title: Patterns of water-pipe and cigarette smoking initiation in schoolchildren: Irbid longitudinal smoking study.
abstract: BACKGROUND
  Tobacco use remains a major public health problem worldwide. Water-pipe smoking is spreading rapidly and threatening to undermine the successes achieved in tobacco control.
  
  
  METHODS
  A school-based longitudinal study in the city of Irbid, Jordan, was performed from 2008 to 2010. All seventh-grade students in 19 randomly selected schools, out of a total of 60 schools in the city, were enrolled at baseline and surveyed annually.
  
  
  RESULTS
  Of the 1781 students enrolled at baseline 1,701 (95.5%) were still in the study at the end of the second year of follow-up (869 boys, median age at baseline 13 years). Ever and current water-pipe smoking were higher than those of cigarette smoking at baseline (ever smoking: 25.9% vs. 17.6% and current smoking: 13.3% vs. 5.3% for water-pipe and cigarette smoking, respectively; p < .01 for both) but cigarette smoking caught up by the second year of follow-up (ever smoking: 46.4% vs. 44.7%; p = .32 and current smoking: 18.9% vs. 14.9%; p < .01). Water pipe-only smokers at baseline were twice as likely to become current cigarette smokers after 2 years compared with never smokers (relative risk (RR) = 2.1; 95% CI = 1.2, 3.4). A similar pattern was observed for cigarette-only smokers at baseline (RR = 2.0; 95% CI = 0.9, 4.8).
  
  
  CONCLUSIONS
  Prevalence of water-pipe and cigarette smoking increased dramatically over the 2-year follow-up period with similar patterns in boys and girls, although girls had lower prevalence in all categories. Water-pipe smoking at baseline predicted the progress to cigarette smoking in the future and vice versa.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, University of Memphis, 3820 DeSoto Avenue, Browning Hall 114, Memphis, TN 38152, USA. fmzayek@memphis.edu
authors.forename: Fawaz
authors.initials: F
authors.lastname: Mzayek
authors.forename: Yousef
authors.initials: Y
authors.lastname: Khader
authors.forename: Thomas
authors.initials: T
authors.lastname: Eissenberg
authors.forename: Radwan
authors.initials: R
authors.lastname: Al Ali
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Ward
authors.forename: Wasim
authors.initials: W
authors.lastname: Maziak
mesh_terms: D000293:Adolescent; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007597:Jordan / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D015995:Prevalence; D012574:Schools; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology* / Q000639:trends; D011795:Surveys and Questionnaires; D014867:Water
chemical_list: D014867:Water