What is the clinical evidence from this study?

Study design: Cohort. Population: Coronary artery bypass grafting (n=2129). Intervention: Female sex vs. Male sex. Primary outcome: Mortality during the 30 days after coronary artery bypass grafting (p=< 0.05).

September 1, 1996Open Access

Female sex is associated with increased mortality and morbidity early, but not late, after coronary artery bypass grafting

Q: What are the key findings of this study?

Female sex was a significant independent predictor of 30-day mortality after coronary artery bypass grafting (P<0.05), but did not influence late mortality up to 2 years.

Key Result

Female sex was a significant independent predictor of 30-day mortality after coronary artery bypass grafting (P<0.05), but did not influence late mortality up to 2 years.

Study Design

Type

Cohort (n=2,129)

Multicenter

Yes

Structured PICO

Is female sex associated with increased mortality and morbidity in patients undergoing coronary artery bypass grafting compared to male sex?

Population

2,129 consecutive patients (1,727 men [81%], 402 women [19%]) undergoing coronary artery bypass surgery without concomitant procedures in western Sweden between June 1988 and June 1991.

Intervention

Female sex (observational exposure)

Comparator

Male sex

Outcome

Mortality and morbidity during a period of 2 years after coronary artery bypass graftinghard clinical

Female sex is an independent predictor of 30-day mortality and early postoperative complications after CABG, but does not negatively impact late mortality up to 2 years.

Main Result

p-value: p=< 0.05

Abstract

OBJECTIVE: To describe mortality and morbidity during a period of 2 years after coronary artery bypass grafting in relation to gender. DESIGN: Prospective follow-up study. SETTING: Two regional cardiothoracic centres which performed all the coronary artery bypass operations in western Sweden at the time. SUBJECTS: A total of 2129 (1727 (81%) men and 402 (19%) women) consecutive patients undergoing coronary artery bypass surgery between June 1988 and June 1991 without concomitant procedures. RESULTS: Females were older and more frequently had a history of hypertension, diabetes mellitus, congestive heart failure, renal dysfunction and obesity. In a multivariate analysis, taking account of age, history of cardiovascular diseases and renal dysfunction, female sex appeared as a significant independent predictor of mortality during the 30 days after coronary artery bypass grafting (P < 0.05), but not thereafter. Various postoperative complications including neurological deficit, hydro- and pneumo-thorax, perioperative myocardial damage and the need for assist devices and prolonged reperfusion were more common in females than males. CONCLUSION: Females run an increased risk of early death and the development of postoperative complications after coronary artery bypass surgery as compared with males. Late mortality does not appear to be influenced by gender and the long-term benefit of the coronary artery bypass graft operation is similar in men and women.