Evaluation of Laboratory Values Affecting Mortality of End-stage Renal Disease Patients: A Competing Risks Approach

Abstract

Abstract Background Chronic Kidney Disease (CKD) is a prevalent and life-threatening situation recognized as an emerging health issue. The present study aimed to evaluate the effect of laboratory parameters on the survival of patients with End-Stage Renal Disease (ESRD) in a hemodialysis (HD) center in Iran. Materials and methods This study was conducted on patients receiving chronic HD in Iran Helal Pharmaceutical and Clinical Complex between 2014–2018. The survival time was considered as the time interval between HD initiation and death. Receiving kidney transplantation was regarded as a competing risk, and an improper form of two-parameter Weibull distribution was utilized to simultaneously model the time to both death and renal transplantation. The Bayesian approach was conducted for parameters estimation. Results Overall, 29 (26.6%) patients expired, and 19 (17.4%) received kidney transplants. The male gender was related to poor survival, having nearly 4.6 folds higher hazard of mortality (90% HPD region: 1.36–15.49). Moreover, Serum calcium levels ≥9.5 mg/dL (adjusted Sub-hazard ratio (S-HR)=2.33, 90% HPD region: 1.05–5.32) and intact parathyroid hormone (iPTH) ≤150 pg/mL (adjusted S-HR = 2.56, 90% HPD region: 1.09–6.15) were associated with an elevated hazard of mortality. The cumulative incidence function (CIF) for transplantation was greater than death in the first two years of the study. Subsequently, the CIF for death exceeded transplantation in the following two years. The 4-year cumulative incidence of death and kidney transplantation was 63.7% and 36.3%, respectively. Conclusion Male gender, hypercalcemia, and hypoparathyroidism were associated with worse outcomes. Correcting these laboratory parameters may improve patients’ survival in the HD population.