title: [Absence of nocturnal dipping is associated with stroke and myocardium infarction].
abstract: BACKGROUND
  The arterial hypertension varies in according to the circadian cycle, presenting physiologic fall of blood pressure (BP) during sleep (dipping). The absence of this fall or its increase associates to higher incidence of target-organ damages.
  
  
  OBJECTIVE
  To analyze the prevalence of dipping in hypertensive individuals, to correlate dipping to the blood pressure levels, clinic, and socio-demographic factors, and biochemical characteristics and to associate it cardiovascular events (stroke and myocardial infarction).
  
  
  METHODS
  Hypertensive individuals were submitted to the ambulatory blood pressure monitoring. Presence of dipper was defined as fall >10% of the systolic BP of the day for sleep.
  
  
  RESULTS
  163 evaluated patients were divided in dippers (D, n=53) and nondippers (ND, n=110). Between the groups there was not significant difference to the age, sex, race, time of hypertension, glycemia, LDL-cholesterol, total cholesterol, triglycerides, schooling, smoking, and history of diabetes. D presented BP higher than the ND during the day and lower during sleep. ND had higher body mass index (BMI) (p=0.0377), lower level of HDL-cholesterol (p=0.0189), and higher pulse pressure during sleep (p=0.0025). History of stroke alone (p=0,046) and combined with myocardial infarction (p=0.032) were more frequent in nondippers individuals. In the logistic regression, only ND was associated independently with stroke or myocardial infarction.
  
  
  CONCLUSIONS
  ND was associated in an independent way with the target-organ damages analyzed, what demonstrates its importance and strengthens the necessity of more aggressive treatment with objective to reach BP goals e, consequently, to prevent the development of new cardiologic and cerebrovascular events.
authors.affiliation: Hospital de Base, Faculdade Estadual de Medicina de São José do Rio Preto, São José do Rio Preto, SP. renanovmelo@gmail.com
authors.forename: Renan Oliveira
authors.initials: RO
authors.lastname: Vaz-de-Melo
authors.forename: Juan Carlos Yugar
authors.initials: JC
authors.lastname: Toledo
authors.forename: Afonso Augusto Carvalho
authors.initials: AA
authors.lastname: Loureiro
authors.forename: José Paulo
authors.initials: JP
authors.lastname: Cipullo
authors.forename: Heitor
authors.initials: H
authors.lastname: Moreno Júnior
authors.forename: José Fernando Vilela
authors.initials: JF
authors.lastname: Martin
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D001938:Brazil / Q000453:epidemiology; D002940:Circadian Rhythm / Q000502:physiology*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology*; D012959:Socioeconomic Factors; D020521:Stroke / Q000209:etiology*