[The relationship between overweight, life style and casual and 24-hour pressures in a population of male subjects with mild hypertension. The results of the HARVEST study]

Abstract

Aim of the study: To evaluate the relationship of coffee use, smoking, physical inactivity, alcohol intake and overweight with casual and ambulatory blood pressure in a large population of borderline to mild hypertensive subjects.

Methods: Six hundred and thirty men with a mean (+/- SE) age of 33 +/- 0.4 years (range = 18-45 years) and a mean office blood pressure of 146 +/- 0.4/94 +/- 0.2 mm Hg, participating in the multicentre HARVEST study, were divided into three categories according to: coffee consumption (0 cups, 1-3 cups, > 3 cups/day), number of cigarettes smoked per day (0, 1-10, 11-20), degree of physical activity (no activity, regular training, competitive activity), alcohol intake (no alcohol, < 50 g, > or = 50 g/day) and body mass index (tertiles). All patients underwent non invasive ambulatory blood pressure monitoring with either the A&D TM-2420 model 7 or the Spacelabs 90207 monitor. Moreover, 24-hour urine collection was made for epinephrine and norepinephrine assessment (n = 611).

Results: Twenty-four-hour systolic blood pressure was higher in the coffee drinkers than the nondrinkers (+2.6 mm Hg in the moderate drinkers). Instead, 24-hour diastolic blood pressure was mainly influenced by overweight (3.2 mm Hg difference between the low and high BMI tertiles) and physical inactivity (3.2 mm Hg difference between the sedentary men and the athletes). Generally, the association of the above factors was stronger with ambulatory than with office blood pressure, whereas alcohol intake was only related to office diastolic blood pressure. However, in a multivariate regression analysis alcohol use did not show an independent effect on either office or ambulatory blood pressure. Smoking showed a different effect on office and ambulatory blood pressure. In fact, office blood pressure was higher in the nonsmokers, while 24-hour blood pressure was higher in the smokers. Smoking, coffee and physical inactivity were associated with sympathetic overactivity, as documented by increased urinary catecholamines output.

Conclusions: The results of the present study indicate that overweight and behavioural factors affect 24-hour blood pressure to a larger extent than office blood pressure does. This is likely to be due to their effect on the sympathetic nervous system activity, which would enhance the blood pressure response to daily life stressors.