Prevalence and risk factors of cholelithiasis in Amol city, northern Iran: a population based study.

BACKGROUND Cholelithiasis is one of the most prevalent gastrointestinal disorders requiring hospitalization.  While different factors influence gallstone formation in patients, these factors are not the same in different societies or in different geographical locations. AIM To evaluate the epidemiology and risk factors associated with gallstone formation in a large population group, the present survey was conducted in northern Iran. METHODS In 6143 asymptomatic subjects, the incidence of gallstone formation as well as risk factors were evaluated through a structured questionnaire, physical examination and ultrasonography study. Sample selection was based on stratified cluster systemic randomization. RESULTS Of these enrolled subjects 3507 (57.1%) were male and 2636 (42.9%) were female with a mean age of 42.71 ± 17.1 years.  The prevalence of gallstones was 0.80%.  On multivariate analysis, the risk of gallstone disease is correlated to rural locale, diastolic hypertension, age, and TG levels.  However, systolic hypertension, glucose serum levels and obesity were also significantly associated with the presence of gallstones. CONCLUSION The present study proposes that the rate of gallstone disease in northern Iran is lower than previous studies have reported, and that most of the risk factors can be prevented by changes in lifestyle and diet.