Trimodal single-cell profiling reveals a novel pediatric CD8αα+ T cell subset and broad age-related molecular reprogramming across the T cell compartment.

Age-associated changes in the T cell compartment are well described. However, limitations of current single-modal or bimodal single-cell assays, including flow cytometry, RNA-seq (RNA sequencing) and CITE-seq (cellular indexing of transcriptomes and epitopes by sequencing), have restricted our ability to deconvolve more complex cellular and molecular changes. Here, we profile >300,000 single T cells from healthy children (aged 11-13 years) and older adults (aged 55-65 years) by using the trimodal assay TEA-seq (single-cell analysis of mRNA transcripts, surface protein epitopes and chromatin accessibility), which revealed that molecular programming of T cell subsets shifts toward a more activated basal state with age. Naive CD4+ T cells, considered relatively resistant to aging, exhibited pronounced transcriptional and epigenetic reprogramming. Moreover, we discovered a novel CD8αα+ T cell subset lost with age that is epigenetically poised for rapid effector responses and has distinct inhibitory, costimulatory and tissue-homing properties. Together, these data reveal new insights into age-associated changes in the T cell compartment that may contribute to differential immune responses.

Perceptions of a reduced nicotine policy and predictors of policy support: A nationally representative U.S. survey.

BACKGROUND: The U.S. Food and Drug Administration is considering a policy to reduce nicotine in cigarettes to non-addictive levels. Although current evidence supports the public-health benefits of a reduced-nicotine policy, almost half of people who smoke (∼ 40%) do not support the policy. This study estimates the factors most strongly associated with support or opposition toward the policy, including tobacco use status, perceived effects of a reduced nicotine policy, trust in the FDA, and psychological distress. The study aims to inform messaging campaigns and policy makers. METHODS: Data were collected in 2021 with nationally representative samples of U.S. adults (n = 1763). After receiving information about the reduced nicotine policy, participants indicated their beliefs and support for or opposition to the policy, along with other individual difference characteristics. Univariate population parameters and multinomial logistic regression coefficients were estimated. RESULTS: In adjusted models, people who formerly or never smoked were less likely to oppose the policy compared to those who currently smoke; people with higher psychological distress and those who believe the policy will promote switching to e-cigarettes were more likely to oppose the policy. In addition, people were more likely to support the policy if they believed it would make quitting easier or that the FDA is trustworthy. CONCLUSIONS: Educational campaigns about reduced nicotine policy should expect higher impact by targeting prevalent perceptions and those more strongly associated with policy sentiment. In anticipation of the policy rollout, there may be a critical window to shape public opinion.

Reactions to Messages About a Nicotine Reduction Policy: A Focus Group Study Among People Who Use Little Cigars and Cigarillos.

INTRODUCTION: The U.S. Food and Drug Administration (FDA) has proposed rulemaking to reduce the nicotine content in cigarettes and other combusted tobacco products to non-addictive levels. This qualitative study documents reactions to messages communicating this policy among people who use little cigars and cigarillos (LCCs). AIMS AND METHODS: We conducted eight focus groups with participants from four populations with the highest prevalence of cigar use (African American males and females, white males and females). Participants described their reactions to eight messages about the policy: Three messages about the equal risk of LCCs with regular and low nicotine levels; three quit efficacy messages about low nicotine LCCs being easier to quit; one "compensation" message to correct misperceptions about the policy causing people to smoke more to get desired nicotine; and one message about using alternative nicotine sources (eg, e-cigarettes). RESULTS: Participants perceived risk messages as the most motivating to quit, whereas efficacy messages made some participants feel that the policy would cause former users of LCCs to relapse. Many participants expressed favorable responses to the compensation message. The message about using alternative nicotine sources sparked intense responses, with many participants expressing outrage and mistrust of the message. Participants' beliefs that they were not addicted to LCCs dampened their perceptions of the effectiveness of the policy. CONCLUSIONS: Perceptions of the addictiveness and relative harms of LCCS influenced responses to policy messages. The FDA should consider using different messages to communicate with people who use LCCs because they perceive LCCs as different from cigarettes. IMPLICATIONS: This is the first study to document affective and cognitive responses to the FDA's reduced nicotine policy among people who use LCCs. The false belief that cigar products are less harmful than cigarettes may be influencing people's lack of support for the reduced nicotine policy and difficulty in understanding its potential positive impact. To maximize the public health benefit of the reduced nicotine policy, the FDA should include LCC products in the policy; however, it is crucial that they use educational messaging to clarify misperceptions regarding nicotine and harm as it applies to LCCs.

