First large-scale study of antimicrobial susceptibility data, and genetic resistance determinants, in Fusobacterium necrophorum highlighting the importance of continuing focused susceptibility trend surveillance

Objectives: The objective of the study was to explore antimicrobial resistance gene determinant, and phenotypic antibiotic susceptibility, data for Fusobacterium necrophorum from a collection of UK strains. In addition, antimicrobial resistance genes detected in publicly available assembled whole genome sequences were investigated for comparison.Methods: Three hundred and eighty five F. necrophorum strains (1982-2019) were revived from cryovials (Prolab). Subsequent to sequencing (Illumina) and quality checking, 374 whole genomes were available for analysis. These genomes, in addition to publicly available assembled F. necrophorum genetic data, were interrogated using BioNumerics (bioMérieux; v 8.1), for the presence of known antimicrobial resistance genes (ARGs). Agar dilution susceptibility results for 313 F. necrophorum isolates (2016-2021) were also examined.Results: The phenotypic antibiotic test data for the 313 contemporary strains demonstrated potential resistance to penicillin, without increased dosing, in only three isolates. Otherwise, all strains were susceptible to ceftriaxone, clindamycin, co-amoxiclav, meropenem, metronidazole, penicillin and piperacillin/tazobactam, using EUCAST (v 11.0) interpretive guidance. The tet(O), tet(M), tet(40), aph(3’)-III, ant(6)-la and blaOXA-85 ARGs were present in publicly available assembled genomes. tet(M), tet(32), erm(A) and erm(B) were found within the UK strains, with correspondingly raised clindamycin and tetracycline minimum inhibitory concentrations.Conclusions: Current antibiotics recommended for the treatment of infections caused by F. necrophorum, including Lemierre’s disease, are likely to be effective in most cases. However, with evidence of potential ARG transmission from oral bacteria, and the detection of a transposon-mediated beta-lactamase resistance determinant in F. necrophorum, surveillance of both phenotypic and genotypic antimicrobial susceptibility trends must continue, and increase.<br/

Association between trial registration and positive study findings: cross sectional study (Epidemiological Study of Randomized Trials—ESORT)

Objective To assess whether randomised controlled trials (RCTs) that were registered were less likely to report positive study findings compared with RCTs that were not registered and whether the association varied by funding source. Design Cross sectional study. Study sample All primary RCTs published in December 2012 and indexed in PubMed by November 2013. Trial registration was determined based on the report of a trial registration number in published RCTs or the identification of the trial in a search of trial registries. Trials were separated into prospectively and retrospectively registered studies. Main outcome measure Association between trial registration and positive study findings. Results 1122 eligible RCTs were identified, of which 593 (52.9%) were registered and 529 (47.1%) were not registered. Overall, registration was marginally associated with positive study findings (adjusted risk ratio 0.87, 95% confidence interval 0.78 to 0.98), even with stratification as prospectively and retrospectively registered trials (0.87, 0.74 to 1.03 and 0.88, 0.78 to 1.00, respectively). The interaction term between overall registration and funding source was marginally statistically significant and relative risk estimates were imprecise (0.75, 0.63 to 0.89 for non-industry funded and 1.03, 0.79 to 1.36 for industry funded, P interaction=0.046). Furthermore, a statistically significant interaction was not maintained in sensitivity analyses. Within each stratum of funding source, relative risk estimates were also imprecise for the association between positive study findings and prospective and retrospective registration. Conclusion Among published RCTs, there was little evidence of a difference in positive study findings between registered and non-registered clinical trials, even with stratification by timing of registration. Relative risk estimates were imprecise in subgroups of non-industry and industry funded trials

Anti-tumour necrosis factor therapy for Dupuytren's Disease: a randomised dose response proof of concept phase 2a clinical trial

Background Dupuytren's disease is a common fibrotic condition of the hand that causes irreversible flexion contractures of the fingers, with no approved therapy for early stage disease. Our previous analysis of surgically-excised tissue defined tumour necrosis factor (TNF) as a potential therapeutic target. Here we assessed the efficacy of injecting nodules of Dupuytren's disease with a TNF inhibitor. Methods Patients were randomised to receive adalimumab on one occasion in dose cohorts of 15 mg in 0.3 ml, 35 mg in 0.7 ml, or 40 mg in 0.4 ml, or an equivalent volume of placebo in a 3:1 ratio. Two weeks later the injected tissue was surgically excised and analysed. The primary outcome measure was levels of mRNA expression for α-smooth muscle actin (ACTA2). Secondary outcomes included levels of α-SMA and collagen proteins. The trial was registered with ClinicalTrial.gov (NCT03180957) and the EudraCT (2015-001780-40). Findings We recruited 28 patients, 8 assigned to the 15 mg, 12 to the 35 mg and 8 to the 40 mg adalimumab cohorts. There was no change in mRNA levels for ACTA2, COL1A1, COL3A1 and CDH11. Levels of α-SMA protein expression in patients treated with 40 mg adalimumab (1.09 ± 0.09 ng per μg of total protein) were significantly lower (p = 0.006) compared to placebo treated patients (1.51 ± 0.09 ng/μg). The levels of procollagen type I protein expression were also significantly lower (p < 0.019) in the sub group treated with 40 mg adalimumab (474 ± 84 pg/μg total protein) compared with placebo (817 ± 78 pg/μg). There were two serious adverse events, both considered unrelated to the study drug. Interpretation In this dose-ranging study, injection of 40 mg of adalimumab in 0.4 ml resulted in down regulation of the myofibroblast phenotype as evidenced by reduction in expression of α-SMA and type I procollagen proteins at 2 weeks. These data form the basis of an ongoing phase 2b clinical trial assessing the efficacy of intranodular injection of 40 mg adalimumab in 0.4 ml compared to an equivalent volume of placebo in patients with early stage Dupuytren's disease

