Changes in weight among individuals with psychiatric conditions or socioeconomic disadvantage assigned to smoke very low nicotine content cigarettes

Nicotine abstinence leads to weight gain, which could be an unintended consequence of a nicotine reduction policy. This secondary analysis used weekly assessments of weight and ratings of "increased appetite/hunger/weight gain" collected in three 12-week, randomized controlled trials evaluating the effects of cigarettes differing in nicotine dose (15.8, 2.4, or 0.4 mg/g) among individuals with affective disorders, opioid use disorder (OUD), and socioeconomically disadvantaged women. Linear mixed models tested differences by dose and time. Analyses first collapsed across populations and then separated out individuals with OUD because biomarkers suggested they used substantially more noncombusted nicotine. Across populations, weight increased significantly over time, averaging 1.03 kg (p < .001), but did not vary by dose nor was there any interaction of dose/time. "Increased appetite/hunger/weight gain" ratings increased significantly as a function of dose, with differences between low and high doses (1.95 and 1.73, respectively, p = .01), but not by time nor any interaction. In the combined group of individuals with affective disorders and socioeconomically disadvantaged women, weight and "increased appetite/hunger/weight gain" ratings increased significantly by dose, with differences between low and high doses (1.43 vs. 0.73 kg, p = .003 and 2.00 vs. 1.76, p = .02, respectively). Among individuals with OUD, there were no significant effects of any kind on either outcome. Individuals with affective disorders and socioeconomically disadvantaged women gained weight and reported more subjective appetite/weight gain when given 0.4, but not 2.4 mg/g cigarettes, despite comparable decreases in nicotine exposure. However, neither change was clinically significant, suggesting minimal short-term adverse consequences of a nicotine reduction policy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Randomized controlled trial of zolpidem as a pharmacotherapy for cannabis use disorder

BACKGROUND

Sleep disturbance is commonly reported among individuals meeting criteria for cannabis use disorder (CUD), and people who use cannabis frequently report sleep disturbance as a contributor to failed quit attempts. The purpose of this study was to measure sleep in individuals enrolled in treatment for CUD, and to determine whether use of hypnotic medication during treatment increased abstinence rates.

METHOD

The study enrolled 127 adults seeking treatment for CUD in a 12-week clinical trial and randomized to receive extended-release zolpidem (zolpidem-XR) or placebo. All participants received computerized behavioral therapy and abstinence-based contingency management. The study conducted in-home ambulatory polysomnography (PSG) assessments at baseline and during treatment to objectively measure sleep. Self-report measures of recent sleep, Insomnia Severity Index (ISI), and drug use (Timeline Follow-Back) were collected at each study visit, and the study confirmed self-reported abstinence via quantitative urine drug testing.

RESULT

Participants randomized to placebo, but not zolpidem-XR exhibited significant sleep disturbance during week 1 of treatment. Sleep disturbance emerged in the zolpidem-XR group after study medication was stopped at the end of treatment. Though participants assigned to the zolpidem-XR condition had qualitatively greater rates of abstinence compared with placebo (27 % versus 15 % negative at end of treatment), the difference was not statistically significant. Treatment retention was poor (about 50 % drop out in both groups) and medication adherence was a challenge without the use of contingent incentives.

CONCLUSION

Results from this randomized controlled trial suggest that zolpidem-XR can attenuate abstinence-induced sleep disturbance early in treatment for CUD, but that sleep problems are likely to emerge after the medication is stopped. Further research should identify alternative pharmacotherapies and behavioral treatments for CUD and elucidate the role of sleep disturbance in the development and maintenance of CUD.

Clinical Trial Design Challenges and Opportunities for Emerging Treatments for Opioid Use Disorder: A Review

Importance

Novel treatments for opioid use disorder (OUD) are needed to address both the ongoing opioid epidemic and long-standing barriers to existing OUD treatments that target the endogenous μ-opioid receptor (MOR) system. The goal of this review is to highlight unique clinical trial design considerations for the study of emerging treatments for OUD that address targets beyond the MOR system. In November 2019, the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration sponsored a meeting to discuss the current evidence regarding potential treatments for OUD, including cannabinoids, psychedelics, sedative-hypnotics, and immunotherapeutics, such as vaccines.

Observations

Consensus recommendations are presented regarding the most critical elements of trial design for the evaluation of novel OUD treatments, such as: (1) stage of treatment that will be targeted (eg, seeking treatment, early abstinence/detoxification, long-term recovery); (2) role of treatment (adjunctive with or independent of existing OUD treatments); (3) primary outcomes informed by patient preferences that assess opioid use (including changes in patterns of use), treatment retention, and/or global functioning and quality of life; and (4) adverse events, including the potential for opioid-related relapse or overdose, especially if the patient is not simultaneously taking maintenance MOR agonist or antagonist medications.

Conclusions and Relevance

Applying the recommendations provided here as well as considering input from people with lived experience in the design phase will accelerate the development, translation, and uptake of effective and safe therapeutics for individuals struggling with OUD.

Potential effects of nicotine content in cigarettes on use of other substances

A national nicotine reduction policy has the potential to reduce cigarette smoking and associated adverse health impacts among vulnerable populations. However, possible unanticipated adverse effects of reducing nicotine content in cigarettes, such as increasing the use of alcohol or other abused substances, must be examined. The purpose of this study was to evaluate the effects of exposure to varying doses of nicotine in cigarettes on use of other substances. This was a secondary analysis (n = 753) of three simultaneous, multisite, double-blind, randomized-controlled trials examining 12 weeks of exposure to study cigarettes varying in nicotine content (0.4, 2.4, 15.8 mg nicotine/g tobacco) among daily smokers from three vulnerable populations: individuals with affective disorders (n = 251), individuals with opioid use disorder (n = 256), and socioeconomically-disadvantaged women of reproductive age (n = 246). Effect of study cigarette assignment on urine toxicology screens (performed weekly) and responses to drug and alcohol use questionnaires (completed at study weeks 6 and 12) were examined using negative binomial regression, logistic regression, or repeated measures analysis of variance, controlling for sex, age, and menthol status. The most common substances identified using urine toxicology included tetrahydrocannabinol (THC; 44.8%), cocaine (9.2%), benzodiazepine (8.6%), and amphetamines (8.0%), with 57.2% of participants testing positive at least once for substance use (27.3% if excluding THC). No significant main effects of nicotine dose were found on any of the examined outcomes. These results suggest that reducing nicotine content does not systematically increase use of other substances, even among individuals at increased risk of substance use. ClinicalTrials.gov Identifiers: NCT02232737, NCT2250664, NCT2250534.

Relating individual differences in the reinforcing value of smoking and dependence severity to nicotine exposure levels in vulnerable populations

Cigarette smoking is overrepresented in populations with psychiatric conditions and socioeconomic disadvantage. Greater understanding of the role of reinforcement and nicotine dependence in smoking among vulnerable populations may facilitate development of better targeted interventions to reduce smoking. Prior research demonstrated that individual differences in the reinforcing value of smoking and nicotine-dependence severity predicted total nicotine-exposure in vulnerable populations. The present study uses multivariate regression to address two aims: (1) Quantify the degree to which the reinforcing value of smoking, assessed using the Cigarette Purchase Task (CPT), and dependence severity assessed using the Fagerström Test of Nicotine Dependence and Brief Wisconsin Inventory of Smoking Dependence Motives (B-WISDM) each account for individual differences in cotinine-plus-3'-hydroxycotinine (COT+3HC) levels. (2) Explore whether there is overlap in the variance accounted for by the CTP, FTND, and B-WISDM. Participants were 628 adults with co-morbid psychiatric conditions or socioeconomic disadvantage who smoked daily. The CPT, FTND, and B-WISDM models accounted for 23.76%, 32.45%, and 29.61% of the variance in COT+3HC levels, respectively. Adding CPT to the FTND model failed to increase the variance accounted for and adding it to the B-WISDM model did so by only 1.2% demonstrating considerable overlap in the variance in nicotine exposure levels accounted for by these three instruments. These results provide new knowledge on the relationship between individual differences in the reinforcing value of smoking and nicotine-exposure levels and suggest differences in reinforcing value may underpin a considerable portion of the variance in nicotine exposure accounted for by dependence severity.

The Impact of the Covid-19 Pandemic on Smoking Among Vulnerable Populations

AIM

While accumulating evidence suggests that people modified their smoking during the ongoing COVID-19 pandemic, it remains unclear whether those most at risk for tobacco-related health disparities did so. The current study examined changes in smoking among several vulnerable smoker populations during the COVID-19 pandemic.

