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. Author manuscript; available in PMC: 2016 Aug 1.
Published in final edited form as: Drug Alcohol Depend. 2015 Jun 6;153:167–172. doi: 10.1016/j.drugalcdep.2015.05.038

Predictors of adherence to pharmacological and behavioral treatment in a cessation trial among smokers in Aleppo, Syria

Ziyad Ben Taleb a,*, Kenneth D Ward b,c, Taghrid Asfar c,d, Raed Bahelah a,e, Wasim Maziak a,c
PMCID: PMC4509913  NIHMSID: NIHMS697922  PMID: 26077603

Abstract

Introduction

The development of evidence-based smoking cessation programs is in its infancy in developing countries, which continue to bear the main brunt of the tobacco epidemic. Adherence to treatment recommendations is an important determinant of the success of smoking cessation programs, but little is known about factors influencing adherence to either pharmacological or behavioral treatment in developing countries settings. Our study represents the first attempt to examine the predictors of adherence to cessation treatment in a low-income developing country.

Methods

Predictors of adherence to pharmacological and behavioral treatment were identified by analyzing data from a multi-site, two-group, parallel-arm, double-blind, randomized, placebo-controlled smoking cessation trial in primary care clinics in Aleppo, Syria. Participants received 3 in-person behavioral counseling sessions plus 5 brief follow-up phone counseling sessions, and were randomized to either 6 weeks of nicotine or placebo patch.

Results

Of the 269 participants, 68% adhered to pharmacological treatment, while 70% adhered to behavioral counseling. In logistic regression modeling, lower adherence to pharmacological and behavioral treatment was associated with higher daily smoking at baseline, greater withdrawal symptoms, and perception of receiving placebo instead of active nicotine patch. Women showed lower adherence than men to behavioral treatment, while being assigned to placebo condition and baseline waterpipe use were associated with lower adherence to pharmacological treatment.

Conclusion

Adherence to cessation treatment for cigarette smokers in low-income countries such as Syria may benefit from integrated cessation components that provide intensive treatment for subjects with higher nicotine dependence, and address concurrent waterpipe use at all stages.

Keywords: smoking, cessation, adherence, cigarettes, developing countries

1. Introduction

Tobacco smoking remains the leading cause of preventable deaths world-wide. Currently, tobacco is responsible for an estimated 6 million deaths every year (Erikson et al, 2013). This annual death toll is expected to increase to 10 million within the next 20–30 years, with 80% of these deaths occurring in developing countries (WHO, 2013a). These trends call for comprehensive approaches for tobacco control, especially in low-income countries, which continue to bear most of the brunt of the tobacco epidemic (World Bank, 2010).

Promoting smoking cessation is a cornerstone in the fight to reduce tobacco related morbidity and mortality (WHO, 2013a). This is why one of the main articles of the Framework Convention on Tobacco Control (FCTC) requires governments to take effective measures to promote cessation of tobacco use and adequate treatment for tobacco dependence (WHO, 2010). At least in developed countries, the application of a mixture of behavioral and pharmacological cessation interventions has been shown to help a proportion of smokers to quit smoking (Fiore et al., 2008). Unfortunately, in developing countries, where most of the world's smokers reside (Jha et al., 2006), the infrastructure for smoking cessation is lacking and little work is being done to develop effective cessation interventions that take into account local smoking patterns, health care resources and culture (Maziak et al., 2004). For example, in Syria, a Middle Eastern country with a high prevalence of cigarettes and waterpipe smoking (WHO, 2013b; Ward et al., 2006), there are no clinical practice standards, specialty cessation clinics or pharmacological agents available to assist smokers to quit (Asfar et al., 2008, 2011; Maziak et al., 2004; Ward et al, 2013).

