Paul Aveyard

University of Oxford | OX · Department of Primary Care Health Sciences

The gut microbiome may be a mediator between obesity and health outcomes. However, it is unclear how intentional weight loss changes the gut microbiota and intestinal permeability. We aimed to systematically review and quantify this association. We searched Medline, Embase, CINAHL, Cochrane databases, and trial registries until June 2020 (PROSPERO:...

Objective: The aim of this study was to develop a shortened Oxford Food and Activity Behaviors (OxFAB) questionnaire to identify the cognitive and behavioral strategies used by individuals during weight-management attempts. Methods: This study reduced an existing 117-item questionnaire (the original OxFAB questionnaire) through identifying clust...

Objective: Behavioral weight management programs (BWMPs) for adults lead to greater weight loss at 12 months than minimal-intervention control treatments. However, there is considerable heterogeneity in the content of BWMPs and outcomes of treatment. This study assessed the contribution of individual components of BWMPs, using Bayesian component n...

Nonalcoholic steatohepatitis (NASH) is a prevalent chronic disease that is associated with a spectrum of liver fibrosis and can lead to cirrhosis. Patients with NASH report lower health-related quality of life (HRQoL) than the general population. It remains uncertain how changes in histologic severity are associated with changes in HRQoL. This is a...

Objectives To identify and prioritise the most impactful, unanswered questions for obesity and weight-related research. Design Prioritisation exercise of research questions using online surveys and an independently facilitated workshop. Setting Online/virtual. Participants We involved members of the public including people living with obesity, r...

Background: A high BMI has been associated with a reduced immune response to vaccination against influenza. We aimed to investigate the association between BMI and COVID-19 vaccine uptake, vaccine effectiveness, and risk of severe COVID-19 outcomes after vaccination by using a large, representative population-based cohort from England. Methods:...

Background: The aim was to assess whether an intervention incorporating a practicable open-label n-of-1 trial would lead to greater uptake of statin than usual care and comparable uptake to a closed-label gold-standard n-of-1 trial. Methods: We enrolled patients who had stopped or declined statins into a 3-arm trial (usual care, unblinded, and b...

Background Higher body mass index (BMI) and metabolic consequences of excess weight are associated with increased risk of severe COVID-19, though their mediating pathway is unclear. Methods A prospective cohort study included 435,504 UK Biobank participants. A two-sample Mendelian randomisation (MR) study used the COVID-19 Host Genetics Initiative...

Background: Motivational interviewing (MI) is potentially useful in management of overweight and obesity, but staff training and increased delivery time are barriers, and its effectiveness independent of other behavioral components is unclear. Purpose: To assess the independent contribution of MI as part of a behavioral weight management program...

OBJECTIVE To identify dietary patterns (DPs) characterized by a set of nutrients of concern and their association with incident type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS A total of 120,343 participants from the U.K. Biobank study with at least two 24 h dietary assessments were studied. Reduced rank regression was used to derive DPs explai...

Background: Smoking is a risk factor for most respiratory infections, but it may protect against SARS-CoV-2 infection. The objective was to assess whether smoking and e-cigarette use were associated with severe COVID-19. Methods: This cohort ran from 24 January 2020 until 30 April 2020 at the height of the first wave of the SARS-CoV-2 epidemic i...

Background: Guidelines recommend that GPs give patients lifestyle advice to manage hypertension and diabetes. Increasing evidence shows that this is an effective and practical treatment for these conditions, but it is unclear whether GPs offer this support. Aim: To investigate trends in the percentage of patients with hypertension/diabetes recei...

Background Contested evidence suggests that obesity confers no risk to health in people who have a healthy lifestyle, particularly if there are no metabolic complications of obesity. The aim was to examine the association between adherence to lifestyle recommendations and the absence of metabolic complications on the incident or fatal cardiovascula...

Objectives: The aim was to investigate the impact of a group-based weight management programme on symptoms of depression and anxiety compared with self-help in a randomised controlled trial (RCT). Method: People with overweight (Body Mass Index [BMI]≥28kg/m2) were randomly allocated self-help (n = 211) or a group-based weight management programm...

