Assessing nicotine dependence: a comparison of the Fagerström Tolerance Questionnaire (FTQ) with the Fagerström Test for Nicotine Dependence (FTND) in a clinical sample

Suicidality prospectively predicts greater urges to smoke following a cessation attempt: Mediation through perceived barriers to cessation

Growing interest in developing more effective smoking cessation treatments has facilitated the need to further investigate cognitive-affective factors that inhibit successful smoking cessation, such as urges to smoke. Research has strongly supported an association between suicidality and smoking, yet no work has investigated whether suicidality may increase urges to smoke. The current study sought to evaluate the impact of suicidality on smoking-related cognitive-affective factors predictive of smoking relapse among a community sample of 209 daily smokers engaged in a smoking cessation program. Structural equation modeling (SEM) was used to test the effects of self-reported pre-cessation suicidality on urges to smoke 1 month post-cessation as well as whether this effect was mediated by greater barriers to cessation. Results indicated that internal barriers to cessation significantly mediated the effect of pre-cessation suicidality on greater urges to smoke 1 month following smoking cessation attempt. These findings suggest that elevated suicidality may affect perceived internal barriers to cessation and subsequently urges to smoke 1 month following a quit attempt.

The Perception of Female Smokers with Fibromyalgia on the Effects of Smoking on Fibromyalgia Symptoms

OBJECTIVE

Smokers with fibromyalgia have greater pain intensity and function impairment compared to nonsmokers. Patients' perceptions of interactions between smoking and fibromyalgia symptoms have not been described. The primary aim of this study was to report the perceptions of female smokers with fibromyalgia on how smoking affects symptoms.

METHODS

Forty-eight daily smokers with fibromyalgia enrolled in the Mayo Clinic Fibromyalgia Treatment Center completed the Fibromyalgia Impact Questionnaire, Fagerstrom Test for Nicotine Dependence, Patient Health Questionnaire-9, General Anxiety Disorder-7 and a Fibromyalgia Symptoms and Smoking Survey which queried how smoking directly affected fibromyalgia symptoms (eg, pain, tiredness/fatigue, stiffness, nervousness/anxiety, depression/blueness, irritability, concentration, and overall) or indirectly as a coping mechanism.

RESULTS

The majority of subjects reported smoking had no direct effect on fibromyalgia physical symptoms (pain [60% reported no effect], fatigue [56%], stiffness [81%]) but direct improvement of emotional symptoms (anxiety [62% reported improvement], irritability [64%]). The majority of subjects used smoking to cope with pain (69%) via distraction (83%) and relaxation (77%), lessening emotional distress by reducing a sense of frustration (83%) or sadness (54%) because of pain, and as a justification for resting vis-à-vis "smoke breaks" (69%). Thirty-one smokers were mildly and 17 moderately/severely dependent on tobacco, and no difference in fibromyalgia impact score (P = 0.70), pain (P = 0.39), depression (P = 0.20), and anxiety (P = 0.64) scores were detected, but more moderately/severely dependent subjects reported smoking improved pain (50% vs. 17%, P = 0.04).

DISCUSSION

Smokers with fibromyalgia reported smoking helped to cope with fibromyalgia pain but generally did not directly ameliorate fibromyalgia physical symptoms.

Rates and predictors of renewed quitting after relapse during a one-year follow-up among primary care patients

BACKGROUND

Most people who quit smoking relapse within a year of quitting. Little is known about what prompts renewed quitting after relapse or how often this results in abstinence.

PURPOSE

This study seeks to identify rates, efficacy, and predictors of renewed quit attempts after relapse during a 1-year follow-up.

METHODS

Primary care patients in a comparative effectiveness trial of smoking cessation pharmacotherapies reported daily smoking every 6-12 weeks for 12 months to determine relapse, renewed quitting, and 12-month abstinence rates.

RESULTS

Of 894 known relapsers, 291 (33%) renewed quitting for at least 24 h, and 99 (34%) of these were abstinent at follow-up. The average latency to renewed quitting was 106 days and longer latencies predicted greater success. Renewed quitting was more likely for older, male, less dependent smokers, and later abstinence was predicted by fewer depressive symptoms and longer past abstinence.

CONCLUSIONS

Renewed quitting is common and produces meaningful levels of cessation.

Attentional bias in adults with cannabis use disorders

There has been modest examination of attentional bias in individuals with cannabis use disorders. Clinical implications of this work are directly relevant to better informing extant evidence-based treatment for substance use disorders (e.g., relapse prevention) and/or developing novel interventions. The overarching aim of this investigation was to examine a novel attentional bias task in adults with cannabis use disorders. Participants were comprised of 25 adults (8 women: M age = 31, SD = 6.8; range = 22-45) with cannabis use disorders (n = 12) and controls (n = 13) without any current (past month) psychopathology. Relative to controls, adults with cannabis use disorders had greater attentional bias scores. These differences were present only at the 125-ms probe time, where the cannabis use disorders group showed greater attentional bias to cannabis cues than the control group (adjusted p = .001, cannabis use disorders mean = 59.9, control mean = -24.8, Cohen's d-effect size for 125 ms = 1.03). The cannabis use disorders group also reported significantly greater perceived stress and post-task stress scores than the control group, but stress was not related to attentional bias. This study informs understanding of the influence of cannabis cues on visual detection and reaction time under different cue-target onset times, as attentional bias was most prevalent under time pressure to detect the probe.

A combined analysis of worldwide studies demonstrates an association between bipolar disorder and tobacco smoking behaviors in adults

OBJECTIVES

Worldwide studies were combined to examine two hypotheses: (i) bipolar disorder is associated with smoking behaviors, compared with the general population; and (ii) smoking behavior prevalences in bipolar disorder are intermediate between those in major depressive disorder and those in schizophrenia.

METHODS

Combined analyses used 56 articles on adults obtained from a PubMed search or the senior author's article collection. Odds ratios (ORs) and their 95% confidence intervals (CIs) compared current smoking, heavy smoking among current smokers, smoking cessation in ever smokers, and ever smoking in bipolar disorder versus control groups.

