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1.
Lancet ; 403(10429): 838-849, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38364839

ABSTRACT

BACKGROUND: Individuals with serum antibodies to citrullinated protein antigens (ACPA), rheumatoid factor, and symptoms, such as inflammatory joint pain, are at high risk of developing rheumatoid arthritis. In the arthritis prevention in the pre-clinical phase of rheumatoid arthritis with abatacept (APIPPRA) trial, we aimed to evaluate the feasibility, efficacy, and acceptability of treating high risk individuals with the T-cell co-stimulation modulator abatacept. METHODS: The APIPPRA study was a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial done in 28 hospital-based early arthritis clinics in the UK and three in the Netherlands. Participants (aged ≥18 years) at risk of rheumatoid arthritis positive for ACPA and rheumatoid factor with inflammatory joint pain were recruited. Exclusion criteria included previous episodes of clinical synovitis and previous use of corticosteroids or disease-modifying antirheumatic drugs. Participants were randomly assigned (1:1) using a computer-generated permuted block randomisation (block sizes of 2 and 4) stratified by sex, smoking, and country, to 125 mg abatacept subcutaneous injections weekly or placebo for 12 months, and then followed up for 12 months. Masking was achieved by providing four kits (identical in appearance and packaging) with pre-filled syringes with coded labels of abatacept or placebo every 3 months. The primary endpoint was the time to development of clinical synovitis in three or more joints or rheumatoid arthritis according to American College of Rheumatology and European Alliance of Associations for Rheumatology 2010 criteria, whichever was met first. Synovitis was confirmed by ultrasonography. Follow-up was completed on Jan 13, 2021. All participants meeting the intention-to-treat principle were included in the analysis. This trial was registered with EudraCT (2013-003413-18). FINDINGS: Between Dec 22, 2014, and Jan 14, 2019, 280 individuals were evaluated for eligibility and, of 213 participants, 110 were randomly assigned to abatacept and 103 to placebo. During the treatment period, seven (6%) of 110 participants in the abatacept group and 30 (29%) of 103 participants in the placebo group met the primary endpoint. At 24 months, 27 (25%) of 110 participants in the abatacept group had progressed to rheumatoid arthritis, compared with 38 (37%) of 103 in the placebo group. The estimated proportion of participants remaining arthritis-free at 12 months was 92·8% (SE 2·6) in the abatacept group and 69·2% (4·7) in the placebo group. Kaplan-Meier arthritis-free survival plots over 24 months favoured abatacept (log-rank test p=0·044). The difference in restricted mean survival time between groups was 53 days (95% CI 28-78; p<0·0001) at 12 months and 99 days (95% CI 38-161; p=0·0016) at 24 months in favour of abatacept. During treatment, abatacept was associated with improvements in pain scores, functional wellbeing, and quality-of-life measurements, as well as low scores of subclinical synovitis by ultrasonography, compared with placebo. However, the effects were not sustained at 24 months. Seven serious adverse events occurred in the abatacept group and 11 in the placebo group, including one death in each group deemed unrelated to treatment. INTERPRETATION: Therapeutic intervention during the at-risk phase of rheumatoid arthritis is feasible, with acceptable safety profiles. T-cell co-stimulation modulation with abatacept for 12 months reduces progression to rheumatoid arthritis, with evidence of sustained efficacy beyond the treatment period, and with no new safety signals. FUNDING: Bristol Myers Squibb.


Subject(s)
Arthritis, Rheumatoid , Synovitis , Adolescent , Adult , Humans , Abatacept/adverse effects , Arthralgia , Arthritis, Rheumatoid/drug therapy , Pain , Rheumatoid Factor
2.
Thorax ; 79(6): 515-523, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38471792

ABSTRACT

RATIONALE: Heterogeneity of the host response within sepsis, acute respiratory distress syndrome (ARDS) and more widely critical illness, limits discovery and targeting of immunomodulatory therapies. Clustering approaches using clinical and circulating biomarkers have defined hyper-inflammatory and hypo-inflammatory subphenotypes in ARDS associated with differential treatment response. It is unknown if similar subphenotypes exist in sepsis populations where leucocyte transcriptomic-defined subphenotypes have been reported. OBJECTIVES: We investigated whether inflammatory clusters based on cytokine protein abundance were seen in sepsis, and the relationships with previously described transcriptomic subphenotypes. METHODS: Hierarchical cluster and latent class analysis were applied to an observational study (UK Genomic Advances in Sepsis (GAinS)) (n=124 patients) and two clinical trial datasets (VANISH, n=155 and LeoPARDS, n=484) in which the plasma protein abundance of 65, 21, 11 circulating cytokines, cytokine receptors and regulators were quantified. Clinical features, outcomes, response to trial treatments and assignment to transcriptomic subphenotypes were compared between inflammatory clusters. MEASUREMENTS AND MAIN RESULTS: We identified two (UK GAinS, VANISH) or three (LeoPARDS) inflammatory clusters. A group with high levels of pro-inflammatory and anti-inflammatory cytokines was seen that was associated with worse organ dysfunction and survival. No interaction between inflammatory clusters and trial treatment response was found. We found variable overlap of inflammatory clusters and leucocyte transcriptomic subphenotypes. CONCLUSIONS: These findings demonstrate that differences in response at the level of cytokine biology show clustering related to severity, but not treatment response, and may provide complementary information to transcriptomic sepsis subphenotypes. TRIAL REGISTRATION NUMBER: ISRCTN20769191, ISRCTN12776039.