METHODS

A web-based survey was distributed in 2020 to 709 adults with socioeconomic disadvantage, affective disorders, or opioid use disorder who participated in a previous study investigating the effects of very low nicotine content (VLNC) cigarettes on smoking. Current smoking status and rate, and adoption of protective health behaviors in response to the pandemic (eg social distancing, mask wearing) were examined.

RESULTS

Among 332 survey respondents (46.8% response rate), 84.6% were current smokers. Repeated measures ANOVA showed that current cigarettes/day (CPD) was higher during COVID than pre-COVID (12.9 ± 1.0 versus 11.6 ± 1.0; p < .001). Most respondents had adopted protective health behaviors to prevent infection (>79% for all behaviors). More than half indicated that they were still leaving their homes specifically to buy cigarettes (64.6%) and were buying more packs per visit to the store (54.5%) than pre-COVID. Individuals unemployed at the time of the survey experienced greater increases in CPD (from 11.4 ± 1.4 to 13.3 ± 1.4, p = .024) as did those with higher levels of anxiety (from 11.5 ± 1.1 to 13.6 ± 1.1, p < .001).

CONCLUSIONS

Smoking increased during the COVID-19 pandemic in this sample of adults from vulnerable populations, even while most adopted protective health measures to prevent infection. Unemployment and anxiety might identify those at greatest risk for increases in tobacco use.

IMPLICATIONS

Individuals from populations especially vulnerable to smoking might be at risk for greater harm from cigarette smoking during times of pandemic-related stress. Public health interventions are warranted to ameliorate increases in smoking among these populations. Special attention should be paid to those experiencing unemployment and high anxiety.

A systematic review and meta-analysis of delay discounting and cannabis use

Delay discounting reflects the systematic reduction in the value of a consequence by delay to delivery. Theoretical and empirical work suggests that delay discounting is a key behavioral mechanism underlying substance use disorder. Existing work on cannabis use, however, is mixed with many studies reporting null results. The purpose of this review was to provide an in-depth assessment of the association between delay discounting and cannabis use. We conducted metaregression analyses to determine the omnibus correlation between delay discounting and cannabis use, and to evaluate task-based and sample-based moderators. Studies included evaluated an association between delay discounting and cannabis quantity-frequency or severity measures in human participants (27 studies, 61 effect sizes, 24,782 participants). A robust variance estimation method was used to account for dependence among effect sizes. A significant, but small, omnibus effect was observed (r = .082) in which greater cannabis use frequency or severity was associated with greater discounting. Incentive structure and outcome type were each significant moderators in a multiple moderator model such that incentivized tasks correlated with severity measures showed stronger associations (r = .234) than hypothetical tasks correlated with quantity-frequency measures (r = .029). Comparisons to historic effect size data supported the hypothesis that, at present, the relationship between cannabis use and delay discounting appears empirically smaller than for other substances. Future work should explore theoretical rationales explaining this modest relationship involving cannabis use and delay discounting, such as reflecting the smaller magnitude of perceived long-term clinical outcomes associated with cannabis compared to other substances. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Impact of cardiovascular health status on the association between changes in physical activity and major cardiovascular events and mortality among 88,320 adults: outcomes of the Lifelines Cohort Study

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Lifelines Biobank initiative received funding from the Dutch Ministry of Health, Welfare and Sport, the Dutch Ministry of Economic Affairs, the University Medical Center Groningen [UMCG], University Groningen and the Northern Provinces of the Netherlands. The work of T.M.H.E is supported by the Netherlands Heart Foundation [Senior E-Dekker grant #2017T051].

Background. Regular physical activity (PA) improves health. Many observational studies investigated the association between PA and health at a single time-point, but PA might change over time.

Purpose. To examine the association between change in PA and major adverse cardiovascular events (MACE) and all-cause mortality, and to investigate the impact of cardiovascular health status at baseline on these outcomes.

Methods. This study used data from the Lifelines Cohort Study (N = 88,320). Self-reported PA volumes were presented as Metabolic Equivalent of Task (MET) min/week. Change in PA was calculated by subtracting MET-min/week at the first assessment from the second assessment (median interval: 4 yrs), and 5 groups were created; large reduction (&lt; -1500), moderate reduction (-1500 to -250), no change (-250 to 250), moderate improvement (-250 to 250) and large improvement (&gt;1500). The outcome was a combination of MACE and all-cause mortality.

Results. During a median follow-up of 7 years, 667 events occurred among healthy individuals (43 ± 12 yrs, 1% of 69,818) and 599 in individuals with CVRF (55 ± 11 yrs, 3% of 18,502). Adjusted for confounders and baseline PA, healthy individuals with a large reduction in PA had a greater risk of incident MACE and mortality (Table). In CVRF, moderate to large improvements in PA were associated with reductions in adverse outcomes. Risk estimates became stronger in individuals with lower baseline PA (&lt;2000 MET-min/week), Table).

Conclusions. Maintaining PA in healthy individuals and increasing PA in individuals with CVRF over time is important to prevent MACE and mortality. The impact of changes in PA was stronger for individuals with lower baseline PA.

Table. Change of PA, MACE and mortality. Changes in PA Healthy CVRF Large reduction 1.40 [1.02;1.93] 1.27 [0.95;1.70] Moderate reduction 1.22 [0.89;1.68] 0.97 [0.72;1.30] No changes Ref Ref Moderate improvement 1.04 [0.74;1.44] 0.65 [0.47;0.91] Large improvement 0.96 [0.71;1.31] 0.69 [0.51; 0.94] Individuals with lower baseline PA Large reduction 2.24 [0.96;5.21] 2.85 [1.44;5.63] Moderate reduction 1.77 [1.10;2.84] 1.33 [0.89;1.98] No changes Ref Ref Moderate improvement 1.16 [0.73;1.83] 0.49 [0.31;0.76] Large improvement 0.77 [0.48;1.23] 0.58 [0.39;0.86]

Treatment Implications Associated with Cannabis and Tobacco Co-Use

PURPOSE OF THE REVIEW

The goal of this article is to summarize the treatment-focused literature on cannabis and tobacco co-use and the treatment implications of co-use. This review will focus on: 1) the impact of co-use on cessation outcomes, 2) compensatory use/substitution of the non-treated substance among co-users, and 3) treatment interventions to address co-use. This article will highlight the limitations to co-use captured in the literature and offer considerations and directives for co-use research and treatment moving forward.

RECENT FINDINGS

The degree to which co-use affects cessation for a single, targeted substance remains in question, as the literature is largely mixed. Cannabis treatment trials are better equipped to answer these questions given that they do not typically exclude tobacco users. While the relationship between tobacco use and poorer cannabis outcomes appears to have some evidence, the reverse relationship (cannabis use affecting tobacco outcomes) is not consistently supported.

SUMMARY

The co-use of cannabis and tobacco and its impact on single substance cessation and/or compensatory substance use during cessation is generally overlooked in treatment trials, while interventions to address both substances are rare. Capturing co-use adds burden for researchers, clinicians, and participants, but is warranted given the prevalence of co-use and a rapidly changing cannabis and tobacco regulatory environment, which may further complicate co-occurring substance use. Co-users are a heterogeneous population; trials focused on co-users, in addition to better data capture and consistent terminology, will aid in an understanding of nuanced patterns of co-use critical to inform treatment interventions.

Abuse liability of cigarettes with very low nicotine content in pregnant cigarette smokers

The U.S. Food and Drug Administration has proposed reducing the nicotine content of cigarettes to a minimally-addictive level. To our knowledge, this study is the first to examine how pregnant smokers respond to very low nicotine content (VLNC) cigarettes. In Phase 1, participants blindly sampled two VLNC cigarettes (0.4 and 2.4 mg/g of tobacco) and their usual brand (UB) cigarette in separate sessions, then completed a behavioral economic simulation task and measures of subjective effects, craving/withdrawal, and smoking topography. Phase 2 directly compared the relative reinforcing effects of the cigarettes using concurrent choice testing. All possible dose-pair combinations were tested in separate sessions where puffs were earned ad libitum by clicking the code associated with their preferred cigarette 10 times. Phase 3 tested the 0.4 mg/g-UB dose-pair where UB puffs could be earned with a progressively incremented number of clicks (maximum 8400). Ten pregnant smokers in Burlington, VT and Baltimore, MD participated in 2017-2018. Regarding abuse liability, participants chose the 0.4-mg/g dose less than UB (22% vs. 78%) during concurrent choice testing and the 0.4-mg/g dose sustained less demand than the 2.4-mg/g and UB doses on the simulation task. Positive subjective effects were also lower for both VLNC cigarettes vs. UB. Each cigarette reduced nicotine craving/withdrawal and no significant changes indicative of compensatory smoking were noted. Reducing the nicotine content of cigarettes may decrease their abuse liability in pregnant smokers without causing untoward craving/withdrawal or compensatory smoking. Studies of extended exposure to VLNCs in pregnant women are warranted.