Independent and combined effects of very low nicotine cigarette messages and e-cigarette messages: a randomised clinical trial.

BACKGROUND: USA is considering reducing nicotine in cigarettes to non-addictive levels, coupled with promoting alternative nicotine delivery products (eg, e-cigarettes). However, effective communication is needed to reduce misperceptions about very low nicotine cigarettes (VLNCs) being less harmful than regular cigarettes. METHODS: In 2022-2023, we conducted a four-group randomised clinical trial with a national probability sample from an online panel (971 adults who smoked cigarettes exclusively, 472 adults who dual used cigarettes and e-cigarettes and 458 adults aged 18-29 who had never smoked). Participants were randomised (parallel assignment) to one message condition: (1) VLNCs as harmful but easier to quit than regular cigarettes (n=468), (2) those who are not ready to quit should consider switching to e-cigarettes as less harmful alternatives (n=484), (3) combined (VLNC and e-cigarette messages; n=476) or (4) control condition (ie, water ads), n=473. The primary outcome was perceived absolute harm of VLNCs. RESULTS: Perceived harm of VLNCs was higher in the VLNC condition compared with the e-cigarette and control conditions, and higher in the combined condition compared with the e-cigarette condition (adjusted p<0.05). Among adults who dual used, intention to switch to e-cigarettes was higher in the VLNC condition than the e-cigarette, combined or control conditions (adjusted p<0.05). CONCLUSIONS: VLNC messages reduced the misperception that VLNCs are less harmful than cigarettes, but adding messages about e-cigarettes did not enhance desired outcomes. These VLNC messages can be considered during the rollout of a reduced nicotine policy. TRIAL REGISTRATION: NCT05506046.

Cross-platform immunophenotyping of human peripheral blood mononuclear cells with four high-dimensional flow cytometry panels.

Immunophenotyping using high dimensional flow cytometry is a central component of human immune system multi-omic studies. We present four high parameter flow cytometry panels for deep immunophenotyping of human peripheral blood mononuclear cells (PBMC). This set of four 25+ color panels include 64 cell surface markers to resolve broad immune compartment populations, as well as activation and memory of specific T, B, natural killer (NK), and myeloid lineages. Common lineage bridging markers are integrated into each panel to allow for inter-panel quality control through major lineage frequency verification. These panels were developed using a five laser BD Symphony A5 conventional cytometer and successfully transferred to a five laser Cytek Aurora spectral cytometer capable of acquiring the panels. Nine representative PBMC samples were stained with the four phenotyping panels and acquired on both instruments to evaluate population frequency and visual staining patterns for gating between the systems. Both instruments produced comparable high quality flow cytometry data and supported our decision to acquire samples on the spectral cytometer moving forward. This modular set of panels and instrument performance metrics provide guidelines for designing flow cytometry experiments suitable for longitudinal or cross-sectional immune profiling.

"I'm Bored and I'm Stressed": A Qualitative Study of Exclusive Smokers, ENDS Users, and Transitioning Smokers or ENDS Users in the Time of COVID-19.