Background: Rapid weight gain is common with antipsychotic medication. Lost confidence, low mood and medication non-adherence often follow. Yet, the dynamic interactions between the physical and psychological consequences of weight gain, and implications for intervention, are unknown. Objectives: We examined first-person accounts of weight gain...

Aims To investigate the comparative and combined effectiveness of four types of components of behavioural interventions for cigarette smoking cessation: behavioural (e.g. counselling), motivational (e.g. focus on reasons to quit), delivery mode (e.g. phone), and provider (e.g. nurse). Design Systematic review and component network meta-analysis of...

Background Reducing meat consumption could protect the environment and human health. Objectives We tested the impact of a behavioral intervention to reduce meat consumption. Design Adult volunteers who regularly consumed meat, were recruited from the general public and randomized 1:1 to an intervention or control condition. The intervention compr...

Aims To summarise evidence on tobacco addiction interventions published by the Cochrane Tobacco Addiction Group (CTAG) from 2019 to 2020. Methods Narrative summary of all new and updated Cochrane Reviews published by CTAG in 2019 and 2020, outlining key results and promising avenues for future research. Results CTAG published six new reviews and...

Background and Aims Clinicians could promote e-cigarettes for harm reduction to people who smoke but cannot stop, but many clinicians feel uneasy doing so. In a randomised controlled trial (RCT), primary care clinicians offered free e-cigarettes and encouraged people with chronic diseases who were unwilling to stop smoking to switch to vaping. We i...

Background In the UK, about 14% of community-dwelling adults aged 65 and over are estimated to be at risk of malnutrition. Screening older adults in primary care and treating those at risk may help to reduce malnutrition risk, reduce the resulting need for healthcare use and improve quality of life. Interventions are needed to raise older adults’ r...

Introduction: People with serious mental illness (SMI), which includes people with diagnoses of schizophrenia spectrum and bipolar disorders, face significant health inequality. This includes a life expectancy reduced by 15-20 years mostly due to premature cardiovascular disease (CVD) compared with the general population. Excess weight gain and re...

To test the long-term effectiveness of a total diet replacement programme (TDR) for routine treatment of obesity in a primary care setting. This study was a pragmatic, two-arm, parallel-group, open-label, individually randomised controlled trial in adults with obesity. The outcomes were change in weight and biomarkers of diabetes and cardiovascular...

Behavioural weight management interventions are recommended for the treatment of obesity in children. However, the evidence for these is limited and often generated under trial conditions with White, middle-class populations. Healthy Eagles is a behavioural weight management intervention designed to treat excess weight in children. It ran in the Lo...

Background A high-salt diet is a risk factor for hypertension and cardiovascular disease; therefore, reducing dietary salt intake is a key part of prevention strategies. There are few effective salt reduction interventions suitable for delivery in the primary care setting, where the majority of the management and diagnosis of hypertension occurs....

Background: Most people who stop smoking gain weight. This can discourage some people from making a quit attempt and risks offsetting some, but not all, of the health advantages of quitting. Interventions to prevent weight gain could improve health outcomes, but there is a concern that they may undermine quitting. Objectives: To systematically r...

Objectives To determine the most cost-effective weight management programmes (WMPs) for adults, in England with severe obesity (BMI ≥ 35 kg/m ² ), who are more at risk of obesity related diseases. Methods An economic evaluation of five different WMPs: 1) low intensity (WMP1); 2) very low calorie diets (VLCD) added to WMP1; 3) moderate intensity (W...

People with serious mental illness (SMI) have identified barriers to engaging in behavioral weight management interventions (BWMIs). We assessed whether BWMIs that addressed these barriers were more effective. First, we systematically reviewed qualitative literature and used a thematic analysis to identify the characteristics of BWMIs that promote...

Background Conflicting evidence has emerged regarding the relevance of smoking on risk of COVID-19 and its severity. Methods We undertook large-scale observational and Mendelian randomisation (MR) analyses using UK Biobank. Most recent smoking status was determined from primary care records (70.8%) and UK Biobank questionnaire data (29.2%). COVID-...

Background Unexpected weight loss (UWL) is a presenting feature of cancer in primary care. Existing research proposes simple combinations of clinical features (risk factors, symptoms, signs, and blood test data) that, when present, warrant cancer investigation. More complex combinations may modify cancer risk to sufficiently rule-out the need for i...