RESULTS

The combined OR was 3.5 (CI: 3.39-3.54) in 51 current smoking studies of bipolar disorder versus the general population from 16 countries. More limited data provided an OR = 0.34 (CI: 0.31-0.37) for smoking cessation and an OR = 3.6 (CI: 3.30-3.80) for ever smoking. The combined OR was 0.76 (CI: 0.74-0.79) for current smoking in bipolar disorder versus schizophrenia in 20 studies from ten countries. Ever smoking may be lower in bipolar disorder than in schizophrenia (OR = 0.83, CI: 0.75-0.91). The OR was 2.05 (CI: 2.00-2.10) for current smoking in bipolar disorder versus major depression in 18 studies from seven countries. Ever smoking may be higher (OR = 1.5, CI: 1.40-1.70) and smoking cessation lower (OR = 0.51, CI: 0.45-0.59) in bipolar disorder than in major depression.

CONCLUSIONS

Increased current smoking in bipolar disorder versus the general population reflected increased ever smoking (initiation) and decreased smoking cessation. Smoking behavior frequencies in bipolar disorder may be between those in depressive disorder and schizophrenia, with schizophrenia showing the highest severity level.

Treating substance abuse is not enough: comorbidities in consecutively admitted female prisoners

INTRODUCTION

Several studies have pointed to high rates of substance use disorders among female prisoners. The present study aimed to assess comorbidities of substance use disorders with other mental disorders in female prisoners at admission to a penal justice system.

METHODS

A sample of 150 female prisoners, consecutively admitted to the penal justice system of Berlin, Germany, was interviewed using the Mini-International Neuropsychiatric Interview (MINI). The presence of borderline personality disorder was assessed using the Structured Clinical Interview II for DSM-IV. Prevalence rates and comorbidities were calculated as percentage values and 95% confidence intervals (CIs).

RESULTS

Ninety-three prisoners (62%; 95% CI: 54-70) had substance use disorders; n=49 (33%; 95% CI: 24-42) had alcohol abuse/dependence; n=76 (51%; 95% CI: 43-59) had illicit drug abuse/dependence; and n=53 (35%; 95% CI: 28-44) had opiate use disorders. In the group of inmates with substance use disorders, 84 (90%) had at least one other mental disorder; n=63 (68%) had comorbid affective disorders; n=45 (49%) had borderline or antisocial personality disorders; and n=41 (44%) had comorbid anxiety disorders.

CONCLUSIONS

Female prisoners with addiction have high rates of comorbid mental disorders at admission to the penal justice system, ranging from affective to personality and anxiety disorders. Generic and robust interventions that can address different comorbid mental health problems in a flexible manner may be required to tackle widespread addiction and improve mental health of female prisoners.

Depression and anxiety symptoms moderate the relation between negative reinforcement smoking outcome expectancies and nicotine dependence

OBJECTIVE

Smoking reinforcement expectancies-expectations that smoking modulates mood-can be powerful motivators to smoke, resulting in increased nicotine dependence. The impact of smoking reinforcement expectancies on nicotine dependence may be particularly strong in individuals with increased mood or anxiety symptoms because they may be more likely to act on expectancies with smoking behavior in order to offset their affective symptoms. This study examined levels of emotional symptom dimensions as moderators of the relation between positive and negative smoking reinforcement expectancies and nicotine dependence severity in a community sample.

METHOD

In a cross-sectional design, 317 daily cigarette smokers (215 men) completed self-report measures of smoking reinforcement expectancies, mood and anxiety symptoms, and nicotine dependence.

RESULTS

Increasing levels of negative affect and anxiety symptoms strengthened associations between negative reinforcement smoking expectancies and nicotine dependence severity (moderation effects; (βs > .13; ps < .03) but did not moderate relations between positive reinforcement expectancies and dependence. Anhedonia did not moderate relations involving either positive or negative reinforcement smoking expectancies.

CONCLUSIONS

Distinct components of anxiety and depressive symptoms interact differently with smoking reinforcement expectancies. Emotional symptoms characterized by excesses in aversive (but not deficits in appetitive) functioning may amplify tendencies to compulsively act on negative reinforcement expectancies by smoking. Cessation treatments that target negative reinforcement expectancies may be particularly salient for emotionally distressed smokers.

The Association of Pain With Smoking and Quit Attempts in an Electronic Diary Study of Cancer Patients Trying to Quit

INTRODUCTION

The purpose of this electronic daily diary study was to examine the relation of pain to smoking and quit attempts among 34 cancer patients with pain enrolled in a smoking cessation program.

METHODS

Electronic daily diary assessments of pain and smoking were collected at the end of each day for a 2-week period during smoking cessation treatment. Pain experienced throughout the day was measured on a scale from 1 to 5, from "no pain" to "pain as bad as you can imagine." Smoking was defined as the number of cigarettes smoked per day.

RESULTS

Linear multilevel modeling was used in examining associations between pain and smoking. A within-person pain and smoking association was found, such that greater daily pain was linked to greater daily smoking within individuals, controlling for baseline symptoms, nicotine dependence, smoking urge, age, and gender. No between-person pain and smoking association was observed. Additionally, cancer patients with higher average pain across the 2-week assessment period were less likely to make a quit attempt (defined as a day on which participants smoked no cigarettes) during the study period.

CONCLUSIONS

The findings of this study add to a nascent literature on pain and smoking by providing initial evidence that pain may be a barrier to quitting among cancer patients who smoke and have pain. Future research examining the effectiveness of integrated pain and smoking cessation treatment in this population may be warranted.

Evaluating the role of anxiety sensitivity in barriers to cessation and reasons for quitting among smokers with asthma

The aim of the present study was to examine the unique predictive ability of anxiety sensitivity (AS) in terms of perceived barriers to cessation and smoking cessation motives among daily smokers with asthma (n = 125, 54% male, Mage = 37.7 years, SD = 12.1). As hypothesized, after controlling for the effects of race, asthma control, negative affect, and smoking rate, AS significantly predicted greater barriers to cessation, and reasons for quitting related to health concerns and self-control. Contrary to hypotheses, AS did not significantly predict external reasons for quitting. These findings suggest that smokers with asthma who are fearful of physiological arousal may be a particularly 'at-risk' population for smoking cessation difficulties due, in part, to greater perceived barriers to cessation. Interventions focused on enhancing intrinsic motivation for quitting and reducing AS may be most effective for this population.

