Predicting survival of heart failure patients using the cox proportional hazards model

Abstract

The main purpose of this study was to predict the survival of heart failure patients using the Cox Proportional Hazards Model. Specifically, the study aimed to find out whether health problems such as diabetes, hypertension, anaemia as well as heart disease preconditions such as serum creatinine, ejection fraction, serum sodium, and creatinine phosphokinase, predict the survival of heart failure patients. This study relied upon purely secondary data obtained from the Mbarara Heart Failure Registry (MAHFER) and from the Department of Internal Medicine, Mbarara University of Science and Technology, Mbarara, Uganda. The data consisted of 299 patients, of whom 105 were women and 194 were men aged between 40 and 95 years old. With the support of the RStudio statistical programme, the Cox Proportional Hazards Model was estimated to determine the survival of heart failure patients. According to the model, each additional year of patient age increases the hazard (HR = 1.0446; p-value = 8.41e-07). As a result, survival decreases as the age of the heart patient increases. Most importantly, heart failure patients with hypertension (high blood pressure) had a worse survival than patients without hypertension (HR = 1.5948; p-value = 0.0284). Furthermore, when all other factors were held constant, increased ejection fraction was found to decrease the hazard (HR = 0.9495; p-value = 2.57 e-07) and improve survival, whereas increased creatinine was found to increase the hazard (HR = 1.4167; p-value = 1.05 e-07), hence reducing survival. According to the study findings, there is an urgent need to consider issues such as high blood pressure as well as heart conditions such as high serum creatinine and a low ejection fraction in order to improve the survival of heart failure patients. Furthermore, as a heart failure patient ages, so does his or her demand for health care to extend their survival.