INTRODUCTION

Tobacco smoking is one of the leading causes of death amongst the world population. Currently, smoking is related to approximately 20% of total adult mortality in 63 countries overall¹. Smoking prevalence in Russia, where about 60% of men and 21% of women smoke², is one of the highest in the world. Thus, tobacco smoking leads to great damage in the National Health Service. Smoking is estimated to cause more than 17% of all deaths in Russia³. Other studies by Russian authors⁴ showed that 43% of deaths from cancer tumors in men, age 35-69 years, and 89% of all deaths from lung cancer, were attributable to smoking. At the same time, while in most of the developed countries smoking prevalence for the last 20-30 years has considerably decreased, in Russia there has been little change. The reason is the lack of effective anti-smoking measures and programs. Only by the end of 2013 the Federal law ‘About Protection of Health of the Population against Tobacco Consumption Consequences’ was adopted, which provides for the implementation of a complex of educational, administrative, economic and medical anti-smoking measures⁵.

It should be noted that tobacco-control laws and programs work effectively only when a whole package of measures is implemented⁶. It is not productive to give priority to some measures to the detriment of others. The majority of regular smokers suffer from tobacco addiction (TA), which is a serious obstacle to smoking cessation (SC) for patients who would like to stop smoking. Therefore, one of the main directions of the tobacco-control program is development and implementation of qualified and effective forms of SC counselling (SCC) through the health-care system.

Development of effective methods of SC should be conducted with an objective assessment of their efficiency. Tobacco addiction is a chronic disorder that has a high potential for relapse. Therefore, the majority of tobacco users who stop smoking for a short period (several days, weeks and even a month) often relapse⁷. Hence the main condition for objective assessment of efficiency of any SC method or assistance, is a long follow-up period after cessation needed to obtain the objectives of SC.

Furthermore, it is quite important for the development of SCC to identify the factors that have significant influence on the results of SC. Considering such factors as predictors or determinants of SC outcomes may help to provide a more rational and effective SCC.

The main aim of this study was to investigate and evaluate the effectiveness and determinants of successful smoking-cessation methods.

METHODS

RESULTS

Data on age and sex structure of 524 patients included in the study, and data on SCC results, are presented in Table 1. The age varied between 18 and 75 years. The percent of patients aged up to 30 years was 17.6%, from 30 to 49 years was 43.9%, and aged 50 years and more was 38,5%. The percent of men and women in the study cohort were 60% and 40%, respectively.

The analysis of the data of the SCC results in the cohort study (Table 1) shows that out of the total number of the smokers (n=524) who received SCC, 15% of men and 16% of women had not even attempted to change their smoking behaviour afterwards. Special interviews of these patients showed that the main reasons for the lack of attempt to stop smoking after the SCC were: postponement of the attempt to a future time, disbelief in the efficiency of the offered methods of SC, a change of the decision to stop smoking (data not shown).

The majority of smokers 443 (84.5%) made quit attempts after SCC with different outcomes. The percentage of patients with no result after the quit attempt in the age group < 30 years old, for both genders, was significantly less than in the age group 50 years or more; 14.1% and 24.3%, respectively (p <0.05). Most smokers (342, 65.3%) achieved some positive results, while 100 (19,1%) patients succeeded to cut down the number of smoked cigarettes per day by half or more. The number of patients who stopped smoking completely for periods: less than a month, 1-6 months and more than 6 months, were 42 (8%), 76 (14.5%) and 124 (23.7%), respectively. The percentage of men who achieved more than 1-month abstinence was higher than the corresponding percentage of women, 41.7% and 33.8%, respectively, p=0.05. It should be noted that amongst men up to 30 years old 43.6% stopped smoking for more than a month, and for men 50 years old or more 31.2%, p>0.05.

The assessment of the SCC results association with the duration of regular smoking in years (Table 2) shows that in comparison with patients with minimal duration of smoking (1-9 years), the probability to achieve a positive result of SCC was three times more for patients with 10-19 years duration of smoking, OR 3.12 (95% CI 1.58-6.15), and two times more for patients with 20-29 years duration of smoking, OR 1.97 (95% CI 0.97-3.97).

Data on assessment of association of SCC results with the intensity of smoking measured by the number of the cigarettes smoked per day (Table 2) show that the probability of a positive result of SCC decreased in the group of patients who smoked more than 10 cigarettes per day as compared to the group of patients who smoked no more than 10 cigarettes per day, OR 0.59 (CI 0.33-1.03).

The assessment of the SCC results association with the TA degree estimated by the Fagerström test shows that the probability to achieve a positive result for patients with TA Fagerström-test score 5 or more was almost significantly less, OR 0.66 (95% CI 0.41-1.06), than that for patients with a score of 1-4 points (Table 2).

