Drug and Alcohol Dependence 169 (2016) 64–67
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Daily nicotine patch wear time predicts smoking abstinence in socioeconomically disadvantaged adults: An analysis of ecological momentary assessment data Ping Ma a,∗ , Darla E. Kendzor b , Insiya B. Poonawalla c , David S. Balis d , Michael S. Businelle b a
Children’s Health/Children’s Medical Center at Dallas, Dallas, TX, United States University of Oklahoma Health Sciences Center, Oklahoma Tobacco Research Center, Oklahoma, OK, United States c Department of Health Promotion and Behavioral Sciences, Dallas, TX, United States d University of Texas Southwestern Medical Center, Department of General Internal Medicine, Dallas, TX, United States b
a r t i c l e
i n f o
Article history: Received 8 July 2016 Received in revised form 12 September 2016 Accepted 10 October 2016 Available online 18 October 2016 Keywords: Smoking Smoking cessation Nicotine patch Low socioeconomic status Ecological momentary assessment African American
a b s t r a c t Introduction: Individuals who use the nicotine patch are more likely to quit smoking than those who receive placebo or no medication. However, studies have not yet examined the association between actual daily nicotine patch wear time during the early phase of a smoking cessation attempt and later smoking abstinence. The purpose of this study was to address this gap in the literature. Methods: Participants who enrolled in a safety-net hospital smoking cessation program were followed for 13 weeks (i.e., 1 week pre-quit through 12 weeks post-quit). Participants completed in-person assessments and daily ecological momentary assessments on study provided smartphones. Multivariate logistic regressions were used to determine if daily patch wear time during the first week post-quit predicted 7day biochemically verified point prevalence smoking abstinence 4 and 12 weeks following the scheduled quit date. Demographic characteristics and smoking behaviors were adjusted as covariates. Results: Participants (N = 74) were primarily non-White (78.7%) and most (86%) had an annual household income of <$20,000. Greater average hours of daily nicotine patch wear time during the first week post-quit was associated with a greater likelihood of abstinence at the 4 and 12 week post-quit visits (aOR = 2.22, 95% CI:1.17-4.23; aOR = 2.24, 95% CI:1.00-5.03). Furthermore, more days of wearing the patch for ≥19 h was associated with a greater likelihood of abstinence at the 4 and 12 week post-quit visits (aOR = 1.81, 95% CI:1.01-3.22; aOR = 2.18, 95% CI:1.03-4.63). Conclusions: Greater adherence to the nicotine patch early in a quit attempt may increase the likelihood of smoking cessation among socioeconomically disadvantaged adults. © 2016 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Although the prevalence of smoking has declined to 16.8% among adults in the United States, 30.4% of those living at or below the poverty threshold continued to smoke in 2014 (Jamal et al., 2015). Socioeconomically disadvantaged adults are less likely to quit smoking and to sustain long-term abstinence (Businelle et al., 2010; Fernandez et al., 2006; Kendzor et al., 2010; Siahpush and Carlin, 2006), despite having similar numbers of quit attempts compared with smokers of higher socioeconomic status (SES; Kotz and West, 2009). Recently, public health efforts have begun to focus on
∗ Corresponding author at: Children’s Health/Children’s Medical Center at Dallas, 2777 N. Stemmons Freeway, Dallas, TX, 75207, United States. E-mail address:
[email protected] (P. Ma). http://dx.doi.org/10.1016/j.drugalcdep.2016.10.013 0376-8716/© 2016 Elsevier Ireland Ltd. All rights reserved.
these disparities; including offering pharmacotherapy (e.g., Nicotine Replacement Therapy (NRT), varenicline, bupropion) at low or no cost to help low income adults to quit smoking (Cutrona et al., 2005; Kofman et al., 2012; Miller and Sedivy, 2009). The nicotine patch is the most commonly used NRT (Fiore et al., 2008b). With a once daily application, the patch provides a consistent level of nicotine, and medication compliance rates may be greater than other forms of NRT (Shiffman et al., 2000). Clinical trials have demonstrated that the nicotine patch reduces craving and withdrawal symptoms and increases the likelihood of longterm abstinence compared with placebo (Ahluwalia et al., 1998; Cummings et al., 1997; Fiore et al., 1994; Fiscella and Franks, 1996). Furthermore, the 24-h nicotine patch reduces withdrawal symptoms and has superior cessation outcomes compared with the 16-h patch (Aubin et al., 2006; Fiore et al., 2008a; Shiffman et al., 2000).
