Derivation and validation of a clinical system for predicting pneumonia in acute stroke.
OBJECTIVE
We derived and validated a clinical prediction rule that can be used to predict post-stroke pneumonia.


METHODS
We conducted a retrospective cohort study of patients admitted to hospital with a stroke. The cohort was subdivided into a derivation group and a validation group. Within the derivation group, a point scoring system was developed to predict pneumonia based on a logistic regression model. The point scoring system was then tested within the validation group.


RESULTS
Of the 1,363 patients with stroke, 10.5% of patients experienced new pneumonia. The most points were assigned for abnormal swallowing result and history of pneumonia (4 points), followed by greater NIHSS score (3 points), patient being 'found down' at symptom onset (3 points), and age >70 years (2 points). A 3-level classification system was created denoting low, medium and high risks of pneumonia, which accurately predicted pneumonia in the validation group. The discriminatory accuracy of the 3-level clinical prediction rule exceeded the acceptable range in both the derivation group (c statistic: 0.78) and validation group (c statistic: 0.76).


CONCLUSIONS
A simple scoring system was derived and validated. This clinical scoring system may better identify stroke patients who are at high risk of developing new pneumonia.
Chumbler
Neale R
NR
VA HSR&D Center of Excellence on Implementing Evidence-Based Practice, Richard L. Roudebush VAMC, Indianapolis, IN 46202, USA. neale.chumbler@va.gov
Williams
Linda S
LS
Wells
Carolyn K
CK
Lo
Albert C
AC
Nadeau
Steven
S
Peixoto
Aldo J
AJ
Gorman
Mark
M
Boice
John L
JL
Concato
John
J
Bravata
Dawn M
DM
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000150:complications* / Q000503:physiopathology; D016009:Chi-Square Distribution; D015331:Cohort Studies; D003661:Decision Support Techniques; D003680:Deglutition Disorders / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D018579:Patient Selection; D011014:Pneumonia / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D020521:Stroke / Q000150:complications* / Q000503:physiopathology