Objective To determine if the characteristics of behavioural weight loss programmes influence the rate of change in weight after the end of the programme. Design Systematic review and meta-analysis. Data sources Trial registries, 11 electronic databases, and forward citation searching (from database inception; latest search December 2019). Random...

The relationship between BMI and health-related quality of life (HRQoL) critically affects regulatory approval of interventions for weight loss, but evidence of the association is inconsistent. A higher standard of evidence than that available was sought with an IPD meta-analysis of 10,884 people enrolled in five randomized controlled trials of int...

Introduction Nicotine replacement therapy (NRT) is effective for smoking cessation, but the optimal method of using NRT to maximize benefit is unclear. We examined whether nicotine dependence was associated with consumption of NRT, whether this was mediated by withdrawal symptoms, and the impact of these factors on cessation, in a population advise...

Objective Guidelines recommend that clinicians should offer patients with obesity referrals to weight management services. However, clinicians and patients worry that such conversations will generate friction, and the risk of this is greatest when patients say no. We examined how doctors actually respond to patient refusals, and how patients reacte...

Objective: To assess GPs' thoughts, feelings, and practices on providing opportunistic weight loss interventions before and after educational training and application in practice. Methods: In an embedded sequential mixed-methods design, 137 GPs delivered a 30-second brief opportunistic intervention to a mean of 14 patients with obesity. To asses...

Background Traditionally, studies investigating diet and health associations have focused on single nutrients. However, key nutrients co-exist in many common foods, and studies focusing solely on individual nutrients may obscure their combined effects on cardiovascular disease (CVD) and all-cause mortality. We aimed to identify food-based dietary p...

Background and aim Trials of treatments for non-alcoholic steatohepatitis require endpoint assessment with liver biopsies. Previous large-scale trials have calculated their sample size expecting high retention but on average did not achieve this. We aimed to quantify the proportion of participants with a valid follow-up biopsy. Methods We conducte...

Background and aims Weight loss is recommended for patients with non-alcoholic steatohepatitis (NASH) but the impact of weight change on disease activity remains unclear. We examined the association between weight change (gain/loss) and changes in biochemical and histological features of NASH. Methods This was an analysis of the PIVENS and FLINT t...

Background Previous studies suggested that the prevalence of chronic respiratory disease in patients hospitalised with COVID-19 was lower than its prevalence in the general population. The aim of this study was to assess whether chronic lung disease or use of inhaled corticosteroids (ICS) affects the risk of contracting severe COVID-19. Methods In...

Background Obesity is a major risk factor for adverse outcomes after infection with SARS-CoV-2. We aimed to examine this association, including interactions with demographic and behavioural characteristics, type 2 diabetes, and other health conditions. Methods In this prospective, community-based, cohort study, we used de-identified patient-level...

Background: The 'Primary Care SHOPping Intervention for Cardiovascular Disease Prevention' (PCSHOP) trial tested the effectiveness and feasibility of a behavioural intervention to reduce saturated fat in food purchases. The intervention offered feedback from data collected through a supermarket loyalty card to supplement brief advice from a nurse....

Background: There is a common perception that smoking generally helps people to manage stress, and may be a form of 'self-medication' in people with mental health conditions. However, there are biologically plausible reasons why smoking may worsen mental health through neuroadaptations arising from chronic smoking, leading to frequent nicotine wit...

Background Combinations of inflammatory markers are used as prognostic scores in cancer patients with cachexia. We investigated whether they could also be used to prioritise patients attending primary care with unexpected weight loss for cancer investigation. Methods We used English primary care electronic health records data linked to cancer regi...

Background: Smoking is a leading cause of disease and death worldwide. In people who smoke, quitting smoking can reverse much of the damage. Many people use behavioural interventions to help them quit smoking; these interventions can vary substantially in their content and effectiveness. Objectives: To summarise the evidence from Cochrane Review...

Background Tobacco smoking rates are significantly higher in people with common mental illness compared to those without. Smoking cessation treatment could be offered as part of usual outpatient psychological care, but currently is not. Objective To understand patient and health care professionals' views about integrating smoking cessation treatme...