Subject(s)
Cytokines , Phenotype , Sepsis , Transcriptome , Humans , Sepsis/blood , Sepsis/genetics , Male , Cytokines/blood , Female , Middle Aged , Leukocytes/metabolism , Biomarkers/blood , Aged , Cluster Analysis , Respiratory Distress Syndrome/blood , Respiratory Distress Syndrome/genetics , Respiratory Distress Syndrome/drug therapy , Treatment Outcome
3.
Diabet Med ; 40(10): e15165, 2023 10.
Article in English | MEDLINE | ID: mdl-37307016

ABSTRACT

AIMS: To estimate the prevalence of undiagnosed diabetes and suboptimally controlled diabetes and the associated risk factors by community screening in India. METHODS: In this multi-centre, cross-sectional study, house-to-house screening was conducted in people aged ≥40 years in urban and rural areas across 10 states and one union territory in India between November 2018 and March 2020. Participants underwent anthropometry, clinical and biochemical assessments. Capillary random blood glucose and point-of-care glycated haemoglobin (HbA1c ) were used to diagnose diabetes. The prevalence of undiagnosed diabetes and suboptimal control (HbA1c ≥53 mmol/mol [≥7%]) among those with known diabetes was assessed. RESULTS: Among the 42,146 participants screened (22,150 urban, 19,996 rural), 5689 had known diabetes. The age-standardised prevalence of known diabetes was 13.1% (95% CI 12.8-13.4); 17.2% in urban areas and 9.4% in rural areas. The age-standardised prevalence of undiagnosed diabetes was 6.0% (95% CI 5.7-6.2); similar in both urban and rural areas with the highest proportions seen in the East (8.0%) and South (7.8%) regions. When we consider all people with diabetes in the population, 22.8% of individuals in urban areas and 36.7% in rural areas had undiagnosed diabetes. Almost 75% of the individuals with known diabetes had suboptimal glycaemic control. CONCLUSIONS: High prevalence of undiagnosed diabetes and suboptimally controlled diabetes emphasises the urgent need to identify and optimally treat people with diabetes to reduce the burden of diabetes.


Subject(s)
Diabetes Mellitus , Humans , Cross-Sectional Studies , Diabetes Mellitus/diagnosis , Diabetes Mellitus/epidemiology , Risk Factors , Glycated Hemoglobin , Rural Population , Prevalence , India/epidemiology , Blood Glucose , Urban Population
4.
Nicotine Tob Res ; 25(7): 1319-1329, 2023 Jun 09.
Article in English | MEDLINE | ID: mdl-37055073

ABSTRACT

INTRODUCTION: Learned smoking cues from a smoker's environment are a major cause of lapse and relapse. Quit Sense, a theory-guided Just-In-Time Adaptive Intervention smartphone app, aims to help smokers learn about their situational smoking cues and provide in-the-moment support to help manage these when quitting. METHODS: A two-arm feasibility randomized controlled trial (N = 209) to estimate parameters to inform a definitive evaluation. Smoker's willing to make a quit attempt were recruited using online paid-for adverts and randomized to "usual care" (text message referral to NHS SmokeFree website) or "usual care" plus a text message invitation to install Quit Sense. Procedures, excluding manual follow-up for nonresponders, were automated. Follow-up at 6 weeks and 6 months included feasibility, intervention engagement, smoking-related, and economic outcomes. Abstinence was verified using cotinine assessment from posted saliva samples. RESULTS: Self-reported smoking outcome completion rates at 6 months were 77% (95% CI 71%, 82%), viable saliva sample return rate was 39% (95% CI 24%, 54%), and health economic data 70% (95% CI 64%, 77%). Among Quit Sense participants, 75% (95% CI 67%, 83%) installed the app and set a quit date and, of those, 51% engaged for more than one week. The 6-month biochemically verified sustained abstinence rate (anticipated primary outcome for definitive trial), was 11.5% (12/104) among Quit Sense participants and 2.9% (3/105) for usual care (adjusted odds ratio = 4.57, 95% CIs 1.23, 16.94). No evidence of between-group differences in hypothesized mechanisms of action was found. CONCLUSIONS: Evaluation feasibility was demonstrated alongside evidence supporting the effectiveness potential of Quit Sense. IMPLICATIONS: Running a primarily automated trial to initially evaluate Quit Sense was feasible, resulting in modest recruitment costs and researcher time, and high trial engagement. When invited, as part of trial participation, to install a smoking cessation app, most participants are likely to do so, and, for those using Quit Sense, an estimated one-half will engage with it for more than 1 week. Evidence that Quit Sense may increase verified abstinence at 6-month follow-up, relative to usual care, was generated, although low saliva return rates to verify smoking status contributed to considerable imprecision in the effect size estimate.


