Association between depressive mood and cigarette smoking in a large Italian sample of smokers intending to quit: implications for treatment

Objective: The aim of the study is to assess the prevalence and degree of depression at baseline of a large cohort of smokers intending to quit. Methods: A cross-sectional investigation was carried out on a population of 757 smokers attending the Medical Service for Addictive Disorders, at Verona University Hospital. The degree of nicotine addiction was measured by the Fagerstrom Test of Nicotine Dependence (FTND) and current mood tested by the Self-rating Depression Scale (SDS), a commonly used and well validated instrument to assess depressive mood. Results: Two hundred and twenty-two subjects (30.3%) were depressed at baseline (SDS test score >= 50). Bivariate analysis, using the SDS score dichotomised at the cut-off of 50 as dependent variable, shows that female gender (p=0.01) and widowhood (p<0.001) were correlated to depression. Logistic regression analysis confirms the correlation between depression and female gender (OR=2.03, IC 95%=1.42-2.88, p<0.001) and between depression and widowhood, with the greatest risk of depression among widows and widowers (OR=3.22, IC 95%=1.01-10.27, p<0.048). Conclusions: The study showed a high degree of pre-treatment depression in smokers intending to quit. Although the association between depression and nicotine dependence has been consistently reported many times, and it is well known that depressed subjects find it more difficult to quit, most guidelines seem not to consider this connection. These findings suggest the need for baseline assessment of depression by screening all smokers seeking assistance in quitting, a priority health objective because smoking is the number one avoidable killer in developed countries.