E-Cigarette Nicotine Delivery Among Young Adults by Nicotine Form, Concentration, and Flavor: A Crossover Randomized Clinical Trial.

Importance: Concerns have been raised about the abuse liability of modern e-cigarettes that use acidic additives to form nicotine salts, making the inhalation of nicotine smoother than freebase nicotine. Objective: To examine the effects of nicotine form and concentration and e-liquid flavor on subjective effects ratings, vaping behavior, and nicotine uptake among young adults who use e-cigarettes. Design, Setting, and Participants: In this single-blind, within-participant, crossover randomized clinical trial, a convenience sample of young adults aged 21 to 25 years who currently used e-cigarettes was recruited from December 2021 to August 2023, for in-person research laboratory visits in Columbus, Ohio. Interventions: Participants completed up to 9 vaping sessions, starting with their usual e-cigarette brand in the first session followed by 1 of 8 laboratory-prepared e-liquids in a randomly assigned order in each subsequent session. Prepared e-liquids varied by nicotine form (salt-based vs freebase), nicotine concentration (5% vs 1% weight per weight), and flavor (menthol vs tobacco). Each session included a 5-minute, 10-puff standardized vaping period followed by 30 minutes of ad libitum vaping. Main Outcomes and Measures: At 4 time points (0, 5, 10, and 35 minutes) during each vaping session, plasma samples were collected for assessing nicotine uptake, and self-reports of urges, craving, and withdrawal were collected via questionnaires. Positive subjective effects were self-reported after 35 minutes of vaping using a visual analog scale; urges and cravings were reported using the Questionnaire of Smoking Urges (QSU). Puff topography data were collected throughout each vaping session. Results: Seventy-two participants (mean [SD] age, 22.4 [1.4] years; 42 [58.3%] female) who sampled at least 1 laboratory-prepared e-liquid composed the analytic sample. Salt-based (vs freebase) nicotine e-liquids increased nicotine intake, with 5% salt-based e-liquids delivering the highest mean plasma levels of nicotine (11.2 ng/mL [95% CI, 9.3-13.2 ng/mL] at 5 minutes; 17.2 ng/mL [95% CI, 14.3-20.1 ng/mL] at 35 minutes) irrespective of flavors. Higher positive subjective effect ratings (eg, for liking) were received by salt-based (42.8; 95% CI, 39.4-46.1) vs freebase (32.0; 95% CI, 28.6-35.3) nicotine, 1% (43.4; 95% CI, 40.2-46.6) vs 5% (31.2; 95% CI, 27.7-34.6) nicotine, and menthol-flavored (43.2; 95% CI, 39.7-46.7) vs tobacco-flavored (31.5; 95% CI, 28.4-34.7) e-liquids. Salt-based and 1% but not menthol-flavored nicotine elicited more intense puffing (eg, 25% [95% CI, 12%-40%] more total puffs for nicotine salts vs freebase). All study e-liquids reduced urges and cravings, with 5% vs 1% nicotine being more effective (mean [SE] QSU-Desire score at 35 minutes, 15.4 [0.5] vs 16.7 [0.5]). Conclusions and Relevance: In this crossover randomized clinical trial among young adult e-cigarette users, salt-based (vs freebase) nicotine e-liquids increased nicotine intake and yielded more positive subjective effects ratings and intense puffing behaviors, suggesting higher abuse potential. Restricting the level of acidic additives and menthol flavoring may reduce the addictiveness of e-cigarettes. Trial Registration: ClinicalTrials.gov Identifier: NCT05458895.

Analysis of combined probability and nonprobability samples: A simulation evaluation and application to a teen smoking behavior survey.

In scientific studies with low-prevalence outcomes, probability sampling may be supplemented by nonprobability sampling to boost the sample size of desired subpopulation while remaining representative to the entire study population. To utilize both probability and nonprobability samples appropriately, several methods have been proposed in the literature to generate pseudo-weights, including ad-hoc weights, inclusion probability adjusted weights, and propensity score adjusted weights. We empirically compare various weighting strategies via an extensive simulation study, where probability and nonprobability samples are combined. Weight normalization and raking adjustment are also considered. Our simulation results suggest that the unity weight method (with weight normalization) and the inclusion probability adjusted weight method yield very good overall performance. This work is motivated by the Buckeye Teen Health Study, which examines risk factors for the initiation of smoking among teenage males in Ohio. To address the low response rate in the initial probability sample and low prevalence of smokers in the target population, a small convenience sample was collected as a supplement. Our proposed method yields estimates very close to the ones from the analysis using only the probability sample and enjoys the additional benefit of being able to track more teens with risky behaviors through follow-ups.

An Improved Assessment Method to Estimate (Poly)phenol Intake in Adults with Chronic Pancreatitis.

