title: Cigarette smoking and nephrolitiasis in adult individuals.
abstract: BACKGROUND
  Nephrolithiasis is a widespread multifactorial disorder. Constitutional, environmental and genetic factors play a role in stone formation. Although important advances have been made in understanding the pathophysiology of stone formation, none of the many theories have given a satisfactory explanation of this process.
  
  
  OBJECTIVE
  The objective of study was to evaluate the probable relationship between cigarette smoking and nephrolitiasis in adult men.
  
  
  METHODS
  A total of 102 cases diagnosed with nepholithiasis and 121 age-matched healthy controls were recruited from June 2010 to September 2011. Smoking status and resultant data was obtained from both groups.
  
  
  RESULTS
  Twenty seven (26.5%) of the patients with stones and eighteen (14.9%) of the control group were current cigarette smokers. Our findings showed that smoking significantly increases the risk of nepholithiasis (OR = 2.06, 95% CI: 1.06-4.01, P = 0.034). There was no significant difference in the number of cigarettes smoked (P = 0.830) and years of smoking (P = 0.536) between subjects with and without stones (P = 0.536).
  
  
  CONCLUSIONS
  This study suggests that cigarette smoking might be an independent risk factor for the development of nephrolithiasis.
authors.affiliation: Department of Internal Medicine, Fatemieh Hospital, Semnan University of Medical Sciences, Semnan, IR Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Tamadon
authors.forename: Mohammad
authors.initials: M
authors.lastname: Nassaji
authors.forename: Raheb
authors.initials: R
authors.lastname: Ghorbani
keywords: Adult; Nephrolithiasis; Risk factors; Smoking