[Absence of nocturnal dipping is associated with stroke and myocardium infarction].
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.
Vaz-de-Melo
Renan Oliveira
RO
Hospital de Base, Faculdade Estadual de Medicina de São José do Rio Preto, São José do Rio Preto, SP. renanovmelo@gmail.com
Toledo
Juan Carlos Yugar
JC
Loureiro
Afonso Augusto Carvalho
AA
Cipullo
José Paulo
JP
Moreno Júnior
Heitor
H
Martin
José Fernando Vilela
JF
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*