Cardiopulmonary bypass has a modest association with cancer progression: a retrospective cohort study

BMC Cancer

Table 3 Cause-specific mortality for isolated open-heart surgery patients with no prior cancer diagnosis, by CPB status

	CABG patients^a(n=43,347)
	Pump^b		Off pump		Kaplan Meier^c			Competing risk model^c
	(n=33,357)		(n=9,990)		Kaplan Meier^c			Competing risk model^c
	n	%^d	n	%^d	HR^e	(95% CI)	p-value	HR^e	(95% CI)	p-value
Cancer-specific mortality
• Unadjusted model	923	2.8%	218	2.2%	1.02	(0.76-1.37)	0.898	1.02	(0.76-1.37)	0.898
• Adjusted model^f					1.13	(0.90-1.42)	0.306	1.16	(0.92-1.46)	0.203
Cardiovascular-specific mortality
• Unadjusted model	2,979	8.9%	754	7.5%	1.01	(0.78-1.31)	0.938	1.01	(0.78-1.31)	0.938
• Adjusted model^f					1.26	(0.89-1.79)	0.186	1.15	(0.86-1.55)	0.344
Other cause-specific mortality
• Unadjusted model	1,862	5.6%	491	4.9%	0.94	(0.73-1.22)	0.658	0.94	(0.73-1.22)	0.658
• Adjusted model^f					1.24	(0.67-2.29)	0.495	1.20	(0.65-2.19)	0.561

^afinal dataset after asymmetric trimming of the propensity score model to improve overlap of the propensity score distributions for patients with and without CPB CABG surgery. The final dataset includes 43,347 patients or 90% of the original dataset.
^bincludes patients with ≥1 on-pump procedure prior to incident cancer.
^cKaplan-Meier estimate treats failures from competing causes as censored observations; competing risk model with regression of exposure on cause-specific hazard.
^d%=number of patients who died / total number in each group*100.
^ehazard ratio for pump/off-pump modeled using Cox proportional hazards model with a robust covariance matrix that accounted for survival times for individuals within a hospital. Zero time for analysis was time of the open-heart surgery.
^fmodel adjusted for age at time of surgery, gender, race, year of surgery, use of blood products, and propensity score.
CABG=coronary artery bypass graft, CPB=cardiopulmonary bypass (or “pump” procedure).

ISSN: 1471-2407