Impact of gender on coronary bypass operative mortality.
BACKGROUND
In spite of many reports investigating the influence of gender on coronary artery operations, it is still uncertain whether gender is an independent risk factor for operative mortality. A major problem of previous reports has centered around the fact that men and women constitute quite different populations, thereby making direct comparisons difficult.


METHODS
The Society of Thoracic Surgeons National Cardiac Surgery Database was used to retrospectively examine 344,913 patients undergoing coronary artery bypass graft operations from 1994 through the most recent data harvest. The operative mortality of male and female patients was compared for a variety of single risk factors and combinations of risk factors. A logistic risk model was used to account for all important patient parameters so that individuals could be stratified into comparable categories allowing for direct comparisons of risk-matched male and female patients.


RESULTS
The univariate analysis showed that the 97,153 women carried a significantly higher mortality for each of the risk factors examined. The multivariate analysis and the risk model stratification showed that women had significantly higher mortality as compared to equally matched men in the low- and medium-risk part of the spectrum, but in high-risk patients, there was no difference between male and female mortality.


CONCLUSIONS
Gender is an independent predictor of operative mortality except for patients in very high-risk categories.
Division of Cardiothoracic Surgery, University of Florida Health Science Center, Jacksonville 32209-6511, USA. fhe@mediaone.net
F H
FH
Edwards
J S
JS
Carey
F L
FL
Grover
J W
JW
Bero
R S
RS
Hartz
D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001830:Body Surface Area; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000401:mortality*; D019992:Databases as Topic; D005260:Female; D005544:Forecasting; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis / Q000401:mortality; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D014481:United States / Q000453:epidemiology