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1.
PLoS Pathog ; 20(4): e1012124, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38635841

RESUMO

Mycobacterium tuberculosis (M. tb), the causative agent of tuberculosis (TB), is a leading global cause of death from infectious disease. Biofilms are increasingly recognized as a relevant growth form during M. tb infection and may impede treatment by enabling bacterial drug and immune tolerance. M. tb has a complicated regulatory network that has been well-characterized for many relevant disease states, including dormancy and hypoxia. However, despite its importance, our knowledge of the genes and pathways involved in biofilm formation is limited. Here we characterize the biofilm transcriptomes of fully virulent clinical isolates and find that the regulatory systems underlying biofilm growth vary widely between strains and are also distinct from regulatory programs associated with other environmental cues. We used experimental evolution to investigate changes to the transcriptome during adaptation to biofilm growth and found that the application of a uniform selection pressure resulted in loss of strain-to-strain variation in gene expression, resulting in a more uniform biofilm transcriptome. The adaptive trajectories of transcriptomes were shaped by the genetic background of the M. tb population leading to convergence on a sub-lineage specific transcriptome. We identified widespread upregulation of non-coding RNA (ncRNA) as a common feature of the biofilm transcriptome and hypothesize that ncRNA function in genome-wide modulation of gene expression, thereby facilitating rapid regulatory responses to new environments. These results reveal a new facet of the M. tb regulatory system and provide valuable insight into how M. tb adapts to new environments.


Assuntos
Biofilmes , Regulação Bacteriana da Expressão Gênica , Mycobacterium tuberculosis , Transcriptoma , Biofilmes/crescimento & desenvolvimento , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Adaptação Fisiológica/genética , Humanos , Tuberculose/microbiologia , Tuberculose/genética
2.
Tob Control ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38071523

RESUMO

INTRODUCTION: The USA and New Zealand have sought to establish a product standard to set a maximum nicotine level for cigarettes to reduce their addictiveness. This study examined support for very low nicotine cigarettes (VLNCs) in Australia, Canada, England and the USA between 2016 and 2020. METHODS: Repeated cross-sectional data were analysed from participants who currently smoke, formerly smoked or vaped and/or currently vape in the 2016 (n=11 150) and/or 2020 (n=5432) International Tobacco Control (ITC) Four Country Smoking and Vaping Survey. Respondents were asked if they would support a law that reduces the amount of nicotine in cigarettes to make them less addictive. Adjusted and weighted logistic regression analyses estimated the prevalence and predictors of support, such as country, age, sex, education, income, race and smoking/vaping status for VLNCs (support vs oppose/do not know). RESULTS: A majority of respondents supported a VLNC law, with support highest in Canada (69%; 2016 and 2020 combined), followed by England (61%), Australia (60%) and the USA (58%). Overall, support decreased from 62% in 2016 to 59% in 2020 (p=0.004), which did not differ by country. Levels of support differed by smoking/vaping status, where those who exclusively smoked daily showed the lowest level of support (59%) and those who exclusively vaped non-daily had the highest level of support (72%). CONCLUSION: More than half of respondents in all four countries-including those who smoked daily-supported a hypothetical VLNC standard to render cigarettes less addictive. It is important to examine if support is sustained after policies are implemented.

3.
Stat Med ; 41(12): 2276-2290, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35194829

RESUMO

Individual participant data meta-analysis is a frequently used method to combine and contrast data from multiple independent studies. Bayesian hierarchical models are increasingly used to appropriately take into account potential heterogeneity between studies. In this paper, we propose a Bayesian hierarchical model for individual participant data generated from the Cigarette Purchase Task (CPT). Data from the CPT details how demand for cigarettes varies as a function of price, which is usually described as an exponential demand curve. As opposed to the conventional random-effects meta-analysis methods, Bayesian hierarchical models are able to estimate both the study-specific and population-level parameters simultaneously without relying on the normality assumptions. We applied the proposed model to a meta-analysis with baseline CPT data from six studies and compared the results from the proposed model and a two-step conventional random-effects meta-analysis approach. We conducted extensive simulation studies to investigate the performance of the proposed approach and discussed the benefits of using the Bayesian hierarchical model for individual participant data meta-analysis of demand curves.