BACKGROUND: Insights into (poly)phenol exposure represent a modifiable factor that may modulate inflammation in chronic pancreatitis (CP), yet intake is poorly characterized and methods for assessment are underdeveloped. AIMS: The aims are to develop and test a method for estimating (poly)phenol intake from a 90-day food frequency questionnaire (FFQ) using the Phenol-Explorer database and determine associations with dietary patterns in CP patients versus controls via analysis of previously collected cross-sectional data. METHODS: Fifty-two CP patients and 48 controls were recruited from an ambulatory clinic at a large, academic institution. To assess the feasibility of the proposed methodology for estimating dietary (poly)phenol exposure, a retrospective analysis of FFQ data was completed. Mann-Whitney U tests were used to compare (poly)phenol intake by group; Spearman correlations and multivariable-adjusted log-linear associations were used to compare (poly)phenol intakes with dietary scores within the sample. RESULTS: Estimation of (poly)phenol intake from FFQs was feasible and produced estimates within a range of intake previously reported. Total (poly)phenol intake was significantly lower in CP vs controls (463 vs. 567mg/1000kcal; p = 0.041). In adjusted analyses, higher total (poly)phenol intake was associated with higher HEI-2015 (r = 0.34, p < 0.001), aMED (r = 0.22, p = 0.007), EDIH (r = 0.29, p < 0.001), and EDIP scores (r = 0.35, p < 0.001), representing higher overall diet quality and lower insulinemic and anti-inflammatory dietary potentials, respectively. CONCLUSIONS: Using enhanced methods to derive total (poly)phenol intake from an FFQ is feasible. Those with CP have lower total (poly)phenol intake and less favorable dietary pattern indices, thus supporting future tailored dietary intervention studies in this population.

An observational human laboratory assessment of nicotine delivery, vaping topography and subjective effects of usual brand electronic cigarette use among young adults.

AIMS: To measure nicotine delivery, vaping topography and subjective effects of current generations of disposable, cartridge-based and other types of electronic cigarettes (e-cigarettes) among young adults. DESIGN, SETTING, PARTICIPANTS: Observational, human laboratory assessment of e-cigarette use in Columbus, Ohio, USA (July 2020 to June 2021). Participants (n = 96, 60.4% female, age mean = 21.7 [standard deviation = 1.7] years, 82.4% white race) were identified via their participation in a cohort study or other convenience sampling and were 18 to 25 years old, vaped ≥4 days/week for ≥4 weeks and used other tobacco products for ≤5 days of past 30 days. Participants completed a pre-vaping questionnaire, vaped their usual brand of e-cigarette ad libitum for 30 min and completed a post-vaping questionnaire. MEASUREMENTS: Outcome variables included pre- and post-vaping measures of plasma nicotine (t = 0 and t = 30, respectively) and craving and withdrawal symptoms, as well as vaping topography (e.g. flow rate and inter-puff interval), pre-vaping expectancies and post-vaping product appeal. Variables used to characterize the sample included demographics, e-cigarette and other tobacco use history, e-cigarette dependence and e-cigarette device characteristics (e.g. device type, flavor and nicotine form). FINDINGS: Participants reported moderate nicotine dependence on average via the E-Cigarette Dependence Scale (mean = 6.9 [standard deviation = 4.0]). Following 30 min of ad libitum vaping, participants achieved substantial plasma nicotine boost (mean = 18.8 [standard deviation = 14.5] ng/mL), corresponding with statistically significant decreases in withdrawal symptoms measured via the Minnesota Nicotine Withdrawal Scale (pre-vaping mean = 9.0 [standard deviation = 5.1], post-vaping mean = 4.3 [standard deviation = 3.9]; P-value <0.0001). Pre-vaping, participants reported moderate vaping expectancies (e.g. mean = 2.5 [standard deviation = 1.0] on a scale from 0 to 4 for smell and taste expectancies); post-vaping, participants reported high satisfaction (mean = 4.6 [standard deviation = 1.2] on a scale from 1 to 7) and moderate reward (mean = 2.9 [standard deviation = 1.2]) and respiratory sensations (mean = 3.7 [standard deviation = 1.6]). Nearly half of participants (47.9%) used disposable e-cigarettes, and most used a mint/menthol or fruit flavored (99.0%) and nicotine salt (98.9%) e-liquid. CONCLUSIONS: Among young adults in the United States, the latest generations of e-cigarettes appear to deliver large quantities of nicotine (similar to cigarettes) and significantly relieve withdrawal symptoms, and they are appealing.

Evaluating the Role of Nicotine Stereoisomer on Nicotine Pouch Abuse Liability: A Randomized Crossover Trial.

