The Impact of Age and Gender on Outcomes of Coronary Artery Bypass Grafting

Objective : As the population ages, increasing number of older patients are undergoing adult cardiac surgery. The purpose of the study is to assess the impact of age on postoperative outcomes in patients that undergo coronary artery bypass grafting (CABG).Methods : Patients that are ≥70 years old who underwent CABG were selected from the Nationwide/National Inpatient Sample from 2010 to 2015 using ICD-9-CM diagnosis and procedure codes. The patients who were 70–79 years old were compared to patients aged 80–89 years old to determine if the age difference of the patients had an impact on surgical outcomes. In addition, the gender of the patients 80-89 years old were compared to determine the influence of patient gender on surgical outcomes. The rates of postoperative complications, mortality, hospital length of stay (LOS), and cost were compared using the Chi-square test, multivariable logistic regression analysis, and Wilcoxon rank sum test.Results : A total of 67,568 patients were identified who were ≥70 years old and underwent CABG. Compared to the Septuagenarians, the Octogenarians were more likely to develop cardiac complications (OR [odds ratio] =1.20, 95% CI [confidence interval] 1.12-1.23. They were also more likely to develop renal complications (OR 1.54 95% CI 1.48-1.61, P <0001), respiratory complications (OR 1.2, 95% CI 1.2-2.1, P <0001), and infectious complications (OR=1.41, 95% CI 1.34-1.48, P <0001). The Octogenarians were also more likely to bleed postoperatively (P <0.0001) and have a higher mortality (OR 1.41 95% CI 1.36-1.61, P <0001). Moreover, the older patients had a longer postoperative LOS (median 9 days IQR [interquartile range] 7-13 days compared to the Septuagenarians (median 8 days IQR 6-11 days). The Octogenarians had an associated increased hospital cost (median $39,152 IQR $30, 0003.84 - $53,272.84) compared to the Septuagenarians (median $35,996.16 IQR $27,735.94 - $48,134.38). Furthermore, the female Octogenarians had a higher mortality (OR 1.25 95% CI 1.07–1.46) compared to males in the same age group.Conclusions : Advanced age influences surgical outcomes after CABG. The patients who were ≥80 – 89 years old had worse postoperative outcomes with increased complications and higher mortality compared to the Septuagenarians. Additionally, the Octogenarians who were females had a higher mortality compared to their male counterparts. These findings should help determine treatment options for older patients who need adult cardiac surgery.