To date, there is only one randomized clinical trial of a behavioral/pharmacological smoking cessation intervention that was conducted in a developing country setting (Ward et al., 2013). Results from this trial showed that combined pharmacological and behavioral treatment induced cessation in 12% of participants at one year post-reatment. This study, along with a bulk of evidence from developed countries, highlighted the importance of adherence to treatment (e.g., attendance at counseling sessions, taking medication as instructed) in predicting successful cessation outcomes; Shiffman et al., 2008; Alterman, 1999). As such, factors contributing to better adherence to cessation treatment have received substantial attention in order to guide the development of approaches that improve adherence to cessation interventions (Alterman et al., 1999; Berg et al., 2013; Cooper et al., 2004; Patterson et al., 2003). However, little if any evidence currently exists to assist in fostering adherence to cessation treatments in developing countries. The current study aims to address this knowledge gap by identifying potential predictors of adherence to pharmacological and behavioral treatment in a developing country's health care setting (Syria).

2. Methods

2.1 Study design

This study utilized data from a multi-site two-group, parallel-arm, double-blind, randomized, placebo-controlled trial conducted in primary care clinics in Aleppo, Syria from 2007 to 2008. Full details of the trial and methods are published elsewhere (Ward et al., 2013). Eligible and interested smokers were randomized to receive either behavioral cessation counseling + active transdermal nicotine patches (TN) or behavioral cessation counseling + placebo TN. A total of 269 smokers were recruited, 18-65 years old, who had smoked > 5 cigarettes/day for at least one year. Participants were patients who resided within the catchment area of one of the four primary health care clinics included in the study. Each clinic had a primary care physician who served as a cessation coordinator, liaised between other physicians and clinic-staff to ensure adherence to the study protocol, and delivered the intervention to participants.

2.2 Pharmacological Intervention

Patients in the active treatment group received a six-week supply of Nicotinell™ patches, 24-h dose, using a step-down algorithm. Patients in the placebo group received the same step-down algorithm. Placebo patches were provided by a local manufacturer.

2.3 Behavioral counseling

All patients received behavioral cessation counseling using approaches shown to be effective in developed countries (Abrams and Niaura, 2003; Fiore et al., 2008) and adapted for the local culture based on previous research (Asfar et al., 2008). Three individual, in-person sessions (approximately 30 min each) and 5 brief (approximately 10 min) phone calls, were delivered by the cessation coordinator.

2.4 Procedures

Participants provided baseline demographic data, smoking related information (e.g., smoking history, level of dependence, previous quit attempts, readiness to quit smoking), and completed additional questionnaires to assess quitting self-efficacy, stage of change, withdrawal symptoms, perceived social support, and depression/mood. Participants then were assigned to one of two treatment conditions [Arm A (n=134): behavioral counseling + active TN vs. Arm B (n=135): behavioral counseling + placebo TN] using random permuted blocks, stratified by clinic and gender.

2.5 Measures

2.5.1 Baseline predictors

Socio-demographic variables included age, gender, marital status, number of people in the house, years of education and religion. Smoking-related variables included number of years as a cigarette smoker; current amount smoked (cigarettes/day); previous successful quit attempts defined as quitting smoking for at least 24 hours in the past six months; the Readiness To Quit Ladder (Biener and Abrams, 1991); a single item, Likert-type scale assessing confidence in one's ability to quit; the three subscales of the Smoking Self-Efficacy/Temptations Questionnaire (Long Form)—Positive Affect/Social Situations, Negative Affect Situations, and Habitual/Craving Situations (Velicer et al., 1990); the Fagerström Test for Nicotine Dependence (FTND; Heatherton et al., 1991); waterpipe use status and tobacco withdrawal symptomatology using the Minnesota Nicotine Withdrawal Scale (MNWS; Hughes and Hatsukami, 1986). We calculated the mean of eight scale items to obtain a total withdrawal score. Other variables included: perceived social support (Zimet et al., 1988, 1990), and depressive symptomatology using the Center for Epidemiologic Studies Depression Scale (CES-D; Radloff, 1977; Thomas et al., 2001). To assess blindness during treatment, patients indicated whether they believed they had received nicotine or placebo patch.

