THE USE OF COX REGRESSION MODEL IN THE SURVIVAL ANALYSIS FOR LEUKEMIA PATIENTS IN THE REPUBLIC OF YEMEN

Abstract

This study aims at analyzing and studying the theoretical and practical importance of the (Cox) regression model in the analysis of survival as well as measuring the most important factors affecting the survival time for patients with leukemia. Moreover, it aims at reaching the expected survival time for patients and creating a life table for patients by using (Cox) regression model. To achieve these goals, real data were taken for (1168) patients with leukemia in the Republic of Yemen in the period from January 2017 to February 2022. The dependent variable, which is the patient’s condition at the end of the period, was determined in addition to the patient’s survival time and eight independent variables were identified. The effect of these variables on the survival time of patients with leukemia was investigated using the SPSS program. The study concluded several results, the most prominent of them are the following: There are no differences in the incidence rate between males and females and the most age group affected by this disease is (40 years and over). Furthermore, it was found that acute lymphoblastic leukemia (ALL) is the most prevalent type among the other types and there is a difference in the risk of death among those who take intravenous chemotherapy and those patients who take oral chemotherapy. Other significant result was found that there is a higher risk of death for non-regular patients in receiving treatment compared to regular patients in receiving treatment. It was found that the most influencing variables on the survival time of patients are (age, marital status, type of disease, the governorate in which the patient lives, regularity in receiving treatment and type of chemotherapy). Through the life table, it is noticed that the greatest risk in the survival time is in the thirty-sixth month, which is the largest among all other periods, as it reached (0.10). Additionally, the median survival time was reached (35.06) months. Finally, the study found that there are differences in the incidence according to the type of disease in terms of the risk of death as acute lymphoblastic leukemia (ALL) is the most prevalent disease among all diseases and the largest percentage of deaths was among those with chronic myeloid leukemia (CML).