Associations of pre-diagnosis physical activity with treatment tolerance and treatment efficacy in breast cancer patients with neoadjuvant chemotherapy.

PURPOSE: Higher pre-diagnosis physical activity (PA) is associated with lower all-cause mortality in breast cancer (BCa) patients. However, the association with pathological complete response (pCR) is unclear. We investigated the association between pre-diagnosis PA level and chemotherapy completion, dose delay, and pCR in BCa patients receiving neoadjuvant chemotherapy (NACT). METHODS: 180 stage I-III BCa patients receiving NACT (mean [SD] age of diagnosis: 60.8 [8.8] years) in the Sister Study were included. Self-reported recreational and total PA levels were converted to metabolic equivalent of task-hours per week (MET-hrs/wk). The pCR was defined as no invasive or in situ residual in breast or lymph node (ypT0 ypN0). Multivariable logistic regression analyses estimated odds ratios (ORs) and 95% confidence intervals (CIs) for treatment outcomes. RESULTS: In this sample, 45 (25.0%) BCa patients achieved pCR. Higher pre-diagnosis recreational PA was not associated with lower likelihood of chemotherapy completion (highest vs. lowest tertile: OR = 0.87, 95% CI = 0.30-2.56; Ptrend = 0.84), greater dose delay (OR = 1.45, 95% CI = 0.54-3.92; Ptrend = 0.46), or greater odds of pCR (OR = 1.28, 95% CI = 0.49-3.34; Ptrend = 0.44). Associations were similar for pre-diagnosis total PA. Meeting the recommended level of recreational PA was not associated with pCR overall (≥ 7.5 vs. < 7.5 MET-hrs/wk: OR = 1.33, 95% CI = 0.59-3.01). CONCLUSIONS: Although small sample size and limited information on exercise closer to time of diagnosis limit interpretation, pre-diagnosis PA was not convincingly associated with treatment tolerance or treatment efficacy in BCa patients receiving NACT. Future investigations are needed to better understand the impact of pre-diagnosis PA on BCa treatment.

Syndemic of Substance Abuse, Depression, and Type 2 Diabetes and Their Association with Retention in Care Among People Living with HIV.

Substance abuse (SA), depression, and type 2 diabetes (DM2) often co-occur among people living with HIV (PLHIV). Guided by a syndemic framework, this cross-sectional retrospective study examined the cumulative and interaction effects of SA, depression, and DM2 on retention in HIV care (RIC) among 621 PLHIV receiving medical care in central Pennsylvania. We performed logistic regression analysis to test the associations between SA, depression, and DM2 and RIC. To test the "syndemic" model, we assessed additive and multiplicative interactions. In an unadjusted model, a dose-response pattern between the syndemic index (total number of health conditions) and RIC was detected (OR for 1 syndemic factor vs. none: 1.01, 95% CI: 0.69-1.47; 2 syndemic factors: 1.59, 0.89-2.84; 3 syndemic factors: 1.62, 0.44-5.94), but no group reached statistical significance. Interactions on both additive and multiplicative scales were not significant, demonstrating no syndemic effect of SA, depression, and DM2 on RIC among our study sample. Our findings highlight that comorbid conditions may, in some populations, facilitate RIC rather than act as barriers, which may be due to higher levels of engagement with medical care.

Nicotine Delivery of a Menthol-Flavored Heat-not-Burn Tobacco Product During Directed Use.