Participants were queried weekly for the duration of the treatment (six weeks) on whether they had followed treatment instructions to use one patch every day over the past week. Based on the literature (Kopjar et al., 2003; Nachega et al., 2006; Ruddy and Partridge, 2009, Berg et al., 2013), we defined being adherent to patch use as responding “yes” to this question during at least 5 of the 6 weeks (>80%). Accordingly, adherence to patch was set up as a dichotomous variable (non-adherent=0, adherent=1).

2.5.2 Adherence to behavioral counseling

Following previous work (Asfar et al., 2008; Klesges et al., 1988; Mizes et al., 1998; Patterson et al., 2003), adherence to behavioral counseling was set as a dichotomous variable (non-adherent=0, adherent=1) indicating whether the subjects completed all vs. some sessions. Specifically, the variable distinguished participants who completed all three in-person sessions + five phone calls from those who missed at least one session or a phone call.

2.6 Statistical Analysis

Baseline characteristics (socio-demographic, smoking and psychosocial characteristics) were compared according to adherence to pharmacological and behavioral treatment for all subjects using the chi-square test for categorized variables and t-tests or Mann– Whitney U tests where appropriate for continuous variables. Bivariate correlations for all predictor variables revealed no multicollinearity. This was also inspected by checking for extraordinary estimated coefficients and standard errors, which would have suggested the existence of collinearity. The outcomes of interest were adherence to patch use and adherence to behavioral counseling. Separate logistic regression models were developed for each outcome variable. All predictors (socio-demographic, smoking-related, and psychosocial variables) significant at the < 0.20 level in bivariate analyses were entered into the models using backward stepwise entry, with only those variables contributing at the < 0.05 level being allowed to remain in the model. The Wald statistic was used to assess the contribution of each predictor to the overall model. Adjusted odd ratios and 95 % Confidence intervals were calculated and reported. All analyses controlled for age and sex. Data were analyzed using SPSS version 21 (SPSS Inc., Chicago, IL, USA).

3. Results

3.1 Characteristics of the sample

Males comprised 78 % of the sample. The mean age was 39.9 years (SD=11.4), with a mean of 10.2 years of education (SD=4.0). The mean number of cigarettes smoked per day was 27.7 (SD= 12.7), while the mean age for the onset of daily smoking was 18.6 years (SD=5.3) and the mean Fagerström nicotine dependence score was 5.7 (SD=2.2). The two treatment groups (nicotine vs. placebo) did not differ significantly on any of these variables at baseline.

Out of the 269 study participants, 183 (68%) were adherent to patch use and 187 (70%) were adherent to behavioral counseling sessions. To assess blindness during treatment, patients indicated whether they believed they had received nicotine or placebo patch, in which 62% of participants on nicotine patch guessed their assignment correctly as compared to only 40% of participants on placebo patch (P <0.001).

3.2 Bivariate associations

Table 1 summarizes the bivariate analysis for baseline characteristics by adherence to patch and behavioral counseling.

Table 1. Baseline characteristics by adherence to pharmacological and behavioral counseling in a cessation trial among smokers in Aleppo, Syria.