The state of clinical outcome assessments for cannabis use disorder clinical trials: A review and research agenda

There is considerable variability in the use of outcome measures in clinical trials for cannabis use disorder (CUD), and a lack of consensus regarding optimal outcomes may have hindered development and approval of new pharmacotherapies. The goal of this paper is to summarize an evaluation of assessment measures and clinical endpoints for CUD clinical trials, and propose a research agenda and priorities to improve CUD clinical outcome assessments. The primary recommendation is that sustained abstinence from cannabis should not be considered the primary outcome for all CUD clinical trials as it has multiple limitations. However, there are multiple challenges to the development of a reliable and valid indicator of cannabis reduction, including the lack of a standard unit of measure for the various forms of cannabis and products and the limitations of currently available biological and self-report assessments. Development of a core toolkit of assessments is needed to both allow flexibility for study design, while facilitating interpretation of outcomes across trials. Four primary agenda items for future research are identified to expedite development of improved clinical outcome assessments for this toolkit: (1) determine whether minimally invasive biologic assays could identify an acute level of cannabis use associated with psychomotor impairment or other cannabis-related harms; (2) create an indicator of quantity of cannabis use that is consistent across product types; (3) examine the presence of cannabis-specific functional outcomes; and (4) identify an optimal duration to assess changes in CUD diagnostic criteria.

Treatment of bone loss in proximal femurs of postmenopausal osteoporotic women with AGN1 local osteo-enhancement procedure (LOEP) increases hip bone mineral density and hip strength: a long-term prospective cohort study

This first-in-human study of AGN1 LOEP demonstrated that this minimally-invasive treatment durably increased aBMD in femurs of osteoporotic postmenopausal women. AGN1 resorption was coupled with new bone formation by 12 weeks and that new bone was maintained for at least 5-7 years resulting in substantially increased FEA-estimated femoral strength.

INTRODUCTION

This first-in-human study evaluated feasibility, safety, and in vivo response to treating proximal femurs of postmenopausal osteoporotic women with a minimally-invasive local osteo-enhancement procedure (LOEP) to inject a resorbable triphasic osteoconductive implant material (AGN1).

METHODS

This prospective cohort study enrolled 12 postmenopausal osteoporotic (femoral neck T-score ≤ - 2.5) women aged 56 to 89 years. AGN1 LOEP was performed on left femurs; right femurs were untreated controls. Subjects were followed-up for 5-7 years. Outcomes included adverse events, proximal femur areal bone mineral density (aBMD), AGN1 resorption, and replacement with bone by X-ray and CT, and finite element analysis (FEA) estimated hip strength.

RESULTS

Baseline treated and control femoral neck aBMD was equivalent. Treated femoral neck aBMD increased by 68 ± 22%, 59 ± 24%, and 58 ± 27% over control at 12 and 24 weeks and 5-7 years, respectively (p < 0.001, all time points). Using conservative assumptions, FEA-estimated femoral strength increased by 41%, 37%, and 22% at 12 and 24 weeks and 5-7 years, respectively (p < 0.01, all time points). Qualitative analysis of X-ray and CT scans demonstrated that AGN1 resorption and replacement with bone was nearly complete by 24 weeks. By 5-7 years, AGN1 appeared to be fully resorbed and replaced with bone integrated with surrounding trabecular and cortical bone. No procedure- or device-related serious adverse events (SAEs) occurred.

CONCLUSIONS

Treating femurs of postmenopausal osteoporotic women with AGN1 LOEP results in a rapid, durable increase in aBMD and femoral strength. These results support the use and further clinical study of this approach in osteoporotic patients at high risk of hip fracture.

A web-based episodic specificity and future thinking session modulates delay discounting in cannabis users

Episodic future thinking (EFT), a brief intervention involving mental simulation of positive future events, improves delay discounting (DD) in nicotine and alcohol dependent individuals. This study is the first to assess effects of a single-session, online episodic training (ET) on constructs that might impact cannabis use and cannabis use disorder. A sample of 200 active cannabis users recruited via Amazon Mechanical Turk were randomized to an EFT group (n = 102) or an episodic recent thinking control group (ERT; n = 98). A novel episodic specificity induction (ES) was included to enhance quality of episodic thinking for the ET group, and an ES attention control was provided to the ERT group (control training group; CT). Quality and manipulation ratings of event excitement, vividness, importance, and enjoyment of trainings were collected in addition to DD tasks (gains and losses) and readiness to change cannabis use. The ET group reported higher overall quality and manipulation ratings than did the CT group (p < .001, d = 0.79). DD of gains was lower in the ET relative to those of the CT group after controlling for relevant variables (p = .003, d = 0.48), unlike DD of losses (p = .50, d = 0.11). The ET group showed larger pre/post increases in readiness to change, but they were not statistically significant (p = .069, d = 0.26). These effects, following a session of online ET, suggests that ET may positively impact factors related to reduction in cannabis use. Differential effects of EFT and ES components on DD and the development of ET as an adjunctive mHealth intervention targeting reduction in cannabis use appears warranted. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Emerging Trends in Cannabis Administration Among Adolescent Cannabis Users

PURPOSE

The legal landscape of cannabis availability and use in the United States is rapidly changing. As the heterogeneity of cannabis products and methods of use increases, more information is needed on how these changes affect use, especially in vulnerable populations such as youth.

METHODS

A national sample of adolescents aged 14-18 years (N = 2,630) were recruited online through advertisements displayed on Facebook and Instagram to complete a survey on cannabis. The survey assessed patterns of edible use, vaping, and smoking cannabis, and the associations among these administration routes and use of other substances.

RESULTS

The most frequent and consistent route of cannabis use was smoking (99% lifetime), with substantial numbers reporting vaping (44% lifetime) and edible use (61% lifetime). The majority of those who had experimented with multiple routes of cannabis administration continued to prefer smoking, and the most common pattern of initiation was smoking, followed by edibles and then vaping. In addition to cannabis use, adolescents reported high rates of nicotine use and substantial use of other substances. Adolescents who used more cannabis administration routes tended to also report higher frequency of other substances tried.

CONCLUSIONS

Additional work is needed to determine whether the observed adolescent cannabis administration patterns are similar across different samples and sampling methods as well as how these trends change over time with extended exposure to new products and methods. The combined knowledge gained via diverse sampling strategies will have important implications for the development of regulatory policy and prevention and intervention efforts.

Systematic review of outcome domains and measures used in psychosocial and pharmacological treatment trials for cannabis use disorder

Cannabis use disorder (CUD) is prevalent and demand for treatment is increasing, yet few individuals engage in formal treatment and the efficacy of established interventions for CUD is modest. Existing clinical trials evaluating psychosocial and pharmacological treatments for CUD have incorporated a wide variety of measures for assessing cannabis use outcomes, including abstinence, self-reported frequency and quantity used, withdrawal, use/dependence severity, and other psychosocial outcomes. The heterogeneity of measures and outcomes has limited quantitative analyses of the comparative effectiveness of existing interventions. The purpose of this systematic review is to: 1) identify and characterize approaches for measuring cannabis use in existing CUD intervention trials, including abstinence, frequency and quantity of use, and 2) summarize measures used to assess treatment efficacy in other outcome domains (e.g., cannabis use severity, psychosocial functioning, cannabis withdrawal), and provide a platform for future research to evaluate which outcome measures are most likely to reflect treatment efficacy and clinically significant improvement in other outcome domains.

Sequential and simultaneous treatment approaches to cannabis use disorder and tobacco use

Tobacco smoking among those seeking treatment for cannabis use disorder (CUD) is common and is a negative predictor of cannabis outcomes. Quitting tobacco may be beneficial for those seeking to quit cannabis use. This initial proof of concept, controlled trial was designed to compare a simultaneous versus sequential tobacco intervention among those seeking treatment for CUD. Sixty-seven adults received either a simultaneous (SIM) or sequential (SEQ) approach to tobacco cessation in the context of outpatient treatment for CUD. A tobacco intervention (TI) that combined web-based counseling with nicotine replacement therapy (NRT) was provided during weeks 1-12 for SIM and was delayed until weeks 13-24 for SEQ. During weeks 1-12, no between-condition significant differences were observed on treatment participation or cannabis use outcomes. The majority of SIM participants initiated TI counseling (62%), 50% made at least one quit attempt and 41% initiated NRT. Interestingly, 39% in SEQ made tobacco quit attempts and 18% initiated NRT on their own before the TI was offered to them. However, only 30% of those in SEQ continued treatment during weeks 13-24, which compromised between-condition comparisons following the TI, but illustrated a potential clinical concern with delaying the TI. Tobacco cessation outcomes generally were poor and did not differ between conditions. This initial controlled trial suggests that addressing tobacco use during CUD treatment is acceptable and generates action towards tobacco cessation. Additional trials testing more intensive TI models may be necessary to identify more efficacious interventions for co-use of cannabis and tobacco.