Subject(s)
Mobile Applications , Smoking Cessation , Humans , Smoking Cessation/methods , Feasibility Studies , Smoking , Self Report
5.
Thorax ; 77(10): 950-959, 2022 10.
Article in English | MEDLINE | ID: mdl-34716281

ABSTRACT

BACKGROUND AND AIMS: The chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2) antagonist timapiprant improved lung function and asthma control in a phase 2 study, with evidence suggesting reduced exacerbations. We aimed to assess whether timapiprant attenuated or prevented asthma exacerbations induced by experimental rhinovirus (RV) infection. We furthermore hypothesised that timapiprant would dampen RV-induced type 2 inflammation and consequently improve antiviral immune responses. METHODS: Atopic patients with partially controlled asthma on maintenance inhaled corticosteroids were randomised to timapiprant (n=22) or placebo (n=22) and challenged with RV-A16 3 weeks later. The primary endpoint was the cumulative lower respiratory symptom score over the 14 days post infection. Upper respiratory symptoms, spirometry, airway hyperresponsiveness, exhaled nitric oxide, RV-A16 virus load and soluble mediators in upper and lower airways samples, and CRTH2 staining in bronchial biopsies were additionally assessed before and during RV-A16 infection. RESULTS: Six subjects discontinued the study and eight were not infected; outcomes were assessed in 16 timapiprant-treated and 14 placebo-treated, successfully infected subjects. There were no differences between treatment groups in clinical exacerbation severity including cumulative lower respiratory symptom score day 0-14 (difference 3.0 (95% CI -29.0 to 17.0), p=0.78), virus load, antiviral immune responses, or RV-A16-induced airway inflammation other than in the bronchial biopsies, where CRTH2 staining was increased during RV-A16 infection in the placebo-treated but not the timapiprant-treated group. Timapiprant had a favourable safety profile, with no deaths, serious adverse events or drug-related withdrawals. CONCLUSION: Timapiprant treatment had little impact on the clinicopathological changes induced by RV-A16 infection in partially controlled asthma.


Subject(s)
Asthma , Rhinovirus , Humans , Pilot Projects , Adrenal Cortex Hormones/therapeutic use , Inflammation
6.
BMC Med Res Methodol ; 22(1): 70, 2022 03 18.
Article in English | MEDLINE | ID: mdl-35300611

ABSTRACT

INTRODUCTION: Novel screening tests used to detect a target condition are compared against either a reference standard or other existing screening methods. However, as it is not always possible to apply the reference standard on the whole population under study, verification bias is introduced. Statistical methods exist to adjust estimates to account for this bias. We extend common methods to adjust for verification bias when multiple tests are compared to a reference standard using data from a prospective double blind screening study for prostate cancer. METHODS: Begg and Greenes method and multiple imputation are extended to include the results of multiple screening tests which determine condition verification status. These two methods are compared to the complete case analysis using the IP1-PROSTAGRAM study data. IP1-PROSTAGRAM used a paired-cohort double-blind design to evaluate the use of imaging as alternative tests to screen for prostate cancer, compared to a blood test called prostate specific antigen (PSA). Participants with positive imaging (index) and/or PSA (control) underwent a prostate biopsy (reference standard). RESULTS: When comparing complete case results to Begg and Greenes and methods of multiple imputation there is a statistically significant increase in the specificity estimates for all screening tests. Sensitivity estimates remained similar across the methods, with completely overlapping 95% confidence intervals. Negative predictive value (NPV) estimates were higher when adjusting for verification bias, compared to complete case analysis, even though the 95% confidence intervals overlap. Positive predictive value (PPV) estimates were similar across all methods. CONCLUSION: Statistical methods are required to adjust for verification bias in accuracy estimates of screening tests. Expanding Begg and Greenes method to include multiple screening tests can be computationally intensive, hence multiple imputation is recommended, especially as it can be modified for low prevalence of the target condition.


Subject(s)
Mass Screening , Prostate-Specific Antigen , Bias , Double-Blind Method , Humans , Male , Prospective Studies , Sensitivity and Specificity
7.
PLoS Med ; 17(3): e1003046, 2020 03.
Article in English | MEDLINE | ID: mdl-32142507

ABSTRACT

BACKGROUND: The majority of people do not achieve recommended levels of physical activity. There is a need for effective, scalable interventions to promote activity. Self-monitoring by pedometer is a potentially suitable strategy. We assessed the effectiveness and cost-effectiveness of a very brief (5-minute) pedometer-based intervention ('Step It Up') delivered as part of National Health Service (NHS) Health Checks in primary care. METHODS AND FINDINGS: The Very Brief Intervention (VBI) Trial was a two parallel-group, randomised controlled trial (RCT) with 3-month follow-up, conducted in 23 primary care practices in the East of England. Participants were 1,007 healthy adults aged 40 to 74 years eligible for an NHS Health Check. They were randomly allocated (1:1) using a web-based tool between October 1, 2014, and December 31, 2015, to either intervention (505) or control group (502), stratified by primary care practice. Participants were aware of study group allocation. Control participants received the NHS Health Check only. Intervention participants additionally received Step It Up: a 5-minute face-to-face discussion, written materials, pedometer, and step chart. The primary outcome was accelerometer-based physical activity volume at 3-month follow-up adjusted for sex, 5-year age group, and general practice. Secondary outcomes included time spent in different intensities of physical activity, self-reported physical activity, and economic measures. We conducted an in-depth fidelity assessment on a subsample of Health Check consultations. Participants' mean age was 56 years, two-thirds were female, they were predominantly white, and two-thirds were in paid employment. The primary outcome was available in 859 (85.3%) participants. There was no significant between-group difference in activity volume at 3 months (adjusted intervention effect 8.8 counts per minute [cpm]; 95% CI -18.7 to 36.3; p = 0.53). We found no significant between-group differences in the secondary outcomes of step counts per day, time spent in moderate or vigorous activity, time spent in vigorous activity, and time spent in moderate-intensity activity (accelerometer-derived variables); as well as in total physical activity, home-based activity, work-based activity, leisure-based activity, commuting physical activity, and screen or TV time (self-reported physical activity variables). Of the 505 intervention participants, 491 (97%) received the Step it Up intervention. Analysis of 37 intervention consultations showed that 60% of Step it Up components were delivered faithfully. The intervention cost £18.04 per participant. Incremental cost to the NHS per 1,000-step increase per day was £96 and to society was £239. Adverse events were reported by 5 intervention participants (of which 2 were serious) and 5 control participants (of which 2 were serious). The study's limitations include a participation rate of 16% and low return of audiotapes by practices for fidelity assessment. CONCLUSIONS: In this large well-conducted trial, we found no evidence of effect of a plausible very brief pedometer intervention embedded in NHS Health Checks on objectively measured activity at 3-month follow-up. TRIAL REGISTRATION: Current Controlled Trials (ISRCTN72691150).