80% Adherence to pharmacological treatment Adherence to behavioral counseling
Adherent (n =183) mean (SD) or % Non Adherent (n =86) mean (SD) or % p-value* Adherent (n =187) mean (SD) or % Non Adherent (n =82) mean (SD) or % p-value*
Demographics
age 40.8(11.1) 38.2(11.7) 0.084 41.0(11.2) 37.6(11.4) 0.024
Gender (male %) 77.6 80.2 0.751 80.4 73.2 0.185
Education (years completed) 10.3(4) 10(4) 0.648 10.3(3.8) 10.2(4.6) 0.938
Number of people in the house 5.4(2.9) 5(2.2) 0.333 5.3(2.8) 5.4(2.6) 0.830
Marital status (Married %) 80.9 75.6 0.452 82.6 72 0.245
Religion (Muslim %) 72.7 79.1 0.381 73.9 76.8 0.596
Tobacco use
Treatment group (Nicotine %) 56.3 23.1 0.002 53.8 41.5 0.063
Amount smoked (cigarettes/day) 26(11.7) 31.4(14.1) 0.001 26(11.4) 31.3(14.3) 0.002
Age when smoked first cigarette 19(5.3) 17.7(5.2) 0.049 18.8(5.3) 18.3(5.2) 0.526
Readiness to quit scorea 7.9(0.9) 7.6(1.1) 0.033 7.9(0.9) 7.6(0.9) 0.027
Fagerstrom Test of Nicotine Dependenceb 5.5(2.2) 6.1(2.2) 0.041 5.5(2.2) 6.1(2) 0.060
Confidence in ability to quitc 6.9 (2.4) 6.9 (2.5) 0.950 6.9(2.2) 6.8(2.6) 0.698
Carbon monoxide (p.p.m.) 27.4(17.1) 27.8(13.9) 0.822 28(17.1) 26.2(13) 0.404
Tobacco withdrawal symptoms score 27.3 32.4 0.036 27.2 32.9 0.022
Water pipe use (%) 7.1 18.6 0.005 9.2 14.6 0.192
Perception of treatment (placebo %) 30.1 62.3 <0.001 30.4 61.8 <0.001
Psychosocial
Social supportd 20.7(11.8) 18.9(11.4) 0.240 20.1(11.7) 19.6(11.5) 0.950
Depressions (CES-D) scoree 17.6(10.5) 18.8(9.1) 0.358 17.5(10.1) 19.4(10.2) 0.145
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*

For continuous predictors, a two-sample t-test or Mann–Whitney U test when appropriate evaluated differences in means. For dichotomous predictors, a chi-square test evaluated differences in proportions.

a

Range of possible values for readiness to quit is 0–10.

b

Range of possible values for the Fagerstrom Test of Nicotine Dependence is 0–10.

C

Range of possible values for confidence in ability to quit is 0–10.

d

Range of possible values for the social support score is 0–60.

e

Range of possible values for CES-D score is 0–60

3.2.1 Adherence to patch use

Lower adherence was associated with greater number of cigarettes smoked per day at baseline (P = 0.001), higher FTND score (P=.041), waterpipe smoking (P=.005), self-perception of being allocated to placebo group (P= <.001), greater total withdrawal symptoms (P=.036), being on placebo treatment (P = 0.002), and lower readiness to quit score (P=.033).

3.2.2 Adherence to behavioral counseling (In-person + phone contact)

Lower adherence to behavioral treatment was associated with greater number of cigarettes smoked per day at baseline (P=.002), self-perception of being allocated to placebo group (P= <.001), greater total withdrawal symptoms (P=.022) lower readiness to quite score (P=.027), and younger age (P=.024).

3.3 Regression modelling

For the adjusted model predicting adherence to pharmacologic treatment (Table. 2), participants who received nicotine patch (OR=2.5; 95% CI = 1.3-4.7), perceived themselves as being on nicotine patch (OR=4.3; 95% CI = 2.2-9.3), and who did not use waterpipe (OR=4.2; 95% CI =1.6-11.1), were more likely to adhere to patch usage. Participants who smoked a greater number of cigarettes per day at baseline (OR=0.97; 95% CI =0.94-0.99) and had higher withdrawal symptoms (OR=0.97; 95% CI= 0.95-0.98) were less likely to adhere to patch usage. The adjusted model predicting adherence to behavioral counseling (Table. 2) shows that male participants (OR=2.4; 95% CI=1.2-4.9) and those who perceived themselves as being on nicotine patch (OR=4.6; 95% CI =2.4-8.8) were more likely to adhere to counseling. On the other hand, participant who smoked a greater number of cigarettes per day at baseline (OR=0.97; 95% CI =0.94-0.98) and who had higher withdrawal score (OR=0.98; 95% CI =0.96-0.99) were less likely to adhere to counseling.

Table 2. Predictors of adherence to pharmacologic treatment and behavioral counseling in a cessation trial among smokers in Aleppo, Syria determined by logistic regression.