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The first week following a quit attempt is key to cessation success (Ashare et al., 2013; Cofta-Woerpel et al., 2011; Garvey et al., 1992). Cravings, negative mood, and other withdrawal symptoms often peak during the initial days of a quit attempt, making relapse common during this period (Businelle et al., 2010; Cofta-Woerpel et al., 2011; Garvey et al., 1992; Hendricks et al., 2006; Hughes, 1992, 2007; Kahler et al., 2002; Piper et al., 2008). Thus, consistent use of smoking cessation pharmacotherapy is especially important during this period (Ashare et al., 2013; Ferguson et al., 2009; Piper et al., 2008; Shiffman et al., 2008b). To date, little is known about the relation between daily nicotine patch wear time and the likelihood of achieving smoking abstinence. Evaluating the association between nicotine patch wear time during the early post-quit period and subsequent smoking status may provide useful information about the optimal use of the patch during a quit attempt. Ecological momentary assessments (EMA) utilize handheld devices to collect data in near real-time in real-life situations (Businelle et al., 2014; Hammersley, 1994; Shiffman et al., 2008a). EMA is recognized as a means to reduce recall bias and errors in memory (Shiffman et al., 2008a). Although this approach has been commonly used in studies that examine substance use (i.e., smoking, alcohol consumption, drug use; Ferguson and Shiffman, 2011; Shiffman, 2009) and a variety of other health behaviors (i.e., physical activity, eating behaviors; Garcia-Palacios et al., 2014; Garcia et al., 2014; Marszalek et al., 2014), utilization of EMA techniques to examine the association between medication adherence and smoking cessation is understudied. Thus, the purpose of the current study was to use an EMA approach to measure daily nicotine patch wear time during the first week of a scheduled quit attempt, and to evaluate the association between patch wear time and biochemically-verified smoking abstinence at 4 and 12 weeks post-quit. Based upon previous research, it was also hypothesized that the number of days where the patch was worn for at least 80% of the day (e.g., ≥19 h per day for 24 h patch; Catz et al., 2011; Hays et al., 2010; van Boven and Vemer, 2015) would increase the likelihood of abstinence at 4 and 12 weeks post-quit. 2. Methods 2.1. Participants Study participants were recruited to participate in a randomized controlled trial of a smoking cessation intervention during their orientation visit to the Tobacco Cessation Clinic at the Dallas County safety-net hospital between August 2011 and April 2013 (for a description of the parent study see Kendzor et al., 2015). Individuals were eligible to participate if they: 1) demonstrated > 6th grade English literacy level, 2) were willing to quit smoking 7 days from their first visit, 3) were ≥ 18 years of age, 4) had an expired carbon monoxide (CO) level ≥ 8 ppm, 5) were smoking ≥ 5 cigarettes per day, and 6) were able to attend all scheduled study visits. 2.2. Study design and procedures Of 222 participants that were screened for the parent study, 146 were eligible and enrolled. All participants were seen individually by a physician at the baseline visit to discuss/prescribe medication (e.g., nicotine patch, varenicline, bupropion) and at subsequent visits to follow-up on progress with smoking cessation. At the baseline visit, participants completed socio-demographic and smoking history questionnaires on study computers via Questionnaire Development System (QDS) software (NOVA Research, Bethesda, MD). Additionally, all participants received and were instructed on how to use a study provided LG Optimus smart-phone to complete three types of daily ecological momentary assessments (EMA) during their pre-quit (1 week) and post-quit weeks (1 week):