Co-use of cannabis, tobacco, and alcohol during adolescence: policy and regulatory implications

Legislative reforms have legalized use of cannabis for medical and recreational purposes. Efforts to evaluate the public health impact of these changes have predominantly focused on determining whether liberalizing cannabis policies has increased cannabis use patterns. Co-use of cannabis and other licit substances, namely tobacco and alcohol, is common during the developmental period of adolescence, which is generally characterized by an increase in risk-taking and novelty-seeking. However, limited research has sought to evaluate the potential implications of reforms to medical and recreational cannabis laws on concurrent and simultaneous use of cannabis, tobacco, and alcohol during adolescence. The current report reviews the extant literature detailing the prevalence and outcomes associated with concurrent and simultaneous cannabis-tobacco and cannabis-alcohol use, including recent work that has examined how concurrent and simultaneous use may be influenced by cannabis reform. This review details how the cannabis landscape and cannabis retail marketplace have evolved and briefly summarizes the corresponding policy and regulatory challenges that have emerged. The report concludes with a focused cannabis co-use research agenda that adopts different strategies including behavioural economic, self-administration, and survey research methods.

The effect of high-dose dronabinol (oral THC) maintenance on cannabis self-administration

BACKGROUND

There is a clear need for advancing the treatment of cannabis use disorders. Prior research has demonstrated that dronabinol (oral THC) can dose-dependently suppress cannabis withdrawal and reduce the acute effects of smoked cannabis. The present study was conducted to evaluate whether high-dose dronabinol could reduce cannabis self-administration among daily users.

METHODS

Non-treatment seeking daily cannabis users (N = 13) completed a residential within-subjects crossover study and were administered placebo, low-dose dronabinol (120 mg/day; 40 mg tid), or high-dose dronabinol (180-240 mg/day; 60-80 mg tid) for 12 consecutive days (order counterbalanced). During each 12-day dronabinol maintenance phase, participants were allowed to self-administer smoked cannabis containing <1% THC (placebo) or 5.7% THC (active) under forced-choice (drug vs. money) or progressive ratio conditions.

RESULTS

Participants self-administered significantly more active cannabis compared with placebo in all conditions. When active cannabis was available, self-administration was significantly reduced during periods of dronabinol maintenance compared with placebo maintenance. There was no difference in self-administration between the low- and high-dose dronabinol conditions.

CONCLUSIONS

Chronic dronabinol dosing can reduce cannabis self-administration in daily cannabis users and suppress withdrawal symptoms. Cannabinoid agonist medications should continue to be explored for therapeutic utility in the treatment of cannabis use disorders.

Does Tobacco Abstinence Decrease Reward Sensitivity? A Human Laboratory Test

INTRODUCTION

Animal studies report abstinence from nicotine makes rewards less rewarding; however, the results of human tests of the effects of cessation on reward sensitivity are mixed. The current study tested reward sensitivity in abstinent smokers using more rigorous methods than most prior studies.

METHODS

A human laboratory study compared outcomes for 1 week prior to quitting to those during 4 weeks postquit. The study used smokers trying to quit, objective and subjective measures, multiple measures during smoking and abstinence, and monetary rewards to increase the prevalence of abstinence. Current daily smokers (n = 211) who were trying to quit completed an operant measure of reward sensitivity and a survey of pleasure from various rewards as well as self-reports of anhedonia, delay discounting, positive affect, and tobacco withdrawal twice each week. A comparison group of long-term former smokers (n = 67) also completed the tasks weekly for 4 weeks. Primary analyses were based on the 61 current smokers who abstained for all 4 weeks.

RESULTS

Stopping smoking decreased self-reported pleasure from rewards but did not decrease reward sensitivity on the operant task. Abstinence also decreased self-reported reward frequency and increased the two anhedonia measures. However, the changes with abstinence were small for all outcomes (6%-14%) and most lasted less than a week.

CONCLUSIONS

Abstinence from tobacco decreased most self-report measures of reward sensitivity; however, it did not change the objective measure. The self-report effects were small.

IMPLICATIONS

Animal research suggests that nicotine withdrawal decreases reward sensitivity. Replication tests of this in humans have produced inconsistent results. We report what we believe is a more rigorous test. We found smoking abstinence slightly decreases self-reports of reward sensitivity but does not do so for a behavioral measure of reward sensitivity.

Cannabis Withdrawal: A Review of Neurobiological Mechanisms and Sex Differences

PURPOSE OF REVIEW

This report provides an updated overview of pre-clinical and clinical research on the etiology and biological substrates of the cannabis withdrawal syndrome.

RECENT FINDINGS

Long-term cannabis use is associated with downregulation of type-1 cannabinoid receptors (CB1). Reduced CB1 receptor density is related to increased withdrawal during early abstinence, and the reduction in CB1 receptor density reverses with extended abstinence. Females have been shown to have increased rate and severity of a subset of cannabis withdrawal symptoms compared with men.

SUMMARY

Recent studies have extended knowledge of the biological processes and individual difference variables that influence cannabis withdrawal. However, caveats include small sample sizes in clinical studies, participant samples that are predominantly male, and limited examinations of endocannabinoids, enzymes that degrade endocannabinoids, negative allosteric modulators, and other neurobiological systems that may directly impact cannabis withdrawal symptom expression.

Cardiopulmonary assessment of patients with systemic sclerosis for hematopoietic stem cell transplantation: recommendations from the European Society for Blood and Marrow Transplantation Autoimmune Diseases Working Party and collaborating partners

Systemic sclerosis (SSc) is a rare disabling autoimmune disease with a similar mortality to many cancers. Two randomized controlled trials of autologous hematopoietic stem cell transplantation (AHSCT) for SSc have shown significant improvement in organ function, quality of life and long-term survival compared to standard therapy. However, transplant-related mortality (TRM) ranged from 3–10% in patients undergoing HSCT. In SSc, the main cause of non-transplant and TRM is cardiac related. We therefore updated the previously published guidelines for cardiac evaluation, which should be performed in dedicated centers with expertize in HSCT for SSc. The current recommendations are based on pre-transplant cardiopulmonary evaluations combining pulmonary function tests, echocardiography, cardiac magnetic resonance imaging and invasive hemodynamic testing, initiated at Northwestern University (Chicago) and subsequently discussed and endorsed within the EBMT ADWP in 2016.

Characteristics and Evaluation of Geographically Distant vs Geographically Nearby Living Kidney Donors

BACKGROUND

Living donor kidney transplant (LDKT) can be impeded by multiple barriers. One possible barrier to LDKT is a large physical distance between the living donor's home residence and the procuring transplant center.

METHODS

We performed a retrospective, single-center study of living kidney donors in the United States who were geographically distant (residing ≥150 miles) from our transplant center. Each distant donor was matched to 4 geographically nearby donors (<150 miles from our center) as controls.

RESULTS

From 2007 to 2010, of 429 live kidney donors, 55 (12.8%) were geographically distant. Black donors composed a higher proportion of geographically distant vs nearby donors (34.6% vs 15.5%), whereas Hispanic and Asian donors composed a lower proportion (P = .001). Distant vs nearby donors had similar median times from donor referral to actual donation (165 vs 161 days, P = .81). The geographically distant donors lived a median of 703 miles (25% to 75% range, 244 to 1072) from our center and 21.2 miles (25% to 75% range, 9.8 to 49.7) from the nearest kidney transplant center. The proportion of geographically distant donors who had their physician evaluation (21.6%), psychosocial evaluation (21.6%), or computed tomography angiogram (29.4%) performed close to home, rather than at our center, was low.

CONCLUSIONS

Many geographically distant donors live close to transplant centers other than the procuring transplant center, but few of these donors perform parts of their donor evaluation at these closer centers. Black donors comprise a large proportion of geographically distant donors. The evaluation of geographically distant donors, especially among minorities, warrants further study.

Smoking, vaping, eating: Is legalization impacting the way people use cannabis?

BACKGROUND

In the context of the shifting legal landscape of medical cannabis, different methods of cannabis administration have important public health implications. How medical marijuana laws (MML) may influence patterns of use of alternative methods of cannabis administration (vaping and edibles) compared to traditional methods (smoking) is unclear. The purpose of this study was to determine if the prevalence of use of alternative methods of cannabis administration varied in relation to the presence of and variation in MMLs among states in the United States.

