title: Plasma endothelin-1 level is related to renal function and smoking status but not to blood pressure: an epidemiological study.
abstract: OBJECTIVE
  Endothelin-1 (ET-1) is a potent vasoconstrictor derived from the endothelium. Several studies with small numbers of humans have showed high plasma ET-1 levels in hypertension, but other studies have not. Furthermore, it has been shown in a small number of subjects that ET-1 is elevated in uraemic patients. However, there have been no epidemiological surveys as to whether ET-1 level is related to hypertension or end-organ damage.
  
  
  METHODS
  A total of 1492 subjects received a health examination in 1999. The data for fasting ET-1 of 1450 individuals were obtained. A specific radioimmunoassay was used to measure ET-1 levels. We also measured body mass index (BMI), systolic and diastolic blood pressure (BP), haemoglobin A1c, cholesterol, blood urea nitrogen (BUN), creatinine and uric acid. We performed carotid B-mode ultrasonography and electrocardiography. Smoking habit was evaluated by questionnaire.
  
  
  RESULTS
  Mean ET-1 was 4.93 +/- 1.73 pg/ml in men and 4.84 +/-1.54 pg/ml in women. ET-1 increased with age (P < 0.001). Systolic (P < 0.001) and diastolic (P < 0.05) BP, hypertensive medication (P < 0.05), BUN (P < 0.01), creatinine (P < 0.001), uric acid (P < 0.001), intimal-medial thickness (P < 0.001), smoking (P < 0.05) and age (P < 0.001), were significantly associated with ET-1 by univariate analysis. By the use of multiple stepwise regression analysis, age (P < 0.001), creatinine (P < 0.001) and smoking (P < 0.05) remained significant. However, no relation was shown between ET-1 and BP.
  
  
  CONCLUSIONS
  Our data suggest that high ET-1 is not related to hypertension, but to subclinical renal dysfunction and smoking.
authors.affiliation: The Third Department of Internal Medicine and The Cardiovascular Research Institute, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hirai
authors.forename: Hisashi
authors.initials: H
authors.lastname: Adachi
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Fujiura
authors.forename: Akiko
authors.initials: A
authors.lastname: Hiratsuka
authors.forename: Mika
authors.initials: M
authors.lastname: Enomoto
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Imaizumi
mesh_terms: D000367:Age Factors; D000368:Aged; D001794:Blood Pressure; D015992:Body Mass Index; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D003404:Creatinine / Q000097:blood; D004562:Electrocardiography; D019332:Endothelin-1 / Q000097:blood*; D016021:Epidemiologic Studies; D005215:Fasting; D005260:Female; D006304:Health Status; D006801:Humans; D007564:Japan; D007668:Kidney / Q000502:physiology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects* / Q000097:blood; D011795:Surveys and Questionnaires; D014463:Ultrasonography
chemical_list: D019332:Endothelin-1; D003404:Creatinine