INTRODUCTION: IQOS was authorized by the U.S. Food and Drug Administration (FDA) as a modified-risk tobacco product. We conducted a pharmacokinetic study evaluating the nicotine delivery and subjective effects of IQOS use among current menthol cigarette smokers to better understand if IQOS is an acceptable cigarette alternative in light of the proposed menthol cigarette ban. AIMS AND METHODS: Participants were adult smokers of >4 menthol cigarettes per day. After 14-hour nicotine abstinence, participants were provided an IQOS device and menthol heatstick to puff every 20 seconds for a total of 14 puffs. Blood samples were collected at baseline and during active use to calculate nicotine boost from baseline to peak concentration. Nicotine withdrawal symptoms were collected before and after IQOS use. In addition, a modified Product Evaluation Scale for IQOS was collected after use. RESULTS: Participants (n = 8) were a mean age of 43.9 years, 63% were female, 88% identified as White, and they smoked a mean of 17.1 menthol cigarettes per day. After IQOS use, the mean nicotine boost obtained was 15.96 ng/mL (SD = 6.91) (range 9.31 to 30.55 ng/mL). Most (75%) participants reported enjoying use of the product "a lot" or greater and more than half (62.5%) reported reduced cigarette cravings. Most participants reported no side effects after use; however, two experienced dry mouth, three experienced dizziness, one experienced throat irritation, and one experienced headache. CONCLUSION: We found that directed use (14 puffs) of menthol IQOS delivered a mean nicotine boost of 15.96 ng/mL which reduced craving for a cigarette. The majority of participants enjoyed use of IQOS and reported mild side effects. IMPLICATIONS: Menthol IQOS delivered a sufficient dose of nicotine perceived as satisfying by menthol cigarette smokers and it reduced craving with mild side effects. Menthol IQOS has potential to serve as a less harmful alternative for menthol cigarette smokers. The availability of modified risk products like IQOS should be considered by FDA's Comprehensive Plan for Tobacco and Nicotine Regulation.

A Comparison of Mental Health Symptoms among Adults Who Vape Nicotine, Cannabis, or Both.

OBJECTIVES: Dual use of combustible cannabis and nicotine is related to worse mental health symptoms (MHS); however, little is known about MHS among those who vape cannabis and nicotine. The current study aimed to determine if dual use of cannabis and nicotine vapes is associated with worse MHS compared to single use and to identify correlates of MHS for dual users. METHODS: We used Amazon Mechanical Turk to survey adults (N = 492) who used nicotine or cannabis vapes in the past 30 days on stress, anxiety, depression, vape use behaviors and sociodemographic information. We conducted hierarchical linear regressions to compare MHS between dual vs. single substance vape use and to identify correlates of MHS, including sociodemographic variables and vape use characteristics. RESULTS: The final sample was 37.6% female, 87.6% White, and 11% Hispanic/Latinx with a mean age of 34.15 years. After controlling for sociodemographic characteristics and combustible product use, dual users had significantly higher mean MHS severity than single users. For dual users, younger age and being married were associated with higher symptoms of depression and stress. Holding a medical cannabis card was associated with higher anxiety symptoms. CONCLUSION: The findings suggest that dual use of cannabis and nicotine vapes is associated with worse MHS severity compared to single substance use.

A Comparison of Vaping Behavior, Perceptions, and Dependence among Individuals Who Vape Nicotine, Cannabis, or Both.

Background: Electronic delivery systems (e.g., vapes, e-cigarettes) are now popular modes of cannabis and nicotine administration that are often used by the same individuals; however, we still know little about dual nicotine and cannabis vaping. Materials & Methods: An online convenience sample of adult nicotine and/or cannabis vape users residing in the United States completed a 60 min survey on sociodemographic characteristics, cannabis and/or nicotine vape use behaviors and dependence, reasons for vape use, and perceptions of benefits and harms. After data cleaning, we compared dual vs. nicotine-only and cannabis-only vape users with univariate statistics and step-wise hierarchical linear regression analyses. Additionally, we assessed the factor structure, internal consistency, and criterion and convergent validity of the Penn State Cannabis Vaping Dependence Index (PSCVDI). Results: The final sample included 357 dual, 40 cannabis, and 106 nicotine vape users. Compared to nicotine- and cannabis-only vapers, dual vapers started using their nicotine and cannabis vapes at a younger age (p < 0.001), used them for more years (p < 0.001), and were less likely to use their nicotine vape to replace combustible cigarettes (p = 0.047). Dual users vs. single-substance users did not have significantly higher nicotine or cannabis vape dependence scores after controlling for sociodemographic and use behaviors. The PSCVDI showed adequate validity for measuring cannabis vape dependence. Conclusions: This survey is the first to highlight important differences in vape use behaviors and reasons for use between dual vs. cannabis- and nicotine-only vape users.