METHOD

Using Qualtrics and Facebook, we collected survey data from a convenience sample of n=2838 individuals who had used cannabis at least once in their lifetime. Using multiple sources, U.S. states were coded by MML status, duration of MML status, and cannabis dispensary density. Adjusted logistic and linear regression analyses were used to analyze outcomes of ever use, preference for, and age of initiation of smoking, vaping, and edibles in relation to MML status, duration of MML status, and cannabis dispensary density.

RESULTS

Individuals in MML states had a significantly higher likelihood of ever use of vaping (OR: 2.04, 99% CI: 1.62-2.58) and edibles (OR: 1.78, 99% CI: 1.39-2.26) than those in states without MMLs. Longer duration of MML status and higher dispensary density were also significantly associated with ever use of vaping and edibles.

CONCLUSIONS

MMLs are related to state-level patterns of utilization of alternative methods of cannabis administration. Whether discrepancies in MML legislation are causally related to these findings will require further study. If MMLs do impact methods of use, regulatory bodies considering medical or recreational legalization should be aware of the potential impact this may have on cannabis users.

Online survey characterizing vaporizer use among cannabis users

BACKGROUND

Along with changes in cannabis laws in the United States and other countries, new products for consuming cannabis are emerging, with unclear public health implications. Vaporizing or "vaping" cannabis is gaining popularity, but little is known about its prevalence or consequences.

METHODS

This study characterized the prevalence and current patterns of vaping cannabis among a large national sample of cannabis users. An online survey was distributed through Facebook ads targeting individuals with interests related to cannabis use. The sample comprised 2910 cannabis users (age: 18-90, 84% male, 74% Caucasian).

RESULTS

A majority (61%) endorsed lifetime prevalence of ever vaping, 37% reported vaping in the past 30 days, 20% reported vaping more than 100 lifetime days, and 12% endorsed vaping as their preferred method. Compared to those that had never vaped, vaporizer users were younger, more likely to be male, initiated cannabis at an earlier age, and were less likely to be African American. Those that preferred vaping reported it to be healthier, better tasting, produced better effects, and more satisfying. Only 14% reported a reduction in smoking cannabis since initiating vaping, and only 5% mixed cannabis with nicotine in a vaporizer. Many cannabis users report vaping cannabis, but currently only a small subset prefers vaping to smoking and reports frequent vaping.

CONCLUSION

Increases in availability and marketing of vaping devices, and the changing legal status of cannabis in the United States and other countries may influence patterns of use. Frequent monitoring is needed to assess the impact of changing cannabis laws and regulations.

Vaping cannabis (marijuana): parallel concerns to e-cigs?

The proliferation of vaporization ('vaping') as a method for administering cannabis raises many of the same public health issues being debated and investigated in relation to e-cigarettes (e-cigs). Good epidemiological data on the prevalence of vaping cannabis are not yet available, but with current trends towards societal approval of medicinal and recreational use of cannabis, the pros and cons of vaping cannabis warrant study. As with e-cigs, vaping cannabis portends putative health benefits by reducing harm from ingesting toxic smoke. Indeed, vaping is perceived and being sold as a safer way to use cannabis, despite the lack of data on the health effects of chronic vaping. Other perceived benefits include better taste, more efficient and intense effects and greater discretion which allows for use in more places. Unfortunately, these aspects of vaping could prompt an increased likelihood of trying cannabis, earlier age of onset, more positive initial experiences, and more frequent use, thereby increasing the probability of problematic use or addiction. Sales and marketing of vaping devices with no regulatory guidelines, especially related to advertising or product development targeting youth, parallels concerns under debate related to e-cigs and youth. Thus, the quandary of whether or not to promote vaping as a safer method of cannabis administration for those wishing to use cannabis, and how to regulate vaping and vaping devices, necessitates substantial investigation and discussion. Addressing these issues in concert with efforts directed towards e-cigs may save time and energy and result in a more comprehensive and effective public health policy on vaping.

Confirmation of the trials and tribulations of vaping

Responses to our article indicate consensus on the need for expedited scientific and regulatory action related to vaping of cannabis and other substances to curtail untoward public health impact and identify potential benefits. How to speed up science, increase knowledge and enact responsible regulatory policy poses a formidable challenge.

Outcomes from a computer-assisted intervention simultaneously targeting cannabis and tobacco use

BACKGROUND

Cannabis users frequently report concurrent tobacco use, and tobacco use is associated with poorer outcomes during treatment for cannabis use disorders (CUD). Interventions that simultaneously target both tobacco and cannabis use disorders may enhance cessation outcomes for either or both substances.

METHODS

This study evaluated an intervention integrating highly effective treatments for cannabis and tobacco use disorders. Thirty-two participants meeting diagnostic criteria for CUD and reporting daily tobacco use were enrolled in a 12-week computer-assisted behavioral treatment for CUD. Participants were encouraged to participate in a tobacco intervention that included a computer-assisted behavioral treatment tailored for tobacco and cannabis co-users, and nicotine-replacement therapy (NRT). Cannabis and tobacco outcomes were evaluated using descriptive statistics and were compared to a historical control group that received treatment for CUD but not tobacco.

RESULTS

Participants achieved 3.6±4.3 consecutive weeks of cannabis abstinence, which was comparable to the historical control group (3.1±4.4). A majority of the sample (78%) completed at least one tobacco module and 44% initiated NRT. Over half (56%) initiated tobacco quit attempts, and 28% were tobacco abstinent for at least two consecutive weeks. Participants showed greater reduction in tobacco use (cigarettes per day) than the historical control group, but differences in tobacco abstinence rates during the final month of treatment were not statistically significant (12.5% vs. 4%).

CONCLUSION

Findings suggest that providing a tobacco intervention during treatment for CUD is feasible and may positively impact tobacco use without negatively affecting cannabis use outcomes.

Specific dimensions of impulsivity are differentially associated with daily and non-daily cigarette smoking in young adults

Young adults are at risk for initiation of tobacco use and progression to tobacco dependence. Not every person who smokes cigarettes becomes tobacco dependent, however, and non-daily smoking is becoming more prevalent among those who use tobacco. It is likely that individual differences in psychosocial and behavioral factors influence risk for engaging in non-daily and daily cigarette smoking. The objective of this study was to investigate the associations between impulsivity and smoking status in young adults who vary in frequency of cigarette smoking. Young adult first-year college students between the ages of 18-24 (512) were classified to one of three groups: non-smokers, non-daily smokers, or daily smokers, and impulsivity was assessed using the UPPS-P (negative and positive urgency, lack of premeditation, lack of perseverance, sensation seeking). When all impulsivity dimensions were used simultaneously to predict smoking status, negative urgency predicted increased risk of membership in the daily smoking group and lack of premeditation predicted increased risk of membership in the non-daily smoking group. These results suggest that dimensions of impulsivity may contribute differentially to forms of smoking behavior in young adults.

A comparison of delay discounting in adolescents and adults in treatment for cannabis use disorders

Delay discounting is associated with problematic substance use and poorer treatment outcomes in adolescents and adults with substance use disorders. Although some research has addressed delay discounting among individuals with cannabis use disorders (CUDs), results have been equivocal, and no study has examined whether discounting rates differ between adolescent and adult cannabis users. The aim of this study was to compare discounting rates between adolescents and adults in treatment for CUD to determine whether discounting at intake or changes in discounting across treatment differed between age groups. Participants were 165 adolescents and 104 adults enrolled in treatment for CUD. Participants completed a delay discounting task at intake and end of treatment for 2 commodities (money and cannabis) at 2 different magnitudes ($100 and $1,000). Repeated measures mixed models examined differences in discounting rates by commodity and magnitude across age groups at intake and changes in discounting across treatment. At intake, adolescents discounted money more than adults whereas adults showed greater discounting at $100 magnitude than $1,000. In addition, adults had greater decreases in discounting of cannabis over the course of treatment. Overall, adolescents appeared less sensitive to changes in magnitude of rewards, discounted money at higher rates, and showed less improvement in discounting over the course of treatment compared to adults. Comparing delay discounting in adolescents and adults with CUD can contribute to a better understanding of how development influences the effect of discounting on substance use to better inform treatment for substance use disorders.

