Article

Impact of smoking and smoking cessation on arterial stiffness and aortic wave reflection in hypertension.

Department of Pharmacology and Therapeutics, Trinity Centre for Health Sciences, St James's Hospital, Dublin 8, Ireland.
Hypertension (Impact Factor: 6.87). 05/2007; 49(5):981-5. DOI: 10.1161/HYPERTENSIONAHA.107.087338
Source: PubMed

ABSTRACT Cigarette smoking is an important modifiable cardiovascular risk factor and pathophysiological mechanisms may include a stiff vascular tree. Although smokers have stiffer arteries, whether smoking cessation is associated with reduced arterial stiffness is not known. We compared never-treated patients with essential hypertension (n=554) aged 18 to 80 years (56% females) classified as current smokers (n=150), ex-smokers (n=136), and nonsmokers (n=268). Ex-smokers were categorized into <1 year, >1 and <10 years, and >10 years of smoking cessation. Measurements included aortic stiffness, assessed as pulse wave velocity (Complior), wave reflection (augmentation index [AIx]), and transit time (T(R)) (Sphygmocor). Current and ex-smokers had significantly higher pulse wave velocity and AIx compared with nonsmokers (pulse wave velocity for current smokers: 10.7+/-0.2; ex-smokers: 10.6+/-0.2; nonsmokers: 9.9+/-0.1 m/s; P<0.001; AIx for current smokers: 31+/-1; ex-smokers: 30+/-1; nonsmokers: 27+/-0.8%; P<0.05), whereas T(R) was lower in current and ex-smokers compared with nonsmokers (T(R) for current smokers: 131+/-1.0; ex-smokers: 135+/-1; nonsmokers: 137+/-0.8 m/s; P<0.0001). There was a significant linear relationship between smoking status and pulse wave velocity (P<0.001), AIx (P<0.001), and T(R) (P<0.001), even after adjusting for age, sex, mean arterial pressure, heart rate, and body mass index. In ex-smokers, duration of smoking cessation had a significant linear relationship with improvement in pulse wave velocity (P<0.001), AIx (P<0.001), and T(R) (P<0.001), with arterial stiffness parameters returning to nonsignificant levels after a decade of smoking cessation.

1 Bookmark
 · 
126 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: We tested the hypotheses that smoking-induced changes in vascular mechanics would be detected earlier in the lumped properties of peripheral vascular beds, which include the properties of microvasculature, than in the local properties of central conduits, and that such changes are reversible with lifestyle changes that include smoking cessation and exercise. Vascular measures were made in 53 young (18-40 years) female smokers and 25 age-matched non-smokers. Twenty-two of the smokers were tested before and after a 14-week smoking cessation program and, of these, 13 were tested again after 52 weeks of smoking cessation. Compared with non-smokers, lumped forearm vascular bed compliance (C: mL/mm Hg) was lower, while lumped viscoelasticity (K: mm Hg/(mL·min)) and resistance (R: mm Hg/(mL·min)) were higher in the smoker group. Neither the carotid-to-toe pulse wave velocity nor local carotid artery elasticity indices were different between groups. Compared with non-smokers, brachial artery distensibility was less, and other markers of stiffness higher, in the smoker group. At 14 and 52 weeks of smoking cessation, forearm vascular R was reduced and C was increased while K was unchanged. The changes in C and R occurred while maintaining a constant R×C value, which represents a dynamic time constant. Thus, early changes in K were observed in the forearm vascular bed of smokers, which were not reflected in the local properties of central conduit vessels. Forearm C, but not K, was reversed following smoking cessation, a finding that may represent a persistent effect of smoking on the intercellular matrix of the vessel wall.
    Applied Physiology Nutrition and Metabolism 05/2014; 39(5):572-80. · 2.01 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cigarette smoking is an important modifiable cardiovascular risk factor associated with increased stiffness of the large arteries in adulthood. This study aimed to 1) evaluate arterial distensibility and echocardiographic measures in adolescent smokers before and after participation in a successful smoking cessation program and to 2) compare the findings obtained with data from a control population of healthy non-smokers. A total of 31 young smoking subjects (58.1% male; range: 11-18 years old; mean: 16.5±1.4 years old; mean tobacco consumption: 2.6±0.6 years) were examined before commencing and after taking part for at least 1 year in a smoking cessation program (mean: 1.4±0.3 years). Arterial stiffness was measured using the previously validated QKd100-60 method. Twenty-four-hour ambulatory blood pressure monitoring and transthoracic echocardiography were also performed. (Smokers before abuse cessation vs. smokers after abuse cessation) systolic blood pressure: p<0.004; diastolic blood pressure: p<0.02; mean blood pressure: p<0.01; QKd100-60 value: 183±5 vs. 196±3 msec, p<0.009; p = ns for all echocardiographic parameters. (Smokers after abuse cessation vs. controls) systolic blood pressure: p<0.01; diastolic blood pressure: p<0.03; mean blood pressure: p<0.02; QKd100-60 value: 196±3 vs. 203±2 msec, p<0.04; p<0.02, p<0.01, and p<0.05 for the interventricular septum, posterior wall, and left ventricular mass, respectively. Despite successful participation in a smoking cessation program, arterial distensibility improved but did not normalize. This finding underlines the presence of the harmful effect of arterial rigidity in these individuals, despite their having quit smoking and their young ages, thus resulting in the subsequent need for a lengthy follow-up period.
    Clinics (São Paulo, Brazil) 04/2014; 69(4):219-24. · 1.59 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To assess the association between aortic pulse wave velocity (PWV) as a marker of arterial stiffness and diffusion tensor imaging of brain white matter integrity in patients with type 1 diabetes using advanced magnetic resonance imaging (MRI) technology. Forty-one patients with type 1 diabetes (23 men, mean age 44 ± 12 years, mean diabetes duration 24 ± 13 years) were included. Aortic PWV was assessed using through-plane velocity-encoded MRI. Brain diffusion tensor imaging (DTI) measurements were performed on 3-T MRI. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated for white and grey matter integrity. Pearson correlation and multivariable linear regression analyses including cardiovascular risk factors as covariates were assessed. Multivariable linear regression analyses revealed that aortic PWV is independently associated with white matter integrity FA (β = -0.777, p = 0.008) in patients with type 1 diabetes. This effect was independent of age, gender, mean arterial pressure, body mass index, smoking, duration of diabetes and glycated haemoglobin levels. Aortic PWV was not significantly related to grey matter integrity. Our data suggest that aortic stiffness is independently associated with reduced white matter integrity in patients with type 1 diabetes. • Aortic stiffness is associated with brain injury. • Aortic stiffness exposes small vessels to high pressure fluctuations and flow. • Aortic stiffness is associated with microvascular brain injury in diabetes. • This suggests a vascular contribution to early subtle microstructural deficits.
    European Radiology 05/2014; · 4.34 Impact Factor

Full-text

View
99 Downloads
Available from
May 20, 2014