Study objectives: To study the validity of a recently
developed community-acquired pneumonia (CAP) severity prediction rule
in estimating mortality, to determine its utility in decision making
regarding hospitalization, and to assess factors influencing this
Design: Retrospective chart review.
Setting: Two sites of the University Health Network, the
Toronto General and Toronto Western Hospitals, tertiary-care teaching
institutions with a sizable primary-care and secondary-care source of
referrals, and a total of 900 beds.
Consecutive patients with CAP admitted between February and June
Measurements and results: A single trained
medical records extractor assembled data to compare our population to
that used in developing the CAP prediction rule, in terms of mortality
and to assess reasons for hospitalization. Two hundred fifty-five
eligible patients were admitted, and 244 charts (96%) were available.
Our patients tended to be older, with nearly four times as many
residents of chronic care institutions (39% compared with 10%), and
had a higher risk class distribution than the published cohort. Risk
class-specific mortality was similar in four of five classes. Of the 71
patients in the low-risk classes, 67 had additional reasons for
admission; 18 of which were psychosocial (homelessness, substance
abuse, or inadequate home supports).
CAP severity prediction rule estimates mortality well. Admission of
low-risk patients was linked to psychosocial and other medical reasons
not captured by this rule. The rule can be very useful in assessing the
need for hospitalization; however, there remains a significant
percentage of patients with a low severity score who may require
hospitalization for psychosocial and economic