The Moderating Role of Smoking Amount Per Day on the Relations Between Anxiety Sensitivity, Smoking Dependence, and Cognitive-Affective Aspects of Smoking Among Treatment Seeking Smokers

The current study examined the moderating effects of smoking amount per day on the relation between anxiety sensitivity and nicotine dependence, cigarette smoking outcome expectancies, and reasons for quitting smoking among 465 adult, treatment-seeking smokers (48% female; Mage = 36.6, SD = 13.5). Smoking amount per day moderated the relation between anxiety sensitivity and nicotine dependence, smoking expectancies for negative consequences and appetite control as well as intrinsic reasons for quitting. However, no moderating effect was evident for negative reinforcement expectancies. The form of the significant interactions indicated across dependent variables lower levels of smoking amount per day suppressed the relation between anxiety sensitivity and smoking related dependent variable, such that the positive relation of anxiety sensitivity to smoking dependence and cognitive-affective aspects of smoking is weaker in heavier smokers and more robust in lighter smokers.

Psychometric Characteristics of the Brief Wisconsin Inventory of Smoking Dependence Motives Among a Nonclinical Sample of Smokers

INTRODUCTION

Attempts to validate the Brief Wisconsin Inventory of Smoking Dependence Motives (WISDM) have produced mixed results. The objectives for the current research were to (1) evaluate the test-retest reliability, internal consistency, and concurrent validity for each of the motive scales (2) evaluate three models to determine fit based on previous research: (i) 11-factor model, (ii) 11-factor model with four error covariances specified by previous research, and (iii) 11-factor model with two higher order primary and secondary dependence motive factors, and (3) evaluate the discriminant and convergent validity of the Brief WISDM scales.

METHODS

Smoking adults aged 18-65 completed a survey about their smoking behaviors and nicotine dependence with a web-based instrument that was administered at a 3-month test-retest interval. Psychometric properties and test-retest reliability were evaluated for each instrument. The 11-factor Brief WISDM was evaluated with confirmatory factor analyses; the scales were evaluated for convergent and discriminant validity.

RESULTS

The Brief WISDM demonstrated good to excellent test-retest reliability. Confirmatory factor analysis showed the model with the second order primary and secondary dependence motive factors demonstrated the best fit for the data at both administrations. Discriminant validity issues were present for most of the primary dependence motive scales.

CONCLUSIONS

To date, the theoretically derived smoking motives for the Brief WISDM have demonstrated mixed support when submitted to confirmatory factor analysis. While these scales tap critical motives of nicotine dependence, further refinement of primary dependence motives is necessary to ensure each latent variable assesses a unique construct.

Withdrawal: Expanding a Key Addiction Construct

Withdrawal is an essential component of classical addiction theory; it is a vital manifestation of dependence and motivates relapse. However, the traditional conceptualization of withdrawal as a cohesive collection of symptoms that emerge during drug deprivation and decline with either the passage of time or reinstatement of drug use, may be inadequate to explain scientific findings or fit with modern theories of addiction. This article expands the current understanding of tobacco withdrawal by examining: (1) withdrawal variability; (2) underlying causes of withdrawal variability, including biological and person factors, environmental influences, and the influence of highly routinized behavioral patterns; (3) new withdrawal symptoms that allow for enhanced characterization of the withdrawal experience; and (4) withdrawal-related cognitive processes. These topics provide guidance regarding the optimal assessment of withdrawal and illustrate the potential impact modern withdrawal conceptualization and assessment could have on identifying treatment targets.

Relationships between trait urgency, smoking reinforcement expectancies, and nicotine dependence

Urgency (i.e., the tendency to act rashly during negative/positive affect) may increase vulnerability to a variety of risky behaviors. This cross-sectional study of nontreatment-seeking smokers examined the relationship between urgency, level of nicotine dependence, and smoking reinforcement expectancies. Both positive and negative urgency were associated with nicotine dependence. Mediational analyses illustrated that smoking reinforcement expectancies significantly accounted for urgency-dependence relations, with negative reinforcement expectancies displaying incremental mediational effects. If replicated and extended, these findings may support the use of treatments that modify beliefs regarding smoking reinforcement outcomes as a means of buffering the risk of nicotine dependence carried by urgency.

Acceptance and commitment therapy smoking cessation treatment for veterans with posttraumatic stress disorder: a pilot study

OBJECTIVE

Veterans with PTSD smoke at rates two to three times higher than the general population, while their quit rate is less than half that of the general population. The present study evaluated the feasibility, acceptability, and preliminary efficacy of Acceptance and Commitment Therapy for Veterans With Posttraumatic Stress Disorder (PTSD) and Tobacco Addiction (ACT-PT), which focuses on helping veterans overcome emotional challenges to quitting smoking.

METHODS

Veterans with current PTSD who smoked 15 or more cigarettes/day (N = 19) participated in an open trial of ACT-PT. Participants attended nine weekly individual counseling sessions and received eight weeks of nicotine patch therapy. Primary outcomes included feasibility and acceptability of the intervention, and secondary outcomes included expired-air carbon monoxide confirmed seven-day point prevalence abstinence, cravings, and PTSD symptoms.

RESULTS

The retention rate for ACT-PT was good (74%) and client satisfaction ratings were high. Participants made multiple quit attempts (M = 3.6, SD = 4.2) during the study period and were significantly more confident that they could quit smoking at three-month follow-up. At the end of treatment, 37% of participants were abstinent from smoking and 16% were abstinent at three-month follow-up. Overall, participants reduced their smoking by 62% at the end of treatment and 43% at three-month follow-up. PTSD symptoms and smoking urges significantly decreased from baseline to the end of treatment and three-month follow-up.

CONCLUSIONS

ACT-PT appears to be a promising smoking cessation treatment for veterans with PTSD. Future research should evaluate ACT-PT in a randomized controlled trial.

Smoking behavior: a cross-sectional study to assess the dimensionality of the brief Wisconsin inventory of smoking dependence motives and identify different typologies among young daily smokers

INTRODUCTION

The present study aims to investigate the dimensionality of the brief version of the Wisconsin Inventory of Smoking Dependence Motives (B-WISDM) and identify different smoking motivational profiles among young daily smokers (N = 375).

METHODS

We tested 3 measurement models of the B-WISDM using confirmatory factor analysis, whereas cluster analysis was used to identify the smokers' motivational profiles. Furthermore, we compared clusters toward dependence level and the number of cigarettes smoked per day using analysis of variance tests.