Effect of menthol on nicotine reduction: Pooled results from two double-blind randomized controlled trials.

BACKGROUND: Menthol upregulates nicotinic acetylcholine receptors and is associated with tobacco dependence. The effects of menthol when smoking cigarettes with varying low nicotine content up to 98 % (e.g., non-addicting) less than commercial cigarettes is not well understood. The U.S. Food and Drug Administration is considering two tobacco product standards in cigarettes including banning menthol and reducing nicotine content. These new standards have the potential to significantly reduce smoking initiation and maintenance by limiting the mechanistic effects of nicotine and menthol on the brain. METHODS: We conducted two parallel randomized clinical trials of gradually reduced nicotine in cigarettes from 11.6 mg down to 0.2 mg nicotine/cigarette (very low nicotine content; VLNC) vs. usual nicotine content (11.6 mg; UNC) over an 18-week period in people who smoke cigarettes with low socioeconomic status (SES) and mental health conditions. RESULTS: Compared to UNC, VLNC was associated with significant reductions in cotinine, cigarettes per day, expired carbon monoxide levels, nicotine dependence and symptomology. These associations did not differ between menthol and non-menthol cigarettes, except people who smoke menthol cigarettes had less of a cotinine reduction in the SES trial. The pooled odds ratio of being adherent with using only VLNC study cigarettes in the gradual nicotine reduction arm for people who smoke non-menthol vs. menthol cigarettes was 2.6 (95 % CI:1.0, 6.4; p-value: 0.04). CONCLUSIONS: When nicotine is lowered to non-addicting levels, the results indicate an independent effect of menthol on the need to sustain nicotine intake in addicted people who smoke cigarettes.

Intentions and Attempts to Quit JUUL E-Cigarette Use: The Role of Perceived Harm and Addiction.

INTRODUCTION: Research on electronic cigarette (e-cigarette) quit intentions and attempts is limited despite the potential health benefits of quitting, especially for long-term users. The current study aimed to investigate perceptions of harm and addictiveness and tobacco use characteristics associated with quit variables among users of a popular e-cigarette brand, JUUL. METHODS: We surveyed 301 US adult JUUL users on their tobacco use characteristics, perceptions of JUUL harm and addictiveness, and quit variables at 3 time points, from July 2019 to April 2020. We used logistic regression models to assess demographic characteristics, smoking characteristics, and perceptions of JUUL harm and addictiveness as correlates of e-cigarette quit intentions, attempts, importance, and confidence. RESULTS: Twenty-three percent of the sample had intentions to quit using JUUL within the year, and 22.6% reported making a lifetime quit attempt. The average rating of quit importance was 4.1 and quit confidence was 5.8 on a Likert scale of 1 to 10. More than 90% of the sample indicated that JUUL was at least moderately addictive, whereas less than one-quarter indicated that JUUL was as harmful or more harmful than smoking. Higher levels of perceived JUUL addictiveness were associated with more quit intentions, attempts, and importance. Higher levels of perceived JUUL harm compared with smoking were associated with more quit importance. CONCLUSION: Our findings suggest that a small proportion of adult JUUL users are interested in quitting. Self-reported perceptions of JUUL's addiction potential may be related to more quit attempts. Findings highlight the need for evidence-based information on e-cigarette addictiveness and effective strategies for cessation.

Evidence from an fMRI study that dessert-flavored e-cigarettes engage taste-related, but not smoking-related, brain circuitry for female daily smokers.