Subject(s)
Actigraphy/instrumentation , Exercise , Fitness Trackers , Healthy Lifestyle , Primary Health Care , State Medicine , Actigraphy/economics , Adult , Aged , Cost-Benefit Analysis , England , Female , Fitness Trackers/economics , Health Care Costs , Healthy Volunteers , Humans , Male , Middle Aged , Primary Health Care/economics , State Medicine/economics , Time Factors
8.
J Med Internet Res ; 22(5): e16629, 2020 05 19.
Article in English | MEDLINE | ID: mdl-32427113

ABSTRACT

BACKGROUND: The efficacy of a highly tailored digital intervention to support medication adherence and feasibility to support clinical effectiveness as an adjunct to the primary care setting has not been evaluated. OBJECTIVE: This trial aimed to assess the behavioral efficacy of a highly tailored digital intervention to support medication adherence and to evaluate the feasibility of its clinical effectiveness, in patients with either or both hypertension and type 2 diabetes. We also examined quality of life and mechanisms of behavior change. Intervention fidelity, engagement, and satisfaction were also explored. METHODS: This was a multicenter, individually randomized controlled trial of 2 parallel groups: an intervention group that received a highly tailored text message and interactive voice response intervention for 12 weeks, and a control group that received usual care. Medication adherence was measured using self-reports and assessor-blinded practice records of a repeat prescription. Systolic blood pressure and glucose levels were assessed by nurses blinded to group allocation during practice visits at 3 months follow-up. Questionnaires obtained data to assess intervention mechanisms of action and satisfaction and digital log files captured data to evaluate fidelity and engagement. RESULTS: A total of 135 nonadherent patients (62/135, 46% female; 122/135, 90.3%; aged above 50 years) were randomly allocated in the intervention (n=79) or in the control group (n=56); of whom 13% (18/135) were lost at follow-up. Medication adherence was significantly improved in the intervention group compared with the control group (t116=2.27; P=.02, 2-tailed). Systolic blood pressure was 0.6 mmHg (95% CI -7.423 to 6.301), and hemoglobin A1c was 4.5 mmol/mol (95% CI -13.099 to 4.710) lower in the intervention group compared with the control group. Changes in intentional nonadherence and nonintentional nonadherence explained the improvements in medication adherence in the intervention group (beta=.074, SE=0.464; P=.04), but not in the control group (beta=.00, SE 1.35; P=.37). The intervention had 100% fidelity, a median of 12 days of engagement, and 76% overall satisfaction. CONCLUSIONS: Our trial is the first that has been conducted in the United Kingdom and showed that among nonadherent patients with either or both hypertension and type 2 diabetes, a highly tailored digital intervention was effective at improving treatment adherence and feasible to obtain clinically meaningful outcomes. Changes in intentional and nonintentional nonadherence predicted the improvements in medication adherence. The intervention had high fidelity, engagement, and satisfaction. Future research using a rigorous design is needed to evaluate the clinical effectiveness and cost-effectiveness of the intervention in primary care. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN) 10668149; http://www.controlled-trials.com/ISRCTN10668149.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Hypertension/drug therapy , Medication Adherence/statistics & numerical data , Quality of Life/psychology , Text Messaging/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Diabetes Mellitus, Type 2/psychology , Feasibility Studies , Female , Humans , Hypertension/psychology , Male , Middle Aged , Treatment Outcome , United Kingdom , Young Adult
9.
Crit Care ; 23(1): 156, 2019 05 03.
Article in English | MEDLINE | ID: mdl-31053084