RESULTS

The results confirmed that the B-WISDM measures 11 first-order intercorrelated factors. The second-order model, originally proposed for the longer version of the questionnaire, showed adequate fit indices but fitted the data significantly worse than the first-order model. Five motivational clusters were identified and differed in terms of tobacco addiction and the number of cigarettes smoked per day. Although each cluster had specific features, 2 main smoker groups were distinguished: Group A (composed of 3 clusters), which was mainly characterized by high levels of secondary dependence motives, and Group B (composed of 2 clusters), in which the primary and secondary dependence motives reached similar levels. In general, the clusters of Group B were more addicted to cigarettes than Group A clusters.

CONCLUSIONS

Using the B-WISDM to identify different smoking motivational profiles has important practical implications because they might help characterize addiction, which represents the first step to help an individual quit smoking.

Negative affect is associated with alcohol, but not cigarette use in heavy drinking smokers

Co-use of alcohol and cigarettes is highly prevalent, and heavy drinking smokers represent a large and difficult-to-treat subgroup of smokers. Negative affect, including anxiety and depressive symptomatology, has been associated with both cigarette and alcohol use independently, but less is known about the role of negative affect in heavy drinking smokers. Furthermore, while some studies have shown negative affect to precede substance use, a precise biobehavioral mechanism has not been established. The aims of the present study were twofold. First, to test whether negative affect is associated with alcohol and cigarette use in a large community sample of heavy drinking smokers (n=461). And second, to examine craving as a plausible statistical mediator of the association between negative affect and alcohol and/or cigarette use. Hypothesis testing was conducted using a structural equation modeling approach with cross-sectional data. Analysis revealed a significant main effect of negative affect on alcohol use (β=0.210, p<0.05), but not cigarette use (β=0.131, p>0.10) in this sample. Mediational analysis revealed that alcohol craving was a full statistical mediator of this association (p<0.05), such that there was no direct association between negative affect and alcohol use after accounting for alcohol craving. These results are consistent with a negative reinforcement and relief craving models of alcohol use insofar as the experience of negative affect was associated with increased alcohol use, and the relationship was statistically mediated by alcohol craving, presumably to alleviate negative affect. Further longitudinal or experimental studies are warranted to enhance the causal inferences of this mediated effect.

Tobacco use and cessation for cancer survivors: an overview for clinicians

Approximately 30% of all cancer deaths in the United States are caused by tobacco use and smoking. Cancers of eighteen sites have been causally linked to smoking, the most common of which are the lung, head and neck, bladder, and esophagus. While quit rates and quit attempt rates are relatively high shortly after a cancer diagnosis, the recidivism rates are also high. Therefore, screening, treating, and preventing relapse to tobacco use is imperative among patients with and survivors of cancer. To date, research has consistently shown that a combination of pharmacologic and behavioral interventions is needed to achieve the highest smoking cessation rates, with a recent emphasis on individualized treatment as a most promising approach. Challenges in health care systems, including the lack of appropriate resources and provider training, have slowed the progress in addition to important clinical considerations relevant to the treatment of tobacco dependence (eg, a high degree of comorbidity with psychiatric disorders and other substance use disorders). However, continued tobacco use has been shown to limit the effectiveness of major cancer treatments and to increase the risk of complications and of developing secondary cancers. The authors recommend that oncology providers screen all patients for tobacco use and refer users to specialized treatment when available. Alternatively, oncology clinicians can provide basic advice on tobacco use cessation and pharmacotherapy and/or referral to outside resources (eg, quitlines). Herein, the authors summarize the current knowledge on tobacco use and its treatment, with a focus on the related available evidence for patients with and survivors of cancer.

Distress tolerance and perceived barriers to smoking cessation

BACKGROUND

The present study examined the role of emotional distress tolerance (DT) in predicting barriers to smoking cessation and number of quit attempts.

METHODS

The sample consisted of regular daily smokers (N = 126; 37 females; M age = 36.51, SD = 13.05) who completed self-report measures on affect and smoking.

RESULTS

After controlling for daily smoking rate and anxiety sensitivity, emotional DT significantly predicted internal barriers to cessation (6.9% unique variance) but not external or addiction-related barriers to cessation. Inconsistent with prediction, emotional DT did not significantly predict number of quit attempts.

CONCLUSIONS

These results suggest that individuals who are low in emotional DT believe that quitting smoking will be difficult because it takes away an important affect regulation strategy, and there may be utility in targeting emotional DT in smoking cessation interventions.

Nicotine dependence syndrome scale and craving: comparing nicotine-dependent individuals with and without comorbid alcohol dependence

INTRODUCTION

Although several studies have explored craving for certain drugs, there is limited data describing the relationship between alcohol and nicotine craving from a multidimensional perspective among individuals with comorbid nicotine dependence (ND) and alcohol dependence (AD).

METHODS

We compared a group of male patients diagnosed with ND and AD (n = 160) to a group of male patients diagnosed with ND only (n = 235). Smoking- and drinking-related clinical features were measured, including craving levels and the Nicotine Dependence Syndrome Scale (NDSS), which is a multidimensional questionnaire measuring ND. Subsequently, we studied factors that influenced smoking and alcohol craving in the ND and AD group.

RESULTS

Regarding the NDSS, the sum, priority and tolerance scores were significantly higher in the ND and AD group compared with the ND only group (P < 0.000, P < 0.000 and P = 0.001, respectively). In the comorbid group, regression analyses revealed that alcohol craving and Fagerstrom Test for Nicotine Dependence (FTND) scores contributed to nicotine craving (beta coefficient = 0.37, P = 0.005 and beta coefficient = 0.35, P = 0.026, respectively) and these two factors explained 36% of the variance). Nicotine craving appeared to be the only factor that contributed to alcohol craving (beta coefficient = 0.35, P = 0.002), and nicotine craving explained 16% of the variance.

DISCUSSION

This study may help clarify the clinical relationship between comorbid alcohol and nicotine dependence and help guide the development of effective treatment strategies for ND and AD patients.

The role of mindfulness skills in terms of distress tolerance: a pilot test among adult daily smokers

BACKGROUND AND OBJECTIVES

Low distress tolerance is associated with difficulties quitting smoking. Mindfulness is associated with improved cessation outcomes and may be one method by which to increase distress tolerance. The purpose of the current study was to examine the relationship between mindfulness skills and distress tolerance among regular smokers.

METHODS

Daily smokers (n=125; Mage=37.5, 70% male) completed self-report measures assessing smoking and emotions.

RESULTS

After controlling for age, gender, and nicotine dependence, and education the mindfulness skills of acting with awareness and accepting without judgment significantly predicted distress tolerance.