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phone-initiated daily diary and random assessments, and selfinitiated event sampling assessments (e.g., pre-cessation smoking, post-quit urge, post-cessation lapse). A more detailed description of our EMA procedures is reported elsewhere (Businelle et al., 2014). The sample used in the present study was limited to those who were prescribed the nicotine patch (n = 74); while participants who received other types of pharmacotherapy or no medication (n = 72) were excluded. The first 19 participants in the parent study were not given the opportunity to be assessed at 12 weeks post-quit. Thus, the total sample size for those who were prescribed the patch who could attend the 12 week follow-up assessment was 68 participants. At the baseline visit, all participants were prescribed a standard 21 mg/24 h or 14 mg/24 h nicotine patch according to their level of smoking. Data from 480 daily diary assessments (92.7% of all assigned daily diary assessments were completed; M = 6.5 assessments per participant) completed during the first week of the scheduled quit attempt were used in the current analyses. 2.3. Measures 2.3.1. Demographic and smoking characteristics. Demographic and smoking characteristics were assessed at baseline including age, race (White vs. Black or other racial/ethnic minority), sex (male vs. female), treatment group (Usual Care vs. Contingency Management), education level ( < high school vs. ≥high school), years of smoking, and average cigarettes smoked per day. Note that race was dichotomized because the sample was predominantly Black or White, with few participants of other racial/ethnic backgrounds. 2.3.2. Nicotine patch wear time. Participants responded to a series of questions about their prescribed smoking cessation medication on the daily diary assessment each morning. Participants who were prescribed the nicotine patch and confirmed “taking their medication yesterday” were subsequently asked “how many hours did you wear the nicotine patch yesterday” (1 = did not wear it at all, 2 = less than 3 h, 3 = 4–6 h, 4 = 7–9 h, 5 = 10–12 h, 6 = 13–15 h, 7 = 16–18 h, 8 = 19–21 h, 9 = 22–24 h). The middle time point for the selected time category was used to indicate the period of daily patch wear time (i.e., 1 = 0 h, 2 = 2 h, 3 = 5 h, 4 = 8 h, 5 = 11 h, 6 = 14 h, 7 = 17 h, 8 = 20 h, 9 = 23 h). Thus, nicotine patch wear time was recoded to create a continuous variable. Each participant’s average daily nicotine patch wear time was then computed by averaging wear time across the 7 day post-quit period. In addition, considering findings from previous studies that have indicated that 80% or greater adherence to smoking cessation medications is associated with better abstinence outcomes, (Catz et al., 2011; Hays et al., 2010; van Boven and Vemer, 2015) we calculated the number of days that each participant wore the patch for at least 80% of the day (i.e., 19 h or more) during the first post-quit week. Thus, average hours of daily patch wear time and number of days of wearing the patch for at least 80% of the day were separately examined as predictors. 2.3.3. Smoking status. Seven-day point prevalence abstinence at 4 weeks and 12 weeks post-quit were the outcome variables. Abstinence was defined as self-reported, and biochemically verified expired carbon monoxide (CO) levels of < 8 ppm. Participants with missing CO data were considered non-abstinent. 2.4. Statistical analysis Participant characteristics were summarized with means and standard deviations for continuous variables and percentages for categorical variables. Multivariate logistic regression analyses were conducted to determine if average nicotine patch wear time during the first post-quit week predicted biochemically-verified abstinence at the 4 and 12 week follow-up visits. We also examined if the number of days where the patch was worn for 80% or more of
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Table 1 Demographic and smoking characteristics at baseline (N = 74). Characteristics