Influence of neurobehavioral incentive valence and magnitude on alcohol drinking behavior

The monetary incentive delay (MID) task is a widely used probe for isolating neural circuitry in the human brain associated with incentive motivation. In the present functional magnetic resonance imaging (fMRI) study, 82 young adults, characterized along dimensions of impulsive sensation seeking, completed a MID task. fMRI and behavioral incentive functions were decomposed into incentive valence and magnitude parameters, which were used as predictors in linear regression to determine whether mesolimbic response is associated with problem drinking and recent alcohol use. Alcohol use was best explained by higher fMRI response to anticipation of losses and feedback on high gains in the thalamus. In contrast, problem drinking was best explained by reduced sensitivity to large incentive values in mesolimbic regions in the anticipation phase and increased sensitivity to small incentive values in the dorsal caudate nucleus in the feedback phase. Altered fMRI responses to monetary incentives in mesolimbic circuitry, particularly those alterations associated with problem drinking, may serve as potential early indicators of substance abuse trajectories.

Treatment models for targeting tobacco use during treatment for cannabis use disorder: case series

Approximately 50% of individuals seeking treatment for cannabis use disorders (CUD) also smoke tobacco, and tobacco smoking is a predictor of poor outcomes for those in treatment for CUD. Quitting tobacco is associated with long-term abstinence from alcohol and illicit drugs, yet there are no established treatments for CUD that also target tobacco smoking. This report highlights issues related to cannabis and tobacco co-use and discusses potential treatment approaches targeting both substances. Data is shared from the first six participants enrolled in an intervention designed to simultaneously target tobacco use in individuals seeking treatment for CUD. The twelve-week program comprised computer-assisted delivery of Motivational Enhancement Therapy, Cognitive Behavioral Therapy, and Contingency Management, i.e., abstinence-based incentives for CUD. In addition, participants were encouraged to complete an optional tobacco intervention consisting of nicotine-replacement therapy and computer-assisted delivery of a behavioral treatment tailored for tobacco and cannabis users. All participants completed the cannabis intervention and at least a portion of the tobacco intervention: all completed at least one tobacco computer module (mean=2.5 modules) and 50% initiated nicotine replacement therapy. Five of six participants achieved abstinence from cannabis. The number of tobacco quit attempts was lower than expected, however all participants attempted to reduce tobacco use during treatment. Simultaneously targeting tobacco during treatment for CUD did not negatively impact cannabis outcomes. Participation in the tobacco intervention was high, but cessation outcomes were poor suggesting that alternative strategies might be needed to more effectively prompt quit attempts and enhance quit rates.

Pain distribution and predictors of widespread pain in the immediate aftermath of motor vehicle collision

BACKGROUND

Musculoskeletal pain is common after motor vehicle collision (MVC). The study objective was to evaluate distribution of pain and predictors of widespread musculoskeletal pain in the early aftermath (within 48 h) of collision.

METHODS

European American adults aged 18-65 years presenting to the emergency department (ED) after collision who were discharged to home after evaluation were eligible. Evaluation included an assessment of reported pre-collision psychological characteristics, crash characteristics, current pain severity and location, and current psychological symptoms. Adjusted risk ratios were estimated using generalized linear models.

RESULTS

Among 890 participants included in the study, 589/890 (66%) had pain in three or more regions, and 192/890 (22%) had widespread musculoskeletal pain (pain in seven or more regions). In adjusted analyses, the presence of widespread pain was strongly associated with depressive and somatic symptoms prior to collision, pain catastrophizing, and acute psychological symptoms, and was not associated with most collision characteristics (road speed limit, extent of vehicle damage, collision type, driver vs. passenger, airbag deployment). The reported number of body regions that struck an object during the collision was associated with both reported pre-collision depressive symptoms and with widespread pain.

CONCLUSION

More than one in five individuals presenting to the ED in the hours after MVC have widespread pain. Widespread pain is strongly associated with patient characteristics known to be modulated by supraspinal mechanisms, suggesting that stress-induced hyperalgesia may influence acute widespread pain after collision.

Power-efficient III-V/silicon external cavity DBR lasers

We report the design and characterization of external-cavity DBR lasers built with a III-V-semiconductor reflective-SOA with spot-size converter edge-coupled to SOI waveguides containing Bragg grating mirrors. The un-cooled lasers have wall-plug-efficiencies of up to 9.5% at powers of 6 mW. The lasers are suitable for making power efficient, hybrid WDM transmitters in a CMOS-compatible SOI optical platform.

Effects of 24 hours of tobacco withdrawal and subsequent tobacco smoking among low and high sensation seekers

INTRODUCTION

Previous studies have indicated that high sensation seekers are more sensitive to the reinforcing effects of nicotine, initiate smoking at an earlier age, and smoke greater amounts of cigarettes. This study examined the influence of sensation-seeking status on tobacco smoking following deprivation in regular tobacco users.

METHODS

Twenty healthy tobacco-smoking volunteers with low or high impulsive sensation-seeking subscale scores completed 2 consecutive test days per week for 3 consecutive weeks. Each week, a range of self-report, performance, and cardiovascular assessments were completed during ad libitum smoking on Day 1 and before and after the paced smoking of a tobacco cigarette containing 0.05, 0.6, or 0.9 mg of nicotine following 24 hr of tobacco deprivation on Day 2. In addition, self-administration behavior was analyzed during a 2-hr free access period after the initial tobacco administration.

RESULTS

In high sensation seekers, tobacco smoking independent of nicotine yield ameliorated deprivation effects, whereas amelioration of deprivation effects was dependent on nicotine yield among low sensation seekers. However, this effect was limited to a small subset of measures. Subsequent cigarette self-administration increased in a nicotine-dependent manner for high sensation seekers only.

CONCLUSIONS

Compared with low sensation seekers, high sensation seekers were more sensitive to the withdrawal relieving effects of nonnicotine components of smoking following 24 hr of deprivation on selective measures and more sensitive to nicotine yield during subsequent tobacco self-administration. These results are consistent with studies suggesting that factors driving tobacco dependence may vary as a function of sensation-seeking status.

Prolonged duration of craving, mood, and autonomic responses elicited by cues and imagery in smokers: Effects of tobacco deprivation and sex

Increases in self-reported craving and changes in autonomic functioning are reliably elicited when smokers are exposed to tobacco-related stimuli compared with neutral stimuli. However, few studies have reported the time course of cue-elicited craving or have directly compared the effectiveness of smoking cues versus imagery to evoke a craving response. In addition to these two issues, we investigated the influence of tobacco deprivation and sex on craving, mood, and autonomic responses. Sixty cigarette smokers (30 men, 30 women) were tested in two counterbalanced sessions, one after overnight tobacco deprivation and one during ad libitum smoking. At each session, participants were exposed to four randomized experimental trials: smoking imagery, neutral imagery, smoking cues, and neutral cues. Tobacco craving and mood were assessed repeatedly and physiological measures were recorded continuously for 30 min after imagery or cue exposure. Compared with neutral trials, smoking cues and smoking imagery reliably increased tobacco craving, negative mood, heart rate, and blood pressure and decreased positive mood ratings. Changes were observed immediately after cue and imagery presentation and remained unchanged for 30 min. Responding was greater in the nondeprived condition, and cues elicited more robust responding than imagery for most measures. Women responded more robustly to smoking cues only in the nondeprived condition, whereas imagery evoked greater responses in men during both conditions. These findings provide new data on the time course, magnitude, and tobacco deprivation effects on elicited craving. Sex differences were dependent on stimulus type and deprivation condition.

Comparisons of leisure-time physical activity and cardiorespiratory fitness as predictors of all-cause mortality in men and women

OBJECTIVE

To examine the combined associations and relative contributions of leisure-time physical activity (PA) and cardiorespiratory fitness (CRF) with all-cause mortality.

DESIGN

Prospective cohort study. Setting Aerobics centre longitudinal study.

PARTICIPANTS

31,818 men and 10 555 women who received a medical examination during 1978-2002. Assessment of risk factors Leisure-time PA assessed by self-reported questionnaire; CRF assessed by maximal treadmill test. Main outcome measures All-cause mortality until 31 December 2003.

RESULTS

There were 1492 (469 per 10,000) and 230 (218 per 10,000) deaths in men and women, respectively. PA and CRF were positively correlated in men (r = 0.49) and women (r = 0.47) controlling for age (p < 0.001 for both). PA was inversely associated with mortality in multivariable Cox regression analysis among men, but the association was eliminated after further adjustment for CRF. No significant association of PA with mortality was observed in women. CRF was inversely associated with mortality in men and women, and the associations remained significant after further adjustment for PA. In the PA and CRF combined analysis, compared with the reference group "not meeting the recommended PA (< 500 metabolic equivalent-minute/week) and unfit", the relative risks (95% CIs) of mortality were 0.62 (0.54 to 0.72) and 0.61 (0.44 to 0.86) in men and women "not meeting the recommended PA and fit", 0.96 (0.61 to 1.53) and 0.93 (0.33 to 2.58) in men and women "meeting the recommended PA and unfit" and 0.60 (0.51 to 0.70) and 0.56 (0.37 to 0.85) in men and women "meeting the recommended PA and fit", respectively.