Background GPs are encouraged to make brief interventions to support weight loss, but they report concern about these conversations, stating that they need more details on what to say. Knowing how engage in these conversations could encourage GPs to deliver brief interventions for weight loss more frequently. Objective To examine which specific wo...

Guidelines and evidence suggest primary care clinicians should give opportunistic interventions to motivate weight loss, but these rarely occur in practice. We sought to examine why by systematically reviewing qualitative research examining general practitioners' (‘GPs’) and nurses' views of discussing weight with patients. We systematically search...

Background Guidelines recommend that clinicians identify individuals at high cardiometabolic risk and support weight loss in those with overweight or obesity. However, we lack individual level data quantifying the benefits of weight change for individuals to guide consultations in primary care. Aim To examine how weight change affects cardiometabo...

BACKGROUND A high-salt diet is a risk factor for hypertension and cardiovascular disease; therefore, reducing dietary salt intake is a key part of prevention strategies. There are few effective salt reduction interventions suitable for delivery in the primary care setting, where the majority of the management and diagnosis of hypertension occurs....

Introduction: Smoking reduction can lead to increased success in quitting. This study aims to determine if a client-focused motivational support package for smoking reduction (and quitting) and increasing (or otherwise using) physical activity (PA) can help smokers who do not wish to quit immediately to reduce the amount they smoke, and ultimately...

Background Trials show that weight loss interventions improve biomarkers of non-alcoholic fatty liver disease (NAFLD), but it is unclear if a dose-response relationship exists. Objective We aimed to quantify the dose-response relationship between the magnitude of weight loss and improvements in NAFLD. Methods Nine databases and trial registries w...

Objectives To explore UK clinicians’ beliefs and behaviours around recommending e-cigarettes as a smoking cessation aid for patients with cancer. Design Cross-sectional online survey. Setting England, Wales, Scotland and Northern Ireland. Participants Clinicians involved in the care of patients with cancer. Primary and secondary outcomes Behavi...

Background Guidelines recommend reducing saturated fat (SFA) intake to decrease cardiovascular disease (CVD) risk, but there is limited evidence on scalable and effective approaches to change dietary intake, given the large proportion of the population exceeding SFA recommendations. We aimed to develop a system to provide monthly personalized feedb...

Weight loss programmes appeal mainly to women, prompting calls for gender-specific programmes. In the United Kingdom, general practitioners (GPs) refer nine times as many women as men to community weight loss programmes. GPs endorsement and offering programmes systematically could reduce this imbalance. In this trial, consecutively attending patien...

Background Short-term laboratory studies suggest that eating attentively can reduce food intake. However, in a recent randomized controlled trial we found no evidence that using an attentive eating smartphone app outside of the laboratory had an effect on energy intake or weight loss over 8 weeks. Objective This research examined trial participant...

Smoking rates in people with depression and anxiety are twice as high as in the general population, even though people with depression and anxiety are motivated to stop smoking. Most healthcare professionals are aware that stopping smoking is one of the greatest changes that people can make to improve their health. However, smoking cessation can be...

Background: There is considerable heterogeneity in long-term weight loss among people referred to obesity treatment programmes. It is unclear whether attendance at face-to-face sessions in the early weeks of the programme is an independent predictor of long-term success. Objective: To investigate whether frequency of attendance at a community we...

Objective To quantify the predictive value of unexpected weight loss (WL) for cancer according to patient’s age, sex, smoking status, and concurrent clinical features (symptoms, signs, and abnormal blood test results). Design Diagnostic accuracy study. Setting Clinical Practice Research Datalink electronic health records data linked to the Nation...

Background There is uncertainty about the associations of angiotensive enzyme (ACE) inhibitor and angiotensin receptor blocker (ARB) drugs with COVID-19 disease. We studied whether patients prescribed these drugs had altered risks of contracting severe COVID-19 disease and receiving associated intensive care unit (ICU) admission. Methods This was...

Background Evidence shows that clinician-delivered brief opportunistic interventions are effective in obesity, and guidelines promote their use. However, there is no evidence on how clinicians should do this, and guidelines are not based on clinical evidence. Purpose A trial (Brief Interventions for Weight Loss [BWeL]) showed that brief opportunis...