Assuntos
Produtos do Tabaco , Teorema de Bayes , Análise de Dados , Humanos
4.
Neurourol Urodyn ; 41(8): 1731-1738, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35900298

RESUMO

AIMS: The basic evaluation or percutaneous nerve evaluation (PNE) is a method to assess pre-implantation therapeutic response in patients considering sacral neuromodulation for the treatment of refractory overactive bladder. A new PNE lead with a more robust design and greater distensibility designed to reduce the possibility of lead migration has recently been introduced to the market. The aim of this prospective, multicenter, global, postmarket study was to evaluate the clinical performance and safety of the new InterStim PNE lead with the foramen needle. METHODS: Patients with overactive bladder were enrolled in this study. The primary objective of this study was to determine the proportion of subjects who demonstrated motor or sensory response(s) during lead placement using the InterStim PNE lead. Additional measures included the Patient Global Impression of Improvement (PGI-I), patient satisfaction at the end of therapy evaluation, and change in bladder symptoms from baseline to the end of therapy evaluation (1-week follow-up visit). RESULTS: One-hundred and ten subjects met the inclusion and exclusion criteria and underwent a lead implant procedure. Of those, 108 had a successful procedure and 107 completed the 1-week follow-up visit. Ninety-nine percent of subjects (109/110) had a motor or sensory response during needle placement (95% confidence interval [CI]: 95%-100%) and 97% of subjects (107/110) had a motor or sensory response during lead placement (95% CI: 92%-99%). The majority of subjects (88%, 95/108) reported their bladder condition was better at the follow-up visit compared to before the PNE implant procedure, as reported in PGI-I. Subjects reported being satisfied with how the therapy impacted their voiding symptoms (82%, 88/108) and that they would recommend this therapy (87%, 94/108) to other patients. Symptom improvement was demonstrated with urinary urge incontinence subjects having an average of 4.2 ± 3.4 urinary incontinence episodes/day at baseline and 2.2 ± 2.5 at follow-up, and urinary frequency subjects having an average of 12.5 ± 4.4 voids/day at baseline and 10.5 ± 4.3 voids/day at follow-up. Lead removal was deemed to be easy and safe by the implanting physician, with a total of three adverse device effects in 3/110 subjects. No event was categorized as serious and all were resolved without sequelae. CONCLUSIONS: The updated InterStim PNE lead with a more robust design and greater distensibility designed to reduce migration was shown to have a high rate of motor or sensory response during lead placement. Furthermore, subjects reported high rates of global improvements and amelioration of symptoms, and the lead was easy to remove with minimal morbidity.


Assuntos
Terapia por Estimulação Elétrica , Bexiga Urinária Hiperativa , Humanos , Bexiga Urinária Hiperativa/diagnóstico , Terapia por Estimulação Elétrica/métodos , Estudos Prospectivos , Resultado do Tratamento , Incontinência Urinária de Urgência/terapia
5.
Nicotine Tob Res ; 24(1): 3-9, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34270729

RESUMO

The introduction of alternative nicotine and tobacco products (such as e-cigarettes, heat-not-burn devices, nicotine pouches) warrants an updated framework from which to conceptualize tobacco use disorder (TUD). The following review provides considerations for TUD within the context of novel products. Historically, the tobacco industry falsely claimed that cigarettes were not addictive or harmful and that those who smoked simply chose to do so. This generated an inaccurate lay perception that smoking is a free or informed choice. Research on nicotine pharmacology demonstrates the powerful addictive potential of nicotine, which is shaped by dose, speed of delivery, and other constituents generated. In addition, non-pharmacologic reinforcers motivate and maintain tobacco use behaviors for both traditional cigarettes and novel products. The negative consequences of combustible tobacco use are well known; however, these outcomes may differ for alternative products. Strategies used for combustible product cessation may be adapted for novel products, and treatment recommendations for TUD should be made within the context of a harm reduction framework wherein alternative product use may be the desired outcome. Providers must therefore be willing to modify their perceptions of products and treatment recommendations accordingly. Better public health outcomes are accomplished through promotion of abstinence from combustible smoking. For those who cannot wean from nicotine entirely, switching to less risky modes of delivery might be a secondary goal, with an eventual aim of stopping use of the alternative product. Implications: Given the advent of novel, alternative tobacco products, tobacco use disorder (TUD) must be conceptualized within a contemporary framework that includes harm reduction and alternative outcomes. The unique contributions of nicotine pharmacology, non-pharmacologic reinforcers, and consequences of use can be used to inform treatments for TUD with the ultimate goal of improving the health of individuals who use tobacco.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Tabagismo , Humanos , Dispositivos para o Abandono do Uso de Tabaco , Tabagismo/terapia
6.
Nicotine Tob Res ; 24(11): 1798-1802, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-35524988

