BMC Infectious Diseases 2012, 12:135 doi:10.1186/1471-2334-12-135