Impact of smoking cessation on ambulatory blood pressure and heart rate in postmenopausal women

Background: Smoking and hypertension interact to increase the incidence of cardiovascular disease: however, little is known about the effects of smoking cessation on blood pressure (BP) control. We prospectively evaluated the impact of smoking cessation on clinic and ambulatory BP and heart rate (HR) in stage 1 hypertensive and normotensive postmenopausal women. Methods: A total of 66 women were randomly assigned using a 3:1 randomization scheme to immediate smoking cessation or to a wait list control group. Clinic and ambulatory BP and HR, and 24-h urinary catecholamine concentrations were obtained at baseline and again at 6 weeks. Carbon monoxide levels and self-report were used to assess compliance with smoking cessation. Results: Ambulatory monitoring showed that the awake SBP decreased by 3.6 +/- 1.9 mm Hg in the treated subjects who quit smoking (n = 19), whereas in the control group (n = 15) there was an increase of 1.7 +/- 2.4 mm Hg (P = .045). Awake HR decreased after smoking cessation by 7 +/- 1 beats/min and did not change (0 +/- 1 beat/min) in the control group (P = .001). Blood pressure and HR did not significantly change during sleep after smoking cessation. Changes in the awake HR correlated with changes in urinary epinephrine concentrations (r = 0.58, P = .001), and norepinephrine concentrations (r = 0.45, P = .001), There was no significant change in clinic systolic BP, diastolic BP, or HR between groups. Conclusions: Smoking cessation reduces systolic BP and HR during the daytime, when patients typically smoke. These hemodynamic changes are due in part to reductions in sympathetic nervous system activity. Am J Hypertens 2001; 14:942-949 (C) 2001 American Journal of Hypertension, Ltd.