RESUMO

INTRODUCTION: In response to reducing cigarette nicotine content, people who smoke could attempt to compensate by using more cigarettes or by puffing on individual cigarettes with greater intensity. Such behaviors may be especially likely under conditions where normal nicotine content (NNC) cigarettes are not readily accessible. The current within-subject, residential study investigated whether puffing intensity increased with very low nicotine content (VLNC) cigarette use, relative to NNC cigarette use, when no other nicotine products were available. AIMS AND METHODS: Sixteen adults who smoke daily completed two four-night hotel stays in Charleston, South Carolina (United States) in 2018 during which only NNC or only VLNC cigarettes were accessible. We collected the filters from all smoked cigarettes and measured the deposited solanesol to estimate mouth-level nicotine delivery per cigarette. These estimates were averaged within and across participants, per each 24-h period. We then compared the ratio of participant-smoked VLNC and NNC cigarette mouth-level nicotine with the ratio yielded by cigarette smoking machines (when puffing intensity is constant). RESULTS: Average mouth-level nicotine estimates from cigarettes smoked during the hotel stays indicate participants puffed VLNC cigarettes with greater intensity than NNC cigarettes in each respective 24-h period. However, this effect diminished over time (p < .001). Specifically, VLNC puffing intensity was 40.0% (95% CI: 29.9, 53.0) greater than NNC puffing intensity in the first period, and 16.1% (95% CI: 6.9, 26.0) greater in the fourth period. CONCLUSION: Average puffing intensity per cigarette was elevated with exclusive VLNC cigarette use, but the extent of this effect declined across four days. IMPLICATIONS: In an environment where no other sources of nicotine are available, people who smoke daily may initially attempt to compensate for cigarette nicotine reduction by puffing on individual cigarettes with greater intensity. Ultimately, the compensatory behavior changes required to achieve usual nicotine intake from VLNC cigarettes are drastic and unrealistic. Accordingly, people are unlikely to sustain attempts to compensate for very low cigarette nicotine content.


Assuntos
Fumar Cigarros , Abandono do Hábito de Fumar , Produtos do Tabaco , Adulto , Humanos , Nicotina , Pesquisa
7.
Cell Mol Life Sci ; 79(1): 37, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-34971428

RESUMO

The roles of nitric oxide (NO) and endothelial NO synthase (eNOS) in the regulation of angiogenesis are well documented. However, the involvement of eNOS in the sprouting of endothelial tip-cells at the vascular front during sprouting angiogenesis remains poorly defined. In this study, we show that downregulation of eNOS markedly inhibits VEGF-stimulated migration of endothelial cells but increases their polarization, as evidenced by the reorientation of the Golgi in migrating monolayers and by the fewer filopodia on tip cells at ends of sprouts in endothelial cell spheroids. The effect of eNOS inhibition on EC polarization was prevented in Par3-depleted cells. Importantly, downregulation of eNOS increased the expression of polarity genes, such as PARD3B, PARD6A, PARD6B, PKCΖ, TJP3, and CRB1 in endothelial cells. In retinas of eNOS knockout mice, vascular development is retarded with decreased vessel density and vascular branching. Furthermore, tip cells at the extremities of the vascular front have a marked reduction in the number of filopodia per cell and are more oriented. In a model of oxygen-induced retinopathy (OIR), eNOS deficient mice are protected during the initial vaso-obliterative phase, have reduced pathological neovascularization, and retinal endothelial tip cells have fewer filopodia. Single-cell RNA sequencing of endothelial cells from OIR retinas revealed enrichment of genes related to cell polarity in the endothelial tip-cell subtype of eNOS deficient mice. These results indicate that inhibition of eNOS alters the polarity program of endothelial cells, which increases cell polarization, regulates sprouting angiogenesis and normalizes pathological neovascularization during retinopathy.


Assuntos
Neovascularização Patológica , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/fisiologia , Retina/metabolismo , Neovascularização Retiniana , Vasos Retinianos , Animais , Bovinos , Linhagem Celular , Movimento Celular , Polaridade Celular , Células Endoteliais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Retina/citologia , Retina/patologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Vasos Retinianos/citologia , Vasos Retinianos/patologia
8.
BMC Pulm Med ; 22(1): 129, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35387636

RESUMO

INTRODUCTION: The battery-operated hand-held fan ('fan') is an inexpensive and portable non-pharmacological intervention for chronic breathlessness. Evidence from randomised controlled trials suggests the fan reduces breathlessness intensity and improves physical activity in patients with a range of advanced chronic conditions. Qualitative data from these trials suggests the fan may also reduce anxiety and improve daily functioning for many patients. This study aimed to explore barriers and facilitators to the fan's implementation in specialist respiratory care as a non-pharmacological intervention for chronic breathlessness in patients with chronic obstructive pulmonary disease (COPD). METHODS: A qualitative approach was taken, using focus groups. Participants were clinicians from any discipline working in specialist respiratory care at two hospitals. Questions asked about current fan-related practice and perceptions regarding benefits, harms and mechanisms, and factors influencing its implementation. Analysis used a mixed inductive/deductive approach. RESULTS: Forty-nine participants from nursing (n = 30), medical (n = 13) and allied health (n = 6) disciplines participated across 9 focus groups. The most influential facilitator was a belief that the fan's benefits outweighed disadvantages. Clinicians' beliefs about the fan's mechanisms determined which patient sub-groups they targeted, for example anxious or palliative/end-stage patients. Barriers to implementation included a lack of clarity about whose role it was to implement the fan, what advice to provide patients, and limited access to fans in hospitals. Few clinicians implemented the fan for acute-on-chronic breathlessness or in combination with other interventions. CONCLUSION: Implementation of the fan in specialist respiratory care may require service- and clinician-level interventions to ensure it is routinely recommended as a first-line intervention for chronic breathlessness in patients for whom this symptom is of concern, regardless of COPD stage.


