Paul T. Harrell

Electronic Nicotine Delivery Systems (''E-cigarettes''): Review of Safety and Smoking Cessation Efficacy

Background and Objectives Cigarette smoking is common among cancer patients and is associated with negative outcomes. Electronic nicotine delivery systems (“e-cigarettes”) are rapidly growing in popularity and use, but there is limited information on their safety or effectiveness in helping individuals quit smoking. Data Sources The authors searched PubMed, Web of Science, and additional sources for published empirical data on safety and use of electronic cigarettes as an aid to quit smoking. Review Methods We conducted a structured search of the current literature up to and including November 2013. Results E-cigarettes currently vary widely in their contents and are sometimes inconsistent with labeling. Compared to tobacco cigarettes, available evidence suggests that e-cigarettes are often substantially lower in toxic content, cytotoxicity, associated adverse effects, and secondhand toxicity exposure. Data on the use of e-cigarettes for quitting smoking are suggestive but ultimately inconclusive. Conclusions Clinicians are advised to be aware that the use of e-cigarettes, especially among cigarette smokers, is growing rapidly. These devices are unregulated, of unknown safety, and of uncertain benefit in quitting smoking. Implications for Practice In the absence of further data or regulation, oncologists are advised to discuss the known and unknown safety and efficacy information on e-cigarettes with interested patients and to encourage patients to first try FDA-approved pharmacotherapies for smoking cessation.

Latent classes of heroin and cocaine users predict unique HIV/HCV risk factors.

BACKGROUND Patterns of heroin and cocaine use vary and may be associated with unique risk factors for bloodborne infections. METHODS Latent class analysis identified sub-populations of 552 heroin and cocaine users in Baltimore, Maryland. Using latent class regression, these classes were analyzed for associations with demographic characteristics, risky behaviors, Hepatitis C, and HIV. RESULTS Three classes were found: Crack/Nasal-Heroin users (43.5%), Polysubstance users (34.8%), and Heroin Injectors (21.8%). Compared to Polysubstance users, Crack/Nasal-Heroin users were almost 7 times more likely to identify as Black (OR=6.97, 95% CI=4.35-11.2). Sharing needles was over 2.5 times more likely among Polysubstance users than among Heroin Injectors (OR=2.66, 95% CI=1.49-4.75). Crack/Nasal-Heroin users were 2.5 times more likely than Polysubstance users to exchange drugs for sex (OR=2.50, 95% CI=1.22-5.13). Crack/Nasal-Heroin users were less likely than Heroin Injectors to have Hepatitis C (OR=0.10, 95% CI=0.06-0.18), but no significant differences were found for HIV. CONCLUSIONS Subpopulations of cocaine and heroin users differed in demographic classifications, HIV-risk behaviors, and Hepatitis C infection. All subpopulations included substantial numbers of HIV-positive individuals. Findings provide further evidence that non-injection drug users face significant infectious disease risk.

Early onset of drug and polysubstance use as predictors of injection drug use among adult drug users

Early onset of alcohol, marijuana, and cigarette use is an indicator of later substance use problems in adulthood such as alcohol or other drug dependence. This paper seeks to address the association between early onset alcohol, marijuana, cigarette, and polysubstance use with injection drug use among recent illicit drug users. The current study used baseline data from the Baltimore site of the NEURO-HIV Epidemiologic Study, an investigation of neuropsychological and social-behavioral risk factors of HIV, hepatitis A, hepatitis B, and Hepatitis C among both injection and non-injection drug users in Baltimore, Maryland. The present study used a subset (N=651) of the larger parent study that identified as White or Black, and reported any drug use in the past 6 months. In the full sample slightly more than half (52.5%) of study participants were IDUs. IDUs differed from non-IDUs on age of initiation for cigarettes, marijuana, and alcohol, with IDUs initiating the use of all three substances significantly earlier than non-IDUs. IDUs also had significantly greater proportions of early onset of alcohol (χ(2)=19.71, p<.01), cigarette (χ(2)=11.05, p<.01), marijuana (χ(2)=10.83, p<.01), and polysubstance use (χ(2)=23.48, p<.01) than non-IDUs. After adjusting for age, gender, and race/ethnicity, only participants identified as early onset alcohol users (AOR=1.47, 95% CI: 1.00-2.18) and early onset polysubstance users (AOR=1.62, 95% CI: 1.10-2.38) were more likely to have IDU status than those who reported initiating substance use later. IDU status was then stratified by race/ethnicity. After controlling for age and gender, only early polysubstance use was a significant predictor of IDU status for Whites (AOR=2.06, 95% CI: 1.07-3.93). Consistent with literature on early substance initiation and later illicit substance use, early onset of alcohol and polysubstance use is an important risk factor for IDU in adulthood.