Data on the assessment of the association of SCC results with existence and outcome of previous quit attempts in the patients’ smoking history show that the existence of a previous quit attempt increases the probability for a positive result in the last quit attempt. In particular, the probability to achieve a positive result of SCC was 3.71 times higher (95%CI: CI 1.70-8.12) for patients who had quit for some period in a previous attempt, in comparison with those who had no results in the previous quit attempt.

The probability of an SCC positive result rises significantly with increasing level of personal motivation and readiness to stop smoking, measured in points by the special questionnaire test. In particular, the probability to achieve a positive result of SCC was 4.3 times higher for patients with 15 or more points for the level of motivation to stop smoking than that of patients with less than 11 points, OR=4.3; 95% CI 1.85-10.00 (Table 2).

In the analysis of the association of SCC results with smokers’ adherence to SCC recommendations and medication, the relevant data were used only concerning 443 patients, as 81 patients, not having made any attempts to stop smoking, were excluded from this analysis. All patients who made attempts to stop smoking after SCC were divided into 4 groups: 1) patients who did not carry out any recommended methods on SC and tried to stop smoking only by willpower, 2) patients who used only cognitive-behavioral approaches, 3) patients who used only prescribed medicine, and 4) patients who used both cognitive-behavioral approaches and prescribed medicine. Data regarding SCC results for these 4 groups are presented in the Table 3. In the group of patients who did not carry out any recommended methods of SC only 28.5% succeeded to stop smoking for 1 month or more, in the group using only cognitive-behavioral recommendations 40.2%, and in the group using only prescribed medicine 43.4%, while in the group of patients who used both cognitive-behavioral recommendations and prescribed medicine it was 54.1% (p< 0.001).

DISCUSSION

The majority of regular smokers should be considered as patients with an addictive disease and need professional counselling and assistance to quit tobacco use. This study analyzed the SC success rate among patients who had received professional SCC in Moscow.

There are many studies that have provided the evaluation of different methods of SC aid and assistance. However, a disadvantage in most such studies is the short-term follow-up of the patient after SC assistance, and hence a correspondingly short-term success rate of SC, which is used as a criterion for efficiency of any SC aid. Many smokers manage to stop smoking for a short term, a few days to weeks. At the same time TA is very disposed to a relapse and the vast majority of patients who stopped smoking for such terms return to regular smoking^{7, 9}. Therefore, SC for such short periods cannot be considered as effective treatment of TA. More evidential and objective criteria of SC aid effectiveness are SC terms of 3, 6 and 12 months¹⁰. This study was conducted to investigate the efficacy of qualified SCC and the factors associated with its success when the final follow-up review was made no less than 6 months afterwards.

For objective assessment of the efficacy of any kind of SC aid all variants of possible results should be considered, from the absence of any result to a successful complete SC for a long term. Out of 524 smokers included in the study, about 15% did not even attempt to stop smoking after receiving SCC. The more typical causes of refusal to try and stop smoking were a low level of motivation and readiness to practical performance of SC, a ‘contemplation’ stage of smoking-behavior change¹¹. Such smokers visited SC services often out of curiosity rather than because of a serious intention to quit smoking. Of the patients, 19% who had received SCC tried to stop smoking but without any results.

Within our study, most of the patients who had received SCC did achieve some results. In particular, 19% of smokers cut down the number of cigarettes per day by more than half. This outcome should be taken into consideration as an SCC result, since such significantly reduced smoking intensity reassures these smokers of their ability to control smoking behavior and to keep a low intensity of smoking indefinitely or even quit smoking in the future¹². More than 46% of smokers completely stopped smoking for different terms, including 24% who stopped smoking for 6 months or more. These results agree with the results of similar studies given in the literature^{13, 11, 15}. According to the results of the NHS Stop Smoking Service in England, at the 4-week follow-up after SC assistance 50% of people successfully quit¹⁴, and at the 6-month follow-up after the quit date 23% of patients did not start smoking¹⁶. SC assistance conducted with hospitalized patients, as usual, has a higher success rate^{14, 17, 18}.

It is known that many different factors and characteristics may be determinants of smoking behavior and cessation¹⁹. This study has identified several factors that can have a significant influence on SC results. The percentage of all men who quit smoking for more than a month was notably higher than the corresponding percentage of women. Though, in the studied cohort of smokers this difference does not reach statistical significance. These data are consistent with those of other studies that show a lower efficiency of TA treatment for women in comparison with men²⁰. In particular, it was indicated in the report of the NHS Stop Smoking Service in England that the percentage of successful quit smoking attempts in all age groups was higher amongst men than in women¹⁴. However, another study found convincing evidence that men in general are not more successful in smoking cessation than women²¹.

