title: Quitting smoking may restore hematological characteristics within five years.
abstract: OBJECTIVE
  To describe the cross-sectional association of counts of total and subtypes of leukocytes, platelets, and selected characteristics of red blood cells with intensity of cigarette smoking and smoking cessation.
  
  
  METHODS
  The study population consisted of 16,254 men and women 20-70 years of age who participated in the Dutch European Prospective Investigation into Cancer and nutrition (EPIC) subcohort, 1995-1997. Linear regression analysis was performed, for both sexes separately, to study the relation between various measurements of smoking habits and hematologic characteristics.
  
  
  RESULTS
  Among current smokers, in both genders, packyears and daily number of cigarettes were associated with increased leukocytes (6-19%), lymphocytes (4-14%), monocytes (3-9%), neutrophils (7-24%), platelets (1-5%), mean corpuscular volume (0.4-2%), hematocrit (0.3-4%), hemoglobin (0.3-4%), and mean corpuscular hemoglobin (0.8-2%). In subjects who had quit smoking within two years before blood measurement, hematological characteristics in most cells were similar as in never smokers, whereas normal counts of lymphocytes and monocytes were observed only 2-5 years after quitting.
  
  
  CONCLUSIONS
  Our findings suggest a marked influence of current smoking habits on leukocyte counts and, to a lesser extent, on counts of erythrocytes and platelets. Following smoking cessation, at least five years have to pass before changes in all hematological parameters may return to normal values.
authors.affiliation: Department of Chronic Diseases Epidemiology, National Institute of Public Health and Environment, Bilthoven, The Netherlands.
authors.forename: Elfrieke
authors.initials: E
authors.lastname: Van Tiel
authors.forename: Petra H M
authors.initials: PH
authors.lastname: Peeters
authors.forename: Henriette A
authors.initials: HA
authors.lastname: Smit
authors.forename: Nico J D
authors.initials: NJ
authors.lastname: Nagelkerke
authors.forename: A Jeanne
authors.initials: AJ
authors.lastname: Van Loon
authors.forename: Diederik E
authors.initials: DE
authors.lastname: Grobbee
authors.forename: H Bas
authors.initials: HB
authors.lastname: Bueno-de-Mesquita
mesh_terms: D000328:Adult; D000368:Aged; D001772:Blood Cell Count; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004906:Erythrocyte Count; D005260:Female; D006400:Hematocrit; D006454:Hemoglobins; D006801:Humans; D007958:Leukocyte Count; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010976:Platelet Count; D012737:Sex Factors; D012907:Smoking / Q000097:blood* / Q000503:physiopathology; D016540:Smoking Cessation; D013997:Time Factors
chemical_list: D006454:Hemoglobins