BACKGROUND: To better understand the various influences of COVID-19 on tobacco use, we examined three different tobacco user groups using qualitative methods. METHODS: Ten online focus groups with 61 adults from the Atlanta, GA area were held in October-November 2020: four with exclusive smokers (n = 16), three with Electronic Nicotine Delivery System (ENDS) users (dual and exclusive, n = 22), and three with transitioning (recently quit or currently quitting) smokers and/or ENDS users (n = 23). RESULTS: Exclusive smokers reported smoking more frequently, driven by COVID-19-related stress, time at home, and boredom. They were not motivated to quit during the pandemic, and some considered smoking to be protective against COVID-19. ENDS users reported vaping less, with dual users often increasing their smoking; many were concerned about health effects of smoking and ENDS use during the pandemic. Transitioning smokers/ENDS users worried about their health and wanted to quit, but many found the stress of COVID-19 unbearable without tobacco use. CONCLUSIONS: There were some similarities among the groups, but also pronounced differences. Educational campaigns should capitalize on the teachable moment of COVID-19 to increase perceived risk of smoking. Smokers need access to more adaptive ways to deal with stress (such as mindfulness training) in lieu of smoking and systems-level approaches should address structural determinants of health that cause high levels of stress. The proposed policy to lower nicotine in combusted tobacco products might help smokers choose other means of coping instead of cigarettes by reducing the stress-relieving properties of smoking particularly salient during the pandemic. IMPLICATIONS: Smokers believe that cigarettes help them deal with the stresses and challenges of the COVID-19 pandemic. This needs to be counteracted by educational campaigns to increase perceived harm of smoking, alternative stress-relief strategies, and mandated changes to the combusted tobacco products to make them less appealing.

Brief report on IQOS point-of-sale marketing, promotion and pricing in IQOS retail partner stores in Atlanta, Georgia, USA.

OBJECTIVES: Philip Morris has a history of aggressive marketing tactics in its global pursuit of IQOS sales, which extant literature suggests may appeal to non-smokers and young adults. This study was the first to examine point-of-sale (POS) marketing and pricing of IQOS after it entered the US market in October 2019. METHODS: Trained field staff assessed 75 retail partner stores selling IQOS/HeatSticks in the Atlanta area in February-November 2020 using an IQOS-tailored, standardised assessment tool. The tool assessed store characteristics, product availability and accessibility, marketing and promotions and pricing for each store. RESULTS: All stores assessed sold HeatSticks in at least one of the three flavours (tobacco, smooth menthol, fresh menthol), but did not sell the IQOS device. IQOS/HeatSticks marketing was present inside 98.5% and outside 17.3% of stores assessed. Marketing for other tobacco products was present inside 98.5% and outside 32% of stores. The average price per HeatSticks pack was US$6.40 compared with US$6.08 for Marlboro Red cigarettes. CONCLUSION: Our study revealed a considerable amount of POS marketing and promotion for IQOS/HeatSticks at retail partner locations, visible to all retail consumers, including youth and non-smokers. This study was the first to examine IQOS POS marketing and promotion in the US context and findings add to the extant literature on IQOS global marketing strategies. As additional novel tobacco/nicotine products continue to enter the market, targeted monitoring of the POS marketing and promotion for these new products is warranted.

Increase in invasive group A streptococcal infection notifications, England, 2022.

Increases in invasive group A streptococcal (iGAS) infection and associated deaths, particularly in children, above seasonally expected levels are being seen this season (772 notifications reported in weeks 37 to 48 in 2022) across England. Diagnoses of iGAS infection from lower respiratory tract specimens in children under 15 years increased to 28% in November 2022. Medical practitioners have been alerted to the exceptional increase in incidence, including unusual numbers of children presenting with pulmonary empyema.

Caring for a child with an eating disorder: Understanding differences among mothers and fathers of adolescent and adult children.

