Background: Smoking is a major risk factor for Chronic Obstructive Pulmonary Disease (COPD), but only 15-20% of smokers get diagnosed. Tobacco dependence may affect smoking patterns that increase tobacco exposure and predispose to lung function decline.

Aims: We aimed to assess tobacco dependence among current smokers with and without COPD and evaluate its role in early disease detection.

Methods: We performed a cross-sectional study in Greek rural areas using the Fagerström Test for Nicotine Dependence. Current smokers were classified into COPD and non-COPD group based on spirometry parameters.

Results: Among 362 current smokers, 288 participants comprised the non-COPD and 71 the COPD group. Both groups presented moderate nicotine dependence (6.2±2.7), but smokers with COPD scored higher in the 1st question (time between awakening and 1st cigarette as an addiction gradient) compared to smokers without COPD. Multiple logistic regression analysis revealed higher COPD prevalence in smokers with higher score in the Fagerström test (odds ratio OR=1.12, 95% confidence interval [1.01 ? 1.24]) and older age (OR=1.06 [1.03 ? 1.09]). Among smokers with COPD, multiple linear regression analysis showed that the forced expiratory volume in the 1st second (FEV₁), decreases by 2.3% of predicted value for each point increase in the Fagerström test and 0.58% for each year of age, independently of participants? gender and pack-years smoking index.

Conclusions: The Fagerström test for Nicotine Dependence score appears to indicate higher probability for COPD and lung function decline, when assessed along with age in current smokers. Our findings highlight the importance of structured smoking cessation support.