title: Diagnostic tools for hypertension and salt sensitivity testing.
abstract: OBJECTIVE
  One-third of the world's population has hypertension and it is responsible for almost 50% of deaths from stroke or coronary heart disease. These statistics do not distinguish salt-sensitive from salt-resistant hypertension or include normotensives who are salt-sensitive even though salt sensitivity, independent of blood pressure, is a risk factor for cardiovascular and other diseases, including cancer. This review describes new personalized diagnostic tools for salt sensitivity.
  
  
  RESULTS
  The relationship between salt intake and cardiovascular risk is not linear, but rather fits a J-shaped curve relationship. Thus, a low-salt diet may not be beneficial to everyone and may paradoxically increase blood pressure in some individuals. Current surrogate markers of salt sensitivity are not adequately sensitive or specific. Tests in the urine that could be surrogate markers of salt sensitivity with a quick turn-around time include renal proximal tubule cells, exosomes, and microRNA shed in the urine.
  
  
  CONCLUSIONS
  Accurate testing of salt sensitivity is not only laborious but also expensive, and with low patient compliance. Patients who have normal blood pressure but are salt-sensitive cannot be diagnosed in an office setting and there are no laboratory tests for salt sensitivity. Urinary surrogate markers for salt sensitivity are being developed.
authors.affiliation: Department of Pathology, The University of Virginia, Health Sciences Center, Charlottesville, Virginia, USA.
authors.forename: Robin A
authors.initials: RA
authors.lastname: Felder
authors.forename: Marquitta J
authors.initials: MJ
authors.lastname: White
authors.forename: Scott M
authors.initials: SM
authors.lastname: Williams
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Jose
mesh_terms: D015415:Biomarkers; D001794:Blood Pressure / Q000187:drug effects* / Q000235:genetics; D055354:Exosomes; D054771:G-Protein-Coupled Receptor Kinase 4 / Q000235:genetics; D005820:Genetic Testing; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000235:genetics*; D007687:Kidney Tubules, Proximal / Q000166:cytology; D017673:Sodium Chloride, Dietary / Q000009:adverse effects*
chemical_list: D015415:Biomarkers; D017673:Sodium Chloride, Dietary; D054771:G-Protein-Coupled Receptor Kinase 4; C517855:GRK4 protein, human