Adherence to pharmacologic treatment OR CI (95%) P-value
Treatment group
 Nicotine 2.52 1.37−4.78 0.003
 Placebo Ref
Water-pipe use
 Non-smoker 4.25 1.61−11.1 0.004
 Smoker Ref
Total withdrawal symptoms score 0.97 0.95−0.98 0.003
Cigarettes per day 0.97 0.94−0.99 0.014
Perception of treatment allocation
 Nicotine 4.31 2.29−9.31 <0.001
 Placebo Ref
Adherence to behavioral counseling OR CI (95%) P-value
Gender
 Male 2.41 1.21−4.94 0.017
 Female Ref
Total withdrawal symptoms score 0.98 0.96−0.99 0.015
Cigarettes per day 0.97 0.94−0.98 0.021
Perception of treatment allocation
 Nicotine 4.61 2.41−8.84 <0.001
 Placebo Ref
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Note. CI = confidence interval; OR = odds ratio.

For both study outcomes, we examined several interaction terms, including treatment group with baseline withdrawal score, number of cigarettes smoked per day, and perception of treatment allocation (i.e., belief that one had received nicotine and not placebo). We also examined the interaction between gender and baseline withdrawal score. All interaction terms yielded non-significant results (all P-values were > 0.27).

4. Discussion

This is the first study to examine predictors of adherence to smoking cessation treatment in a developing country's health care context. Our findings indicate that lower adherence to pharmacological and behavioral treatments was associated with heavier smoking rate at baseline, greater withdrawal symptomatology, and participants' belief they were receiving placebo instead of active nicotine patch. Women showed lower adherence than men to behavioral treatment, while being assigned to the placebo condition and baseline waterpipe use were associated with lower adherence to pharmacologic treatment. Our findings suggest that adherence to cessation treatment for cigarette smokers in low-income countries such as Syria may benefit from integrated cessation components that provide intensive treatment for subjects with higher nicotine dependence, and address concurrent waterpipe use at all stages. Such novel insights on factors that influence adherence to cessation treatment in a developing country's setting, can help improve cessation treatments for smokers living in countries at similar level of development.

Adherence rates to pharmacological and behavioral treatment achieved in this study appears comparable to studies that have been done in developed countries. For example, the adherence rate to pharmacological treatment in our study (68%) was in agreement with a previous study that examined adherence to medication among adult smokers in two smoking cessation trials in the US (Hays et al., 2010). Moreover, adherence rate to behavioral counseling sessions of 70% achieved in our study also appears comparable with rates achieved in a cessation trial that evaluated adherence to seven sessions of behavioral counseling among adult smokers in the US. (Patterson et al., 2003). This shows that high adherence rates can be achieved in developing country settings when applying standardized procedures and protocols to follow-up with study's participants.

Overall, our study indicates the importance of nicotine dependence as a barrier to adherence to pharmacological and behavioral cessation treatments. Greater tobacco use at baseline and more severe tobacco withdrawal symptomatology both indicate greater dependence, and were associated with lower adherence in our study. A higher FTND score also was associated with lower adherence in bivariate level (P= .041), although such association was outside the significant level in the multivariable models. While nicotine dependence appears to make adherence difficult, it is encouraging that in the current study, the assignment to active nicotine, compared to placebo, was associated with a more than two folds greater odds of being adherent to pharmacologic treatment. This indicates that nicotine replacement therapy can enhance adherence to treatment in highly dependent smokers.

One of the unique findings of this study that is likely to be relevant to most countries in the Middle East, is the association between lower adherence to pharmacological treatment and concurrent waterpipe use. Waterpipe is a common form of tobacco use in the Middle East that delivers substantial amounts of nicotine and is associated with nicotine dependence (Aboaziza and Eissenberg; Maziak, 2014). Furthermore, studies that looked into concurrent use of tobacco products has shown that dual smokers have the highest prevalence of nicotine dependence in contrast to exclusive users (Post et al., 2010; Timberlake, 2008; Tomar et al. 2010). While such evidence is indicative of a potential role of nicotine dependence in mediating the association between waterpipe smoking and lower adherence, this cannot be asserted based on this finding alone. This association however, suggests that cessation efforts in societies, where cigarettes are not the only main tobacco use method, should devote special attention to cultural-specific smoking behaviors (Maziak et al, 2004, Asfar et al, 2008). Previous studies from the same population, show that cigarette smokers can revert to waterpipe smoking during quit attempts, which can facilitate relapse (Hammal et al, 2008; Asfar et al, 2008). As a result, asking about waterpipe smoking and emphasizing cessation of all tobacco use can be instrumental to cessation success.

