End-Stage Renal Disease, Inflammation and Cardiovascular Outcomes

Despite marked improvements in renal replacement therapy during the last 30 years, the age-adjusted mortality rate in end-stage renal disease (ESRD) patients is still unacceptably high and comparable to that of many malignancies. Cardiovascular disease (CVD) remains the major cause of morbidity and mortality in ESRD patients. However, traditional risk factors can only partially explain the high premature cardiovascular burden in this population. Nontraditional risk factors, including persistent low-grade inflammation, are critical in the pathogenesis of atherosclerosis, vascular calcification, and other causes of CVD and may also contribute to protein-energy wasting and other complications in chronic kidney disease (CKD) patients. Inflammatory biomarkers, such as high sensitivity C-reactive protein and interleukin-6, independently predict mortality in these patients. The causes of inflammation in CKD are multifactorial and include imbalance between increased production (due to multiple sources of inflammatory stimuli such as oxidative stress, acidosis, volume overload, co-morbidities, especially infections, genetic and epigenetic influences, and the dialysis procedure) and inadequate removal (due to decreased glomerular filtration rate or in ESRD patients, inadequate dialytic clearance) of pro-inflammatory cytokines. Though there are currently no established guidelines for the treatment of low-grade inflammation in ESRD patients, several strategies have been proposed, such as lifestyle modifications, pharmacological treatment, and optimization of dialysis. Further studies on pathways involved in pathogenic processes of inflammation in ESRD, and long-term effects of anti-inflammatory interventions targeting production or removal of cytokines or both on premature CVD and clinical outcomes in this patient group are warranted.