CONCLUSIONS

CRF was more strongly associated with all-cause mortality than PA; therefore, improving CRF should be encouraged in unfit individuals to reduce risk of mortality and considered in the development of future PA guidelines.

Interaction between udenafil and tamsulosin in rats: non-competitive inhibition of tamsulosin metabolism by udenafil via hepatic CYP3A1/2

BACKGROUND AND PURPOSE

Orthostatic hypotension has been observed when PDE 5 (cGMP-specific phosphodiesterase type 5) inhibitors are co-administered with alpha-adrenoceptor antagonists. Here we assessed the pharmacokinetic and haemodynamic interactions between udenafil and tamsulosin in rats, as both drugs are metabolized via rat hepatic cytochrome P450 3A1/2.

EXPERIMENTAL APPROACH

Interactions between the two drugs were evaluated in rats after simultaneous 1 or 15 min i.v. infusion or after p.o. administration of udenafil (30 mg x kg(-1)) and/or tamsulosin (1 mg x kg(-1)). In vitro metabolism of tamsulosin with udenafil was measured to obtain the inhibition constant (K(i)) and [I]/K(i) ratio of udenafil.

KEY RESULTS

The total area under the plasma concentration-time curve from time zero to time infinity (AUC)s (or AUC(0-4 h)) of tamsulosin were significantly greater after 15 min of i.v. infusion or after oral administration with udenafil, compared with tamsulosin alone. The hepatic first-pass metabolism of tamsulosin was inhibited by udenafil, and the inhibition in vitro was in a non-competitive mode. The arterial systolic blood pressure was significantly lower at 5, 10 and 60 min after oral co-administration of the drugs.

CONCLUSIONS AND IMPLICATIONS

The significantly greater AUC of tamsulosin after i.v. and p.o. administration of both drugs may be attributable to non-competitive inhibition of cytochrome P450 3A1/2-mediated hepatic tamsulosin metabolism by udenafil. The inhibition was also observed in human liver S9 fractions, suggesting that a reassessment of the oral dosage of tamsulosin is necessary when udenafil and tamsulosin are co-administered to patients with benign prostatic hyperplasia.

Expression patterns of microRNAs in the chorioamniotic membranes: a role for microRNAs in human pregnancy and parturition

MicroRNAs (miRNAs) are involved in the post-transcriptional regulation of gene expression during development. This study was performed to determine gestational age-dependent changes in miRNA expression in the chorioamniotic membranes and to assess the significance of miRNAs in human pregnancy and parturition. The expression profile of 455 miRNAs was compared between patients at term without labour (TNL: n = 10), in labour (TL: n = 10), and preterm labour (PTL: n = 10) using microarrays. A total of 39 miRNAs were differentially expressed between term and preterm cases, of which 31 (79.5%) were down-regulated at term. Expression of ten miRNAs, including miR-338, differentially expressed between PTL and TL groups was decreased at term. Computational analyses using miRBase Targets have identified PLA2G4B, a phospholipase implicated in parturition, as a putative target of miR-338. Inhibition of endogenous miR-338 with anti-miR-338 increased the mRNA and protein expression of PLA2G4B in decidual cells. Luciferase assay with reporter constructs confirmed that the suppression of PLA2G4B occurs through binding of miR-338 to the 3UTR of PLA2G4B. Interestingly, the expression of Dicer, a key miRNA-processing enzyme, was markedly decreased at term, particularly with labour in the chorioamniotic membranes. Collectively, the novel findings reported herein strongly suggest that post-transcriptional regulation of genes by miRNAs, coupled with the changes of miRNA processing machinery in the chorioamniotic membranes, plays a role in pregnancy and parturition. Furthermore, the expression level of Dicer in the chorioamniotic membranes dichotomizes pathological preterm labour and physiological spontaneous labour at term.

Infarct size by contrast enhanced cardiac magnetic resonance is a stronger predictor of outcomes than left ventricular ejection fraction or end-systolic volume index: prospective cohort study

OBJECTIVES

Ejection fraction (EF) and end-systolic volume index (ESVI) are established predictors of outcomes following ST-segment elevation myocardial infarction (STEMI). We sought to assess the relative impact of infarct size, EF and ESVI on clinical outcomes and left ventricular (LV) remodelling.

DESIGN

Prospective cohort study.

SETTING

Academic hospital in Chicago, USA.

PATIENTS

122 patients with STEMI following acute percutaneous reperfusion.

MAIN OUTCOME MEASURES

Death, recurrent myocardial infarction (MI) and heart failure.

METHODS

Cardiac magnetic resonance imaging was obtained within 1 week following STEMI in 122 subjects. ESVI, EF and infarct size were tested for the association with outcomes over 2 years in 113 subjects, and a repeat study was obtained 4 months later to assess LV remodelling in 91 subjects.

RESULTS

Acute infarct size correlated linearly with the initial ESVI (r = 0.69, p<0.001), end-diastolic volume index (EDVI) (r = 0.42, p<0.001) and EF (r = -0.75, p<0.001). All were independently associated with outcomes (one death, one recurrent MI and 16 heart failure admissions). However, infarct size was the only significant predictor of adverse outcomes (p<0.05) by multivariate analysis. The smallest infarct size tertile had an increased EF (49% (SD 8%) to 53% (6%); p = 0.002) and unchanged EDVI (p = 0.7). In contrast, subjects with the largest infarct tertile also had improved EF (32% (9%) to 36% (11%); p = 0.002) at the expense of a dramatic increase in EDVI (86 (19) to 95 (21) ml/m(2); p = 0.005).

CONCLUSIONS

Infarct size, EF and ESVI can predict the development of future cardiac events. Acute infarct size, which is independent of LV stunning and loading, directly relates to LV remodelling and is a stronger predictor of future events than measures of LV systolic performance.

Consistency of subjective responses to imagery-induced tobacco craving over multiple sessions

Although studies have demonstrated the validity of imagery procedures to elicit tobacco craving responses in single sessions, few studies have examined the consistency of responding in the same individuals over multiple experimental sessions. In this study, nondeprived smokers were presented with a randomized series of imagery scripts that varied in the intensity of smoking-urge content. At each of five sessions spaced over several weeks, participants were exposed to six imagery trials (two each of no-, low-, and high-intensity imagery scripts). After each trial, participants completed subjective measures of tobacco craving and mood. Ratings of craving and negative mood significantly increased as a function of smoking-urge intensity, which was consistent across the five sessions. Further, significant intraclass correlations indicated that craving and mood responses were highly reliable over the five sessions, as well as across two, three, and four sessions. These results have practical implications for examining individual differences in sensitivity to smoking cues and for studies involving repeated measurement of elicited craving over time.

Pharmacokinetic and pharmacodynamic consequences of inhibition of terazosin metabolism via CYP3A1 and/or 3A2 by DA-8159, an erectogenic, in rats

BACKGROUND AND PURPOSE

Recently, orthostatic hypotension was observed in patients with benign prostatic hyperplasia who are taking vardenafil (a PDE 5 inhibitor) and terazosin (a long acting alpha blocker). Therefore, this study was performed with DA-8159 (a long acting PDE 5 inhibitor) and terazosin in rats to find whether or not pharmacokinetic and pharmacodynamic interactions between the two drugs were observed.

EXPERIMENTAL APPROACH

Pharmacokinetic and pharmacodynamic (changes in blood pressure) interactions between DA-8159 and terazosin were evaluated after simultaneous i.v. and p.o. administration of DA-8159 (30 mg kg(-1)) and terazosin (5 mg kg(-1)) to male Sprague-Dawley rats.

KEY RESULTS

After simultaneous i.v. and p.o. administration of terazosin and DA-8159, the total area under the plasma concentration-time curve from time zero to time infinity (AUC) of terazosin became significantly greater (57.4 and 75.4% increase for i.v. and p.o. administration, respectively) than those of without DA-8159. The blood pressure dropping effect was considerable after simultaneous p.o. administration of DA-8159 and terazosin compared with each drug alone.

CONCLUSIONS AND IMPLICATIONS

The significantly greater AUC of terazosin after both simultaneous i.v. and p.o. administration of both drugs could be due to the hepatic (both i.v. and p.o.) and intestinal (p.o.) inhibition of the metabolism of terazosin via CYP3A1 and/or 3A2 by DA-8159, since both DA-8159 and terazosin are metabolized via CYP3A1 and/or 3A2 in rats. The blood pressure lowering effect after simultaneous p.o. administration of both drugs could be due to significant increase in plasma concentrations of terazosin.