The present study also revealed that the percentage of men and women, who successfully quit, at 1 month or more follow-up, was higher in the younger group of patients (<30 years) compared to the senior age group (> 49 years). The association of SC results with the age has already been noted in other studies and sometimes with different evaluations^{19, 23}. It should be noted that such an association of SC result with age, as in this study may be possible only amongst patients motivated to stop smoking and who visit SC services. Thus, younger smokers with less TA more often successfully quit in comparison with senior smokers who have longer duration of regular smoking and a greater degree of TA.

The assessment of the association between the degree of TA measured by a Fagerström test and the result of the SCC shows that in subgroups of smokers the percentage of patients who successfully quit notably decreases with increasing TA degree. The significance of TA degree for efficiency of TA treatment has been already repeatedly specified in earlier literature. Moreover, some authors consider nicotine dependence as a major factor in predicting long-term cessation^{7,12, 22, 23}.

The role of smoking cessation history is also significant as a determinant of SCC outcome. Results of this study show that existence of previous attempts to quit smoking, in personal smoking history, increases the probability of SC success. The better the result of a previous attempt to quit; the more effective the latest attempt. Thus, patients who in the past could significantly reduce the number of cigarettes smoked or could stop smoking for different terms achieved smoking cessation much more often in comparison with those who had an unsuccessful previous attempt. The dependence of the result of the last quit attempt on the existence of an earlier attempt to quit has been indicated in earlier studies²⁴. It was found that the efficiency of the next attempt increased if the previous attempt was rather recent, no more than a year ago, and some success had been achieved^{12, 25, 24}. But the likelihood of achieving sustained abstinence was reduced for smokers with a failed quit attempt within the last year²⁵. Hence, it follows that a relatively recent successful quit attempt can increase motivation to stop smoking and to repeat the quit attempt. It is known that many former smokers finally quit after two or more attempts²³.

This study confirms also that patients who followed all SCC recommendations achieved better results compared to the patients who did not follow any recommendations. Thus, the adherence to professional recommendations for SC should be considered as a significant determinant of the SC result²⁶.

This study revealed that the association of the SCC outcome with the level of motivation and readiness for SC, measured by a special questionnaire test⁸, was the strongest one. In the subgroup of smokers with the highest level of motivation to quit, the probability of successful SC was 4 times more than in the subgroup of patients with the minimum level of motivation. These data reinforce the assertion that motivation and willingness to quit is the most significant determinant and predictor of smoking cessation^{15, 18}. The level of motivation to quit should be considered as a fundamental factor and predictor for the success of any kind of SC aid. The level of motivation to quit can determine the SCC result association with other factors, such as age, experience of SC, adherence to SCC recommendations and TA treatment^{15, 28}. It is known that the level of motivation to quit in the population of smokers can significantly differ^{10, 11}. The majority of smokers understand that tobacco smoking is harmful to their health and it is better to quit, but at the same time many of them have doubts and questions like: ‘To which degree is it harmful to me? Will I be able to live without smoking, which gives me a certain «comfort» in life? Can I overcome my TA?’. Many smokers who in the past have already tried to quit without any success have doubts about their ability to quit. Smokers with a small intensity of smoking (less than 10 cigarettes per day) are often convinced that their smoking is harmless, and therefore it is not necessary to quit^{27, 29}. All these smokers need a qualified consultation to remove doubts and questions concerning their smoking and motivation to quit.

CONCLUSIONS

Most regular smokers need special aid for SC. Such qualified aid must include three main components: provide knowledge about tobacco intoxication, tobacco addiction, and consequences; provide personal motivation to quit smoking; and recommend therapy for TA, including behavioral technics, medicine and other methods. This qualified aid can increase the probability of a successful SC by three and more times^{12, 30}. At the same time, the need for various components of the aid and their extent, can significantly differ between smoking individuals, depending on personal smoking characteristics and determinants of SC effectiveness. Therefore, a special examination of smoking history and status, degree of TA, knowledge about harmful consequences of smoking, existence and stage of motivation to quit smoking, must precede the SC aid. Based on the data obtained, the character and extent of the individualized SC aid is determined¹⁰. Consideration of individual peculiarities of smoking behavior, and the main determinants of the SC results, can significantly increase efficiency of professional SC aid and make it more rational.

We identified that the outcome of SC aid is determined mainly by the balance of two main independent determinants; level of motivation and TA degree. All other factors like age, sex, personal characteristics, form and methods of the aid, are secondary or minor. Furthermore, the main determinants have larger value for the SC assistance effectiveness than form and methods of this assistance. First of all, the level of motivation should be necessarily considered at an evidence-based tobacco cessation service. It will make this kind of medical aid more personalized and effective.