Assuntos
Dispneia , Doença Pulmonar Obstrutiva Crônica , Doença Crônica , Dispneia/etiologia , Dispneia/terapia , Humanos , Cuidados Paliativos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia , Pesquisa Qualitativa
9.
Prev Med ; 149: 106600, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33957152

RESUMO

As governments consider policy action to reduce smoking, a key factor in creating political will is the level of public support, particularly among smokers who are most affected by the policies. The goal of this paper is to assess and compare the level of support in Canada, the United States, England, and Australia for five smoking control policies: 1) banning menthol in cigarettes, 2) banning cigarette additives, 3) reducing nicotine in cigarettes to make them less addictive, 4) raising the minimum age to purchase cigarettes to 21 years and older, and 5) requiring pictorial warning labels on cigarette packs (examined in the US only). Data for these analyses come from 8165 daily cigarette smokers who responded to the 2016 International Tobacco Control Four Country Smoking and Vaping Survey. In all countries, the highest level of support was for raising the legal age for purchase to 21 years and older (62-70%) and reducing the nicotine content of cigarettes to make them less addictive (57-70%). Smokers who were less dependent on cigarettes and those expressing interest in quitting were more likely to support all policies. When asked how they would respond to a nicotine reduction policy, the most common response given was to try the non-nicotine cigarettes to see how they liked them (42-48%), with the next most common response being to quit smoking entirely (16-24%). The high level of support for these proposed policies among daily smokers provides important evidence for policymakers to counteract claims that such policies would be unpopular.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Austrália , Canadá , Estudos Transversais , Inglaterra , Humanos , Política Pública , Fumantes , Fumar , Nicotiana , Estados Unidos
10.
Nicotine Tob Res ; 23(3): 438-446, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-32710538

RESUMO

INTRODUCTION: The U.S. Food and Drug Administration (FDA) has proposed lowering the nicotine content of cigarettes to a minimally addictive level to increase smoking cessation and reduce initiation. This study has two aims: (1) to determine when cigarette manufacturers had the technical capability to reduce cigarette nicotine content and (2) to estimate the lost public health benefits of implementing a standard in 1965, 1975, or 1985. METHODS: To determine the technical capability of cigarette companies, we reviewed public patents and internal cigarette company business records using the Truth Tobacco Industry Documents. To evaluate the impact of a very low nicotine content cigarette (VLNC) standard on smoking attributable deaths (SADs) and life-years lost (LYLs), we applied a validated (CISNET) model that uses past smoking data, along with estimates of the potential impact of VLNCs derived from expert elicitation. RESULTS: Cigarette manufacturers recognized that cigarettes were deadly and addictive before 1964. Manufacturers have had the technical capability to lower cigarette nicotine content for decades. Our model projected that a standard implemented in 1965 could have averted 21 million SADs (54% reduction) and 272 million LYLs (64% reduction) from 1965 to 2064, a standard implemented in 1975 could have averted 18.9 million SADs and 245.4 million LYLs from 1975 to 2074, and a standard implemented in 1985 could have averted 16.3 million SADs and 211.5 million LYLs from 1985 to 2084. CONCLUSIONS: Millions of premature deaths could have been averted if companies had only sold VLNCs decades ago. FDA should act immediately to implement a VLNC standard. IMPLICATIONS: Prior research has shown that a mandated reduction in the nicotine content of cigarettes could reduce the prevalence of smoking and improve public health. Here we report that cigarette manufacturers have had the ability to voluntarily implement such a standard for decades. We use a well-validated model to demonstrate that millions of smoking attributable deaths and life-years lost would have been averted if the industry had implemented such a standard.


