Gender Differences in Dose of Erythropoietin to Maintain Hemoglobin Target in Hemodialysis Patients

Effect of Preoperative Recombinant Human Erythropoietin on the Need for Blood Transfusion and Surgical Outcomes in Adult Patients Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis with Trial Sequential Analysis

This study aimed to examine the value of preoperative recombinant human erythropoietin (rhEPO) administration to adults undergoing elective cardiac surgery. Databases were searched for randomized controlled trials (RCTs) comparing rhEPO plus standard treatment versus standard treatment only. Primary outcomes were the need for and volume of homologous blood transfusion (HBT). Secondary outcomes were the lengths of intensive care unit (ICU) and hospital stay and the incidence of major adverse events. There was very low certainty that rhEPO is associated with a reduction in the need for HBT, with a number needed to treat of 5.6 (95% confidence interval [CI], 3.9-12.5), and low certainty that it is associated with a moderate reduction in HBT volume (Hedges g = -0.55; 95% CI, -0.79 to -0.32). Meta-regression revealed that studies with a higher proportion of females or older patients demonstrated less benefit of rhEPO in terms of reduced consumption of HBT. Trial sequential analysis showed that rhEPO was superior to standard treatment only for reducing the need for and volume of HBT. Regarding secondary outcomes, there was moderate certainty that rhEPO is associated with a limited reduction in the length of ICU (Hedges g = -0.10; 95% CI, -0.19 to -0.01) and hospital stay (Hedges g = -0.13; 95% CI = -0.25 to -0.02), and low certainty for increased risk of myocardial infarction, with a number needed to harm of 36.1 (95% CI, 17.9-127.4). More well-designed, adequately powered RCTs are needed to draw conclusions regarding the value of rhEPO.

Individualization of the Dosage Regimen of Erythropoietin is Crucial in End-stage Renal Disease Patients

The objective of this study was to understand the utilization pattern of erythropoietin in end-stage renal disease patients, along with the effect of body weight and sex on the patients' responses. In this retrospective single-center study, 120 patients were included who were on a once weekly (n = 79), twice weekly (n = 37), or thrice weekly (n = 4) regimen. The doses of erythropoiesis-stimulating agents (ESA) were collected, and the erythropoietin resistance index (ERI) was determined. The Kruskal-Wallis test was used to evaluate the dose schedules, and the once-weekly regimen produced a greater response (P = 0.001). The asymptotic significance of Pearson's Chi-square-test equating the mean ERI and body mass index (BMI) was 0.034. No statistically significant correlation was estimated between sex and mean ERI (P = 0.201). Our study demonstrated that the once-weekly regimen dominated over the others in terms of efficacy, and individuals with a higher BMI were found to respond better to the ESA therapy.

Gender and Renal Insufficiency: Opportunities for Their Therapeutic Management?

Acute kidney injury (AKI) is a major clinical problem associated with increased morbidity and mortality. Despite intensive research, the clinical outcome remains poor, and apart from supportive therapy, no other specific therapy exists. Furthermore, acute kidney injury increases the risk of developing chronic kidney disease (CKD) and end-stage renal disease. Acute tubular injury accounts for the most common intrinsic cause of AKI. The main site of injury is the proximal tubule due to its high workload and energy demand. Upon injury, an intratubular subpopulation of proximal epithelial cells proliferates and restores the tubular integrity. Nevertheless, despite its strong regenerative capacity, the kidney does not always achieve its former integrity and function and incomplete recovery leads to persistent and progressive CKD. Clinical and experimental data demonstrate sexual differences in renal anatomy, physiology, and susceptibility to renal diseases including but not limited to ischemia-reperfusion injury. Some data suggest the protective role of female sex hormones, whereas others highlight the detrimental effect of male hormones in renal ischemia-reperfusion injury. Although the important role of sex hormones is evident, the exact underlying mechanisms remain to be elucidated. This review focuses on collecting the current knowledge about sexual dimorphism in renal injury and opportunities for therapeutic manipulation, with a focus on resident renal progenitor stem cells as potential novel therapeutic strategies.

Cerebral blood flow regulation in end-stage kidney disease

Patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD) experience an increased risk of cerebrovascular disease and cognitive dysfunction. Hemodialysis (HD), a major modality of renal replacement therapy in ESKD, can cause rapid changes in blood pressure, osmolality, and acid-base balance that collectively present a unique stress to the cerebral vasculature. This review presents an update regarding cerebral blood flow (CBF) regulation in CKD and ESKD and how the maintenance of cerebral oxygenation may be compromised during HD. Patients with ESKD exhibit decreased cerebral oxygen delivery due to anemia, despite cerebral hyperperfusion at rest. Cerebral oxygenation further declines during HD due to reductions in CBF, and this may induce cerebral ischemia or "stunning." Intradialytic reductions in CBF are driven by decreases in cerebral perfusion pressure that may be partially opposed by bicarbonate shifts during dialysis. Intradialytic reductions in CBF have been related to several variables that are routinely measured in clinical practice including ultrafiltration rate and blood pressure. However, the role of compensatory cerebrovascular regulatory mechanisms during HD remains relatively unexplored. In particular, cerebral autoregulation can oppose reductions in CBF driven by reductions in systemic blood pressure, while cerebrovascular reactivity to CO₂ may attenuate intradialytic reductions in CBF through promoting cerebral vasodilation. However, whether these mechanisms are effective in ESKD and during HD remain relatively unexplored. Important areas for future work include investigating potential alterations in cerebrovascular regulation in CKD and ESKD and how key regulatory mechanisms are engaged and integrated during HD to modulate intradialytic declines in CBF.