Regulations limiting the sale of flavored e-cigarette products are controversial for their potential to interfere with e-cigarette use as a cessation aid in addition to curbing youth use. Limited research suggests that flavor might enhance the addictive potential of e-cigarettes; however, the acute effects of flavored aerosols on brain function among humans have not been assessed. The present study aimed to isolate and compare the neural substrates of flavored and unflavored e-cigarette aerosols on brain function among nine female daily smokers. Participants inhaled aerosolized e-liquid with 36 mg/mL of nicotine with and without a strawberry-vanilla flavor while undergoing functional magnetic resonance imaging. We used general linear modeling to compare whole-brain mean neural activation and seed-to-voxel task-based functional connectivity between the flavored and unflavored inhalation runs. Contrary to our hypothesis, the flavored aerosol was associated with weaker activation than the unflavored aerosol in the brain stem and bilateral parietal-temporal-occipital region of the cortex. Instead, the flavor engaged taste-related brain regions while suppressing activation of the neural circuits typically engaged during smoking and nicotine administration. Alternatively, functional connectivity between subcortical dopaminergic brain seeds and cortical brain regions involved in motivation and reward salience were stronger during the flavored compared to unflavored aerosol run. The findings suggest that fruity and dessert-flavored e-cigarettes may dampen the reward experience of aerosol inhalation for smokers who initiate e-cigarette use by inhibiting activation of dopaminergic brain circuits. These preliminary findings may have implications for understanding how regulations on flavored e-cigarettes might impact their use as cessation aids. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Characterizing nicotine exposure among a community sample of non-daily smokers in the United States.

BACKGROUND: Over one-quarter of all smokers in the United States identify as non-daily smokers and this number is projected to rise. Unlike daily smokers who typically maintain consistent levels of nicotine exposure with regular smoking, non-daily smokers have variable patterns of smoking that likely result in high intraindividual variability in nicotine intake. The current study aimed to characterize the weekly intraindividual variability in cotinine and identify smoking-related predictors in nondaily smokers. METHODS: An ecological momentary assessment of 60 non-daily smokers ages 24-57 years was conducted over a consecutive 7-day at-home protocol to log each smoking session, assessments of mood and social activity during smoking, and collection of daily saliva samples in a convenience sample from Pennsylvania, USA. Hierarchical linear regression analyses were conducted to determine the effects of smoking characteristics on total cotinine exposure measured by pharmacokinetic area under the curve and the range, maximum, and minimum cotinine values during the week controlling for demographic variables. RESULTS: The mean daily cotinine level was 119.2 ng/ml (SD = 168.9) with individual values that ranged from nondetectable to 949.6 ng/ml. Menthol predicted increased total cotinine levels (P < 0.05). Shorter time to the first cigarette of the day predicted significantly higher minimum (P < 0.05), maximum (P < 0.05), and total cotinine values (P < 0.05) after controlling for covariates. Negative emotions and social interactions with others were also significantly associated with higher cotinine metrics. There was no significant effect of the nicotine metabolite ratio. CONCLUSIONS: Our findings highlight the variability in nicotine exposure across days among non-daily smokers and point to the role of smoking context in nicotine exposure. The findings suggest the need to develop better assessment methods to determine health and dependence risk and personalized cessation interventions for this heterogeneous and growing group of smokers.

Hypoactivation in the precuneus and posterior cingulate cortex during ambiguous decision making in individuals with HIV.