Assuntos
Nicotina/análise , Saúde Pública , Abandono do Hábito de Fumar/estatística & dados numéricos , Indústria do Tabaco/normas , Fumar Tabaco/epidemiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/química , Prevalência , Estados Unidos/epidemiologia
11.
Nicotine Tob Res ; 23(6): 983-991, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33249458

RESUMO

INTRODUCTION: Medication sampling is a clinically useful tool to engage smokers in the quitting process. Whether varenicline is suitable for sampling purposes is unclear. The purpose of this study was to examine the feasibility, uptake, and preliminary outcomes of varenicline sampling. METHODS: Smokers (N = 99), both motivated to quit and not, were recruited and randomized to varenicline sampling versus not, with 12 week follow-up. The intervention consisted of mailing one-time samples of varenicline (lasting 2-4 wks), with minimally suggestive guidance on use. RESULTS: Uptake of varenicline was strong, at 2 weeks (54% any use, 66% daily use) and 4 weeks (38%, 46%), with 58% of medication users seeking additional medication. Most users followed conventional titration patterns, self-titrating from 0.5 mg to 2 mg. Relative to control, varenicline sampling increased motivation (p = 0.006) and confidence to quit (p = 0.02), and decreased cigarette smoking (p = 0.02). Smokers receiving varenicline samples were significantly more likely to achieve 50% reduction in cigarettes per day (CPD), both immediately following the sampling exercise (Adjusted Odds Ratio [AOR] = 4.12; 95% CI: 1.39 to 12.17) and at final follow-up (AOR = 4.50; 95% CI: 1.56 to 13.01). Though cessation outcomes were not statistically significant, there was a 1.5 to 3-fold increase in quit attempts and abstinence from varenicline sampling throughout follow-up. These outcomes were comparable among smokers motivated to quit and not. CONCLUSIONS: Unguided, user-driven sampling of varenicline sampling is a concrete behavioral exercise that is feasible to do and seems to suggest clinical utility. Sampling is a pragmatic clinical approach to engage more smokers in quitting. IMPLICATIONS: Use of evidence-based pharmacotherapies for smoking cessation is low. Medication sampling is a pragmatic behavioral exercise that allows smokers to experience the benefits of using them, while promoting positive downstream effects towards quitting. While previous studies have shown that nicotine replacement therapy (NRT) sampling is viable and effective, whether this extends to varenicline is unclear. Results from this trial demonstrate that varenicline sampling is feasible, safe, and suggestive of clinically important steps toward quitting, deserving of a larger trial. CLINICAL TRIAL REGISTRATION: NCT #03742154.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Adulto , Feminino , Humanos , Masculino , Projetos Piloto , Dispositivos para o Abandono do Uso de Tabaco , Vareniclina/uso terapêutico
12.
Nicotine Tob Res ; 23(9): 1559-1566, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-33754156

RESUMO

INTRODUCTION: As the FDA works to determine whether a nicotine reduction policy would benefit public health, one key question is whether to mandate an immediate or gradual reduction in nicotine levels in cigarettes. The aim of this study was to determine whether the effects of gradual versus immediate nicotine reduction on cigarettes per day (CPD), total nicotine equivalents, and subjective responses differed in younger adults versus older adults. METHODS: Using data from a recent randomized trial conducted in the United States (N = 1250) that switched smokers over a 20-week period to very low nicotine content (VLNC) cigarettes either immediately, gradually (via monthly reductions in nicotine content), or not at all (control condition, normal nicotine content research cigarette), we analyzed the moderating effect of age (age 18-24 or 25+). RESULTS: For both age groups, CPD in the immediate condition was significantly lower relative to gradual condition (estimated mean difference of 6.3 CPD in young adults, 5.2 CPD in older adults; p's < .05). Younger and older adults in the immediate and gradual reduction conditions had lower total nicotine equivalents at Week 20 (all p's < .05) than those in the control condition; age group did not moderate this effect. Positive subjective responses to cigarettes were lower among young adults relative to older adults in the immediate condition. CONCLUSIONS: These results indicate that an immediate reduction in nicotine would result in beneficial effects in both young and older adults. Young adults show less positive subjective effects of smoking following switching to VLNC cigarettes relative to older adults. IMPLICATIONS: As researchers work to understand how a potential reduced-nicotine product standard for cigarettes may affect public health, one question is whether nicotine should be reduced immediately or gradually. This study demonstrates that both young and older adults who were switched immediately to the lowest content of nicotine smoked fewer CPD and had lower nicotine intake than those in the gradual condition. Furthermore, young adults appear to show lower positive subjective effects following switching to VLNC cigarettes relative to older adults. This is consistent with previous work demonstrating that young people appear to show lower abuse liability for VLNC cigarettes.