ABSTRACT

BACKGROUND: Randomised controlled trials (RCTs) enrolling patients with sepsis or acute respiratory distress syndrome (ARDS) generate heterogeneous trial populations. Non-random variation in the treatment effect of an intervention due to differences in the baseline risk of death between patients in a population represents one form of heterogeneity of treatment effect (HTE). We assessed whether HTE in two sepsis and one ARDS RCTs could explain indeterminate trial results and inform future trial design. METHODS: We assessed HTE for vasopressin, hydrocortisone and levosimendan in sepsis and simvastatin in ARDS patients, on 28-day mortality, using the total Acute Physiology And Chronic Health Evaluation II (APACHE II) score as the baseline risk measurement, comparing above (high) and below (low) the median score. Secondary risk measures were the acute physiology component of APACHE II and predicted risk of mortality using the APACHE II score. HTE was quantified both in additive (difference in risk difference (RD)) and multiplicative (ratio of relative risks (RR)) scales using estimated treatment differences from a logistic regression model with treatment risk as the interaction term. RESULTS: The ratio of the odds of death in the highest APACHE II quartile was 4.9 to 7.4 times compared to the lowest quartile, across the three trials. We did not observe HTE for vasopressin, hydrocortisone and levosimendan in the two sepsis trials. In the HARP-2 trial, simvastatin reduced mortality in the low APACHE II group and increased mortality in the high APACHE II group (difference in RD = 0.34 (0.12, 0.55) (p = 0.02); ratio of RR 3.57 (1.77, 7.17) (p < 0.001). The HTE patterns were inconsistent across the secondary risk measures. The sensitivity analyses of HTE effects for vasopressin, hydrocortisone and levosimendan were consistent with the main analyses and attenuated for simvastatin. CONCLUSIONS: We assessed HTE in three recent ICU RCTs, using multivariable baseline risk of death models. There was considerable within-trial variation in the baseline risk of death. We observed potential HTE for simvastatin in ARDS, but no evidence of HTE for vasopressin, hydrocortisone or levosimendan in the two sepsis trials. Our findings could be explained either by true lack of HTE (no benefit of vasopressin, hydrocortisone or levosimendan vs comparator for any patient subgroups) or by lack of power to detect HTE. Our results require validation using similar trial databases.


Subject(s)
Critical Illness/therapy , Guideline Adherence/trends , Respiratory Distress Syndrome/drug therapy , Sepsis/drug therapy , Treatment Outcome , APACHE , Adult , Aged , Anti-Inflammatory Agents/therapeutic use , Cardiotonic Agents/therapeutic use , Critical Illness/mortality , Female , Hospital Mortality/trends , Humans , Hydrocortisone/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Intensive Care Units/organization & administration , Intensive Care Units/statistics & numerical data , Male , Middle Aged , Randomized Controlled Trials as Topic , Respiratory Distress Syndrome/mortality , Sepsis/mortality , Simendan/therapeutic use , Simvastatin/therapeutic use , Vasoconstrictor Agents/therapeutic use , Vasopressins/therapeutic use
10.
Lancet ; 389(10085): 2193-2203, 2017 Jun 03.
Article in English | MEDLINE | ID: mdl-28494920

ABSTRACT

BACKGROUND: Proliferative diabetic retinopathy is the most common cause of severe sight impairment in people with diabetes. Proliferative diabetic retinopathy has been managed by panretinal laser photocoagulation (PRP) for the past 40 years. We report the 1 year safety and efficacy of intravitreal aflibercept. METHODS: In this phase 2b, single-blind, non-inferiority trial (CLARITY), adults (aged ≥18 years) with type 1 or 2 diabetes and previously untreated or post-laser treated active proliferative diabetic retinopathy were recruited from 22 UK ophthalmic centres. Patients were randomly assigned (1:1) to repeated intravitreal aflibercept (2 mg/0·05 mL at baseline, 4 weeks, and 8 weeks, and from week 12 patients were reviewed every 4 weeks and aflibercept injections were given as needed) or PRP standard care (single spot or mutlispot laser at baseline, fractionated fortnightly thereafter, and from week 12 patients were assessed every 8 weeks and treated with PRP as needed) for 52 weeks. Randomisation was by minimisation with a web-based computer generated system. Primary outcome assessors were masked optometrists. The treating ophthalmologists and participants were not masked. The primary outcome was defined as a change in best-corrected visual acuity at 52 weeks with a linear mixed-effect model that estimated adjusted treatment effects at both 12 weeks and 52 weeks, having excluded fluctuations in best corrected visual acuity owing to vitreous haemorrhage. This modified intention-to-treat analysis was reapplied to the per protocol participants. The non-inferiority margin was prespecified as -5 Early Treatment Diabetic Retinopathy Study letters. Safety was assessed in all participants. This trial is registered with ISRCTN registry, number 32207582. FINDINGS: We recruited 232 participants (116 per group) between Aug 22, 2014 and Nov 30, 2015. 221 participants (112 in aflibercept group, 109 in PRP group) contributed to the modified intention-to-treat model, and 210 participants (104 in aflibercept group and 106 in PRP group) within per protocol. Aflibercept was non-inferior and superior to PRP in both the modified intention-to-treat population (mean best corrected visual acuity difference 3·9 letters [95% CI 2·3-5·6], p<0·0001) and the per-protocol population (4·0 letters [2·4-5·7], p<0·0001). There were no safety concerns. The 95% CI adjusted difference between groups was more than the prespecified acceptable margin of -5 letters at both 12 weeks and 52 weeks. INTERPRETATION: Patients with proliferative diabetic retinopathy who were treated with intravitreal aflibercept had an improved outcome at 1 year compared with those treated with PRP standard care. FUNDING: The Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health Research partnership.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Diabetic Retinopathy/therapy , Laser Coagulation/methods , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Adult , Aged , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/adverse effects , Diabetic Retinopathy/physiopathology , Female , Humans , Intravitreal Injections , Laser Coagulation/adverse effects , Male , Middle Aged , Receptors, Vascular Endothelial Growth Factor/administration & dosage , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/adverse effects , Sensitivity and Specificity , Single-Blind Method , Treatment Outcome , Visual Acuity/drug effects
11.
Biostatistics ; 17(4): 634-49, 2016 10.
Article in English | MEDLINE | ID: mdl-26993061