INTRODUCTION: Many oral nicotine pouch (ONP) brands use synthetic nicotine, which typically contains a racemic (50:50) mixture of nicotine's two stereoisomers: S-nicotine and R-nicotine. Because tobacco-derived nicotine contains more than 99% S-nicotine, the effects of R-nicotine in humans are not well known. We compared systemic nicotine exposure and product appeal of ONPs containing more than 99% S-nicotine versus racemic nicotine. AIMS AND METHODS: N = 18 adult smokers (Mage = 45 years, 66.7% male, 77.8% White) enrolled in a three-visit single-blind, randomized crossover study. During each visit, participants used one wintergreen-flavored, 3 mg nicotine ONP for 30 min following at least12 h nicotine abstinence. Study ONP #1 contained more than 99% S-nicotine and the other two study ONPs contained racemic nicotine (collapsed for analyses). Plasma nicotine assessments and measures of withdrawal relief occurred at t = 0, 5, 15, 30, 60, and 90 min; measures of product appeal were assessed following ONP use. RESULTS: Using the ONP with more than 99% S-nicotine resulted in greater plasma nicotine concentration from 15 to 90 min (p < .0001) and greater maximum plasma nicotine concentration than the ONPs with racemic nicotine (M = 9.9 ng/mL [SD = 2.5] vs. M = 5.7 ng/mL [SD = 2.8], respectively; p < .0001). Product liking and withdrawal relief were similar across ONPs, although participants reported more "bad effects" when using the ONP with more than 99% S-nicotine. CONCLUSIONS: Participants reported few subjective differences in ONPs according to nicotine stereoisomer, but plasma nicotine concentration was greater for ONPs using more than 99% S-nicotine. ONPs with more than 99% S-nicotine (vs. racemic nicotine) might be better substitutes for cigarettes, but research into other ONP characteristics (eg flavors, freebase nicotine) is needed to inform regulation. IMPLICATIONS: Little is known about the effects of racemic (vs. S-) nicotine in humans. In a sample of adults who smoke cigarettes, we identified that oral nicotine pouches containing racemic nicotine exposed participants to less nicotine than oral nicotine pouches containing only S-nicotine, but both types of oral nicotine pouches held similar, moderate appeal. Additional research evaluating the roles that flavorings, total nicotine concentration, and freebase nicotine play in the abuse liability of oral nicotine pouches would inform comprehensive product regulations to support public health.

Physical Activity Decreases Inflammation and Delays the Development of Obesity-Associated Pancreatic Ductal Adenocarcinoma.

Obesity is a risk factor for pancreatic ductal adenocarcinoma (PDAC), a deadly disease with limited preventive strategies. Lifestyle interventions to decrease obesity represent a potential approach to prevent obesity-associated PDAC. In this study, we examined whether decreasing obesity through physical activity (PA) and/or dietary changes could decrease inflammation in humans and prevent obesity-associated PDAC in mice. Comparison of circulating inflammatory-associated cytokines in subjects (overweight and obese) before and after a PA intervention revealed PA lowered systemic inflammatory cytokines. Mice with pancreatic-specific inducible KrasG12D expression were exposed to PA and/or dietary interventions during and after obesity-associated cancer initiation. In mice with concurrent diet-induced obesity and KrasG12D expression, the PA intervention led to lower weight gain, suppressed systemic inflammation, delayed tumor progression, and decreased proinflammatory signals in the adipose tissue. However, these benefits were not as evident when obesity preceded pancreatic KrasG12D expression. Combining PA with diet-induced weight loss (DI-WL) delayed obesity-associated PDAC progression in the genetically engineered mouse model, but neither PA alone nor combined with DI-WL or chemotherapy prevented PDAC tumor growth in orthotopic PDAC models regardless of obesity status. PA led to the upregulation of Il15ra in adipose tissue. Adipose-specific overexpression of Il15 slowed PDAC growth but only in nonobese mice. Overall, our study suggests that PA alone or combined with DI-WL can reduce inflammation and delay obesity-associated PDAC development or progression. Lifestyle interventions that prevent or manage obesity or therapies that target weight loss-related molecular pathways could prevent progression of PDAC. Significance: Physical activity reduces inflammation and induces changes to adipose-related signaling to suppress pancreatic cancer, supporting the potential of obesity management strategies to reduce the risk of developing pancreatic cancer. See related commentary by Sogunro and Muzumdar, p. 2935.

Examining the Predictive Utility of Behavioral Economic Demand Indices and Subjective Effects on the Actualized Reinforcing Value of Menthol Cigarettes and Potential Alternatives.