% or Mean (SD)
Age (years) Gender (% Female) Race White Black Others Education (% ≥ high school) Married or living with significant other (% yes) Annual household income (% < $20,000) Smoking variables Cigarettes per day Years of smoking
50.9 (6.5) 59.5 27.0 66.2 6.8 67.6 29.7 86.2 16.7 (8.7) 30.6 (8.4)
the day (e.g., ≥19 h per day) was associated with an increased likelihood of abstinence at 4 weeks and 12 weeks post-quit. All analyses adjusted for race, gender, age, years of education, treatment group assignment (parent study), and pre-quit cigarettes smoked per day. Analyses were conducted using STATA 13.0 (STATA Corp., College Station, TX). 3. Results The 74 participants who were prescribed the nicotine patch were included in this study. The majority of the sample was American African (66.2%) with most household incomes lower than $20,000 per year (86.0%). The participants smoked 16.7 cigarettes per day on average (Range: 5 to 40). Participant characteristics are presented in Table 1. Overall 35.1% of all participants achieved 7day biochemically-verified point prevalence abstinence at the 1 week post-quit visit, 33.8% were met abstinence criteria at the 4 week visit and 19.4% met abstinence criteria at the 12 week postquit visit. Participants reported wearing the nicotine patch for an average of 13.6 h/day (SD = 9.2) during the first post-quit week and wore the patch for ≥ 19 h on 3.07 days (SD = 2.85). Logistic regression analyses controlling for race, gender, age, years of education, treatment group, and pre-quit cigarettes smoked per day indicated that more hours of nicotine patch wear time during the first week post-quit was positively associated with greater likelihood of achieving smoking abstinence at the 4 week (aOR = 2.22, 95% CI: 1.17-4.23) and 12 week (aOR = 2.24, 95% CI: 1.00-5.03) post-quit visits. Thus, a one standard deviation increase in hours of daily patch wear time corresponded to a 122% or 124% increase in the likelihood of achieving smoking abstinence at 4 and 12 weeks post-quit visit, respectively. In addition, more days of wearing the nicotine patch for at least 19 h (i.e., ≥80% of the recommended hours) was associated with a greater likelihood of achieving smoking abstinence at the 4 (aOR = 1.81, 95% CI: 1.013.22) and 12 week (aOR = 2.18, 95% CI: 1.03-4.63) post-quit visits. Thus, a one standard deviation increase in days wearing the patch for >19 h corresponded to an 81% or 118% increase in the likelihood of achieving abstinence at the 4 and 12 weeks post quit visit respectively. Treatment group was significantly associated with smoking abstinence at 4 and 12 week post-quit visits (ps < 0.05), but no significant association was found between other covariates and abstinence status. Fig. 1A and B illustrate the relationships between average daily nicotine patch wear time and number of days of ≥19 h of patch wear time during the first post-quit week and confirmed abstinence at the 4 and 12 week post-quit follow-up visits. 4. Discussion This is the first study to use EMAs to show that average daily patch wear time during the first week of a scheduled quit attempt predicts smoking abstinence at 4 and 12 weeks post-quit, after controlling for covariates. Findings also indicated that more days
Fig. 1. (a) Relationship between average hours of daily patch wear time during the first week post-quit and confirmed abstinence and 12 weeks post-quit. Note: Values on the x-axis are a cumulative. For example, abstinence data for participants who wore the patch for 23 h are represented in each category on the x-axis. (b) Relationship between number of days of ≥19 h of daily patch wear time and confirmed abstinence at 4 at 4 and 12 weeks post-quit. Note: Values on the x-axis are a cumulative. For example, abstinence data for participants who wore the patch for 7 days are represented in each category on the x-axis.
