The aim of the present study was to analyze the changes in the characteristics of Spanish smokers who received a psychological treatment for smoking cessation and the changes in the effectiveness of that treatment, between the years 2001 and 2010. This period was important, as it was when the Spanish government passed two relevant legislative measures in relation to the control of smoking.
The results reveal substantial differences between the smokers seeking treatment for giving up smoking at the Smoking Cessation Unit in the University of Santiago de Compostela (Spain) over a 10-year period (2001–2010). Those smokers who sought treatment in the period 2006–2010 were older, had been smoking for longer, smoked fewer cigarettes and of brands with lower nicotine and tar content, were less motivated to give up smoking, and had more depressive antecedents than those who applied for the same treatment in the period 2001 to 2005. The decrease in the number of cigarettes smoked daily in people who sought treatment is in line with the fall reported by Nebot and Fernández
 in Spanish smokers. This decrease may be due, as suggested by Warner
 and Yong, Borland, Thrasher and Thompson
, to an increase of the social pressure (e.g., rise in the price of cigarettes, specific legislation for controlling consumption in certain spaces, etc.). It is not surprising that the number of cigarettes smoked per day has decreased if we take into account that it is forbidden to smoke in locations where it was permitted previously, such as the workplace or bars. As Villalbí points out
, some indicators, as a decrease in tobacco sell figures, have been a clear reflection of the reduction of tobacco use in the Spanish population. However, although the number of cigarettes smoked appears to have declined, the decrease in the percentage of smokers is not that significant, which can also be due to the economical crises or to the increase of other types of tobacco, as can be roll-your-own cigarettes, that has also been indicated by previous studies
On the other hand, the reduction in the level of motivation does not agree with what was proposed by Hughes
, who points out that in the United States the remaining smokers are more motivated to give up smoking due to the growth of anti-smoking campaigns. According to a previous study conducted in Galicia, Spain
, only 19% of the smokers were on the preparation stage, regardless of age or gender, and 44% of the total daily smokers had made some serious attempts to quit smoking. In contrast, the percentage of smokers of the clinical population in the preparation stage, despite having decreased in these ten years, they were significantly older. The lower motivation on seeking treatment found among the 2006–2010 group may be related to lower self-efficacy as regards the ability to give up smoking in a relatively short period of time (30 days). This low self-efficacy could, in turn, be related to the increased numbers of smokers with depressive problems in this period. According to previous studies
, smokers with antecedents of depression would be highly motivated to give up smoking, but with low self-efficacy for achieving that goal. Thus, the fact that many of the smokers who come to treatment state that their intention to give up smoking is more in the medium term (6 months) than the short term (30 days) may be due to their low perceived self-efficacy, rather than to lower motivation to change. Therefore, it would be necessary to take into account both the different stages of the motivational process in which the smoker is situated at the time of the intervention
 and his or her perceived self-efficacy.
As regards nicotine dependence, we found no differences between the two groups. Despite the prevalence of daily smokers in the general Spanish population has decreased (31.7% in 2001 and 23.9% in 2012), we have not found an increase in the level of nicotine dependence among those who continue smoking and seek treatment. This goes against the results reported in previous studies carried out in other countries
[12, 13, 16]. So this does not confirm the “hardening hypothesis” among smokers seeking treatment. Recent studies conducted in smokers of the general population in Spain
 or Italy
 did not found support for this hypothesis either.
About the evolution of the effectiveness of the treatment for giving up smoking, the percentage of abstinence has decreased by more than 5%. Previous research in countries like the United States had already indicated such a trend
. In our case, the increased incidence of depression in the period 2006–2010 may explain the reduced effectiveness of the treatment in that period. As Piper et al.
 and Schroeder and Morris
 found, the presence of depression reduces the likelihood of success when a person tries to give up smoking. On the other hand, we cannot support the argument of de Leon et al.
, since in our study the increase in psychopathological problems is not related to a rise in nicotine dependence that could explain the poorer treatment outcomes. Our results are in line with the view that smokers with moderate dependence have more problems for giving up smoking
In relation to the variables that predict abstinence at the end of the treatment and in the follow-ups, we also found substantial differences. Whilst in the 2001–2005 group having antecedents of depression, a high rate of cigarettes smoked per day and low motivation for change predict lower likelihood of abstinence in any period, in the 2006–2010 group not having experienced a depressive episode is associated only with giving up smoking at the end of the treatment, and not with abstinence at the follow-ups. In this group, initial cigarette consumption is the most important variable for predicting abstinence. Therefore, having or not having depression is not anymore an important variable for predicting the success of smoking cessation treatment, at least in the long term. Perhaps due to the high percentage of smokers with this problem in the 2006–2010 group, depression has lost its predictive value, so that number of cigarettes smoked becomes the variable with the greatest weight for explaining the results in the follow-ups. Given the notable increase in numbers of smokers with depressive antecedents who wish to give up smoking, we might suggest, in line with Borrelli’s
 proposal, the need to adapt smoking cessation treatment for this type of smoker, modifying aspects such as the mechanisms necessary for bringing about change, the way of intervention or the intensity of the programme, with the goal of improving treatment effectiveness.
Thus, the results obtained over these 10 years indicate that, in Spain, there has been a qualitative change in the profile of the smoker seeking psychological smoking cessation treatment (fewer cigarettes smoked, less motivation for change, and greater presence of depressive antecedents), but we have not found changes in nicotine dependence. Moreover, the effectiveness of smoking cessation treatment has decreased and there has been a significant change in the variables that predict intervention outcomes.
The present study has several limitations. First of all, the results obtained cannot be extrapolated to smokers in the general population, as smokers who seek specialized treatment for giving up the habit tend to be qualitatively different from those who do not
[39, 40]. Moreover, those studies that have reviewed the evolution of smokers’ characteristics have revealed different outcomes, as regards nicotine dependence, for example, according to whether the smokers in question are from the general population or clinical population
. Secondly, it might be advisable to assess the evolution of smokers’ dependence with other instruments, such as the NDSS-S (Nicotine Dependence Syndrome Scale-Short)
 or the DSM criteria. Finally, we only took into account psychopathological antecedents related to depression. Various studies have stressed the need to take account of other types of disorder, such as anxiety disorders, mainly because of their high prevalence
To summarize, over the last decade we have seen a significant fall in the prevalence of smokers in the general population. At the same time, however, as found in the present study, there has been a substantial change in the characteristics of smokers who seek specialized treatments for giving up smoking (and not always in the same line as in countries other than Spain) and a decrease in the effectiveness of such treatments. We consider it necessary to continue making progress toward improving interventions designed to address the serious health problem of smoking, adapting ourselves to the new profiles and demands of the population.