INTRODUCTION: Considering recent and proposed bans on menthol cigarettes, methods are needed to understand the substitutability of potential menthol cigarette alternatives (MCAs) for menthol cigarettes. This study examined the prospective relationship between behavioral economic demand indices and subjective effects of usual brand menthol cigarettes (UBMC) and preferred MCAs with subsequent performance on a laboratory-based concurrent-choice task comparing UBMC and MCAs. METHODS: Eighty participants who typically smoked menthol cigarettes completed this clinical laboratory study. After sampling each product, participants completed the cigarette purchase task (CPT) and modified cigarette evaluation questionnaire (mCEQ). Following 1 week of substituting their preferred MCA for their UBMC, participants completed a 90-minute concurrent-choice self-administration (SA) task comparing their UBMC and preferred MCA. Linear regression models explored associations between CPT demand indices and mCEQ subjective effects in the laboratory with subsequent response effort for UBMCs on the concurrent-choice task. RESULTS: Three demand indices for UBMC were positively associated with UBMC response effort: essential value (EV; p = .02), Omax (p = .02), and breakpoint (p = .04). Four CPT demand indices for the preferred MCA significantly corresponded with UBMC response effort: EV (p = .03), price associated with maximal expenditure (Pmax) (p = .04), maximal expenditure (Omax) (p = .03), and breakpoint (p = .03). Subjective effects captured by the mCEQ were not associated with response effort. CONCLUSIONS: Demand indices reflecting Persistence (ie, sensitivity to escalating price) predicted effort to obtain UBMC puffs on the concurrent-choice task. Among this sample, the CPT captured information on the relative reinforcing value (ie, addiction potential) of combustible tobacco products similar to the longer SA task. IMPLICATIONS: In an ever-changing product market, assessing the reinforcing efficacy of menthol cigarettes and putative substitutes quickly and with validity is an important methodological tool for understanding abuse liability. Results suggest that behavioral economic demand indices of CPT efficiently capture information on the relative reinforcing value of UBMC and plausible alternative tobacco products, similar to a 90-minute in-laboratory SA task.

The impact of bariatric surgery on admissions for gastrointestinal complications and conditions associated with obesity: A nationwide study.

BACKGROUND: Obesity worsens various gastrointestinal pathologies. While bariatric surgery ameliorates obesity, it substantially modifies the gastrointestinal system depending on surgery type, with limited data on subsequent impact on obesity-related gastrointestinal admissions. METHODS: Using the 2012-2014 Nationwide Readmission Database, we included individuals with obesity who received vertical sleeve gastrectomy (VSG), Roux-en-Y gastric bypass (RYGB), or hernia repair (HR-control surgery). Our main focus was the adjusted odds ratio (aOR) for gastrointestinal inpatient admissions within 6 months following surgery compared to the 6 months preceding it, while controlling for several confounding factors. Gastrointestinal admissions were grouped into postoperative complications or obesity-associated gastrointestinal conditions. RESULTS: Our cohort included 140,103 adults with RYGB, 132,253 with VSG, and 12,436 HR controls. Postoperative gastrointestinal complications were most common after RYGB, prominently obstruction (aOR = 33.17, 95%CI: 18.01, 61.10), and Clostridium difficile infection (aOR: 12.52, 95%CI: 6.22, 25.19). VSG also saw significantly increased but less frequent similar conditions. Notably, for gastrointestinal conditions associated with obesity, acute pancreatitis risk was higher post-VSG (aOR = 6.26, 95%CI: 4.02, 9.73). Post-RYGB patients were most likely to be admitted for cholelithiasis with cholecystitis (aOR: 4.15, 95% CI: 3.24, 5.31), followed by chronic liver disease (aOR: 3.00, 95% CI: 2.33, 3.87). The risk of noninfectious colitis admissions was threefold higher after RYGB and VSG. No gastrointestinal conditions showed an increase after HR. CONCLUSION: Despite weight loss, bariatric surgery was associated with an increased risk of hepato-pancreatobiliary and colitis admissions related to obesity in the first six postoperative months, with considerable variations in rates of gastrointestinal conditions by surgery type.

Identifying Novel Motivation Phase-Specific Cessation Targets for Youth Experiencing Homelessness in the United States.

INTRODUCTION: Of youth experiencing homelessness (YEH; 14-24 years old), 70%+ smoke combustible, commercial tobacco. Though many have tried to quit, most use ineffective methods. Drop-in centers for YEH are opportune places to link YEH to evidence-based treatment. Using the Phase-Based Model (PBM) for Cessation Research, the aim of this study was to identify "Motivation" phase-specific challenges impacting YEH's willingness to make a quit attempt-the goal of this cessation phase. AIMS AND METHODS: Surveys were interview administered with 96 past-week combusted tobacco users accessing drop-in services. Regression models were fit to confirm hypothesized challenges impacting YEH's willingness to quit. RESULTS: Moderate nicotine dependence was noted-a key Motivation phase cessation mechanism targeted-and was associated with population challenges including, but not limited to, replacing food with tobacco, accidental oxygen-deprivation events, and smoking to socialize. While 67.1% of participants made a past-year quit attempt, 45.8% expressed 30-day quit interest. Dimensions of coping with housing were associated with quit attempts and quit interest. Quit attempts were also associated with nicotine dependence, working, and smoking to socialize. Whereas, quit interest was associated with less endorsement of smoking to regulate affect and more endorsement to avoid danger. CONCLUSIONS: Though common challenges targeted in Motivation phase cessation exist among YEH, other challenges may also need to be addressed to promote quitting. IMPLICATIONS: Future research in optimizing evidence-based cessation access for YEH through drop-in centers may consider addressing the challenges of housing, food security, social context, violence, and neurotrauma sequela to bolster YEH willingness to make a quit attempt.