of wearing the patch for at least 80% of the day was associated with greater abstinence. Study findings highlight the importance of compliance with nicotine patch prescription guidelines in socioeconomically disadvantaged smokers making a smoking cessation attempt. Importantly, greater duration of patch wear time predicted later abstinence. Findings suggest that prescribers should redouble their efforts to monitor and ensure that the patch is being worn all day during the early phase of a quit attempt to increase the likelihood of achieving abstinence. Study limitations include a small sample that was recruited from one safety-net hospital in Dallas, which may limit generalizability of findings. In addition, daily assessments of patch wear times were available for only the first post-quit week. Future studies should examine the relation-
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ship between daily patch wear time and later smoking abstinence in larger samples and over longer time periods. Funding This work was supported by funding from the University of Texas, School of Public Health (to D. E. Kendzor and M. S. Businelle). Manuscript preparation was additionally supported by American Cancer Society grants MRSGT-10-104-01-CPHPS (to D. E. Kendzor) and MRSGT-12-114-01-CPPB (to M. S. Businelle). Contributors Authors PM and MSB conceptualized the study. MSB and DEK designed and conducted the parent study. PM and IBP conducted literature searches and reviews. PM conducted statistical analysis and wrote the first draft of the manuscript. MSB, IBP, DEK and DB modified the draft manuscripts. All authors have approved the final manuscript. Conflict of interest All authors declared no conflicts of interest. Acknowledgements This work was supported, in part, by the Duncan Family Institute for Cancer Prevention and Risk Assessment and the National Institutes of Health Support Grant CA016672 through the MD Anderson Cancer Center. Drs. Businelle and Kendzor were located at the University of Texas School of Public Health in Dallas, Texas during the data collection period for this study. References Ahluwalia, J.S., McNagny, S.E., Clark, W.S., 1998. Smoking cessation among inner-city African Americans using the nicotine transdermal patch. J. Gen. Int. Med. 13, 1–8. Ashare, R.L., Wileyto, E.P., Perkins, K.A., Schnoll, R.A., 2013. The first 7 days of a quit attempt predicts relapse: validation of a measure for screening medications for nicotine dependence. J. Addict. Med. 7, 249–254. Aubin, H.J., Luthringer, R., Demazieres, A., Dupont, C., Lagrue, G., 2006. Comparison of the effects of a 24-hour nicotine patch and a 16-hour nicotine patch on smoking urges and sleep. Nicotine Tob. Res. 8, 193–201. Businelle, M.S., Kendzor, D.E., Reitzel, L.R., Costello, T.J., Cofta-Woerpel, L., Li, Y., Mazas, C.A., Vidrine, J.I., Cinciripini, P.M., Greisinger, A.J., Wetter, D.W., 2010. Mechanisms linking socioeconomic status to smoking cessation: a structural equation modeling approach. Health Psychol. 29, 262–273. Businelle, M.S., Ma, P., Kendzor, D.E., Reitzel, L.R., Chen, M., Lam, C.Y., Bernstein, I., Wetter, D.W., 2014. Predicting quit attempts among homeless smokers seeking cessation treatment: an ecological momentary assessment study. Nicotine Tob. Res. 16, 1371–1378. Catz, S.L., Jack, L.M., McClure, J.B., Javitz, H.S., Deprey, M., Zbikowski, S.M., McAfee, T., Richards, J., Swan, G.E., 2011. Adherence to varenicline in the COMPASS smoking cessation intervention trial. Nicotine Tob. Res. 13, 361–368. Cofta-Woerpel, L., McClure, J.B., Li, Y., Urbauer, D., Cinciripini, P.M., Wetter, D.W., 2011. Early cessation success or failure among women attempting to quit smoking: trajectories and volatility of urge and negative mood during the first postcessation week. J. Abnorm. Psychol. 120, 596–606. Cummings, K.M., Hyland, A., Ockene, J.K., Hymowitz, N., Manley, M., 1997. Use of the nicotine skin patch by smokers in 20 communities in the United States, 1992–1993. Tob. Control 6 (Suppl. (2)), S63–70. Cutrona, C.E., Russell, D.W., Brown, P.A., Clark, L.A., Hessling, R.M., Gardner, K.A., 2005. Neighborhood context, personality, and stressful life events as predictors of depression among African American women. J. Abnorm. Psychol. 114, 3–15. Ferguson, S.G., Shiffman, S., 2011. Using the methods of ecological momentary assessment in substance dependence research?smoking cessation as a case study. Subst. Use Misuse 46, 87–95. Ferguson, S.G., Gitchell, J.G., Shiffman, S., Sembower, M.A., 2009. Prediction of abstinence at 10 weeks based on smoking status at 2 weeks during a quit attempt: secondary analysis of two parallel, 10-week, randomized, double-blind, placebo-controlled clinical trials of 21-mg nicotine patch in adult smokers. Clin. Ther. 31, 1957–1965.
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