Assuntos
Abandono do Hábito de Fumar , Produtos do Tabaco , Adolescente , Adulto , Idoso , Humanos , Nicotina , Fumantes , Fumar , Estados Unidos , Adulto Jovem
13.
Clin Trials ; 18(1): 28-38, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32921152

RESUMO

INTRODUCTION: Participant noncompliance, in which participants do not follow their assigned treatment protocol, has long complicated the interpretation of randomized clinical trials. No gold standard has been identified for detecting noncompliance, but in some trials participants' biomarkers can provide objective information that suggests exposure to non-study treatments. However, existing methods are limited to retrospectively detecting noncompliance at a single time point based on a single biomarker measurement. We propose a novel method that can leverage participants' full biomarker history to detect noncompliance across multiple time points. Conditional on longitudinal biomarker data, our method can estimate the probability of compliance at (1) a single time point of the trial, (2) all time points, and (3) a future time point. METHODS: Across time points, we model the biomarker as a mixture density with (latent) components corresponding to longitudinal patterns of compliance. To estimate the mixture density, we fit mixed effects models for both compliance and the biomarker. We use the mixture density to derive compliance probabilities that condition on the longitudinal biomarker data. We evaluate our compliance probabilities by simulation and apply them to a trial in which current smokers were asked to only smoke low nicotine study cigarettes (Center for the Evaluation of Nicotine in Cigarettes Project 1 Study 2). In the simulation, we investigated three different effects of compliance on the biomarker, as well as the effect of misspecification of the covariance structures. We compared probability estimators (1) and (2) to those that ignore the longitudinal correlation in the data according to area under the receiver operating characteristic curve. We evaluated estimator (3) by plotting its calibration lines. For Center for the Evaluation of Nicotine in Cigarettes Project 1 Study 2, we compared estimators (1) and (3) to a probability estimator of compliance at the last time point that ignores the longitudinal correlation. RESULTS: In the simulation, for both compliance at the last time point and at all time points, conditioning on the longitudinal biomarker data uniformly raised area under the receiver operating characteristic curve across all three compliance effect scenarios. The gains in area under the receiver operating characteristic curve were smaller under misspecification. The calibration lines for the prediction of compliance closely followed 45°, though with additional variability under misspecification. For compliance at the last time point of Center for the Evaluation of Nicotine in Cigarettes Project 1 Study 2, conditioning on participants' full biomarker history boosted area under the receiver operating characteristic curve by three percentage points. The prediction probabilities somewhat accurately approximated the non-longitudinal compliance probabilities. DISCUSSION: Compared to existing methods that only use a single biomarker measurement, our method can account for the longitudinal correlation in the biomarker and compliance to more accurately identify noncompliant participants. Our method can also use participants' biomarker history to predict compliance at a future time point.


Assuntos
Cooperação do Paciente , Projetos de Pesquisa , Biomarcadores , Simulação por Computador , Humanos , Probabilidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
14.
J Community Health ; 46(1): 22-30, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32410089

RESUMO

The state of Alaska had a sharp increase in cases of primary and secondary syphilis among gay, bisexual, and other men who have sex with men (GBMSM) in 2018, centered in Anchorage. A rapid ethnographic assessment was conducted in October 2018 to examine contextual factors contributing to local increases in syphilis. The assessment team conducted qualitative interviews with 64 (N=49 interviews) key informants in Anchorage and Matanuska-Susitna Valley identified through the STD/HIV program at the Alaska Department of Health and Social Services, Division of Public Health (ADPH):  ADPH staff (n = 11; 22%) Medical Providers (n = 18; 37%), Community-Based Organizations/Partners (n = 9; 18%), and GBMSM Community Members (n = 11; 22%). This project was deemed exempt from IRB review. Primary factors affecting syphilis transmission, care, and treatment among GBMSM were: (1) Low awareness about the current syphilis outbreak and ambivalence about syphilis and other STIs; (2) Aspects of sexual partnering such as travel, tourism, and the use of online sites and apps to facilitate anonymous sex and multiple (both sequential/concurrent) partnering; (3) The synergistic effects of substance use, homelessness, and transactional sex; (4) Choosing condomless sex; and (5) Challenges accessing healthcare, including the ability to find appropriate and culturally competent care. Syphilis increases may have been influenced by factors which spanned multiple sectors of the Anchorage community, including individual behavior, community-level risk and protective factors, and use of and interactions with resources offered by ADPH, community-based organizations, and medical providers.


