title: Improvement of aortic reflection wave responses 6 months after stopping smoking: a prospective study.
abstract: BACKGROUND
  Cigarette smoking is one important preventable cause of cardiovascular illness that has been associated with increased stiffness of large arteries and wave reflection, which are independent predictors of cardiovascular disease.
  
  
  METHODS
  We investigated the effect of a 6-month quitting smoking programme on aortic stiffness, central pressure and wave reflections in chronic heavy smokers. Seventy-one (83% normotensives) long-term heavy smokers [>20 cigarettes/day and exhaled carboxy haemoglobin (COHb) (> or =4% and CO ppm > or =21)] completed a 6-month psychological-based stop-smoking program. Patients were divided into two groups. Thirty-one patients aged 45+/-2 years, 71% male, fully quit smoking for 6 months (COHb <2% and CO ppm <10 at 1, 3 and 6 months)--group I, whereas 40 patients aged 45+/-1 years, 73% male, did not change their smoking habits--group II. We measured between baseline and changes after 6 months in aortic stiffness assessed as pulse wave velocity (Complior), central-peripheral pulse pressure (PP) amplification ratio (PPAr), wave reflection (augmentation index corrected for heart rate), augmentation pressure and transit time (Sphygmocor). Ambulatory 24 h blood pressure (ABP) data were obtained at baseline and after 6 months in 36 patients (n = 19) of group I and 17 of group II.
  
  
  RESULTS
  In group I, but not in group II, there were significant reductions of peripheral systolic BP (baseline: 131+/-4 to after 6 months: 127+/-4 mmHg, P<0.04) and of systolic BP (baseline: 121+/-4 to after 6 months: 114+/-4 mmHg, P<0.03). In group I from baseline to after 6 months, PPAr increased by 13.1+/-4.1% and transit time (ms) by 8.7+/-2.9%; augmentation index was reduced by 9.2+/-1.6%, augmentation pressure by 5.7+/-1.9 mmHg (all P<0.03 vs. baseline and vs. group II); and pulse wave velocity by 2.3+/-2.8% (P = 0.062). In group I, only daytime ABP was reduced from baseline to after 6 months (129/82+/-2/2 to 123/78+/-2/2 mmHg, P<0.03), whereas no change in 24h-ABP was found in group II.
  
  
  CONCLUSIONS
  Six months of smoking cessation is associated with clear improvement of reflected waves, central pressure and aortic stiffness, and with a reduction of daytime BP. This may contribute to the improvement of cardiovascular prognosis attributed to smoking cessation.
authors.affiliation: Unidade Hipertensão e Risco Cardiovascular, Hospital Pedro Hispano, Matosinhos, Faculdade de Medicina do Porto, Faculdade Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal. jjpolonia@mail.telepac.pt
authors.forename: Jorge
authors.initials: J
authors.lastname: Polónia
authors.forename: Loide
authors.initials: L
authors.lastname: Barbosa
authors.forename: José Alberto
authors.initials: JA
authors.lastname: Silva
authors.forename: Manuel
authors.initials: M
authors.lastname: Rosas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001011:Aorta / Q000503:physiopathology*; D001794:Blood Pressure; D004548:Elasticity; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016540:Smoking Cessation; D055815:Young Adult