Expectancies for Cigarettes, E-Cigarettes, and Nicotine Replacement Therapies Among E-Cigarette Users (aka Vapers)

INTRODUCTION Use of e-cigarettes has been increasing exponentially, with the primary motivation reported as smoking cessation. To understand why smokers choose e-cigarettes as an alternative to cigarettes, as well as to US Food and Drug Administration (FDA)--approved nicotine replacement therapies (NRT), we compared outcome expectancies (beliefs about the results of drug use) for the three nicotine delivery systems among vapers, i.e., e-cigarette users, who were former smokers. METHODS Vapers (N = 1,434) completed an online survey assessing 14 expectancy domains as well as perceived cost and convenience. We focused on comparisons between e-cigarettes and cigarettes to determine the attraction of e-cigarettes as a smoking alternative and between e-cigarettes and NRT to determine perceived advantages of e-cigarettes over FDA-approved pharmacotherapy. RESULTS Participants believed that e-cigarettes, in comparison to conventional cigarettes, had fewer health risks; caused less craving, withdrawal, addiction, and negative physical feelings; tasted better; and were more satisfying. In contrast, conventional cigarettes were perceived as better than e-cigarettes for reducing negative affect, controlling weight, providing stimulation, and reducing stress. E-cigarettes, compared to NRT, were perceived to be less risky, cost less, cause fewer negative physical feelings, taste better, provide more satisfaction, and be better at reducing craving, negative affect, and stress. Moderator analyses indicated history with ad libitum forms of NRT was associated with less positive NRT expectancies. CONCLUSIONS The degree to which expectancies for e-cigarettes differed from expectancies for either tobacco cigarettes or NRT offers insight into the motivation of e-cigarette users and provides guidance for public health and clinical interventions to encourage smoking-related behavior change.

Cigarette smoking and drug use among a nationally representative sample of HIV-positive individuals

BACKGROUND AND OBJECTIVES Among HIV-positive populations, the prevalence of cigarette smoking remains disproportionately high and is associated with significant morbidity and mortality. Little is known about this topic among HIV-positive persons in the general population. METHODS Data came from the 2005 to 2011 National Survey on Drug Use and Health (NSDUH) public use data files. Unadjusted and adjusted multinomial logistic regression analyses explored the associations between socio-demographic, drug and alcohol use, and drug and/or alcohol treatment characteristics with smoking status among HIV-positive individuals (n = 349). RESULTS More than 40% of the sample was current smokers. In adjusted analyses, females (aRRR = .11, 95% CI = .03-.41) and participants who had never been married (aRRR = .19, 95% CI = .05-.58), were more likely to be former smokers than never smokers. Females (aRRR = .37, 95% CI = .14-.96) and individuals older than age 35 (aRRR = .37, 95% CI = .16-.89) were less likely to be current smokers than never smokers. Conversely, previously married persons (aRRR = 5.72, 95% CI = 1.40-23.31), participants reporting binge drinking (aRRR = 5.96, 95% CI = 2.27-15.64), and lifetime drug or alcohol treatment (aRRR = 5.12, 95% CI = 2.09-12.55) were more likely to be current smokers than never smokers. CONCLUSIONS Findings help confirm the high prevalence of smoking among HIV-positive persons suggesting the need for integrated substance use and smoking cessation treatment among HIV-positives. SCIENTIFIC SIGNIFICANCE The present findings have implications for the development and implementation of targeted smoking cessation programs for HIV-positive smokers.

Electronic cigarettes in adults in outpatient substance use treatment: Awareness, perceptions, use, and reasons for use

BACKGROUND AND OBJECTIVES Most studies on e-cigarettes have come from population-based surveys. The current research aimed to provide initial data on e-cigarette awareness, perceptions, use, and reasons for use among adults seeking substance use treatment. METHODS A survey was conducted among 198 participants ≥18 years old in a community-based outpatient substance use treatment program. RESULTS Of the 198 participants, 69% currently smoked cigarettes, 92% were aware of e-cigarettes, and 58% had ever used e-cigarettes. The proportion of the number of participants who had ever used e-cigarettes to the number who currently smoked (89.7%) appeared higher than the corresponding proportion in the 2012-13 National Adult Tobacco Survey (78.3%). Almost half of the sample who reported ever using e-cigarettes endorsed quitting or reducing smoking as a reason for use, and 32% endorsed reasons for use relating to curiosity/experimentation. A greater likelihood of e-cigarette ever-use was significantly associated with younger age (adjusted odds ratio [AOR] = 0.94, 95%confidence interval [CI] = 0.90, 0.98) and perceptions related to using e-cigarettes in public places where smoking cigarettes is not allowed (AOR = 2.96, 95%CI = 1.18, 7.42) but was not associated with primary drug of choice. DISCUSSION AND CONCLUSIONS E-cigarette use in adults seeking substance use treatment appears higher than it is in the US general population of smokers. The high frequency of use may be due to curiosity/experimentation or attempts to quit or reduce smoking. SCIENTIFIC SIGNIFICANCE Future research may consider how e-cigarettes interact with other substance use and affect high rates of nicotine and tobacco use in this population.

Latent class analysis of polysubstance use, sexual risk behaviors, and infectious disease among South African drug users.