ABSTRACT

The problem of selection bias has long been recognized in the analysis of two-stage trials, where promising candidates are selected in stage 1 for confirmatory analysis in stage 2. To efficiently correct for bias, uniformly minimum variance conditionally unbiased estimators (UMVCUEs) have been proposed for a wide variety of trial settings, but where the population parameter estimates are assumed to be independent. We relax this assumption and derive the UMVCUE in the multivariate normal setting with an arbitrary known covariance structure. One area of application is the estimation of odds ratios (ORs) when combining a genome-wide scan with a replication study. Our framework explicitly accounts for correlated single nucleotide polymorphisms, as might occur due to linkage disequilibrium. We illustrate our approach on the measurement of the association between 11 genetic variants and the risk of Crohn's disease, as reported in Parkes and others (2007. Sequence variants in the autophagy gene IRGM and multiple other replicating loci contribute to Crohn's disease susceptibility. Nat. Gen. 39: (7), 830-832.), and show that the estimated ORs can vary substantially if both selection and correlation are taken into account.


Subject(s)
Genome-Wide Association Study/standards , Polymorphism, Single Nucleotide , Selection Bias , Crohn Disease/genetics , Humans
12.
Stat Med ; 35(22): 3907-22, 2016 09 30.
Article in English | MEDLINE | ID: mdl-27103068

ABSTRACT

Seamless phase II/III clinical trials offer an efficient way to select an experimental treatment and perform confirmatory analysis within a single trial. However, combining the data from both stages in the final analysis can induce bias into the estimates of treatment effects. Methods for bias adjustment developed thus far have made restrictive assumptions about the design and selection rules followed. In order to address these shortcomings, we apply recent methodological advances to derive the uniformly minimum variance conditionally unbiased estimator for two-stage seamless phase II/III trials. Our framework allows for the precision of the treatment arm estimates to take arbitrary values, can be utilised for all treatments that are taken forward to phase III and is applicable when the decision to select or drop treatment arms is driven by a multiplicity-adjusted hypothesis testing procedure. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.


Subject(s)
Clinical Trials, Phase II as Topic , Clinical Trials, Phase III as Topic , Research Design , Bias , Biometry , Humans
13.
BMC Public Health ; 16(1): 1033, 2016 09 30.
Article in English | MEDLINE | ID: mdl-27716297

ABSTRACT

BACKGROUND: Very brief interventions (VBIs) for physical activity are promising, but there is uncertainty about their potential effectiveness and cost. We assessed potential efficacy, feasibility, acceptability, and cost of three VBIs in primary care, in order to select the most promising intervention for evaluation in a subsequent large-scale RCT. METHODS: Three hundred and ninety four adults aged 40-74 years were randomised to a Motivational (n = 83), Pedometer (n = 74), or Combined (n = 80) intervention, delivered immediately after a preventative health check in primary care, or control (Health Check only; n = 157). Potential efficacy was measured as the probability of a positive difference between an intervention arm and the control arm in mean physical activity, measured by accelerometry at 4 weeks. RESULTS: For the primary outcome the estimated effect sizes (95 % CI) relative to the Control arm for the Motivational, Pedometer and Combined arms were respectively: +20.3 (-45.0, +85.7), +23.5 (-51.3, +98.3), and -3.1 (-69.3, +63.1) counts per minute. There was a73% probability of a positive effect on physical activity for each of the Motivational and Pedometer VBIs relative to control, but only 46 % for the Combined VBI. Only the Pedometer VBI was deliverable within 5 min. All VBIs were acceptable and low cost. CONCLUSIONS: Based on the four criteria, the Pedometer VBI was selected for evaluation in a large-scale trial. TRIAL REGISTRATION: Current Controlled Trials ISRCTN02863077 . Retrospectively registered 05/10/2012.


Subject(s)
Exercise , Health Behavior , Health Promotion/methods , Primary Health Care , Actigraphy , Adult , Feasibility Studies , Female , Humans , Male , Middle Aged , Motivation , Treatment Outcome
14.
Am J Public Health ; 105(9): e54-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26180980

ABSTRACT

OBJECTIVES: We examined the probability of an obese person attaining normal body weight. METHODS: We drew a sample of individuals aged 20 years and older from the United Kingdom's Clinical Practice Research Datalink from 2004 to 2014. We analyzed data for 76,704 obese men and 99,791 obese women. We excluded participants who received bariatric surgery. We estimated the probability of attaining normal weight or 5% reduction in body weight. RESULTS: During a maximum of 9 years' follow-up, 1283 men and 2245 women attained normal body weight. In simple obesity (body mass index = 30.0-34.9 kg/m(2)), the annual probability of attaining normal weight was 1 in 210 for men and 1 in 124 for women, increasing to 1 in 1290 for men and 1 in 677 for women with morbid obesity (body mass index = 40.0-44.9 kg/m(2)). The annual probability of achieving a 5% weight reduction was 1 in 8 for men and 1 in 7 for women with morbid obesity. CONCLUSIONS: The probability of attaining normal weight or maintaining weight loss is low. Obesity treatment frameworks grounded in community-based weight management programs may be ineffective.