OBJECTIVE: This study investigated treatment-engagement fears, self-efficacy, and accommodating and enabling in mothers and fathers of adolescent and adult children with eating disorders. METHODS: This study involved a secondary analysis of pre-treatment data from a subsample of 143 parents (95 mothers; 48 fathers) from a Canada-wide multi-site study. Parents completed the Caregiver Traps Scale, Parents Versus Anorexia Scale, and the Accommodation and Enabling Scale for Eating Disorders. Data were analysed using factorial Multivariate Analysis of Variance and mediation via multiple regression. RESULTS: Mothers reported higher levels of treatment-engagement fears than fathers. Among mothers, higher fear predicted lower self-efficacy and more accommodating and enabling behaviours. Among fathers, neither fear nor self-efficacy predicted accommodating and enabling. No differences in treatment-engagement fear or self-efficacy between parents of adolescent child and adult children were found at pre-treatment. CONCLUSIONS: Mothers' and fathers' experience different levels of fear related to their involvement in their ill-child's treatment at pre-treatment, and that fear is uniquely related to variables that impact treatment outcomes. There is a need to support parents even when their child is an adult. This study can inform family-based treatments vis-a-vis tailoring interventions for mothers and fathers and providing support to parents of children with eating disorders across the lifespan.

Perceptions of Nicotine Reduction Policy in the United States: A Qualitative Study.

INTRODUCTION: Several countries are considering a reduced nicotine policy that would make cigarettes minimally or nonaddictive. This qualitative study documents reactions to the policy that should be addressed by future communication efforts. METHODS: In 2020, we recruited participants in Atlanta, GA and San Francisco, CA (27 people who exclusively smoke, 25 who dual use cigarettes and e-cigarettes, 32 who formerly smoked, and 31 young adults who do not smoke). We held 16 focus groups: 2 focus groups for each smoking status in each city. Participants viewed messages about very low nicotine content cigarettes (VLNCs) and were asked about their reactions to each message and their overall response to the reduced nicotine policy. RESULTS: While responses to the policy were predominantly positive, focus group discussion also revealed concerns, questions, and misunderstandings (referred to here collectively as "perceptions") that may need to be addressed if a reduced nicotine policy is enacted. Participants expressed perceptions related to the policy intent, including that the FDA has ulterior motives, adoption/ implementation, including that nicotine would have to be replaced with other chemicals if removed or that the policy would be unfeasible to implement, and effectiveness, including concern that VLNCs would still be addictive or the policy would backfire. CONCLUSIONS: Addressing perceptions about reduced nicotine policy intent, adoption/implementation, and effectiveness could be key in creating public support and political motivation to move forward with such a policy. Countries contemplating adopting such a policy should consider pairing it with communications that address these perceptions. IMPLICATIONS: This study is one of very few to use qualitative methods to explore potentially problematic perceptions about nicotine reduction policy among US adults. Results illuminated new policy-specific concerns, questions, and misunderstandings about the reduced nicotine policy intent, adoption/implementation, and effectiveness. Identifying, studying, and addressing relevant perceptions may play a key role in generating support in countries contemplating such a policy.

'It brings light to what you really put into your body': a focus group study of reactions to messages about nicotine reduction in cigarettes.

OBJECTIVE: In 2017, the US Food and Drug Administration (FDA) announced a proposed regulation to lower nicotine in cigarettes to minimally addictive levels to help smokers quit. We sought to explore effective message strategies communicating about nicotine reduction in cigarettes across the different key audiences that the regulation is most likely to influence. METHODS: We designed four types of messages: efficacy messages, risk messages, a message about alternative sources of nicotine and a compensation message. Sixteen virtual focus groups were conducted in Atlanta and San Francisco in April-May 2020. Data were analysed in NVivo 12.0 using a thematic analysis approach. FINDINGS: Exclusive smokers were receptive to both efficacy messages and risk messages. Dual users were the only group that was open to resorting to alternative sources of nicotine. Former smokers were critical of these messages as promoting the new kinds of cigarettes and potentially encouraging initiation and relapse of smoking. Non-smokers felt that efficacy messages downplayed the risks of smoking and did not scare people away from smoking. Presenting information that very low nicotine cigarettes (VLNCs) still contain harmful chemicals made smokers question continued smoking in the absence of nicotine and view VLNCs as harmful. CONCLUSIONS: Messages communicating about nicotine reduction in cigarettes might help to motivate smokers to quit and can correct the misperceptions that VLNCs are less harmful. The FDA should consider specific target audiences and use different messages that complement each other in communicating about this regulation.