Evaluating the effects of nicotine concentration on the appeal and nicotine delivery of oral nicotine pouches among rural and Appalachian adults who smoke cigarettes: A randomized cross-over study.

BACKGROUND AND AIMS: Oral nicotine pouches (ONPs) probably offer reduced harm compared with cigarettes, but independent data concerning their misuse liability are lacking. We compared nicotine delivery and craving relief from ONPs with different nicotine concentrations to cigarettes. DESIGN: This was a single-blind, three-visit (≥ 48-hour washout), randomized-cross-over study. Participants were encouraged to complete all study visits in less than 1 month. SETTING: The study took place in Rural/Appalachian Ohio. PARTICIPANTS: Participants comprised 30 adults who smoke cigarettes. Participants (meanage = 34.5) were 60% men and 90% White. INTERVENTION: Participants who were ≥ 12-hour tobacco-abstinent used: (1) a 3-mg nicotine concentration ONP, (2) a 6-mg nicotine concentration ONP and (3) usual brand cigarette in separate visits. ONPs (wintergreen Zyn) were used for 30 minutes; cigarettes were puffed every 30 sec for 5 minutes. MEASUREMENTS: Plasma nicotine and self-reported craving were assessed at t = 0, 5, 15, 30, 60 and 90 minutes. The primary outcome was plasma nicotine concentration at t = 30 minutes. A secondary outcome was craving relief at t = 5 minutes. FINDINGS: At t = 30, mean [95% confidence interval (CI)] plasma nicotine was 9.5 ng/ml (95% CI = 7.1, 11.9 ng/ml) for the 3 mg nicotine ONP, 17.5 ng/ml (95% CI = 13.7, 21.3) for the 6 mg nicotine ONP and 11.4 ng/ml (95% CI = 9.2, 13.6 ng/ml) for the cigarette. Mean plasma nicotine at t = 30 minutes differed between the 3- and 6-mg nicotine ONPs (P = 0.001) and between the 6-mg nicotine ONP and cigarette (P = 0.002). Mean (95% CI) craving at t = 5 minutes was lower for the cigarette (mean = 1.00, 95% CI = 0.61, 1.39) than either the 3 mg (mean = 2.25, 95% CI = 1.68, 2.82; P < 0.0001) or 6 mg nicotine (mean = 2.19, 95% CI = 1.60, 2.79; P < 0.0001) ONP. CONCLUSIONS: Among adult smokers, using 6-mg nicotine concentration oral nicotine pouches (ONPs) was associated with greater plasma nicotine delivery at 30 minutes than 3-mg ONPs or cigarettes, but neither ONP relieved craving symptoms at 5 minutes as strongly as a cigarette. Accelerating the speed of nicotine delivery in ONPs might increase their misuse liability relative to cigarettes.

Historical Obesity and Early-Onset Cancers: A Propensity-Weighted Analysis of the National Health and Nutrition Examination Survey.

BACKGROUND: The incidence of early-onset obesity-related cancers (diagnosed < 50 years) is increasing in the U.S. We examined the reported historical body mass index (BMI) of adults with early and later-onset cancers to explore relation to obesity. METHODS: We queried the 1999-2018 NHANES database for adults diagnosed with obesity-related cancers (colorectal, non-colorectal gastrointestinal, uterine, breast). We classified early and late-onset cancer based on a diagnosis age of < 50 and ≥ 50 years, respectively. Propensity-weighted analysis was used to compare prior historical BMIs between the matched groups. RESULTS: After weighing, we included 2,966,528 patients with obesity-related cancers, 846,211 (28%) of which were < 50 years. In the matched analysis, 69.1% of early-onset CRC cases were diagnosed as obese (BMI ≥ 30 kg/m2) before cancer diagnosis, compared to 47.2% of late-onset cases (p < 0.03). Similarly, a higher percentage of adults with other early-onset gastrointestinal cancers had prior obesity as compared to the late-onset cohort (70.3% vs. 40.5%, p = 0.0002). BMI showed a trend toward higher values at ages 20-24 for early-onset CRC and 30-34 for other gastrointestinal cancers. In contrast, later-onset CRC and other gastrointestinal cancers exhibited higher BMI values at later ages (30-34 and 35-39, respectively). Early-onset uterine cancer was linked to a higher BMI compared to later-onset cancer (34.0 vs. 31.1 kg/m2, p < 0.0001), with a trend towards a higher BMI before 19 years old. CONCLUSIONS: Our nationally representative data reveal that higher and earlier body fatness in adulthood associates with early-onset gastrointestinal and uterine cancers. These findings underscore the importance of intensifying efforts to combat early-life obesity.

Substitutability of menthol cigarette alternatives: a clinical trial.