People with human immunodeficiency virus (HIV) often have neurocognitive impairment. People with HIV make riskier decisions when the outcome probabilities are known, and have abnormal neural architecture underlying risky decision making. However, ambiguous decision making, when the outcome probabilities are unknown, is more common in daily life, but the neural architecture underlying ambiguous decision making in people with HIV is unknown. Eighteen people with HIV and 20 controls completed a decision making task while undergoing functional magnetic resonance imaging scanning. Participants chose between a certain reward and uncertain reward with a known (risky) or unknown (ambiguous) probability of winning. There were three levels of risk: high, medium, and low. Ambiguous > risky brain activity was compared between groups. Ambiguous > risky brain activity was correlated with emotional/psychiatric functioning in people with HIV. Both groups were similarly ambiguity-averse. People with HIV were more risk-averse than controls and chose the high-risk uncertain option less often. People with HIV had hypoactivity in the precuneus, posterior cingulate cortex (PCC), and fusiform gyrus during ambiguous > medium risk decision making. Ambiguous > medium risk brain activity was negatively correlated with emotional/psychiatric functioning in individuals with HIV. To make ambiguous decisions, people with HIV underrecruit key regions of the default mode network, which are thought to integrate internally and externally derived information to come to a decision. These regions and related cognitive processes may be candidates for interventions to improve decision-making outcomes in people with HIV.

Tobacco Use Changes and Perceived Health Risks among Current Tobacco Users during the COVID-19 Pandemic.

COVID-19 has become a global pandemic, with over 81 million cases worldwide. To assess changes in tobacco use as a result of the pandemic, we surveyed a convenience sample of current tobacco users between April and June 2020. The sample was taken from a tobacco user research registry (n = 3396) from the Penn State College of Medicine in Hershey, Pennsylvania, USA. Participants who responded to the survey and were eligible for this study (n = 291) were 25.6% male, 93% white, and had a mean age of 47.3 (SD = 11.6) years. There were no reports of participants testing positive for COVID-19, but 21.7% reported experiencing symptoms associated with the virus. Most participants (67%) believed that their risk of contracting COVID-19 was the same as non-tobacco users, but 57.7% believed that their risk of serious complications, if infected, was greater compared to non-tobacco users. A total of 28% reported increasing their cigarette use during the pandemic. The most common reasons for increased use were increased stress, more time at home, and boredom while quarantined. Nearly 15% reported decreasing their tobacco use. The most common reasons for reduced use were health concerns and more time around non-smokers (including children). A total of 71 (24.5%) users reported making a quit attempt. Characterizing these pandemic-related changes in tobacco use may be important to understanding the full scope of subsequent health outcomes resulting from the pandemic. Tobacco cessation resources should be tailored to allow for safe, appropriate access for those interested in quitting.

COVID-19 Vaccination Uptake and Hesitancy Among Current Tobacco Users.

Novel mRNA vaccines have been developed and were first distributed to high-risk individuals (including smokers) in the United States starting in December 2020 to combat the coronavirus (COVID-19) pandemic. Over one-half of the U.S. adult population has received at least 1 dose of a COVID-19 vaccine, but many others have reported hesitation about becoming vaccinated. We examined COVID-19 vaccine uptake and hesitancy from a convenience sample of Pennsylvanian adult smokers in April 2021, approximately 3 months after tobacco users were eligible to receive vaccination in the state. Participants (n = 231) were 23.4% male, 90.5% white, and had a mean age of 48.1 (SD = 11.9) years. All participants were current tobacco users, with the majority reporting current cigarette smoking (90.9%) with an average of 16 (SD = 8.1) cigarettes smoked per day. Nearly 60% (n = 137) reported receiving at least 1 dose of the vaccine and of those who did not (n = 94), 84% (n = 79) said they were somewhat or very unlikely to get a vaccine. Those who were unvaccinated were more likely to not consume news about COVID-19 (chi-square P-value < .01) and less likely to believe government news sources as reliable information for COVID-19 (chi-square P-value < .01). Qualitative responses among those who were vaccine hesitant expressed concerns about the lack of research on the vaccine, distrust of the safety of the vaccine, and fears about side effects. Understanding vaccine hesitancy among tobacco users can help develop targeted communication strategies and directly address concerns to promote vaccination among this population who may be at an increased risk of severe complications from COVID-19.

