[Circadian rhythm of blood pressure and obesity--blood pressure variation and obesity].
BACKGROUND
The association between obesity and arterial hypertension has been established in a great number of studies. Our objective was to investigate whether circadian rhythm of blood pressure is disturbed among obese people.


METHODS
In this cros-sectional, randomized study, Schiller BR-102 device was used for ambulatory blood pressure monitoring. One hundred and twenty outpatients were divided into three randomized groups: obese body mass index 30 kg/m2 (52 patients), overweight (28 patients), with body mass index 25.0-29.9 kg/m2 and normal weight (control group) (48 patients), with body mass index 18.5-24.9 kg/m2. In all patients we investigated the following blood pressure parameters: average blood pressure (total, day-time and night-time), maximal blood pressure and dipping or non-dipping blood pressure pattern during night (for systolic and diastolic blood pressure, respectively).


RESULTS
In body mass index beyond 30 kg/m2 only systolic blood pressure parameters were significantly higher--average blood pressure--during daytime (P = 0.034) and during night (P = 0.014); maximal blood pressure (P = 0.001). In body mass index beyond 30 kg/m2, absence of normal blood pressure during night was significantly more often registered (P = 0.007).


CONCLUSIONS
The non-dipping blood pressure pattern and increase of systolic blood pressure only reveal hyperactivation of sympathetic nervous system as a leading patophysiological mechanism causing arterial hypertension in obese patients.
Despotović
Nebojsa
N
Centar za kardiovaskularne bolesti, KBC Zvezdara, 11000 Beograd, Ul. Dimitrija Tucovića 161. ndsp@beotel.yu
D001794:Blood Pressure; D015992:Body Mass Index; D002940:Circadian Rhythm; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*