Messaging about very low nicotine cigarettes (VLNCs) to influence policy attitudes, harm perceptions and smoking motivations: a discrete choice experiment.

BACKGROUND: To reduce smoking and the harms it causes, countries, including the USA, are considering policies to reduce nicotine in combustible tobacco to minimally addictive levels. Effective messages about very low nicotine cigarettes (VLNCs) and this policy are crucial in combating misperceptions threatening the policy's effectiveness. DATA AND METHODS: A discrete choice experiment assessed messages about VLNCs. Participants were 590 adults who smoked exclusively, 379 adults who both smoked and used e-cigarettes, 443 adults who formerly smoked and 351 young adults who never smoked (total n=1763). Seven message attributes were varied systematically (source, harm, chemicals, nicotine, satisfaction, addictiveness and quitting efficacy). Outcomes were selection of messages that generated the most positive attitude towards reduced nicotine policy, the greatest perceived harmfulness of VLNCs, and most strongly motivated quitting and initiating behaviour for VLNCs. RESULTS: Information about specific harms and chemicals of VLNCs had the largest effects on selection of messages as eliciting more negative attitudes towards VLNCs policy, increasing perceived VLNC harmfulness, increasing motivation to quit VLNCs and decreasing motivation to try VLNCs. Messages with information about quitting efficacy were selected as more motivating to quit among those who smoke, but also more motivating to try VLNCs among those who do not smoke. CONCLUSION: Harm and chemical information can be prioritised to ensure VLNCs are not misperceived as less harmful than regular cigarettes. Messages about increased quitting efficacy and reduced addictiveness associated with VLNCs may backfire if presented to those who do not smoke.

A Content Analysis of U.S. Adults' Open-Ended Responses to E-Cigarette Risk Messages.

To better understand the processing of e-cigarette prevention messages, we conducted a content analysis of 1,968 participants' open-ended responses to one of four messages, which focused on industry manipulation (Big tobacco), financial and psychological cost of vaping (Can't afford), harmful chemicals in e-cigarettes (Formaldehyde), or uncertainty about the ingredients of e-liquids (Top secret). Health Belief Model (HBM) and perceived message effectiveness (PME) constructs were coded and the frequency of each variable was compared across message conditions. Among the HBM constructs, perceived health threat had the most mentions overall (38.8%). Self-efficacy of staying away from vaping had the fewest mentions across all messages (0.56%). For PME, participants more frequently mentioned message perceptions (15.75% positive message perceptions, 8.38% negative) than effect perceptions (3.46% positive effect perceptions, 1.37% negative). Big tobacco received the highest number of mentions for positive message perceptions and Formaldehyde received the highest number of mentions for positive effect perceptions. Future anti-vaping messages are recommended to address the efficacy element and to combine different themes to communicate harms of e-cigarettes.

'The lesser devil you don't know': a qualitative study of smokers' responses to messages communicating comparative risk of electronic and combusted cigarettes.