Dependence and Use Characteristics of Adult JUUL Electronic Cigarette Users.

BACKGROUND: JUUL is a popular electronic cigarette (e-cig) that is capable of delivering nicotine similarly to a cigarette. While known to deliver high doses of nicotine, there is little systematic evidence to show how the nicotine delivery of JUUL translates to user dependence. Purpose: The purpose of the study was to evaluate self-reported dependence of JUUL users and examine the relationship of dependence to user behaviors. Methods: Current JUUL users were recruited via Amazon Mechanical Turk to complete an online survey about their use of JUUL. Participants were asked to complete the Penn State Electronic Cigarette Dependence Index (PSECDI) and to answer questions about their use patterns and other tobacco use. Means and frequencies were used to describe the sample. A linear regression model was used to predict user dependence. Results: Participants (n = 76) were 65.4% male with a mean age of 31.9 (SD = 8.3) years. The mean PSECDI score was 7.8 (SD = 4.2) and ranged from no (15.8%) to high (14.5%) dependence. Overall predictors of a greater PSECDI score included reporting ever stealth vaping (ß = 2.8, p < .01) and reporting greater use days in the past 30 (ß = 3.5, p < .01). Conclusions: On average, JUUL users reported low to medium nicotine dependence on the PSECDI. JUUL user dependence may be more similar to e-cig user dependence than cigarette smoker dependence. These preliminary findings should be followed up in studies of larger samples of Juul users, collecting multiple measures of dependence, as well as biomarkers of nicotine intake (e.g. cotinine).

An Electronic Aerosol Delivery System for Functional Magnetic Resonance Imaging.

BACKGROUND: Public health concerns over the addictive potential of electronic cigarettes (e-cigs) have heightened in recent years. Brain function during e-cig use could provide an objective measure of the addictive potential of new vaping products to facilitate research; however, there are limited methods for delivering e-cig aerosols during functional magnetic resonance imaging (fMRI). The current study describes the development and feasibility testing of a prototype to deliver up to four different e-cig aerosols during fMRI. METHODS: Standardized methods were used to test the devices' air flow variability, nicotine yield, and free radical production. MRI scans were run with and without the device present to assess its safety and effects on MRI data quality. Five daily smokers were recruited to assess plasma nicotine absorption from e-liquids containing nicotine concentrations of 8, 11, 16, 24, and 36 mg/ml. Feedback was collected from participants through a semi-structured interview and computerized questionnaire to assess comfort and subjective experiences of inhaling aerosol from the device. RESULTS: Nicotine yield captured from the aerosol produced by the device was highly correlated with the nicotine concentration of the e-liquids used (R2 = 0.965). Nicotine yield was reduced by a mean of 48% and free radical production by 17% after traveling through the device. The e-liquid containing the highest nicotine concentration tested (36 mg/ml) resulted in the highest plasma nicotine boost (6.6 ng/ml). Overall, participants reported that the device was comfortable to use and inhaling the e-cig aerosols was tolerable. The device was determined to be safe for use during fMRI and had insignificant effects on scan quality. CONCLUSIONS: With the current project, we were able to design a working prototype that safely and effectively delivers e-cig aerosols during fMRI. The device has the potential to be used to assess brain activation during e-cig use and to compare brain reactivity to varying flavors, nicotine concentrations, and other e-cig characteristics.

Response to Flavored Cartridge/Pod-Based Product Ban among Adult JUUL Users: "You Get Nicotine However You Can Get It".