INTRODUCTION: This study assessed the substitutability of plausible combustible menthol cigarette alternatives (MCAs) for usual brand menthol cigarettes (UBMCs) in adults who smoke menthol cigarettes. METHODS: Following three in-lab sampling sessions, 80 adults aged 21-50 who smoke menthol cigarettes chose their preferred MCA: (1) a menthol roll-your-own cigarette (mRYO), (2) a menthol filtered little cigar (mFLC) or (3) a non-menthol cigarette (NMC). Participants were instructed to completely substitute their preferred MCA for their UBMC for 1 week and complete daily diaries documenting adherence and subjective effects. At the final lab visit, participants completed concurrent choice and cross-price elasticity tasks with their substitute product and UBMC as the comparator. RESULTS: Most (65%) participants chose mRYO as their preferred product, followed by NMC and mFLC. Adherence to MCA was high for all products across the week (range: 63%-88%). Positive subjective effects for mRYO decreased over time but remained numerically higher than the other MCA products; craving reduction also decreased for NMC across phases. In the progressive ratio task, participants chose their UBMC in 61.7% of choices; this did not differ by preferred MCA, although the median breakpoint was highest for mRYO and similar for mFLC and NMC. Cross-price elasticity comparing UBMC and the preferred product indicated high substitutability of each MCA at phase 3 (I values -0.70 to -0.82). CONCLUSIONS AND RELEVANCE: mRYOs were the most preferred MCA among the study products, but all MCAs were acceptable substitutes for UBMC using behavioural and economic measures in a short-term trial period.Trial registration number NCT04844762.

The sweet spot study-Developing e-liquid product standards for nicotine form and concentration to improve public health: Protocol for a randomized, double-blinded, crossover study.

OBJECTIVES: E-cigarettes pose significant risks to youth, but smokers may benefit from switching to e-cigarettes by reducing their exposure to toxicants, which creates a challenge for the Food and Drug Administration (FDA) in regulating e-cigarettes to protect population health. This study aims to develop e-liquid product standards for nicotine form and concentration that reduce the appeal of e-cigarettes to young people while keeping e-cigarettes available as a safer alternative for smokers. DESIGN AND PARTICIPANTS: A single-visit, double-blinded, randomized crossover design will be used to examine the effects of e-liquids with varying fractions of free-base nicotine (5%, 25%, 45%, 65%, 85%) among a sample of 66 young adult EC users and 66 older adult smokers, across ecologically valid total nicotine concentrations (20 mg or 50 mg/mL). INTERVENTIONS AND OUTCOMES: A 2-puff session will be conducted to test each of the 10 e-liquids in randomly assigned sequences, followed by a 10-minute washout period and participant ratings on appeal and sensory attributes such as throat hit and harshness, as well as behavioral intentions for continued use. Generalized linear mixed models will be used to determine a free-base nicotine level that has limited or no appeal to young adult e-cigarette users while remaining acceptable to smokers. CONCLUSIONS: This study will provide the FDA with scientific evidence regarding the effect of product standards that mandate a minimum threshold for the fraction of free-base nicotine. TRIAL REGISTRATION: The study is registered on clinicaltrials.gov under the identifier NCT05864586.

Brain Injury Is Prevalent and Precedes Tobacco Use among Youth and Young Adults Experiencing Homelessness.

70%+ of youth and young adults experiencing homelessness (YYEH; 14-24 years old) smoke combustible tobacco. Little is known about the prevalence of acquired brain injury (ABI) among youth and young adult smokers experiencing homelessness (YYSEH) and its impact on tobacco use progression-the aim of our study. Through an interviewer-administered survey, YYSEH were asked about timing of tobacco use; exposure to causes of ABI; including brain oxygen deprivation (BOD; strangulation; accidental; choking games) and blunt force head trauma (BFHT; intentional; shaken violently; accidental); and perpetrators of intentional assault. Participants (n = 96) were on average 22 years old and from populations who experience structural disparities; including those minoritized by race (84.4%) and gender/sexual orientation (26.0%). In total, 87% of participants reported at least one exposure to BFHT and 65% to BOD. Intentional injury was more common than accidental. Furthermore, 60.4% of participants (n = 59) were classified as having ABI using the Brain Injury Severity Assessment. A significant proportion of YYSEH living with ABI were exposed to both BFHT and BOD prior to trying (68.5%, p = 0.002) and to first regular use (82.8%, p < 0.001) of tobacco. Among YYSEH with ABI; injury exposure occurred a median of 1 and 5 years before age of first regular tobacco use, dependent on injury mechanism. ABI from intentional violence is prevalent and precedes tobacco use among YYSEH.

Physical Activity Delays Obesity-Associated Pancreatic Ductal Adenocarcinoma in Mice and Decreases Inflammation.

