title: Longitudinal evaluation of the effect of smoking initiation on body weight, blood pressure, and blood biochemistry.
abstract: OBJECTIVE
  To evaluate the effect of smoking initiation on annual changes in body weight, blood pressure, and blood biochemistry.
  
  
  METHODS
  This study analyzed the results of annual health examinations from 1991 to 2005 in male Japanese workers. Subjects who started smoking (n=214) initially responded as non-smokers in a self-administered questionnaire (baseline year) and then answered consistently as smokers for 3 subsequent years. Out of 2547 non-smokers, we selected 1589 controls who had data available for at least four successive years. The time course of physiological and laboratory data was analyzed using a linear mixed model.
  
  
  RESULTS
  A significant temporal decrease from baseline in body mass index (first year, -0.1 kg/m(2)), diastolic blood pressure (second year, -1.5 mm Hg) and gamma-glutamyl transpeptidase (second year, -3.5 IU/L) was observed for subjects who started smoking. An opposite pattern was observed in non-smokers. On average, those who started smoking had significantly lower body mass index (first year, -0.2 kg/m(2); second year, -0.2 kg/m(2)), systolic blood pressure (second year, -2.1 mm Hg), diastolic blood pressure (second year, -2.0 mm Hg), and gamma-glutamyl transpeptidase (second year, -4.5 IU/L) than non-smokers.
  
  
  CONCLUSIONS
  In this study, smoking initiation did not yield clinically significant long-term benefits with respect to physiological or biochemical outcomes. These results are important because few studies have tracked these types of changes longitudinally from initiation through 3 years of follow-up.
authors.affiliation: Department of Occupational and Environmental Medicine (A2), Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuoku, Chiba, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kadonaga
authors.forename: Mirei
authors.initials: M
authors.lastname: Dochi
authors.forename: Kouichi
authors.initials: K
authors.lastname: Sakata
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Oishi
authors.forename: Kumihiko
authors.initials: K
authors.lastname: Tanaka
authors.forename: Hideki
authors.initials: H
authors.lastname: Morimoto
authors.forename: Etsuko
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Suwazono