Assuntos
Homossexualidade Masculina/estatística & dados numéricos , Assunção de Riscos , Minorias Sexuais e de Gênero/estatística & dados numéricos , Sífilis/prevenção & controle , Sexo sem Proteção/estatística & dados numéricos , Adulto , Alaska , Humanos , Masculino , Prevalência , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Sífilis/epidemiologia
15.
Chron Respir Dis ; 18: 14799731211002241, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33739194

RESUMO

We performed a cross-sectional study within a specialised respiratory inpatient unit assessing 25 nurses' [85% female, 8.0 ± 7.9 (mean ± SD) years' experience in nursing] confidence in providing inhaler device education using a self-reported questionnaire, and their competency (% correct steps) in using eight different inhaler devices. Sixteen percent of participants were 'not confident' providing inhaler education, while 84% were 'moderately' or 'extremely' confident. The mean (±SD)% correct steps for all devices was 47 ± 17%. There was no correlation between % correct steps and nursing years (r = 0.21, p = 0.31), or 'confidence' with providing inhaler education (r = 0.02, p = 0.91) but % correct steps strongly correlated with number of individual device prescriptions within the hospital in the preceding year (r = 0.78, p = 0.039). Most respiratory nurses felt confident in teaching inhaler technique but their overall demonstrated ability to correctly use inhalers was poor, especially for less frequently prescribed devices within our hospital. Regular assessment and ongoing education on correct inhaler technique for respiratory nurses is necessary to optimise all device usage by nurses, irrespective of experience or confidence.


Assuntos
Enfermeiras e Enfermeiros , Doença Pulmonar Obstrutiva Crônica , Administração por Inalação , Estudos Transversais , Feminino , Humanos , Pacientes Internados , Masculino , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Inquéritos e Questionários
16.
Prev Med ; 136: 106096, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32320705

RESUMO

Cigarette smoking is increasingly concentrated among marginalized populations with limited access to evidence-based cessation treatment. This includes racial/ethnic minorities, lower income individuals, those with lower educational attainment, and residents of rural areas. To reach Healthy People 2020 objectives, successful cessation interventions must narrow these disparities. Nicotine replacement therapy (NRT) sampling is an easily translatable and scalable intervention that could enhance treatment access and thus narrow disparities. The present study examined individual-level demographic moderators of the impact of NRT sampling on cessation-related behaviors including: 1) use of a cessation medication, 2) making a 24-hour quit attempt, 3) floating abstinence, and 4) 7-day point prevalence abstinence at 6-months. Study participants included N = 1245 adult smokers enrolled in the Tobacco Intervention in Primary Care Treatment Opportunities for Providers (TIP TOP) study, a recently concluded large-scale clinical trial of NRT sampling relative to standard care within 22 primary care clinics across South Carolina. Generalized linear models examined individual-level demographic moderators of treatment effect. Results suggest that NRT sampling may be more effective among some of the most disadvantaged groups of smokers, including smokers with lower income and education, as well those who live in more rural areas. The effects of NRT sampling did not differ by race. In sum, NRT sampling is a low-cost, low-burden intervention that could be disseminated broadly to reach large numbers of smokers and potentially narrow cessation disparities.


Assuntos
Nicotiana , Abandono do Hábito de Fumar , Adulto , Humanos , Nicotina , South Carolina , Dispositivos para o Abandono do Uso de Tabaco
17.
Nicotine Tob Res ; 22(5): 791-797, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-31403695

RESUMO

INTRODUCTION: Electronic nicotine delivery systems (ENDS) vary on a wide range of characteristics that may affect reinforcement value and use. One characteristic is the ratio of two solvents commonly used in most e-liquids: propylene glycol (PG) and vegetable glycerin (VG). The goal of this study was to understand how PG/VG ratio affects subjective effects, reinforcement value, and tobacco use patterns among current smokers who try using ENDS. AIMS AND METHODS: Current smokers with minimal ENDS use history (n = 30) sampled, in a double-blind fashion, three different e-liquids that varied in PG/VG ratio (70/30, 50/50, 0/100) while holding constant other aspects of the e-liquid and ENDS. Participants tried each e-liquid before rating the subjective effects on a modified version of the Cigarette Evaluation Questionnaire. Reinforcement value was assessed using a preference task where participants chose between the three e-liquids. The impact of each e-liquid on cigarette reinforcement was assessed using a modified version of the Cigarette Purchase Task. Participants were randomly assigned to receive one e-liquid to take home for 1 week. RESULTS: PG/VG ratio had minimal impact on most of the tested outcomes. Participants rated the highest PG concentration as having a stronger "throat hit" than the other two. There was no significant difference between the number of participants who preferred each of the PG/VG ratios in the preference assessment. PG/VG ratio did not affect cigarette or ENDS use during the sampling week. CONCLUSIONS: These data suggest that PG/VG ratio has minimal impact on subjective effects and reinforcement value in ENDS naive current smokers. IMPLICATIONS: These data suggest that PG/VG ratio, within the range that is commonly used, has minimal impact on subjective effects, reinforcement value, or uptake in current smokers with minimal ENDS experience.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Glicerol/farmacologia , Propilenoglicol/farmacologia , Reforço Psicológico , Fumantes/psicologia , Verduras/química , Adulto , Comportamento do Consumidor , Método Duplo-Cego , Feminino , Humanos , Masculino , Solventes/farmacologia
18.
Nicotine Tob Res ; 22(2): 297-301, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30500925