BACKGROUND HIV transmission risk among non-injection drug users is high due to the co-occurrence of drug use and sexual risk behaviors. The purpose of the current study was to identify patterns of drug use among polysubstance users within a high HIV prevalence population. METHODS The study sample included 409 substance users from the Pretoria region of South Africa. Substances used by 20% or more the sample included: cigarettes, alcohol, marijuana and heroin in combination, marijuana and cigarettes in combination, and crack cocaine. Latent class analysis was used to identify patterns of polysubstance use based on types of drugs used. Multivariate logistic regression analyses compared classes on demographics, sexual risk behavior, and disease status. RESULTS Four classes of substance use were found: MJ+Cig (40.8%), MJ+Her (30.8%), Crack (24.7%), and Low Use (3.7%). The MJ+Cig class was 6.7 times more likely to use alcohol and 3 times more likely to use drugs before/during sex with steady partners than the Crack class. The MJ+Cig class was 16 times more likely to use alcohol before/during sex with steady partners than the MJ+Her class. The Crack class was 6.1 times more likely to engage in transactional sex and less likely to use drugs before/during steady sex than the MJ+Her class. CONCLUSIONS Findings illustrate patterns of drug use among a polysubstance using population that differ in sexual risk behavior. Intervention strategies should address substance use, particularly smoking as a route of administration (ROA), and sexual risk behaviors that best fit this high-risk population.

Gender differences in use and expectancies of E-cigarettes: Online survey results

INTRODUCTION Given the rapid increase in e-cigarette use, it is important to understand factors that may contribute to their initiation and maintenance. Because gender differences in tobacco use, product preferences, and expectancies are well established, similar gender differences may exist with e-cigarettes. The aim of this study was to identify gender differences among e-cigarette users in patterns of use, reasons for initiation and maintenance, and outcome expectancies regarding e-cigarettes. METHODS Participants (N=1815) completed an online survey from August through November, 2013. We assessed sociodemographics, smoking and e-cigarette history and use, and expectancies about e-cigarettes. RESULTS We found gender differences in type of e-cigarette used, flavors used, nicotine dosage, source of information about e-cigarettes, place of purchase, and use of e-cigarettes where smoking is prohibited. In addition, males were more likely to report initiating e-cigarette use to quit smoking due to health concerns, whereas females were more likely to report initiation based on recommendations from family and friends. Males reported higher attributions for maintenance of e-cigarette use related to positive reinforcement (enjoyment), whereas females reported higher negative reinforcement attributions (stress reduction or mood management). Males reported more positive expectancies about e-cigarettes, including taste, social facilitation, and energy, whereas women rated e-cigarettes higher for weight control. Males also reported greater addiction-related e-cigarette expectancy than females. CONCLUSIONS Many of the gender differences with e-cigarettes parallel those previously found with traditional cigarette smoking. Although effect sizes associated with these differences were small, the results may help advance research and intervention development with respect to e-cigarette initiation, maintenance and cessation.

Cigarette smoking, illicit drug use, and routes of administration among heroin and cocaine users

Cigarette smoking is ubiquitous among illicit drug users. Some have speculated that this may be partially due to similarities in the route of administration. However, research examining the relationship between cigarette smoking and routes of administration of illicit drugs is limited. To address this gap, we investigated sociodemographic and drug use factors associated with cigarette smoking among cocaine and heroin users in the Baltimore, Maryland community (N=576). Regular and heavy cigarette smokers were more likely to be White, have a history of a prior marriage, and have a lower education level. Regular smoking of marijuana and crack was associated with cigarette smoking, but not heavy cigarette smoking. Injection use was more common among heavy cigarette smokers. In particular, regular cigarette smokers were more likely to have a lifetime history of regularly injecting heroin. Optimal prevention and treatment outcomes can only occur through a comprehensive understanding of the interrelations between different substances of abuse.

Injection and non-injection drug use and infectious disease in Baltimore City: Differences by race

PURPOSE The current study examines differences in the prevalence of biologically-confirmed hepatitis C virus (HCV), HIV, and coinfection between Black and White adult cocaine/heroin users across three drug use subgroups identified in previous research (Harrell et al., 2012): non-injection smoking crack/nasal heroin users, heroin injectors, and polydrug injectors. RESULTS 59% of the 482 participants in the study were male. Significant race differences emerged between drug use subgroup memberships. Non-injection smoking crack/nasal heroin users were predominantly Black (75%), while heroin injectors and polydrug injectors were predominantly White (69% and 72%, respectively). Polydrug injectors accounted for nearly three quarters of the HCV positive diagnoses in Whites. Though HIV disease status, stratified by race, did not differ significantly between drug use subgroups, the non-injection smoking crack/nasal heroin subgroup contained over half of the HIV positive diagnoses in the sample and was predominantly Black. Despite much lower rates of injection, Blacks (8%) had a higher prevalence of coinfection than Whites (3%; X(2) (2)=6.18, p=.015). CONCLUSIONS The current findings are consistent with trends in the recent HIV transmission statistics where sexual activity has overtaken injection drug use as a HIV risk factor. The current findings also provide further support to the notion of injection drug use as an exceedingly high-risk behavior for HCV and coinfection, specifically those who are polysubstance injectors.