Fissuh Yemane Hailu, Nega Getachew Beyene, Hailay Azmera
Biostatistics, Department of Statistics, College of Natural and Computational Sciences, Aksum University, Axum, Tigray, Ethiopia.
Department of Statistics, College of Natural and Computational Sciences, Mekelle University, Tigray, Ethiopia.
SAGE Open Med. 2025 Sep 13;13:20503121251360864. doi: 10.1177/20503121251360864. eCollection 2025.
Chronic kidney disease, or renal failure, is a public health problem with an estimated prevalence of 8%-16% worldwide. This study was conducted to investigate the evolution of hematocrit levels over time in renal patients after transplantation and to determine how the evolution of hematocrit levels depends on the patients' age, sex, and other factors.
The main objective of this study was to employ a mixed-effects model to examine the unbalanced longitudinal evolution of hematocrit levels in chronic kidney failure patients.
This longitudinal study included 1160 patients who received a renal transplant. These patients were followed for at most 10 years. The hematocrit level was considered the response, while the covariates were time in years, sex, and age of the patients. Different statistical methods, such as explanatory analysis, multivariate regression, two-stage analysis, and linear mixed-effects models, were employed to explore the evolution of hematocrit over time.
The results revealed that hematocrit levels in kidney transplant patients evolve. The sex and age of the patient significantly affect the evolution of hematocrit levels. Males tend to have a greater increase in hematocrit levels over time than females do. Hematocrit levels tend to increase with increasing age. Furthermore, cardiovascular problems before transplant and rejection symptoms did not significantly affect the evolution of hematocrit levels.
Hematocrit levels evolve, and this evolution follows a quartic time effect. The change in hematocrit levels varies according to the sex and age of the patient after a kidney transplant. Patients with low hematocrit levels tend to have a greater increase over time.
慢性肾脏病，即肾衰竭，是一个公共卫生问题，据估计全球患病率为8%-16%。本研究旨在调查肾移植患者移植后血细胞比容水平随时间的变化情况，并确定血细胞比容水平的变化如何取决于患者的年龄、性别和其他因素。
本研究的主要目的是采用混合效应模型来检验慢性肾衰竭患者血细胞比容水平的不平衡纵向变化。
这项纵向研究纳入了1160例接受肾移植的患者。这些患者最多随访10年。将血细胞比容水平视为反应变量，而协变量为患者的年龄（以年计）、性别和时间。采用不同的统计方法，如解释性分析、多元回归、两阶段分析和线性混合效应模型，来探讨血细胞比容随时间的变化情况。
结果显示肾移植患者的血细胞比容水平会发生变化。患者的性别和年龄显著影响血细胞比容水平的变化。随着时间的推移，男性的血细胞比容水平往往比女性有更大的升高。血细胞比容水平往往随年龄增长而升高。此外，移植前的心血管问题和排斥症状并未显著影响血细胞比容水平的变化。
血细胞比容水平会发生变化，且这种变化呈现四次时间效应。肾移植后，血细胞比容水平的变化因患者的性别和年龄而异。血细胞比容水平较低的患者随着时间的推移往往有更大的升高幅度。