RESUMO

INTRODUCTION: E-cigarettes have risen in prevalence in recent years, and most public health experts agree they deliver fewer toxicants than combustible tobacco products such as cigarettes. Thus, it is important to understand how use of e-cigarettes by current smokers impacts dependence on combustible cigarettes. METHODS: The present study is a secondary analysis of a randomized pilot trial of e-cigarette sampling. Nontreatment seeking current smokers were randomized in a 2:1 ratio to either receive or not receive a weekly supply of e-cigarettes for 3 weeks. Participants completed the Brief Wisconsin Inventory of Smoking Dependence Motives (WISDM) scale and the cigarette purchase task before and after the sampling period and at monthly follow-up visits for 3 months. RESULTS: Individuals assigned to receive an e-cigarette had significantly lower mean WISDM scores at the end of sampling and the end of the follow-up period compared with those in the control group. Both frequency of e-cigarette use as well as nicotine concentration of the e-cigarette given to smokers were significant predictors of changes in the mean WISDM score. E-cigarette sampling significantly reduced the demand parameter Omax, which measures the maximum amount of money participants estimate they would spend on cigarettes in a single day. CONCLUSIONS: These data suggest that current smokers who try using an e-cigarette may experience reductions in dependence on combustible cigarettes. IMPLICATIONS: The present analysis suggests that providing an e-cigarette to current cigarette smokers is likely to reduce cigarette dependence, especially if the e-cigarette delivers sufficient nicotine and is used frequently.


Assuntos
Fumar Cigarros/psicologia , Sistemas Eletrônicos de Liberação de Nicotina , Reforço Psicológico , Fumantes/psicologia , Vaping/psicologia , Adulto , Fumar Cigarros/epidemiologia , Feminino , Humanos , Masculino , Motivação/fisiologia , Projetos Piloto , Abandono do Hábito de Fumar/psicologia , Vaping/epidemiologia
19.
Nicotine Tob Res ; 22(8): 1294-1300, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31701153

RESUMO

INTRODUCTION: Smoking to reduce negative affect has been identified as a key motivational feature of tobacco use. Our recent work suggests that smoking very low nicotine content (VLNC) cigarettes reduces the relationship between negative affect and smoking behavior over a 6-week period. Here, we sought to extend our findings by evaluating whether a gradual or immediate approach to switching to VLNC cigarettes led to a differential reduction in the relationship between affect and smoking behavior over a longer (20-week) period. AIMS AND METHODS: Participants (n = 1250) were adult smokers from 10 US sites randomized to one of three groups: gradual nicotine reduction (15.5, 11.7, 5.2, 2.4, and 0.4 mg of nicotine per gram of tobacco [mg/g]), immediate nicotine reduction (0.4 mg/g), or standard nicotine content cigarettes (15.5 mg/g; control), for 20 weeks. We examined whether the relationship between affect-both negative and positive-and cigarettes per day differed as a function of reduction group. RESULTS: We found that both negative and positive affect were associated with cigarette consumption in the control group, but not in the gradual or immediate reduction groups across the 20 weeks of exposure. CONCLUSIONS: Our results extend previous findings that switching to VLNC cigarettes disrupts the relationship between affect and cigarette consumption by showing that either gradually or immediately reducing cigarette nicotine content achieves this disruption. These findings provide further evidence that switching to VLNC cigarettes reduces nicotine-related reinforcement of cigarette smoking. IMPLICATIONS: These findings support the notion that switching to very low nicotine content cigarettes reduces the association between affect and smoking behavior, and that either a gradual or immediate nicotine reduction approach achieves this reduction. This provides further evidence that switching to very low nicotine content cigarettes weakens reinforcement mechanisms associated with nicotine dependence.


Assuntos
Fumar Cigarros/psicologia , Retroalimentação , Nicotina/análise , Reforço Psicológico , Fumantes/psicologia , Fumar/psicologia , Tabagismo/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Fumar Cigarros/epidemiologia , Método Duplo-Cego , Emoções , Feminino , Humanos , Masculino , Motivação , Nicotina/administração & dosagem , Abandono do Hábito de Fumar/métodos , Produtos do Tabaco/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
20.
Nicotine Tob Res ; 21(Suppl 1): S16-S18, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31867654

RESUMO

The available research on switching from normal nicotine to very low nicotine content cigarettes shows minimal evidence of compensatory smoking. Mathematical estimations suggest that substantial compensation after switching to very low nicotine cigarettes would be impossible. It is likely that smokers who are unable to tolerate the extent of proposed nicotine reduction would switch to other sources of nicotine, rather than try to compensate by smoking more very low nicotine content cigarettes more intensely.


Assuntos
Nicotina , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Humanos
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