In order to curb increasing youth electronic cigarette (e-cig) use, the United States Food and Drug Administration (FDA) banned the sale of flavored cartridge/pod-based products in February 2020. This mixed-methods study aimed to evaluate the impact of the FDA ban on adult JUUL users. The samples of current adult JUUL users were surveyed via Amazon Mechanical Turk at three time-points n = 76 (Sample 1); n = 128 (Sample 2); n = 86 (Sample 3) before and after the FDA flavored/pod ban. The participants were asked to report the JUUL flavored pod used most often and answer questions on purchasing generic pods or refilling (Quantitative). JUUL users were then interviewed in order to explore their perceptions and behaviors related to the FDA ban of flavored cartridge/pod-based products (Qualitative; n = 16). Quantitative data analysis evaluated the differences in variables by time-point. Qualitative data were coded into themes while using the constant comparative method. We found a significant decrease in the use of mint pods (43.4%, 22.7%, 16.3%) (p < 0.01), while there was a significant increase in the use of menthol pods (6.6%, 26.6%, 37.2%) (p < 0.01). Themes that emerged from the qualitative data included switching from mint to menthol pods, refilling pods, and switching to other products that are available in the desired flavors, such as generic pods or disposable e-cigs. Future research is needed in order to evaluate the impact of these behaviors on public health.

Nicotine absorption during electronic cigarette use among regular users.

BACKGROUND: The capability of electronic cigarette devices (e-cigs) to deliver nicotine is key to their potential to replace combustible cigarettes. We compared nicotine delivery and subjective effects associated with the use of two classes of e-cigarettes and cigarettes. METHODS: 14 e-cigarette users were instructed to vape their own e-cigarette device every 20 seconds for 10 minutes while blood was drawn at 1, 2, 4, 6, 8, 10,12, and 15 minutes after initiating vaping. Users rated withdrawal symptoms and side effects before and after vaping. E-cigarette devices were classified as first-generation (same size as cigarette, no activation button) or advanced (larger than cigarette with an activation button). Separately, 10 cigarette smokers completed a similar protocol. Fisher's Exact Test and two-sided t-tests were used as appropriate to determine differences in outcomes between first-generation e-cigarette users, advanced e-cigarette users, and smokers. RESULTS: Compared to first-generation devices, advanced devices were associated with greater serum nicotine Cmax (ng/ml) (11.5 v. 2.8, p = 0.0231) and greater nicotine boost (ng/ml) (10.8 v. 1.8, p = 0.0177). Overall, e-cigarettes users experienced a significant reduction in withdrawal and craving, although there were no significant differences between users of first-generation and advanced devices. Comparing e-cigarettes overall to cigarettes, cigarettes were associated with greater Cmax (25.9 v. 9.0, p = 0.0043) and greater nicotine boost (21.0 v. 8.2, p = 0.0128). CONCLUSIONS: Advanced e-cigarettes delivered significantly more nicotine than first-generation devices but less than combustible cigarettes. Overall, e-cigarette use was associated with a reduction in withdrawal and craving with no reported side effects. The wide variation in nicotine absorption from different e-cigarette devices should be considered in studies of e-cigarettes for smoking cessation.

Reward and executive control network resting-state functional connectivity is associated with impulsivity during reward-based decision making for cocaine users.

BACKGROUND: Cocaine addiction is related to impulsive decision making that is mediated by brain circuitry involved in reward processing and executive functions, such as cognitive control and attentional salience. Resting-state functional connectivity between reward and executive control circuitry is altered among cocaine users, with concomitant deficits in impulsivity and learning. Prior research has examined how select brain regions interact to influence impulsive decision making for drug users; however, research examining interactions between large-scale brain networks and impulsive behavior is limited. METHODS: The current study compared reward and executive control network resting-state functional connectivity and its relationship to impulsive decision making between cocaine users (n = 37) and non-cocaine using control participants (n = 35). Participants completed computerized decision-making tasks and a separate resting-state functional magnetic resonance imaging scan. Data underwent independent component, dual regression, and linear regression moderation analyses. RESULTS: Higher impulsivity on the Balloon Analogue Risk Task (BART) was associated with inverse resting-state connectivity between the left cognitive control and subgenual anterior cingulate extended reward networks for cocaine users, while the opposite was found for controls. Less impulsivity on the monetary choice questionnaire was associated with stronger positive resting-state connectivity between the attentional salience and striatal core reward networks for controls, while cocaine users showed no association between impulsivity and resting-state connectivity of these networks. CONCLUSIONS: Cocaine users show aberrant associations between reward-executive control resting-state network coupling and impulsive decision making. The findings support the conclusion that an imbalance between reward and executive control circuitry contributes to impulsivity in drug use.

