Socioeconomic status and comorbidity as predictors of preoperative quality of life in cardiac surgery

Objective: Preoperative quality of life of patients undergoing cardiac surgical procedures has been associated with postoperative morbidity, survival, and quality of life. Patients of lower socioeconomic status have disproportionately greater cardiovascular disease burden and more complications of cardiovascular disease. We examined the interactive effects of demographic characteristics, socioeconomic status, and comorbidity on preoperative functional quality of life measured by the well-validated cardiovascular disease-specific Duke Activity Status Index. Methods: The patient population consisted of 5581 patients between May 1995 and January 1999 who underwent operations on cardiopulmonary bypass: isolated coronary artery bypass grafting, isolated valve procedures, or combined coronary artery bypass grafting and valve procedures and had a preoperative Duke Activity Status Index, along with socioeconomic status information from United States 2000 census data. Predictors were identified by logistic regression for maximum value of baseline DASI and linear regression for DASI scores less than maximum by means of bagging variable selection. Results: Lower socioeconomic status was associated of lower risk-adjusted quality of life (maximum Duke Activity Status Index P = .0002, less than maximum Duke Activity Status Index P = .0007). Older age, female sex, certain comorbidities, higher New York Heart Association class, lower left ventricular function, and reoperation were also statistically significantly associated with lower preoperative Duke Activity Status Index. Conclusion: Lower socioeconomic status is associated with lower risk-adjusted quality of life for patients undergoing cardiac surgery. Quality of life affects morbid outcomes, so further characterization of risk factors for poor quality of life offers an opportunity for intervention.