Subject(s)
Ideal Body Weight , Obesity/physiopathology , Weight Loss , Adult , Aged , Body Mass Index , Cohort Studies , Female , Humans , Male , Middle Aged , Obesity, Morbid/physiopathology , Probability , United Kingdom
15.
Stat Med ; 34(8): 1417-37, 2015 Apr 15.
Article in English | MEDLINE | ID: mdl-25645331

ABSTRACT

When developing a new diagnostic test for a disease, there are often multiple candidate classifiers to choose from, and it is unclear if any will offer an improvement in performance compared with current technology. A two-stage design can be used to select a promising classifier (if one exists) in stage one for definitive validation in stage two. However, estimating the true properties of the chosen classifier is complicated by the first stage selection rules. In particular, the usual maximum likelihood estimator (MLE) that combines data from both stages will be biased high. Consequently, confidence intervals and p-values flowing from the MLE will also be incorrect. Building on the results of Pepe et al. (SIM 28:762-779), we derive the most efficient conditionally unbiased estimator and exact confidence intervals for a classifier's sensitivity in a two-stage design with arbitrary selection rules; the condition being that the trial proceeds to the validation stage. We apply our estimation strategy to data from a recent family history screening tool validation study by Walter et al. (BJGP 63:393-400) and are able to identify and successfully adjust for bias in the tool's estimated sensitivity to detect those at higher risk of breast cancer.


Subject(s)
Breast Neoplasms/diagnosis , Early Detection of Cancer/standards , Epidemiologic Research Design , Family Health/statistics & numerical data , Analysis of Variance , Bias , Biomarkers/analysis , Computer Simulation , Confidence Intervals , Early Detection of Cancer/methods , Early Detection of Cancer/statistics & numerical data , Female , Humans , Likelihood Functions , Reproducibility of Results , Risk Assessment/methods , Risk Assessment/standards , Risk Assessment/statistics & numerical data , Statistics, Nonparametric , Surveys and Questionnaires/standards
16.
Ann Behav Med ; 49(1): 7-17, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24806469

ABSTRACT

BACKGROUND: Meta-analyses have identified promising behavior change techniques (BCTs) in changing obesity-related behaviors from intervention descriptions. However, it is unclear whether these BCTs are used by intervention participants and are related to outcomes. PURPOSE: The purpose of this study is to investigate BCT use by participants of an intervention targeting physical activity and diet and whether BCT use was related to behavior change and weight loss. METHODS: Intervention participants (N = 239; 40-69 years) with recently diagnosed type 2 diabetes in the ADDITION-Plus trial received a theory-based intervention which taught them a range of BCTs. BCT usage was reported at 1 year. RESULTS: Thirty-six percent of the participants reported using all 16 intervention BCTs. Use of a higher number of BCTs and specific BCTs (e.g., goal setting) were associated with a reduction in body mass index (BMI). CONCLUSIONS: BCT use was associated with weight loss. Future research should identify strategies to promote BCT use in daily life. ( TRIAL REGISTRATION: ISRCTN99175498.).


Subject(s)
Behavior Therapy/methods , Body Mass Index , Diabetes Mellitus, Type 2/rehabilitation , Diet , Health Behavior , Adult , Aged , Female , Humans , Male , Middle Aged , Treatment Outcome
17.
Ann Fam Med ; 13(2): 149-57, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25755036

ABSTRACT

PURPOSE: There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors. METHODS: We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis. RESULTS: Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71-1.15); SF-8 physical health summary score as an indicator of self-rated health status (ß -0.33, 95% CI, -1.80 to 1.14); EQ-5D visual analogue score (ß: 0.80, 95% CI, -1.28 to 2.87); total physical activity (ß 0.50, 95% CI, -4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (ß 0.14, 95% CI, -1.07 to 1.35). CONCLUSIONS: Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years.


Subject(s)
Alcohol Drinking/epidemiology , Diabetes Mellitus, Type 2/diagnosis , Health Status , Motor Activity , Myocardial Infarction/epidemiology , Smoking/epidemiology , Stroke/epidemiology , Adult , Aged , Cardiovascular Diseases/epidemiology , Diabetes Mellitus, Type 2/therapy , England/epidemiology , Female , Health Behavior , Humans , Longitudinal Studies , Male , Mass Screening , Middle Aged , Self Report , Surveys and Questionnaires
18.
Diabetologia ; 57(7): 1308-19, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24759957

ABSTRACT

AIMS/HYPOTHESIS: The aim of this study was to assess whether or not a theory-based behaviour change intervention delivered by trained and quality-assured lifestyle facilitators can achieve and maintain improvements in physical activity, dietary change, medication adherence and smoking cessation in people with recently diagnosed type 2 diabetes. METHODS: An explanatory randomised controlled trial was conducted in 34 general practices in Eastern England (Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care-Plus [ADDITION-Plus]). In all, 478 patients meeting eligibility criteria (age 40 to 69 years with recently diagnosed screen or clinically detected diabetes) were individually randomised to receive either intensive treatment (n = 239) or intensive treatment plus a theory-based behaviour change intervention led by a facilitator external to the general practice team (n = 239). Randomisation was central and independent using a partial minimisation procedure to balance stratifiers between treatment arms. Facilitators taught patients skills to facilitate change in and maintenance of key health behaviours, including goal setting, self-monitoring and building habits. Primary outcomes included physical activity energy expenditure (individually calibrated heart rate monitoring and movement sensing), change in objectively measured fruit and vegetable intake (plasma vitamin C), medication adherence (plasma drug levels) and smoking status (plasma cotinine levels) at 1 year. Measurements, data entry and laboratory analysis were conducted with staff unaware of participants' study group allocation. RESULTS: Of 475 participants still alive, 444 (93%; intervention group 95%, comparison group 92%) attended 1-year follow-up. There were no significant differences between groups in physical activity (difference: +1.50 kJ kg(-1) day(-1); 95% CI -1.74, 4.74), plasma vitamin C (difference: -3.84 µmol/l; 95% CI -8.07, 0.38), smoking (OR 1.37; 95% CI 0.77, 2.43) and plasma drug levels (difference in metformin levels: -119.5 µmol/l; 95% CI -335.0, 95.9). Cardiovascular risk factors and self-reported behaviour improved in both groups with no significant differences between groups. CONCLUSIONS/INTERPRETATION: For patients with recently diagnosed type 2 diabetes receiving intensive treatment in UK primary care, a facilitator-led individually tailored behaviour change intervention did not improve objectively measured health behaviours or cardiovascular risk factors over 1 year. TRIAL REGISTRATION: ISRCTN99175498 FUNDING: The trial is supported by the Medical Research Council, the Wellcome Trust, National Health Service R&D support funding (including the Primary Care Research and Diabetes Research Networks) and National Institute of Health Research under its Programme Grants for Applied Research scheme. The Primary Care Unit is supported by NIHR Research funds. Bio-Rad provided equipment for HbA1c testing during the screening phase.