DISCUSSION AND CONCLUSIONS

For smokers, being able to pay attention to present moment vents and accept negative events without judgment is associated with a greater ability to withstand such events.

SCIENTIFIC SIGNIFICANCE

These findings suggest that mindfulness-based approaches to smoking cessation may be effective because of improvements in distress tolerance. However, future prospective and laboratory-based studies are needed to better understand the mindfulness-distress tolerance link among smokers.

Can urinary cotinine predict nicotine dependence level in smokers?

BACKGROUND

Although nicotine dependence plays a role as a main barrier for smoking cessation, there is still a lack of solid evidence on the validity of biomarkers to determine nicotine dependence in clinical settings. This study aimed to investigate whether urinary cotinine levels could reflect the severity of nicotine dependence in active smokers.

MATERIALS AND METHODS

Data regarding general characteristics and smoking status was collected using a self-administered smoking questionnaire. The Fagerstrom test for nicotine dependence (FTND) was used to determine nicotine dependence of the participants, and a total of 381 participants were classified into 3 groups of nicotine dependence: low (n=205, 53.8%), moderate (n=127, 33.3%), and high dependence groups (n=49, 12.9%). Stepwise multiple linear regression model and receiver operating characteristic (ROC) curves analyses were used to determine the validity of urinary cotinine for high nicotine dependence.

RESULTS

In correlation analysis, urinary cotinine levels increased with FTND score (r=0.567, P<0.001). ROC curves analysis showed that urinary cotinine levels predicted the high-dependence group with reasonable accuracy (optimal cut-off value=1,000 ng/mL; AUC=0.82; P<0.001; sensitivity=71.4%; specificity=74.4%). In stepwise multiple regression analysis, the total smoking period (β=0.042, P=0.001) and urinary cotinine levels (β=0.234, P<0.001) were positively associated with nicotine dependence, whereas an inverse association was observed between highest education levels (>16 years) and nicotine dependence (β=-0.573, P=0.034).

CONCLUSIONS

The results of this study support the validity of using urinary cotinine levels for assessment of nicotine dependence in active smokers.

Factors predicting smoking in a laboratory-based smoking-choice task

This study aimed to expand the current understanding of smoking maintenance mechanisms by examining how putative relapse risk factors relate to a single behavioral smoking choice using a novel laboratory smoking-choice task. After 12 hr of nicotine deprivation, participants were exposed to smoking cues and given the choice between smoking up to two cigarettes in a 15-min window or waiting and receiving four cigarettes after a delay of 45 min. Greater nicotine dependence, higher impulsivity, and lower distress tolerance were hypothesized to predict earlier and more intensive smoking. Out of 35 participants (n = 9 women), 26 chose to smoke with a median time to a first puff of 1.22 min (SD = 2.62 min, range = 0.03-10.62 min). Survival analyses examined latency to first puff, and results indicated that greater pretask craving and smoking more cigarettes per day were significantly related to smoking sooner in the task. Greater behavioral disinhibition predicted shorter smoking latency in the first 2 min of the task, but not at a delay of more than 2 min. Lower distress tolerance (reporting greater regulation efforts to alleviate distress) was related to more puffs smoked and greater nicotine dependence was related to more time spent smoking in the task. This novel laboratory smoking-choice paradigm may be a useful laboratory analog for the choices smokers make during cessation attempts and may help identify factors that influence smoking lapses.

The Fagerström test for nicotine dependence: do revisions in the item scoring enhance the psychometric properties?

Despite widespread use, considerable literature has shown that the Fagerström Test for Nicotine Dependence (FTND; Heatherton, Kozlowski, Frecker, & Fagerström, 1991) has questionable psychometric properties, generally reflecting relatively poor properties of reliability and validity. One factor that may be affecting the psychometric qualities of the scale is the use of a dichotomous, forced-choice response format for certain items, in which respondents are asked to answer each question with a Yes or No response. This scoring approach is especially problematic when used to measure dimensional constructs, such as nicotine dependence, in which a dimensional construct is forced into a categorical construct. The purpose of the current study was to examine whether revising the response format utilized in the FTND would lead to an enhancement in the psychometric properties of this scale. This question was examined by removing the forced-choice response criteria on items 2, 5, and 6 of the FTND and revising the response options to reflect a 4-point Likert response set (0 = never, 1 = sometimes, 2 = most of the time, 3 = always). Participants consisted of 343 smokers from the community. Results revealed that the revised scoring approach resulted in a significant incremental improvement in scale reliability and enhanced convergent validity, showing a stronger association with smoking outcomes than the FTQ or FTND. Findings are discussed in terms of recommendations for scale revision and usage.

A randomized clinical trial of smoking cessation treatments provided in HIV clinical care settings

INTRODUCTION

Identifying successful smoking treatment interventions and methods of delivery is critical given the smoking rates among HIV-positive populations and the medical implications of smoking in this population. This study compared the efficacy of 3 smoking cessation interventions provided in HIV clinical treatment settings.

METHODS

Following a baseline assessment, 209 HIV-positive smokers were randomly assigned to 1 of 3 conditions in a parallel group design. Treatment conditions were individual counseling plus nicotine replacement treatment (NRT), a computer-based Internet smoking treatment plus NRT, and self-help plus NRT. Smoking status was determined at follow-up assessments completed at 12, 24, 36, and 52 weeks following treatment initiation.

RESULTS

Cessation rates ranged from 15% to 29%; however, no statistically significant differences in abstinence were found among the treatment conditions over time. Those employed, those who reported a greater desire to quit, or those with lower mood disturbance scores were more likely to achieve abstinence (p < .01). The number of cigarettes participants reported smoking in the 24hr prior to each assessment significantly declined over time (p < .001).

CONCLUSIONS

Although we found no differences in abstinence rates across groups, the results indicate that integration of smoking cessation interventions is feasible in HIV clinical treatment settings, and cessation results are promising. The overall abstinence rates we report are comparable to those found in similar treatment studies across multiple populations. Further research is warranted.

What aspect of dependence does the fagerström test for nicotine dependence measure?

