Prevalence of smoking and reasons for continuing to smoke: a population-based study

OBJECTIVE: To investigate the prevalence of smoking and the reasons for continuing to smoke among adults in Brazil. METHODS: This was a cross-sectional, population-based study including 1,054 individuals ≥ 40 years of age, residents of the city of Florianopolis, Brazil, of whom 183 were smokers. All of the smokers completed the University of São Paulo Reasons for Smoking Scale (USP-RSS). Depressive symptoms were evaluated with the Hospital Anxiety and Depression Scale, and spirometry was performed to screen for COPD. RESULTS: Of the 183 smokers, 105 (57.4%) were female, 138 (75.4%) were White, and 125 (63.8%) were in a low economic class. The mean level of education among the smokers was 9.6 ± 6.1 years. The mean smoking history was 29 ± 15 pack-years, 59% of the men having a ≥ 30 pack-year smoking history. Approximately 20% of the smokers had COPD, and 29% had depressive symptoms, which were more common in the women. The USP-RSS scores were highest for the pleasure of smoking (PS), tension reduction (TR), and physical dependence (PD) domains (3.9 ± 1.1, 3.6 ± 1.2, and 3.5 ± 1.3, respectively). Scores for the PS, TR, and weight control (WC) domains were significantly higher in women. Smokers with a > 20 pack-year smoking history scored significantly higher on the PD, PS, automatism, and close association (CA) domains. Smoking history was associated with the PD, PS, TR, and CA domains. Depressive symptoms were associated with the PD, social smoking, and CA domains (p = 0.001; p = 0.01; p = 0.09, respectively). Female gender and a low level of education were associated with the PS domain (p = 0.04) and TR domain (p < 0.001). CONCLUSIONS: The prevalence of smoking in our sample was relatively high (17.4%). The USP-RSS domains PS, TR, and WC explain why individuals continue smoking, as do depressive symptoms.