Subject(s)
Diabetes Mellitus, Type 2/therapy , Health Behavior , Hypoglycemic Agents/therapeutic use , Life Style , Medication Adherence , Smoking Cessation , Adult , Aged , Combined Modality Therapy , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/psychology , Female , Humans , Male , Middle Aged , Risk Factors , Treatment Outcome
19.
BMC Med ; 12: 194, 2014 Oct 31.
Article in English | MEDLINE | ID: mdl-25358424

ABSTRACT

BACKGROUND: Breathlessness is common in advanced cancer. The Breathlessness Intervention Service (BIS) is a multi-disciplinary complex intervention theoretically underpinned by a palliative care approach, utilising evidence-based non-pharmacological and pharmacological interventions to support patients with advanced disease. We sought to establish whether BIS was more effective, and cost-effective, for patients with advanced cancer and their carers than standard care. METHODS: A single-centre Phase III fast-track single-blind mixed-method randomised controlled trial (RCT) of BIS versus standard care was conducted. Participants were randomised to one of two groups (randomly permuted blocks). A total of 67 patients referred to BIS were randomised (intervention arm n = 35; control arm n = 32 received BIS after a two-week wait); 54 completed to the key outcome measurement. The primary outcome measure was a 0 to 10 numerical rating scale for patient distress due to breathlessness at two-weeks. Secondary outcomes were evaluated using the Chronic Respiratory Questionnaire, Hospital Anxiety and Depression Scale, Client Services Receipt Inventory, EQ-5D and topic-guided interviews. RESULTS: BIS reduced patient distress due to breathlessness (primary outcome: -1.29; 95% CI -2.57 to -0.005; P = 0.049) significantly more than the control group; 94% of respondents reported a positive impact (51/53). BIS reduced fear and worry, and increased confidence in managing breathlessness. Patients and carers consistently identified specific and repeatable aspects of the BIS model and interventions that helped. How interventions were delivered was important. BIS legitimised breathlessness and increased knowledge whilst making patients and carers feel 'not alone'. BIS had a 66% likelihood of better outcomes in terms of reduced distress due to breathlessness at lower health/social care costs than standard care (81% with informal care costs included). CONCLUSIONS: BIS appears to be more effective and cost-effective in advanced cancer than standard care. TRIAL REGISTRATION: RCT registration at ClinicalTrials.gov NCT00678405 (May 2008) and Current Controlled Trials ISRCTN04119516 (December 2008).


Subject(s)
Dyspnea/therapy , Neoplasms/complications , Palliative Care/methods , Adult , Aged , Aged, 80 and over , Anxiety , Caregivers/psychology , Cost-Benefit Analysis , Dyspnea/etiology , Female , Health Care Costs , Humans , Male , Middle Aged , Occupational Therapy , Outcome Assessment, Health Care , Palliative Care/economics , Physical Therapy Modalities , Single-Blind Method , Surveys and Questionnaires
20.
Ann Behav Med ; 48(3): 293-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24573909

ABSTRACT

BACKGROUND: Electronic monitoring is recommended for accurate measurement of medication adherence but a possible limitation is that it may influence adherence. PURPOSE: To test the reactive effect of electronic monitoring in a randomized controlled trial. METHODS: A total of 226 adults with type 2 diabetes and HbA1c ≥58 mmol/mol were randomized to receiving their main oral glucose lowering medication in electronic containers or standard packaging. The primary outcomes were self-reported adherence measured with the MARS (Medication Adherence Report Scale; range 5-25) and HbA1c at 8 weeks. RESULTS: Non-significantly higher adherence and lower HbA1c were observed in the electronic container group (differences in means, adjusting for baseline value: MARS, 0.4 [95 % CI -0.1 to 0.8, p = 0.11]; HbA1c (mmol/mol), -1.02 [-2.73 to 0.71, p = 0.25]). CONCLUSIONS: Electronic containers may lead to a small increase in adherence but this potential limitation is outweighed by their advantages. Our findings support electronic monitoring as the method of choice in research on medication adherence. (Trial registration Current Controlled Trials ISRCT N30522359).


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Drug Packaging/standards , Hypoglycemic Agents/administration & dosage , Medication Adherence , Aged , Drug Packaging/instrumentation , Electrical Equipment and Supplies/standards , Female , Glycated Hemoglobin/analysis , Humans , Male , Middle Aged
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