INTRODUCTION: Communicating to smokers that e-cigarettes deliver lower levels of harmful chemicals than combusted cigarettes is a challenging issue. This study qualitatively explored smokers' interpretations of messages communicating the risk of e-cigarettes relative to cigarettes (comparative risk messages). METHOD: We developed 12 print comparative risk messages and evaluated them in 12 focus groups with 72 adult smokers (18+ years old) in Atlanta, Georgia. RESULTS: Participants interpreted uncertainty about health effects of e-cigarettes as an indicator of significant unknown risks, which some believed to be potentially more severe than the known effects of cigarettes (such as cancer and heart disease). Also, participants were sceptical about the lower risk claims. Some participants misinterpreted what 'switching completely' or 'switching 100% of the time' means, perceiving switching from e-cigarettes to combusted cigarettes as comparable with the use of both products. When chemicals in e-cigarettes were mentioned (eg, nicotine or formaldehyde), participants viewed e-cigarettes as very harmful and had difficulty reconciling this belief with the reduced risk claim. Comparative risk messages emphasising smoking risks were perceived as effective. Participants also appreciated being given an option to switch if they cannot quit. Participants suggested the inclusion of more facts and statistics and a credible message source (eg, public health agencies) to increase message effectiveness. CONCLUSION: Comparative risk messages may be more acceptable to smokers if they show direct comparisons of the number of toxic chemicals in cigarettes and e-cigarettes, are attributed to a credible source(s), and emphasise smoking risks.

Modifications to Electronic Nicotine Delivery Systems: Content Analysis of YouTube Videos.

BACKGROUND: As user modification can alter the addictiveness and toxicity of electronic nicotine delivery systems (ENDS), more research is needed to understand the types, motivations, risks, and information sources that lead to these product alterations. YouTube has been identified as a major platform where ENDS users obtain and share information about ENDS products and modifications. However, a comprehensive study of ENDS modification videos on YouTube is lacking. OBJECTIVE: This study aimed to analyze the content of YouTube videos depicting modifications of ENDS. METHODS: YouTube was searched in March 2019 to identify videos depicting ENDS modifications. Search terms were derived from interviews with ENDS users and current literature. We used 28 search phrases that combined the words vape and vaping with modification-related key terms (eg, custom build, modification, and dripping). The final sample included 168 videos. RESULTS: Videos were 1 to 108 min long (median 9.55). Presenters were largely male (117/168, 69.6%), white (94/168, 56.0%), and older than 25 years (94/168, 56.0%). Most videos gave how to instructions (148/168, 88.1%), but few offered warnings (30/168, 17.9%) or mentioned commercial alternatives to modifications they presented (16/168, 9.5%). The ENDS devices most often featured were drippers (63/168, 37.5%) and refillable tanks (37/168, 22.0%). The most often modified ENDS components were coils (82/168, 48.8%) and e-liquids (34/168, 20.2%), which included adding other substances, such as cannabis, to the e-liquids (6/168, 3.6%). Most videos portrayed ENDS modifications positively (106/168, 63.1% positive; 60/168, 35.7% neutral; and 2/168, 1.2% negative) and were either neutral or positive in their overall portrayal of ENDS devices (78/168, 46.4% positive; 89/168, 53.0% neutral; and 1/168, 0.6% negative). CONCLUSIONS: This study identified several concerning trends in popular YouTube videos on ENDS modifications, including lack of warnings, the addition of marijuana derivatives to e-liquids, and the positive portrayal of ENDS devices and modifications. By identifying the types of modifications (coil and e-liquid being the most prevalent), this study sets an agenda for research on the effects of modifications.

Bingeing, Purging, and Suicidal Ideation in Clinical and Non-Clinical Samples of Youth.