BACKGROUND & AIMS: Obesity is a risk factor for pancreatic ductal adenocarcinoma (PDAC), a deadly disease with limited preventive strategies. Lifestyle interventions to decrease obesity might prevent obesity-associated PDAC. Here, we examined whether decreasing obesity by increased physical activity (PA) and/or dietary changes would decrease inflammation in humans and prevent PDAC in mice. METHODS: Circulating inflammatory-associated cytokines of overweight and obese subjects before and after a PA intervention were compared. PDAC pre-clinical models were exposed to PA and/or dietary interventions after obesity-associated cancer initiation. Body composition, tumor progression, growth, fibrosis, inflammation, and transcriptomic changes in the adipose tissue were evaluated. RESULTS: PA decreased the levels of systemic inflammatory cytokines in overweight and obese subjects. PDAC mice on a diet-induced obesity (DIO) and PA intervention, had delayed weight gain, decreased systemic inflammation, lower grade pancreatic intraepithelial neoplasia lesions, reduced PDAC incidence, and increased anti-inflammatory signals in the adipose tissue compared to controls. PA had additional cancer prevention benefits when combined with a non-obesogenic diet after DIO. However, weight loss through PA alone or combined with a dietary intervention did not prevent tumor growth in an orthotopic PDAC model. Adipose-specific targeting of interleukin (IL)-15, an anti-inflammatory cytokine induced by PA in the adipose tissue, slowed PDAC growth. CONCLUSIONS: PA alone or combined with diet-induced weight loss delayed the progression of PDAC and reduced systemic and adipose inflammatory signals. Therefore, obesity management via dietary interventions and/or PA, or modulating weight loss related pathways could prevent obesity-associated PDAC in high-risk obese individuals.

Adherence to Surveillance Endoscopies Posteradication of Barrett's Esophagus With High-grade Dysplasia or Carcinoma In Situ.

GOALS: We aimed to evaluate factors associated with patient adherence to recommended surveillance guidelines during the first 3 years after endoscopic eradication of Barrett's esophagus (BE) with high-grade dysplasia (HGD) or T1a carcinoma in situ (CIS) and the relationship between adherence and detection of recurrence. BACKGROUND: While surveillance endoscopies after treatment of BE with HGD or T1a CIS are an important component of therapy, it is unclear whether these high-risk patients are adhering to recommended surveillance guidelines. MATERIALS AND METHODS: A total of 123 BE patients who underwent radiofrequency ablation±endoscopic mucosal resection for biopsy-proven HGD, or CIS between January 2010 and November 2018 underwent retrospective review for adherence to surveillance guidelines, patient factors related to adherence, and recurrence of dysplasia or CIS at 12, 24, and 36 months. RESULTS: Of 123 BE patients (89 HGD and 34 CIS), adherence during the first year following treatment was 26.97% for HGD patients and 41.18% for CIS patients, with increasing adherence rates in subsequent years. Patients who received 3 to 4 surveillance endoscopies in the first year posttreatment had significantly higher rates of recurrence detection than patients who received 0 to 2 surveillance endoscopies over this interval ( P =0.01). No patient factors were found to impact adherence significantly. CONCLUSIONS: Adherence to recommended surveillance intervals after endoscopic treatment of BE with HGD or CIS is low, with poor adherence during the first year associated with decreased detection of recurrence. Future studies are needed to evaluate risk factors and develop a potential intervention for poor adherence in this high-risk population.

Rising Rates of Severe Obesity in Adults Younger Than 50 Correspond to Rise in Hospitalizations for Non-malignant Gastrointestinal Disease.

BACKGROUND: Colorectal cancer incidence is rising in adults < 50 years old, possibly due to obesity. Non-malignant colorectal conditions are understudied in this population. We hypothesize that developing severe obesity in young adulthood also corresponds with increased hospitalization rates for non-malignant colorectal conditions. METHODS: We examined annual percent change (APC) in the prevalence of obesity in adults < 50 using the 2009-2014 National Health and Nutrition Examination Survey. Using the 2010-2014 Nationwide Readmission Database, we then compared yearly hospitalization trends for various gastrointestinal conditions and their outcomes in adults < 50 with severe obesity vs. no obesity. RESULTS: The prevalence of obesity increased in adults < 50 years in 2009-2014. This increase was most pronounced for severe obesity (APC of + 12.8%). The rate of patients with severe obesity < 50 who were admitted for gastrointestinal diseases has increased by 7.76% per year in 2010-2014 (p < 0.001). This increase was > 10% per year for colorectal conditions such Clostridium difficile infections (APC + 17.3%, p = 0.002), inflammatory bowel disease (APC + 13.1%, p = 0.001), and diverticulitis (APC + 12.7%, p = 0.002). The hospitalization rate for chronic liver diseases and acute pancreatitis also increased by 12.2% and 10.0% per year, respectively (p < 0.01). In contrast, young adults without obesity had lower hospitalization rate for most gastrointestinal diseases. Furthermore, adults with no obesity had lower mortality rates for appendicitis, diverticulitis, pancreatitis and chronic liver diseases than adults with severe obesity. CONCLUSION: Our data suggest that increased adiposity in young adults is associated with more hospitalization and worse outcomes for infectious/inflammatory gastrointestinal conditions. Future prevention strategies are warranted to ameliorate these trends.