Although the Fagerström Test for Nicotine Dependence (FTND) and the Heaviness of Smoking Index (HSI) are widely used, there is a uncertainty regarding what is measured by these scales. We examined associations between these instruments and items assessing different aspects of dependence. Adult current smokers (n = 422, mean age 33.3 years, 61.9% female) completed a web-based survey comprised of items related to demographics and smoking behavior plus (1) the FTND and HSI; (2) the Autonomy over Tobacco Scale (AUTOS) with subscales measuring Withdrawal, Psychological Dependence, and Cue-Induced Cravings; (3) 6 questions tapping smokers' wanting, craving, or needing experiences in response to withdrawal and the latency to each experience during abstinence; (4) 3 items concerning how smokers prepare to cope with periods of abstinence. In regression analyses the Withdrawal subscale of the AUTOS was the strongest predictor of FTND and HSI scores, followed by taking precautions not to run out of cigarettes or smoking extra to prepare for abstinence. The FTND and its six items, including the HSI, consistently showed the strongest correlations with withdrawal, suggesting that the behaviors described by the items of the FTND are primarily indicative of a difficulty maintaining abstinence because of withdrawal symptoms.

Are tobacco dependence and withdrawal related amongst heavy smokers? Relevance to conceptualizations of dependence

Measured tobacco dependence is typically only modestly related to tobacco withdrawal severity among regular smokers making a quit attempt. The weak association between dependence and withdrawal is notable because it conflicts with core theories of dependence and because both measures predict cessation outcomes, suggesting they both index a common dependence construct. This study used data from a smoking cessation comparative effectiveness trial (N = 1504) to characterize relations of tobacco dependence with craving and negative affect withdrawal symptoms using multiple dependence measures and analytic methods to detect both additive and interactive effects and to determine whether withdrawal meaningfully mediates the influence of dependence on smoking cessation. We conclude: (a) Although univariate analyses suggest dependence and withdrawal measures are only modestly interrelated, more powerful analytic techniques show they are, in fact, meaningfully related and their shared variance is associated with cessation likelihood; (b) there are clear differences between craving and negative affective withdrawal symptoms, with the former more related to smoking heaviness and the latter related to trait measures of negative affect; moreover, craving more strongly mediates dependence effects on cessation; and (c) both craving and negative affect withdrawal symptoms are strongly related to a pattern of regular smoking that is sensitive to the passage of time and powerfully affected by smoking cues. These findings support models that accord an important role for associative processes and withdrawal symptoms, especially craving, in drug dependence. The findings also support the use of withdrawal variables as criteria for the evaluation of dependence measures.

Asthma and its relation to smoking behavior and cessation motives among adult daily smokers

Despite the negative effects of smoking on lung functioning and overall health, smoking is more prevalent among individuals with asthma compared to those without asthma. The purpose of this study was to examine the predictive ability of asthma diagnosis in terms of smoking behavior and reasons for quitting. Participants were 251 regular daily smokers: 125 smokers with self-reported, physician-diagnosed asthma and 126 smokers without asthma. Asthma diagnosis significantly predicted age of regular smoking onset, number of quit attempts, and reasons for quitting related to self-control suggesting that smokers with asthma may have more difficulty quitting and unique reasons for quitting.

The interaction of nicotine withdrawal and panic disorder in the prediction of panic-relevant responding to a biological challenge

The current investigation evaluated nicotine withdrawal symptoms elicited by 12 hours of smoking deprivation on anxious and fearful responding to bodily sensations among daily smokers with and without panic disorder (PD). It was hypothesized that smokers with PD who were experiencing greater levels of nicotine withdrawal would experience the greatest levels of fearful responding to, and delayed recovery from, a 10% carbon dioxide-enriched air (CO₂) biological challenge procedure. Participants were 58 adults who reported smoking 19.72 cigarettes daily (SD = 7.99). Results indicated that nicotine withdrawal and PD status interacted to predict greater postchallenge panic attack symptoms. Also, individuals with PD initially evidenced a quicker decrease in subjective anxiety following the challenge, but their rate of recovery decelerated over time as compared to those without PD. There was, however, no significant interaction for change in subjective anxiety pre- to postchallenge. Results are discussed in relation to the role of nicotine withdrawal in anxious and fearful responding for smokers with PD.

Therapeutic education in cardiovascular diseases: state of the art and perspectives

OBJECTIVE

To assess the impact of therapeutic education programmes for Coronary Artery Disease (CAD) and Chronic Heart Failure (CHF), as well as patients' expectations and education needs, tips to improve adherence to lifestyle modifications, and education materials.

METHOD

We conducted a systematic review of the literature from 1966 to 2010 on Medline and the Cochrane Library databases using following key words: "counselling", "self-care", "self-management", "patient education" and "chronic heart failure", "CAD", "coronary heart disease", "myocardial infarction", "acute coronary syndrome". Clinical trials and randomized clinical trials, as well as literature reviews and practical guidelines, published in English and French were analysed.

RESULTS

Therapeutic patient education (TPE) is part of the non-pharmacological management of cardiovascular diseases, allowing patients to move from an acute event to the effective self-management of a chronic disease. Large studies clearly showed the efficacy of TPE programmes in changing cardiac patients' lifestyle. Favourable effects have been proved concerning morbidity and cost-effectiveness even though there is less evidence for mortality reduction. Numerous types of intervention have been studied, but there are no recommendations about standardized rules and methods to deliver information and education, or to evaluate the results of TPE. The main limit of TPE is the lack of results for adherence to long-term lifestyle modifications.

CONCLUSION

The efficacy of TE in cardiovascular diseases could be improved by optimal collaboration between acute cardiac units and cardiac rehabilitation units. The use of standardized rules and methods to deliver information and education and to assess their effects could reinforce this collaboration. Networks for medical and paramedical TPE follow-up in tertiary prevention could be organized to improve long-term results.

Intensive intervention for alcohol-dependent smokers in early recovery: a randomized trial

INTRODUCTION

The purpose of this study was to investigate the efficacy of an intensive tobacco cessation intervention for alcohol-dependent smokers in early recovery.

METHODS

A total of 162 alcohol-dependent smokers were randomized to either intensive intervention for smoking cessation or usual care. The intensive intervention consisted of 16 sessions of individual cognitive behavior therapy (CBT) and combination nicotine replacement therapy that lasted 26 weeks. Usual care involved referral to a free-standing smoking cessation program that provided smoking cessation counseling of varying duration and guideline-concordant medications. The primary cessation outcome was verified 7-day point prevalence abstinence (PPA) at 12, 26, 38, and 52 weeks.

RESULTS

At 12 and 26 weeks, the verified 7-day point-prevalence quit rate was significantly higher for the intensive intervention group than for the usual care group (both p=0.03). However, the quit rates for the two treatment groups were not significantly different at 38 or 52 weeks. Verified 30-day alcohol abstinence rates were not significantly different for the two treatment groups at any of the follow-up assessments.

