title: [Effect of tobacco smoking on leptin serum levels and its relationship with steroid hormones and bone mineral density].
abstract: OBJECTIVE
  Leptin is an hormone resulting from the obesity gene. Their actions could be important in the pathogenesis of the osteoporosis. The aim of this study is to analyse the influence of tobacco on serum leptin levels, and its relationship with bone mineral density (BMD) and steroid hormones.
  
  
  METHODS
  A group of healthy volunteers were recruited and classified as smokers or non-smokers. A subgroup of smokers ceased smoking during one month. Serum leptin and steroids hormones levels were analysed, and a baseline BMD was measured. In the abstinent group the analysis was repeated at the end of the study.
  
  
  RESULTS
  Fifty-nine healthy volunteers were included (22 of which were smokers). Fifteen smokers remained abstinent for a month. Both groups were similar except in age, being smokers older. Male smokers had lower lumbar BMD (p = 0.017). After adjusting by age, serum leptin levels were higher in smokers than in non-smokers, with statistical differences in women (p = 0.049). Abstinence increased leptin levels, though not reaching statistical significance. An inverse correlation between leptin levels and androstendione in men (r = -0.622; p = 0.001), and a positive correlation with testosterone in women (r = 0.405; p = 0.019) were found. After adjusting by body mass index, only the correlation of leptin levels with androstendione persisted.
  
  
  CONCLUSIONS
  Leptin negatively correlate with sex hormones in young men and is influenced by smoking in young women. Thus, the hormone could be relevant for bone mass regulation in smoker persons.
authors.affiliation: Servicio de Medicina Interna y Enfermedades Infecciosas, URFOA-IMIM, Hospital del Mar, Universitat Autònoma de Barcelona, Barcelona, España. asupervia@imas.imim.es
authors.forename: August
authors.initials: A
authors.lastname: Supervía
authors.forename: Anna
authors.initials: A
authors.lastname: Enjuanes
authors.forename: Joan
authors.initials: J
authors.lastname: Vila
authors.forename: Leonardo
authors.initials: L
authors.lastname: Mellibovsky
authors.forename: Xavier
authors.initials: X
authors.lastname: Nogués
authors.forename: Adolfo
authors.initials: A
authors.lastname: Díez-Pérez
mesh_terms: D000328:Adult; D015519:Bone Density; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D012907:Smoking / Q000097:blood / Q000503:physiopathology*
chemical_list: D012739:Gonadal Steroid Hormones; D020738:Leptin