MEG reveals different contributions of somatomotor cortex and cerebellum to simple reaction time after temporally structured cues

Magnetoencephalography (MEG) was used to measure brain activity while participants performed a simple reaction to targets after either a random interval (uncued targets) or a series of isochronous warning stimuli with 200-ms intervals that acted as a countdown. Targets could arrive "on time" or "early" relative to the preceding warning stimuli. Cerebellar activity before any stimulus onset predicted uncued simple reaction time. Onset of activity in somatomotor cortex relative to the target predicted reaction time after two warning stimuli when the target arrived on time or early. After three warning stimuli, when the target arrived on time and was certain to occur, prestimulus cerebellar activity and somatomotor onset were significant predictors of reaction time. When the target arrived early after three warning stimuli, prestimulus cerebellar and cingulate activity were predictive. The cerebellar results may reflect a number of possible factors, including a role in timing, response readiness, prediction and attention.

MTB, the murine homolog of condensin II subunit CAP-G2, represses transcription and promotes erythroid cell differentiation

Chromosome condensation is essential for proper segregation of duplicated sister chromatids in mitosis. Mammalian erythroid maturation is also associated with gradual nuclear condensation. However, few proteins that are directly involved in chromosome condensation during erythropoiesis have been identified. In this report, we show that MTB (more than blood), which was initially isolated in a yeast two-hybrid screen for proteins that interact with the basic helix-loop-helix (bHLH) protein stem cell leukemia (SCL), and later identified as the murine homolog of the condensin II subunit CAP-G2, participates in erythroid cell development. MTB interacts with SCL and another hematopoietic bHLH protein, E12, and is recruited to the nucleus by SCL and E12. In addition, MTB can repress SCL/E12-mediated transcriptional activation. Consistent with the model that MTB may function together with SCL/E12 heterodimer during erythroid cell development, MTB is highly expressed in the erythroid lineage and is upregulated upon erythroid differentiation. Moreover, overexpression of MTB promotes the terminal differentiation of the murine erythroleukemia erythroid cell line. Together, these findings demonstrate that the condensin II subunit MTB/mCAP-G2 plays a novel function during erythropoiesis and suggest that key hematopoietic transcription factors such as SCL and E12 may regulate the terminal differentiation of hematopoietic cells through the interaction with condensin complexes.

Chronometric evidence for entrained attention

Recent theories of dynamic attention have renewed the interest in temporal context as a determinant of attention. The mechanism of dynamic attention remains unclear, and both stochastic time perception processes and deterministic oscillators are possible. The results of Experiment 1 demonstrate that attention can be guided by isochronous series of warning stimuli and that elapsed time cannot fully account for this effect. Experiment 2 indicates that temporal structure can be used over a limited range of time. The results of Experiment 3 indicate that temporal pattern, rather than variability, is a determinant of temporally focused attention. The results of Experiment 4 demonstrate that a coupled oscillator is a better predictor of reaction time than a stochastic timing mechanism is, under certain assumptions.

Neurophysiological assessment of lower-limb voluntary control in incomplete spinal cord injury

STUDY DESIGN

Cross-sectional retrospective study of a neurophysiological method of voluntary motor control characterization.

OBJECTIVES

This study was undertaken to validate the surface electromyography (sEMG)-based voluntary response index (VRI) as an objective, quantitative, laboratory measure of spinal cord injury severity in terms of voluntary motor control disruption.

SETTING

VA Medical Centers in Houston and Dallas Texas, USA.

METHODS

A total of 67 subjects with incomplete spinal cord injury (iSCI), American Spinal Injury Association Impairment Scale (AIS)-C (n = 32) and -D (n = 35) were studied. sEMG recorded during a standardized protocol including eight lower-limb voluntary motor tasks was analyzed using the VRI method that relates multi-muscle activation patterns of SCI persons to those of healthy-subject prototypes (n = 15). The VRI is composed of a measure of the amount of the sEMG activity (magnitude) and the distribution of activity across muscle groups compared to that of healthy subjects for each motor task (similarity index, SI). These resulting VRI components, normalized magnitude and SI, were compared to AIS clinical findings in this study. Receiver operating characteristic analysis was performed to determine the SI values best separating AIS-C and AIS-D subjects.

RESULTS

Magnitude and SI for AIS-C subjects had mean values of 0.27 +/- 0.32 and 0.65 +/- 0.21, respectively. Both parameters were significantly larger in the AIS-D subjects (0.78 +/- 0.43 and 0.93 +/- 0.06), respectively (P < 0.01). An SI value of 0.85 was found to separate AIS-C and AIS-D groups with a sensitivity of 0.89 and a specificity of 0.81. Further, the VRI of each leg strongly correlated with the respective AIS motor score (0.80, r < 0.01).

CONCLUSIONS

In the domains of voluntary motor control, the sEMG-based VRI demonstrated adequate face validity and sensitivity to injury severity as currently measured by the AIS.

SPONSORSHIP

Veterans Affairs Medical Center.

Neurophysiological examination of the corticospinal system and voluntary motor control in motor-incomplete human spinal cord injury

This study employed neurophysiological methods to relate the condition of the corticospinal system with the voluntary control of lower-limb muscles in persons with motor-incomplete spinal cord injury. It consisted of two phases. In a group of ten healthy subjects, single and paired transcranial magnetic stimulation (TMS) of the motor cortex was used to study the behavior of the resulting motor evoked potentials (MEP) in lower-limb muscles. Interstimulus intervals (ISIs) of 15-100 ms were examined for augmentation of test MEPs by threshold or subthreshold conditioning stimuli. The second phase of this study examined eight incomplete spinal cord injured (iSCI) subjects, American Spinal Injury Association Impairment Scale C (n = 5) and D (n = 3) in whom voluntary motor control was quantified using the surface EMG (sEMG) based Voluntary Response Index (VRI). The VRI is calculated to characterize relative output patterns across ten lower-limb muscles recorded during a standard protocol of elementary voluntary motor tasks. VRI components were calculated by comparing the distribution of sEMG in iSCI subjects with prototype patterns collected from 15 healthy subjects using the same rigidly administered protocol, The resulting similarity index (SI) and magnitude values provided the measure of voluntary motor control. Corticospinal system connections were characterized by the thresholds for MEPs in key muscles. Key muscles were those that function as the prime-movers, or agonists for the voluntary movements from which the VRI data were calculated. Results include healthy-subject data that showed significant increases in conditioned MEP responses with paired stimuli of 15-50 ms ISI. Stimulus pairs of 75 and 100 ms showed no increase in MEP peak amplitude over that of the single-pulse conditioning stimulus alone, usually no response. For the iSCI subjects, 42% of the agonists responded to single-pulse TMS and 25% required paired-pulse TMS to produce an MEP. American Spinal Injury Association Impairment Scale component motor scores for agonist muscles, Quadriceps, Tibialis Anterior, and Triceps Surae, were significantly lower where MEPs could not be obtained (p < 0.05). VRI values were also significantly lower for motor tasks with agonists that had no resting MEP (p < 0.01). Therefore, the presence of a demonstrable connection between the motor cortex and spinal motor neurons in persons with SCI was related to the quality of post-injury voluntary motor control as assessed by the VRI.

Toward an objective interpretation of surface EMG patterns: a voluntary response index (VRI)

Individuals with incomplete spinal cord injuries (SCI) retain varying degrees of voluntary motor control. The complexity of the motor control system and the nature of the recording biophysics have inhibited efforts to develop objective measures of voluntary motor control. This paper proposes the definition and use of a voluntary response index (VRI) calculated from quantitative analysis of surface electromyographic (sEMG) data recorded during defined voluntary movement as a sensitive measure of voluntary motor control in such individuals. The VRI is comprised of two numeric values, one derived from the total muscle activity recorded for the voluntary motor task (magnitude), and the other from the sEMG distribution across the recorded muscles (similarity index (SI)). Calculated as a vector, the distribution of sEMG from the test subject is compared to the average vector calculated from sEMG recordings of the same motor task from 10 neurologically intact subjects in a protocol called brain motor control assessment (BMCA). To evaluate the stability of the VRI, a group of five healthy subjects were individually compared to the prototype, average healthy-subject vectors for all of the maneuvers. To evaluate the sensitivity of this method, the VRI was obtained from two SCI subjects participating in other research studies. One was undergoing supported treadmill ambulation training, and the other a controlled withdrawal of anti-spasticity medications. The supported treadmill training patient's VRI, calculated from pre- and post-training BMCA recordings, reflected the qualitative changes in sEMG patterns and functional improvement of motor control. The VRI of the patient followed by serial BMCA during medication withdrawal also reflected changes in the motor control as a result of changes in anti-spasticity medication. To validate this index for clinical use, serial studies using larger numbers of subjects with compromised motor control should be performed.