Medicina

ORIGINAL INVESTIGATION

Causes of Death for Patients
With Community-Acquired Pneumonia
Results From the Pneumonia Patient Outcomes Research Team Cohort Study
Eric M. Mortensen, MD, MSc; Christopher M. Coley, MD; Daniel E. Singer, MD; Thomas J. Marrie, MD;
D. Scott Obrosky, MSc; Wishwa N. Kapoor, MD, MPH; Michael J. Fine, MD, MSc

Background: To our knowledge, no previous study hassystematically examined pneumonia-related and pneumonia-unrelated mortality. This study was performed to
identify the cause(s) of death and to compare the timing
and risk factors associated with pneumonia-related and
pneumonia-unrelated mortality.
Methods: For all deaths within 90 days of presentation, a synopsis of all events preceding death was independently reviewed by 2 members of a 5-memberreview panel (C.M.C., D.E.S., T.J.M., W.N.K., and M.J.F.).
The underlying and immediate causes of death and
whether pneumonia had a major, a minor, or no apparent role in the death were determined using consensus.
Death was defined as pneumonia related if pneumonia
was the underlying or immediate cause of death or played
a major role in the cause of death. Competing-risk Cox
proportionalhazards regression models were used to identify baseline characteristics associated with mortality.
Results: Patients (944 outpatients and 1343 inpatients) with clinical and radiographic evidence of pneumonia were enrolled, and 208 (9%) died by 90 days. The
most frequent immediate causes of death were respiratory failure (38%), cardiac conditions (13%), and infec-

From the Division of GeneralInternal Medicine, Department
of Medicine, and the Center
for Research on Health Care,
University of Pittsburgh
(Drs Mortensen, Kapoor, and
Fine and Mr Obrosky), and the
Center for the Study of Health
Disparities, VA Pittsburgh
Healthcare System (Dr Fine),
Pittsburgh, Pa; the General
Medicine Unit, Department
of Medicine, Massachusetts
General Hospital and Harvard
Medical School, Boston(Drs Coley and Singer);
and the Division of Infectious
Disease, Department of
Medicine, University of Alberta,
Edmonton (Dr Marrie).

P

tious conditions (11%); the most frequent underlying
causes of death were neurological conditions (29%), malignancies (24%), and cardiac conditions (14%). Mortality was pneumonia related in 110 (53%) of the 208
deaths. Pneumonia-related deaths were 7.7times more
likely to occur within 30 days of presentation compared
with pneumonia-unrelated deaths. Factors independently associated with pneumonia-related mortality were
hypothermia, altered mental status, elevated serum urea
nitrogen level, chronic liver disease, leukopenia, and hypoxemia. Factors independently associated with pneumonia-unrelated mortality were dementia, immunosuppression,active cancer, systolic hypotension, male sex,
and multilobar pulmonary infiltrates. Increasing age and
evidence of aspiration were independent predictors of both
types of mortality.
Conclusions: For patients with community-acquired
pneumonia, only half of all deaths are attributable to their
acute illness. Differences in the timing of death and risk
factors for mortality suggest that futurestudies of community-acquired pneumonia should differentiate allcause and pneumonia-related mortality.

Arch Intern Med. 2002;162:1059-1064

NEUMONIA COMBINED with in-

fluenza is the sixth leading
cause of death in the United
States.1 Although the mortality rate from pneumonia
decreased sharply with the introduction
of antibiotic therapy in the 1940s, since
1950, the overall mortalityrate for this illness has either remained stable or increased.2 In a meta-analysis3 of studies of
prognosis, the short-term mortality of patients hospitalized with communityacquired pneumonia ranged from 5.1% for
patients treated in an ambulatory or hospital setting to 36.5% for patients treated
in an intensive care unit.
Prior studies4-6 of pneumonia prognosis focused almost exclusively on...