Self-reported functional status as a predictor of coronary artery bypass graft surgery outcome in elderly patients

Surgeons have traditionally relied mainly on clinical intuition in the selection of elderly candidates for coronary artery bypass grafting (CABG). The overall increasing number of patients undergoing CABG and limited resources require that a more rational approach be used to screen out candidates who are least likely to benefit from the surgery.

Preoperative functional status is a more sensitive predictor of mortality and poor postoperative functional status than age.

Retrospective preoperative and postoperative geriatric assessment was obtained for 123 patients who had undergone CABG at the Montreal General Hospital. Montreal, Quebec. Preoperative and postoperative health and functional status were assessed using the Canadian version of the Medical Outcomes Study 36-Item Short-Form (SF-36) 1 to 1.5 years following surgery. The questionnaires were compiled according to the method described by Stewart et al and scores were transformed linearly to a 0 to 100 scale. In addition to functional status, the presence of comorbidities and other risk factors known to influence the outcome of CABG were recorded.

There was no significant difference in the likelihood of having a poor functional status before or after surgery, or death as an outcome of CABG in the young elderly group versus the old elderly group. Preoperative functional status was found to predict postoperative functional status; however, there was no significant association between preoperative functional status and the presence of comorbidity. The presence of comorbidity did not affect the postoperative functional status, but increased the likelihood of death.

Functional status was demonstrated to be a significant predictor of CABG outcome. When compared with age, functional status was also found to be a more reliable predictor of CABG outcome, which had not been previously demonstrated. Women were found to be more likely to have a poor preoperative functional status than their male counterparts. This may account in part for the decreased success rate of CABG in elderly women.