title: Red blood cell distribution width in 'non-dippers' versus 'dippers'.
abstract: OBJECTIVE
  Because both high red cell distribution width (RDW) and non-dipping hypertension are closely related to adverse cardiovascular outcomes and higher inflammatory status, we aimed to investigate whether there is any relationship between RDW and dipping/non-dipping hypertension status.
  
  
  METHODS
  The present study involved 123 hypertensive patients and 65 age- and gender-matched healthy, normotensive subjects. Hypertensive patients were divided into two groups: 56 dipper patients (20 males, mean age 51.9 ± 15.3 years) and 67 non-dipper patients (27 males, mean age 55.6 ± 15.0 years). If the systolic daytime blood pressure (BP) of the patients decreased by at least 10% during the nighttime, these subjects were 'dippers', and all other subjects were 'non-dippers'.
  
  
  RESULTS
  Both dipper patients and non-dipper patients had higher levels of RDW compared to normotensives (13.5 ± 0.89 and 14.1 ± 1.33 vs. 13.0 ± 1.42%, p = 0.027 and p < 0.001, respectively). Also RDW values in non-dippers were statistically higher compared to those in dippers (p = 0.008). Although there were negative correlations between RDW values and nocturnal systolic BP fall (p = 0.027, r = -0.199) and diastolic BP fall (p = 0.383, r = -0.079) in all hypertensive patients, these correlations did not reach a statistically significant level.
  
  
  CONCLUSIONS
  Our study demonstrates that non-dippers have high RDW levels compared to both dippers and controls.
authors.affiliation: Department of Cardiology, Kastamonu Munif Islamoglu State Hospital, Kastamonu, Turkey. drgunebakmaz@yahoo.com
authors.forename: Ozgur
authors.initials: O
authors.lastname: Gunebakmaz
authors.forename: Mehmet G
authors.initials: MG
authors.lastname: Kaya
authors.forename: Mustafa
authors.initials: M
authors.lastname: Duran
authors.forename: Mahmut
authors.initials: M
authors.lastname: Akpek
authors.forename: Deniz
authors.initials: D
authors.lastname: Elcik
authors.forename: Namık Kemal
authors.initials: NK
authors.lastname: Eryol
mesh_terms: D000704:Analysis of Variance; D001794:Blood Pressure / Q000502:physiology; D016022:Case-Control Studies; D002940:Circadian Rhythm; D004909:Erythrocyte Indices / Q000502:physiology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged