title: Cerebrospinal fluid adrenomedullin concentration correlates with hyponatremia and delayed ischemic neurological deficits after subarachnoid hemorrhage.
abstract: BACKGROUND
  Adrenomedullin (AM), a vasorelaxant peptide, is secreted into the cerebrospinal fluid (CSF) from the choroid plexus and can exert natriuretic effects in the kidney. CSF AM concentration is elevated 7-10 days after the onset of aneurysmal subarachnoid hemorrhage (SAH). The aim of the present study was to determine whether CSF AM concentrations correlate with hyponatremia and delayed ischemic neurological deficits (DIND) after SAH.
  
  
  METHODS
  CSF and plasma concentrations of AM, brain natriuretic peptide, and atrial natriuretic peptide concentrations were measured in 32 patients with SAH who underwent aneurysmal clipping within 48 h of onset. CSF and blood samples were obtained from these patients during the early period (days 1-3, day 0 being regarded as the day of SAH onset) and the late period (days 8-10).
  
  
  RESULTS
  In all patients, AM concentration during the early and late periods was significantly higher in the CSF than in the plasma (p = 0.0028 and p < 0.0001). In addition, CSF AM concentration was significantly higher during the late period than during the early period (p < 0.0001). Hyponatremia (plasma sodium <135 mmol/l) was present in 11 patients (34.4%) during the late period, and DIND developed in 6 patients (19%) between day 5 and day 13. Logistic regression analysis demonstrated that late-period CSF AM concentration correlated with hyponatremia and DIND (95% CI: 1.003-1.069, p = 0.0074 and 95% CI: 1.003-1.052, p = 0.0108).
  
  
  CONCLUSIONS
  The present study demonstrated that CSF AM during the late period following SAH correlates with hyponatremia and DIND.
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Morioka, Japan. yokubo@iwate-med.ac.jp
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kubo
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kakino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kashimura
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoshida
authors.forename: Akira
authors.initials: A
authors.lastname: Ogawa
mesh_terms: D053607:Adrenomedullin / Q000097:blood / Q000134:cerebrospinal fluid*; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood; D002545:Brain Ischemia / Q000097:blood / Q000134:cerebrospinal fluid / Q000209:etiology*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000097:blood / Q000134:cerebrospinal fluid / Q000209:etiology*; D002532:Intracranial Aneurysm / Q000097:blood / Q000134:cerebrospinal fluid* / Q000150:complications; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D013345:Subarachnoid Hemorrhage / Q000097:blood / Q000134:cerebrospinal fluid* / Q000150:complications; D013997:Time Factors
chemical_list: D020097:Natriuretic Peptide, Brain; D053607:Adrenomedullin; D009320:Atrial Natriuretic Factor