RESUMEN
Arginine vasopressin (AVP), also known as antidiuretic hormone (ADH), is released in response to osmotic and non-osmotic stimuli and plays a key role in many physiologic and pathologic processes. The main function of AVP is the control of fluid homeostasis by inducing water conservation by the kidney, but it also stimulates arteriolar vasoconstriction and the release of adrenocorticotropic hormone (ACTH). These actions are mediated by different AVP receptors located on various target cells. Produced in hypothalamus from a larger precursor, pre-proAVP, AVP is produced in equimolar amounts to copeptin, a glycopeptide with yet unknown biologic function. Copeptin remains stable in plasma and its circulating concentrations correlate directly with those of AVP. Because AVP is unstable in isolated plasma or serum and its half-life is short, copeptin has become an easily measured surrogate marker reflecting vasopressin concentration. Recently, associations between high circulating copeptin and decline in glomerular filtration rate as well as greater risk of new-onset chronic kidney disease (CKD) have been reported. In addition, copeptin has been shown to be associated with increased risk of complications such as myocardial infarction, heart failure, diabetes mellitus and metabolic syndrome. In this brief review, studies on the prognostic value of copeptin measurement in the general population and in CKD are presented and discussed.