Design and use of a quantitative scale for measuring presyncope.
BACKGROUND
Vasovagal syncope is common and distressing. One important symptom is presyncope, but there are no clinimetric measures of this. We developed the Calgary Presyncope Form (CPF) and used it to test whether metoprolol reduces presyncope in a randomized trial.


METHODS
The CPF captures the frequency, duration, and severity of presyncope. We administered it to participants in the Prevention of Syncope Trial (POST), a randomized clinical trial that tested the hypothesis that metoprolol reduces syncope and presyncope in adult patients with vasovagal syncope.


RESULTS
The CPF was completed by 44 patients on metoprolol and 39 patients on placebo, of a total of 208 subjects. Completion of the CPF for each of the threedimensions was 84-87% in the 83 respondents. Results were centrally distributed in duration and severity dimensions, but not in frequency. Patients had a median of 1.2 presyncopal spells per day, with a median moderate severity, lasting a median 10 minutes. The 3 scales were statistically independent of each other. These results were independent of subject age, and results in all 3 dimensions were stable over the observation period. There was no significant difference between patients on metoprolol and placebo in any dimension.


CONCLUSIONS
The 3-dimensional CPF is simple, easy to use, stable over time, measures 3 independent variables, and documents that metoprolol does not reduce presyncope.
Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada. sheldon@ucalgary.ca
Robert S
RS
Sheldon
Joseph E
JE
Amuah
Stuart J
SJ
Connolly
Sarah
S
Rose
Carlos A
CA
Morillo
Mario
M
Talajic
Teresa
T
Kus
Fetnat
F
Fouad-Tarazi
Thomas
T
Klingenheben
Andrew D
AD
Krahn
Aaron
A
Sheldon
Mary-Lou
ML
Koshman
Debbie
D
Ritchie
D000328:Adult; D004311:Double-Blind Method; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use; D008875:Middle Aged; D012107:Research Design / Q000592:standards*; D012720:Severity of Illness Index; D013575:Syncope / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology*; D014894:Weights and Measures / Q000592:standards*; D055815:Young Adult
D008790:Metoprolol