Suicidal ideation is a serious mental health concern reported by adolescents. Despite understanding of increased suicidal ideation in patients with eating disorders (EDs) and obesity, few studies have compared how disordered eating (bingeing, vomiting and over exercising) is associated with suicidal ideation in clinical and non-clinical samples of youth across the ED and weight spectrum. The present study aimed to 1) comparatively examine rates of suicidal ideation and disordered eating behaviors in clinical samples of youth with EDs, complex obesity, or from the community, and 2) examine whether disordered eating was associated with suicidal ideation above and beyond age, body mass index, diagnosis, treatment-seeking status, and depressive symptoms in large samples of males vs. females in an attempt to understand whether these behaviors should lead to concern regarding suicidal ideation. Data from charts on treatment-seeking adolescents diagnosed with either an ED (N = 315), severe complex obesity (N = 212), and from the community (N = 3036) were pooled together for comparative purposes. Results showed that suicidal ideation was higher in youth seeking treatment for an ED (50.2%) and obesity (23.7%) as compared to youth from the community (13%). Binary logistic regression analyses revealed that vomiting (OR = 1.73 for females, 8.17 for males) and over-exercising (OR = 1.47 for females, 1.68 for males) was significantly associated with suicidal ideation in both males and females. Findings underscore the importance of screening for suicidal ideation in youth who report vomiting or over-exercising despite diagnostic presentation, age, weight, or treatment setting.

Development of the Ottawa Disordered Eating Screen for Youth: The ODES-Y.

OBJECTIVE: To develop a concise screening tool that allows for early identification of disordered eating in youth. STUDY DESIGN: In this 2-step classification accuracy study, questions for the Ottawa Disordered Eating Screen-Youth, a 2-question screening tool (index test), were conceptualized by clinician-scientists from tertiary care pediatric eating disorder and weight-related clinics, and was validated using retrospective data (2004-2010) from a community-based study, the Research on Eating and Adolescent Lifestyles (REAL) study. RESULTS: Analyses of contrast between the index test and the reference standard using data from 2892 (1714 females) students between grade 7 and grade 12 revealed classification statistics of 67.1% for sensitivity, 85.9% for specificity, 4.7 for positive likelihood ratio, 0.38 for negative likelihood ratio, 50.6% for positive predictive value, and 92.4% for negative predictive value for females and 61.1% for sensitivity, 93.9% for specificity, and 9.9 for positive likelihood ratio, 0.41 for negative likelihood ratio, 32.3% for positive predictive value, and 98.0% for negative predictive value for males. CONCLUSIONS: Our findings suggest that the index test has utility as a short and accurate screening tool for earlier detection of disordered eating thoughts and behaviors in youth. Additional research is needed to best determine how the index test can be administered to youth across various health care, school, public health, and surveillance settings in clinically sensitive pragmatic ways.

Association between use of different antibiotics and trimethoprim resistance: going beyond the obvious crude association.

Objectives: To evaluate the association between use of different antibiotics and trimethoprim resistance at the population level. Methods: Monthly primary care prescribing data were obtained from NHS Digital. Positive Enterobacteriaceae records from urine samples from patients between April 2014 and January 2016 in England were extracted from PHE's Second Generation Surveillance System (SGSS). Elastic net regularization and generalized boosted regression models were used to evaluate associations between antibiotic prescribing and trimethoprim resistance, both measured at Clinical Commission Group level. Results: In total, 2 487 635 (99%) of 2 513 285 urine Enterobacteriaceae samples from 1 667 839 patients were tested for trimethoprim resistance. Using both elastic net regularization and generalized boosted regression models, geographical variation in trimethoprim resistance among Enterobacteriaceae urinary samples could be partly explained by geographical variation in use of trimethoprim (relative risk = 1.14, 95% CI = 1.02-1.75; relative influence = 4.1) and penicillins with extended spectrum (mainly amoxicillin/ampicillin in England) (relative risk = 1.19, 95% CI = 1.11-1.30; relative influence = 7.4). Nitrofurantoin use was associated with lower trimethoprim resistance levels (relative risk = 0.83, 95% CI = 0.57-0.96; relative influence = 9.2). Conclusions: Use of amoxicillin/ampicillin explained more of the variance in trimethoprim resistance than trimethoprim use, suggesting that co-selection by these antibiotics is an important driver of trimethoprim resistance levels at the population level. Nitrofurantoin use was consistently associated with lower trimethoprim resistance levels, indicating that trimethoprim resistance levels could be lowered if trimethoprim use is replaced by nitrofurantoin.