Evaluation of factors affecting survival of HIV/AIDS patients using Cox and extended Cox models

Abstract

Introduction: Acquired immune deficiency syndrome (AIDS) is a global viral disease that is increasing in populations with high-risk behaviors. Identifying factors prolonging survival of human immunodeficiency virus (HIV)-positive patients is imperative, and retrospective cohort studies with survival analysis approach are most applicable in research. The present study aims to determine an assessment of survival of HIV/AIDS-positive patients and its' related factors. Material and methods: The present retrospective cohort study was conducted based on medical records of HIV-positive patients visiting Behavioral Diseases Counseling Centers in Kermanshah during 1996-2018. Cox and extended Cox regression models were applied for univariate and multivariate analyses. Data were analyzed using STATA-14. Results: The likelihood of one-, five-, and ten-year survival from the time of HIV diagnosis until AIDS stage was found as 0.87, 0.69, and 0.54, respectively, and the likelihood of one-, five-, and tenyear survival until AIDS-related death was estimated as 0.75, 0.44, and 0.21, respectively. The risk of disease progression to AIDS was greater in women and in patients with tuberculosis comorbidity. Receiving antiretroviral therapy reduced the risk of AIDS-related death by 3.9 times. Conclusions: The main correctable factors affecting the survival of HIV/AIDS patients include early diagnosis, adherence to treatment, and receiving periodic services.