Survival Analysis of CABG Patients by Parametric Estimations In Modifiable Risk Factors - Hypertension and Diabetes

In this paper, modifiable risk factors (hypertension and diabetes) of Coronary Artery Bypass Graft Surgery (CABG) patients are considered. The objective is to analyse survivor’s proportions of CABG patients in the considered risk factors, in complete and incomplete Populations, using suitable survival models. A new approach of complete population from its incomplete population of CABG patients of 12 years observations is used for the survival analysis. In the complete population, censored patients are proportionally included into the known survived and died patients respectively. The availability of a complete population may represent better behaviour of lifetimes / survival proportions for medical research. Survival proportions of the CABG patients of complete and incomplete populations, with respect to the risk factors (hypertension and diabetes) are obtained from suitable, lifetime representing models (Weibull and Exponential). Maximum likelihood method, in-conjunction with Davidon-Fletcher-Powell (DFP) optimization method and Cubic Interpolation method is used in estimation of survivor’s proportions from the parametric models.