CONCLUSIONS

The intensive smoking cessation intervention yielded a higher short-term smoking quit rate without jeopardizing sobriety. A chronic care model might facilitate maintenance of smoking cessation during the first year of alcohol treatment and perhaps for longer periods of time. It is hoped that studies such as this will inform the development of more effective interventions for concurrent alcohol and tobacco use disorders.

Panic attack history and anxiety sensitivity in relation to cognitive-based smoking processes among treatment-seeking daily smokers

INTRODUCTION

Empirical research has found that panic attacks are related to increased risk of more severe nicotine withdrawal and poor cessation outcome. Anxiety sensitivity (AS; fear of anxiety and related sensations) has similarly been found to be related to an increased risk of acute nicotine withdrawal and poorer cessation outcome. However, research has yet to examine the relative contributions of panic attacks and AS in terms of cognitive-based smoking processes (e.g., negative reinforcement smoking expectancies, addictive and negative affect-based reduction smoking motives, barriers to cessation, problem symptoms experienced while quitting).

METHOD

Participants (n = 242; 57.4% male; M (age) = 38.1) were daily smokers recruited as a part of a larger randomized control trial for smoking cessation. It was hypothesized that both panic attacks and AS would uniquely and independently predict the studied cognitive-based smoking processes.

RESULTS

As hypothesized, AS was uniquely and positively associated with all smoking processes after controlling for average number of cigarettes smoked per day, current Axis I diagnosis, and participant sex. However, panic attack history was only significantly related to problem symptoms experienced while quitting smoking.

CONCLUSIONS

Although past research has demonstrated significant associations between panic attacks and certain aspects of cigarette smoking (e.g., severity of nicotine withdrawal; lower abstinence rates, and negative affect reduction motives), the present findings suggest that AS may be more relevant to understanding beliefs about and motives for smoking behavior as well as perceptions of cessation-related difficulties.

[Tests for evaluating tobacco dependence]

The primary reason why there is such a heavy burden of tobacco smoking induced illness and death is dependence on nicotine which makes it difficult for smokers to quit. For clinical or research purposes, the degree of dependence, the intensity of the withdrawal syndrome and/or craving have been evaluated by different scales. This review provides a list of questionnaires that are used in smoking cessation. It pays particular attention to the validated and translated resources that are available in French. Research should be conducted in order to provide French speaking smoking cessation specialists with all the relevant scales allowing better evaluation of tobacco dependence.

Peering through the smoke: the effect of parental smoking behavior and addiction on daily smokers' attentional bias to smoking cues

Although previous research has demonstrated that individuals with parents who smoke are more likely to become smokers and are less successful in smoking cessation efforts compared with those without a smoking parent, the reasons for this link have not been established. In the current study, implicit attentional bias to smoking-related cues was investigated in college-age smokers, based on models of addiction that suggest that attention to drug-related cues plays an important role in drug addiction. Sixty-one participants completed a dot-probe task to measure attentional bias to smoking-related and matched non-smoking-related control pictures. Results indicated that while those who reported smoking occasionally did not demonstrate an attentional bias, daily smokers who had a smoking parent showed more of an attentional bias to the smoking cues than those without a smoking parent, but only to cues that did not contain human content. In addition to parental influence, nicotine dependence explained a significant portion of the variance in the attentional bias for daily smokers. Implications for models of nicotine addiction and the development of smoking cessation programs are discussed.

DSM criteria for tobacco use disorder and tobacco withdrawal: a critique and proposed revisions for DSM-5

AIMS

This paper aims to identify appropriate criteria for tobacco dependence assessment, evaluate relevant research and suggest revisions that may be incorporated into DSM-5.

METHODS

Desirable conceptual and psychometric features of tobacco dependence assessments were identified, including the types of outcomes against which such assessment should be validated. DSM-IV criteria were matched against these criteria and compared with other dependence measures.

RESULTS

DSM-IV criteria were found to be ambiguous, little used in tobacco research, and have relatively low predictive validity. Other dependence measures were found to have greater validity in the prediction of important dependence features such as relapse likelihood. Strength of urges to smoke on typical smoking days and during abstinence, markers of nicotine intake or frequency of smoking and latency to smoke soon after waking were found to be useful dependence measures.

CONCLUSION

The use and utility of DSM-5 will be enhanced by eliminating most DSM-IV criteria and adding new ones based on smoking pattern, smoking heaviness, and the severity of craving during periods of smoking and withdrawal.

Main and interactive effects of emotion dysregulation and breath-holding duration in relation to panic-relevant fear and expectancies about anxiety-related sensations among adult daily smokers

The current study investigated the main and interactive effects of emotion dysregulation and distress tolerance in relation to panic-relevant variables among daily smokers. The sample consisted of 172 adults (61.2% male; M(age)=31.58, SD=11.51), who reported smoking an average of 15.99 cigarettes per day (SD=10.00). Results indicated that both emotion dysregulation and distress tolerance were significantly related to interoceptive fear and agoraphobia. Additionally, emotion dysregulation, but not distress tolerance, was significantly related to anxiety sensitivity. All effects were evident above and beyond the variance accounted for by average cigarettes per day, tobacco-related physical illness, and panic attack history. The interaction between emotion dysregulation and distress tolerance significantly predicted interoceptive and agoraphobic fears as well as the cognitive component of anxiety sensitivity. Such findings underscore the importance of emotion dysregulation and distress tolerance in regard to panic-specific fear and expectancies about anxiety-related sensations among daily smokers.

Anxiety sensitivity and cognitive-based smoking processes: testing the mediating role of emotion dysregulation among treatment-seeking daily smokers

The current study investigated whether emotion dysregulation (difficulties in the self-regulation of affective states) mediated relationships between anxiety sensitivity (fear of anxiety and related sensations) and cognitive-based smoking processes. Participants (n = 197; 57.5% male; mean age = 38.0 years) were daily smokers recruited as part of a randomized control trial for smoking cessation. Anxiety sensitivity was uniquely associated with all smoking processes. Moreover, emotion dysregulation significantly mediated relationships between anxiety sensitivity and the smoking processes. Findings suggest that emotion dysregulation is an important construct to consider in relationships between anxiety sensitivity and cognitive-based smoking processes among adult treatment-seeking smokers.