Addiction potential of combustible menthol cigarette alternatives: a randomised cross-over trial.

INTRODUCTION: The Food and Drug Administration (FDA) has issued proposed product standards banning menthol as a characterising flavour in cigarettes and cigars. The public health benefits of these product standards may be attenuated by the role of plausible substitutes in the marketplace. Therefore, the present study examined the addiction potential of plausible combustible menthol alternatives compared with usual brand menthol cigarettes (UBMC). METHODS: Ninety-eight adult menthol cigarette smokers completed four visits, smoking their UBMC at the first session and three menthol cigarette alternatives in random order at the subsequent visits: (1) a preassembled menthol roll-your-own (mRYO) cigarette using menthol pipe tobacco and mentholated cigarette tube, (2) a menthol filtered little cigar (mFLC) and (3) a non-menthol cigarette (NMC). Measures of smoking topography, exhaled carbon monoxide (CO), craving and withdrawal, subjective effects and behavioural economic demand indices were assessed. RESULTS: Compared with UBMC, menthol cigarette alternatives resulted in different puffing topography and CO exposure (except mRYO), and lower levels of positive subjective experience and behavioural economic demand indices. Among the alternative products, participants reported the highest level of positive subjective experience and higher demand for mRYO, compared with mFLC and NMC. Similarly, participants were significantly more likely to want to try again, purchase and use the mRYO product regularly compared with mFLC and NMC. CONCLUSIONS AND RELEVANCE: mRYO cigarettes were the most highly rated cigarette alternative among study products, suggesting their potential appeal as a menthol cigarette substitute and needed inclusion of menthol pipe tobacco and cigarette tubes in FDA's proposed ban.

Accuracy and agreement of a large panel of endosonographers for endomicroscopy-guided virtual biopsy of pancreatic cystic lesions.

BACKGROUND: Although emerging data evidences that EUS-guided needle-based confocal laser endomicroscopy (nCLE) accurately diagnoses pancreatic cystic lesions (PCLs), there are a lack of interobserver agreement (IOA) studies utilizing reference histopathological diagnosis and for specific PCL subtypes. Hence, we sought to assess the IOA, intra-observer reliability (IOR), and diagnostic performance of EUS-nCLE using a large cohort of patients with histopathological diagnosis amongst a broad panel of international observers. METHODS: EUS-nCLE videos (n = 76) of subjects with PCLs [intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), serous cystadenoma (SCA), pseudocyst, and cystic-neuroendocrine tumors/solid pseudopapillary neoplasm (cystic-NET/SPN)], simulating clinical prevalence rates were obtained from 3 prospective studies. An international panel of 13 endosonographers with nCLE experience, blinded to all PCL data, evaluated the video library twice with a two-week washout for PCL differentiation (mucinous vs. non-mucinous) and subtype diagnosis. RESULTS: The IOA (κ = 0.82, 95% CI 0.77-0.87) and IOR (κ = 0.82, 95% CI 0.78-0.85) were "almost perfect" to differentiate mucinous vs. non-mucinous PCLs. For PCL subtype, IOA was highest for SCA (almost perfect; κ = 0.85), followed by IPMN (substantial, κ = 0.72), and cystic-NET/SPN (substantial, κ = 0.73). The IOA was moderate for MCN (κ = 0.47), and pseudocyst (κ = 0.57). Compared to histopathology, observers differentiated mucinous vs. non-mucinous PCLs with high accuracy (94.8%, 95% CI 93.3-96.1). For detecting specific PCLs subtypes, EUS-nCLE was highly accurate in diagnosing non-mucinous cysts (SCA: 98%; cystic-NET/SPN: 96%; pseudocyst: 96%) and slightly less accurate for mucinous lesions (IPMN: 86%; MCN: 84%). CONCLUSION: Diagnosis of PCLs by EUS-nCLE guided virtual biopsy is very accurate and reliable for the most prevalent pancreatic cysts in clinical practice.

Colorectal Neoplasia in CDH1 Pathogenic Variant Carriers: A Multicenter Analysis.

INTRODUCTION: Germline variants in CDH1 are associated with elevated risks of diffuse gastric cancer and lobular breast cancer. It is uncertain whether there is an increased risk of colorectal neoplasia. METHODS: This was a retrospective analysis of colonoscopy outcomes in patients with germline CDH1 pathogenic/likely pathogenic variants. RESULTS: Eighty-five patients were included with a mean age of 46.9 years. Initial colonoscopy found adenomatous polyps in 30 patients (35.3%), including advanced adenomas in 9 (10.6%). No colorectal cancers were identified on index or subsequent colonoscopies (when available). DISCUSSION: CDH1 carriers have colorectal neoplasia identified at similar rates as in the general population. Despite potential difficulties after gastrectomy, colorectal cancer screening remains important in this population.