title: Correlates of nicotine dependence in U.K. resident Yemeni khat chewers: a cross-sectional study.
abstract: BACKGROUND
  Khat chewing is often associated with tobacco use with impacts on health. This cross-sectional study aimed (a) to explore and validate aspects of self-reported tobacco smoking and whether objective measures of tobacco smoking differ in different situations among khat chewers who smoked and (b) to assess the social factors correlated with nicotine dependence among khat chewers who smoked regularly.
  
  
  METHODS
  This study recruited a purposive sample of 204 U.K. resident Yemeni khat chewers during random visits to Khat sale outlets. Data were collected via a face-to-face scheduled interview. Data analyses included descriptive tests and a hierarchical linear multiple regression.
  
  
  RESULTS
  Of 133 self-reported tobacco smokers, 68% were regular smokers with a mean (SD) carbon monoxide (CO) score (20.53 ± 12.12 ppm) and 32% were episodic smokers with a mean (SD) CO score (16 ± 15.66 ppm). Tobacco smoking as an enhancement of the impacts of khat chewing was reported by 65% and 69% of regular and episodic smokers, respectively. In both groups, higher CO scores were recorded during khat chewing. Hierarchical linear multiple regression modeling showed that increases in levels of severity of dependence on khat chewing were correlated positively with increase in levels of nicotine dependence (β = .27, p = .006, 95% CI = 0.05, 0.29), whereas social participation was correlated inversely (β = -.34, p = .001, 95% CI = -0.06, -0.02).
  
  
  CONCLUSIONS
  In this study, smoking prevalence was high. Smoking increased during khat chewing. Nicotine dependence levels correlated positively with khat dependence levels, while higher social participation reduced nicotine dependence.
authors.affiliation: Queen Mary University of London, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK. s.kassim@qmul.ac.uk
authors.forename: Saba
authors.initials: S
authors.lastname: Kassim
authors.forename: Sharif
authors.initials: S
authors.lastname: Islam
authors.forename: Ray E
authors.initials: RE
authors.lastname: Croucher
mesh_terms: D000293:Adolescent; D000328:Adult; D029754:Catha; D003430:Cross-Sectional Studies; D003710:Demography; D005006:Ethnicity; D006801:Humans; D008297:Male; D008409:Mastication; D015995:Prevalence; D012907:Smoking / Q000453:epidemiology; D012919:Social Behavior; D019966:Substance-Related Disorders / Q000453:epidemiology* / Q000208:ethnology; D014029:Tobacco Use Disorder / Q000453:epidemiology* / Q000208:ethnology; D006113:United Kingdom / Q000453:epidemiology; D015006:Yemen / Q000208:ethnology