Expectancies regarding the interaction between smoking and substance use in alcohol-dependent smokers in early recovery

The purpose of this study was to investigate expectancies regarding the interaction between cigarette smoking and use of alcohol among alcohol-dependent smokers in early recovery, using the Nicotine and Other Substances Interaction Expectancies Questionnaire (NOSIE). Participants were 162 veterans, 97% male, with a mean age of 50 years, enrolled in a clinical trial aimed at determining the efficacy of an intensive smoking cessation intervention versus usual care. At baseline, participants were assessed on measures of smoking behavior, abstinence thoughts about alcohol and tobacco use, symptoms of depression, and smoking-substance use interaction expectancies. In addition, biologically verified abstinence from tobacco and alcohol was assessed at 26 weeks. Participants reported that they expected smoking to have less of an impact on substance use than substance use has on smoking (p < .001). Severity of depressive symptoms was significantly associated with the expectancy that smoking provides a way of coping with the urge to use other substances (p < .01). The expectation that smoking increases substance urges/use was predictive of prospectively measured and biologically verified abstinence from smoking at 26 weeks (p < .03). The results add to our knowledge of smoking-substance use interaction expectancies among alcohol-dependent smokers in early recovery and will inform the development of more effective counseling interventions for concurrent alcohol and tobacco use disorders.

Nicotine dependence among Chinese city dwellers: a population-based cross-sectional study

INTRODUCTION

Although nicotine addiction is thought to be the primary driver of tobacco smoking, few studies have examined nicotine dependence among Chinese mainland smokers.

METHODS

A population-based cross-sectional study was designed. Subjects (4735) aged 15 years and older residents were drawn from six cities in China through a multistage systematic sampling procedure. Nicotine dependence of respondents was assessed in a face-to-face interview using the 6-item Mandarin Chinese version of the Fagerström Test for Nicotine Dependence (FTND). A multilevel regression model, accounting for cluster sampling, was used to identify correlates of dependence.

RESULTS

Among females, only 4.2% (n = 115) were smokers (2.5% daily, 1.7% occasional). Subsequent analysis focused on males, of whom 50.8% (n = 1477) were smokers (38.9% daily, 11.9% occasional). The average FTND score was 2.89 (95% CI: 2.77-3.01) among all current smokers. Daily smokers had a significantly higher FTND score (3.49, 95% CI: 3.35-3.63) than occasional smokers (1.12, 95% CI: 0.98-1.26) (p < .01). Of all smokers, 27.1% were considered dependent based on FTND ≥ 4. Among daily smokers, FTND scores were negatively associated with age at smoking initiation, education, and self-efficacy for quitting smoking. FTND was associated (negatively) with income among occasional smokers only. There were regional differences in FTND scores among daily smokers.

CONCLUSIONS

Cigarette smoking is highly prevalent among Chinese males but rare among Chinese females. Occasional smoking is also common among males. Only 3.3% of occasional male smokers appear dependent by FTND criteria. Dependence varies by smoking history and demographics. These findings have implications for design and implementation of smoking cessation interventions.

Effectiveness of adding relapse prevention materials to telephone counseling

The purpose of this study was to examine the effectiveness of adding the Forever Free relapse prevention materials to telephone counseling provided by the Arkansas quitline. Results suggest that the addition of Forever Free materials to telephone counseling does not improve quit rates for those participants who receive at least one session of counseling and nicotine patches; however, for those participants unwilling or unable to receive nicotine patches, the addition of the Forever Free relapse prevention materials doubled the abstinence rate and increased the odds of abstinence by nearly 70% 6 months after treatment (20.9% versus 10.6%; OR = 1.69; CI = 1.02-2.78; p = .04). Given the recent proliferation of quitline services and the variety of services provided, these results can address concerns about enhancing treatment outcomes for certain groups.

Offer of a weight management program to overweight and obese weight-concerned smokers improves tobacco dependence treatment outcomes

Weight concern is a common and significant barrier to abstinence for many smokers. This quasi-experimental pilot study used multivariate logistic regression to examine the effects of offering a weight management treatment program on tobacco dependence treatment outcomes. Age, gender, ethnicity, educational level, nicotine dependence level, body mass index, and concern about weight gain were entered as factors/covariates to account for differences between groups. Offering a weight management program increased attendance at the first scheduled contact (88.1% vs. 71.6%; OR = 2.93; p = .029) and increased 6-month abstinence (21.4% vs. 10.1%; OR = 2.42; p = .052). With factors and covariates included in the multivariate models to account for group differences, those offered weight management were five times more likely to attend their first session (OR = 5.10; 95% CI 1.53-16.98; p = .008) and three times more likely to be abstinent 6 months after tobacco treatment (OR = 2.98; 95% CI = 1.09-8.17; p = .033). Proactively informing weight-concerned, overweight/obese smokers about the availability of a weight management program as an incentive for completing treatment for tobacco dependence may improve tobacco treatment outcomes. 

Risk factors for drug dependence among out-patients on opioid therapy in a large US health-care system

AIMS

Our study sought to assess the prevalence of and risk factors for opioid drug dependence among out-patients on long-term opioid therapy in a large health-care system.

METHODS

Using electronic health records, we identified out-patients receiving 4+ physician orders for opioid therapy in the past 12 months for non-cancer pain within a large US health-care system. We completed diagnostic interviews with 705 of these patients to identify opioid use disorders and assess risk factors.

RESULTS

Preliminary analyses suggested that current opioid dependence might be as high as 26% [95% confidence interval (CI) = 22.0-29.9] among the patients studied. Logistic regressions indicated that current dependence was associated with variables often in the medical record, including age <65 [odds ratio (OR) = 2.33, P = 0.001], opioid abuse history (OR = 3.81, P < 0.001), high dependence severity (OR = 1.85, P = 0.001), major depression (OR = 1.29, P = 0.022) and psychotropic medication use (OR = 1.73, P = 0.006). Four variables combined (age, depression, psychotropic medications and pain impairment) predicted increased risk for current dependence, compared to those without these factors (OR = 8.01, P < 0.001). Knowing that the patient also had a history of severe dependence and opioid abuse increased this risk substantially (OR = 56.36, P < 0.001).

CONCLUSION

Opioid misuse and dependence among prescription opioid patients in the United States may be higher than expected. A small number of factors, many documented in the medical record, predicted opioid dependence among the out-patients studied. These preliminary findings should be useful in future research efforts.