Synergistic effects of marijuana abuse and HIV infection on neural activation during a cognitive interference task.

Marijuana use, which is disproportionately prevalent among human immunodeficiency virus (HIV)-infected persons, can alter activity in fronto-parietal regions during cognitively demanding tasks. While HIV is also associated with altered neural activation, it is not known how marijuana may further affect brain function in this population. Our study examined the independent and additive effects of HIV infection and regular marijuana use on neural activation during a cognitive interference task. The sample included 93 adults who differed on marijuana (MJ) and HIV statuses (20 MJ+/HIV+, 19 MJ+/HIV-, 29 MJ-/HIV+, 25 MJ-/HIV-). Participants completed a counting Stroop task during a functional magnetic resonance imaging scan. Main and interactive effects on neural activation during interference versus neutral blocks were examined using a mixed-effects analysis. The sample showed the expected Stroop effect for both speed and accuracy. There were main effects of MJ in the right and left inferior parietal lobules, with the left cluster extending into the posterior middle temporal gyrus and a main effect of HIV in the dorsal anterior cingulate cortex. There was an interaction in the left fronto-insular cortex, such that the MJ+/HIV+ group had the largest increase in activation compared with other groups. Among MJ+, signal change in this cluster correlated positively with cumulative years of regular marijuana use. These results suggest that comorbid HIV and marijuana use is associated with complex neural alterations in multiple brain regions during cognitive interference. Follow-up research is needed to determine how marijuana-related characteristics may moderate HIV neurologic disease and impact real-world functioning.

Income as a moderator of psychological stress and nicotine dependence among adult smokers.

BACKGROUND: Perceived stress and psychological distress are associated with more cigarette craving and withdrawal, higher nicotine dependence, and less success during quit attempts. Low income smokers have disproportionately higher rates of smoking and may be particularly vulnerable to the effects of stress on smoking dependence. The aim of the current study was to assess if lower income smokers have a stronger association between stress and nicotine dependence than higher income smokers. METHODS: Data were obtained from the Pennsylvania Adult Smoking Study, which included 351 daily smokers. Subjects completed PhenX Toolkit and other self-report measures of socioeconomic factors, the 10-item Perceived Stress Scale, Kessler Psychological Distress Scale (K6), Fagerstrom Test for Nicotine Dependence (FTND), and the Hooked on Nicotine Checklist (HONC). Moderation analyses using linear regression examined income-related differences in the association between stress and nicotine dependence. RESULTS: Income groups were categorized by an annual household income of $50,000 based on visual-inspection of scatter plots of income by nicotine dependence. Compared to higher income smokers, lower income smokers had significantly higher mean levels of nicotine dependence on the FTND [3.74 vs. 4.79, p < 0.001], perceived stress [15.63 vs. 17.95, p = 0.004], and psychological distress [5.30 vs. 6.86, p = 0.001], respectively. There were interaction effects, such that lower income smokers had a strong, positive associations between FTND and perceived stress (B = -0.11, CI = -0.17 to -0.04, p = 0.002) and psychological distress (B = -0.13, CI = -0.25 to -0.02, p = 0.022) whereas no association was found in higher income smokers. No significant moderation effects were found for the HONC or when income groups were categorized by U.S. federal poverty level. CONCLUSIONS: The results highlight that the relationship between increasing stress and FTND was found in lower but not higher income groups. Future research should examine socioeconomic, environmental and psychosocial factors that may facilitate increased smoking during stress-induced craving.