A Cox’s Proportional Model to Assess Survival Prognostic Factors in Patients Over 85 Years of Age Undergoing Heart Surgery

Abstract

Introduction: “The progressive and growing prevalence of octuagenarians (O) and over-octuagenarians (>O), susceptible to cardiac surgery has generated an ethical and economic reflection on the usefulness and opportunity to use the limited resources of intensive care for these patients. Methods: The primary end point of the study has been highlight any difference in post-operative and ICU mortality between patients (O) and (>O) by setting a Cox’s proportional hazard model. Results: The 6.9% of the population studied were 85 years of age or older; therefore the over 85 yrs sub-group (≥ 85 yrs.) was 889 patients and the under 85 yrs sub-group 11966. Hospital mortality was found to be significantly higher (+4.3%) in the over 85 yrs. Factors significantly associated with postoperative hospital survival of over 85 yrs. were found to be: (i) male gender, arterial disease, COPD, pathology of the aortic and mitral valve; (ii) interaction unstable angina and common trunk obstruction, the value of the CCS scale; (iii) RBC and FFP transfusions, together with total blood loss; (iv) post-operative septic shock, acute renal failure, cerebral stroke, mechanical ventilation, ventilator associated pneumonia, and tracheostomy. Conclusions: Our data suggest the importance of the age variable as well as the fact that the two populations are distinct and different. A further and future multivariate analysis will be conducted with the use of propensity score matching.