Materials and methods: In this study, 608 patients (397 male and 211 female) admitted to a smoking cessation clinic to quit smoking between 1 January 2006 and 1 June 2010 were investigated. Routine biochemical and hematological tests, pulmonary function tests, exhaled carbon monoxide levels, electrocardiographs, and chest X-rays were obtained from all of the patients. Th e questionnaire forms, ...