Out of control: accelerated aging in uremia.

Next to a high morbidity, patients with end-stage renal failure (ESRD) suffer from a complex spectrum of clinical manifestations. Both the phenotype of patients with ESRD as well as the pathophysiology of uremia show interesting parallels with the general aging process. Phenotypically, patients with ESRD have an increased susceptibility for both cardiovascular as well as infectious disease and show a reduction in functional capacity as well as muscular mass (sarcopenia), translating into a high prevalence of frailty also in younger patients. Pathophysiologically, the immune dysfunction, telomere attrition and the presence of low-grade inflammation in uremic patients also show parallels with the aging process. System models of aging, such as the homeodynamic model and reliability theory of Gavrilov may also have relevance for ESRD. The reduction in the redundancy of compensatory mechanisms and the multisystem impairment in ESRD explain the rapid loss of homeodynamic/homeostatic balance and the increased susceptibility to external stressors in these patients. System theories may also explain the relative lack of success of interventions focusing on single aspects of renal disease. The concept of accelerated aging, which also shares similarities with other organ diseases, may be of relevance both for a better understanding of the uremic process, as well as for the design of multidimensional interventions in ESRD patients, including an important role for early rehabilitation. Research into processes akin to both aging and uremia may result in novel therapeutic approaches.