Interestingly, our data shows that women were less adherent to behavioral counseling than men. This might be attributed to social barriers and gender roles (Maziak, 2006) that might prevent women from freeing themselves from their home duties in order to commit to behavioral counseling. Factors such as transportation, child care and other household responsibilities may have played a role in lowering women's adherence to behavioral counseling. On the other hand, adherence to pharmacologic treatment did not differ by gender, which understandably does not require attendance and can be done at home.

Beliefs and expectations about nicotine patch's effectiveness has been shown to affect adherence beyond whether an active nicotine or a placebo patch is received (Darredeau and Barrett, 2010). In our study, adherence to pharmacologic and behavioral treatment was greater among those who believed that they had received nicotine compared with those who believed they had received placebo, regardless of the actual patch assignment. So believing that one may have received a nicotine patch even if it was in fact a placebo may have increased compliance or encouraged adherence to cessation treatment in general. This suggests that, psychological factors may play an important role in participants' subjective responses to treatment assignment, the effects of which cannot be solely attributed to the direct pharmacological effects of nicotine.

Our study comes with limitations. First, a relatively small sample size may not have allowed us to detect differences that were clinically meaningful but not statistically significant. Thus, we discussed marginally significant findings that might warrant future investigation. Secondly, adherence to patch use was based on self-report. Nevertheless, self-report of adherence to treatment has been widely used in the literature for both smoking cessation treatment and other medications in general (Alterman, et al., 1999; Cooper et al., 2004; Hollands et al., 2013; Okuyemi et al., 2010; Stein et al., 2006).

These limitations notwithstanding, this study provides the first evidence about factors influencing adherence to cessation treatments in a low income country setting in the Middle East. It suggests that adherence to cessation treatment for cigarette smokers in low-income countries such as Syria may benefit from integrated cessation components that provide intensive treatment for subjects with higher nicotine dependence, and address concurrent waterpipe use at all stages.

Highlights.

  • First study to examine predictors of adherence to smoking cessation treatment in a developing country's health care context

  • lower adherence to pharmacological and behavioral treatments was associated with higher daily smoking rate, greater withdrawal symptoms, and participants' belief of being assigned to placebo instead of active nicotine patch

  • Waterpipe use was associated with lower adherence to pharmacologic treatment

  • Offering intensive treatment for smokers with higher nicotine dependence may improve adherence to cessation treatment in low-income countries such as Syria

Acknowledgments

We thank Dr. Kristopher Fennie at Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL, USA, for his thoughtful review and comment on the manuscript

Role of Funding Source: This work was supported by PHS grant 1R01DA024876 (W. Maziak, PI)

Footnotes

Contributors: Ziyad Ben Taleb: Dr. Ben Taleb conceptualized and designed the study, drafted and revised the manuscript, guided and interpreted the analysis, approved the final manuscript as submitted, and agrees to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Kenneth D Ward: Dr. Ward contributed to the acquisition and interpretation of the data, critically revised the article for important intellectual content, approved the final manuscript as submitted, and agrees to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Taghrid Asfar: Dr. Asfar contributed to the acquisition and interpretation of the data, critically revised the article for important intellectual content, approved the final manuscript as submitted, and agrees to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Raed Bahelah: Dr. Bahelah contributed to analysis of data, critically revised the article for important intellectual content, approved the final manuscript as submitted, and agrees to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Wasim Maziak: Dr. Maziak contributed to the acquisition and interpretation of the data, critically revised the article for important intellectual content, approved the final manuscript as submitted, and agrees to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Conflict of interest: The authors of this article declare that they have no conflict of interest

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