INTERACTIVE EFFECT OF CIGARETTES AND COFFEE ON DAYTIME SYSTOLIC BLOOD-PRESSURE IN PATIENTS WITH MILD ESSENTIAL-HYPERTENSION

Objective: To test the hypothesis that moderate smoking (fewer than 20 cigarettes/day) and coffee consumption have an interactive effect on ambulatory blood pressure. Design: A case-control study. Setting: Pati ents in the multicentre Hypertension Ambulatory Venetia Study, northea stern Italy. Subjects: Six hundred and forty-three men and 244 women w ith borderline-to-mild hypertension that had never been treated, subdi vided according to their smoking status (non-smokers versus smokers) a nd their habitual consumption of coffee (0, 1-3, or 4+ cups/day). Main outcome measures: Office blood pressure, ambulatory blood pressure, u rinary adrenaline and noradrenaline levels according to smoking status , coffee consumption and their interaction. Results: In the men, dayti me systolic blood pressure (SEP) was significantly higher in the smoke rs than in the non-smokers and in the coffee drinkers than in the othe rs. Moreover, two-way analysis of covariance revealed a significant in teraction between smoking status and coffee consumption: the daytime S EP in smokers who drank 4+ cups/day of coffee was 6.0 mmHg higher than that of non-smokers who abstained from coffee. Conversely, office blo od pressure was lower in the smokers than in the non-smokers and was s imilar in the coffee drinkers and the others. Coffee consumption had a significant effect on urinary adrenaline. Similar results were obtain ed in the women. Conclusions: In contrast with what is shown by office blood pressure measurement, moderate smokers and coffee drinkers with mild hypertension have significantly higher daytime SEP levels than n on-smokers and those who do not drink coffee. Cigarettes and coffee ha ve an interactive effect on daytime SEP in young patients with mild es sential hypertension.