Aerobic and strength training exercise programme for cognitive impairment in people with mild to moderate dementia : the DAPA RCT

Background Approximately 670,000 people in the UK have dementia. Previous literature suggests that physical exercise could slow dementia symptom progression. Objectives To estimate the clinical effectiveness and cost-effectiveness of a bespoke exercise programme, in addition to usual care, on the cognitive impairment (primary outcome), function and health-related quality of life (HRQoL) of people with mild to moderate dementia (MMD) and carer burden and HRQoL. Design Intervention development, systematic review, multicentred, randomised controlled trial (RCT) with a parallel economic evaluation and qualitative study. Setting 15 English regions. Participants People with MMD living in the community. Intervention A 4-month moderate- to high-intensity, structured exercise programme designed specifically for people with MMD, with support to continue unsupervised physical activity thereafter. Exercises were individually prescribed and progressed, and participants were supervised in groups. The comparator was usual practice. Main outcome measures The primary outcome was the Alzheimer’s Disease Assessment Scale – Cognitive Subscale (ADAS-Cog). The secondary outcomes were function [as measured using the Bristol Activities of Daily Living Scale (BADLS)], generic HRQoL [as measured using the EuroQol-5 Dimensions, three-level version (EQ-5D-3L)], dementia-related QoL [as measured using the Quality of Life in Alzheimer’s Disease (QoL-AD) scale], behavioural symptoms [as measured using the Neuropsychiatric Inventory (NPI)], falls and fractures, physical fitness (as measured using the 6-minute walk test) and muscle strength. Carer outcomes were HRQoL (Quality of Life in Alzheimer’s Disease) (as measured using the EQ-5D-3L) and carer burden (as measured using the Zarit Burden Interview). The economic evaluation was expressed in terms of incremental cost per quality-adjusted life-year (QALY) gained from a NHS and Personal Social Services perspective. We measured health and social care use with the Client Services Receipt Inventory. Participants were followed up for 12 months. Results Between February 2013 and June 2015, 494 participants were randomised with an intentional unequal allocation ratio: 165 to usual care and 329 to the intervention. The mean age of participants was 77 years [standard deviation (SD) 7.9 years], 39% (193/494) were female and the mean baseline ADAS-Cog score was 21.5 (SD 9.0). Participants in the intervention arm achieved high compliance rates, with 65% (214/329) attending between 75% and 100% of sessions. Outcome data were obtained for 85% (418/494) of participants at 12 months, at which point a small, statistically significant negative treatment effect was found in the primary outcome, ADAS-Cog (patient reported), with a mean difference of –1.4 [95% confidence interval (CI) –2.62 to –0.17]. There were no treatment effects for any of the other secondary outcome measures for participants or carers: for the BADLS there was a mean difference of –0.6 (95% CI –2.05 to 0.78), for the EQ-5D-3L a mean difference of –0.002 (95% CI –0.04 to 0.04), for the QoL-AD scale a mean difference of 0.7 (95% CI –0.21 to 1.65) and for the NPI a mean difference of –2.1 (95% CI –4.83 to 0.65). Four serious adverse events were reported. The exercise intervention was dominated in health economic terms. Limitations In the absence of definitive guidance and rationale, we used a mixed exercise programme. Neither intervention providers nor participants could be masked to treatment allocation. Conclusions This is a large well-conducted RCT, with good compliance to exercise and research procedures. A structured exercise programme did not produce any clinically meaningful benefit in function or HRQoL in people with dementia or on carer burden

Improving the specification of the target difference in the sample size calculation of a randomised trial of treatments for osteoarthritis

The sample size of a clinical trial is the number of participants the trial aims to recruit. Sample size is a critical aspect of clinical trial design and has ethical and financial implications. The sample size depends on the target difference, the difference in outcome that the trial is powered to detect. This thesis aims to improve methods for specifying the target difference in randomised trials of osteoarthritis. I conducted a systematic review of sample size calculations in hip and knee osteoarthritis trials published in 2016. It found that most sample size calculations were poorly reported and could not be reproduced. The target difference in the sample size calculation was commonly justified by a published minimum clinically important difference (MCID). Several versions of the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) were commonly used in hip and knee osteoarthritis trials. It was often unclear which version was used, hindering interpretation of trial results. I conducted a discrete choice experiment examining patient preferences when choosing between osteoarthritis medications. Duration of treatment effect was shown to be important to participants, viewed with similar importance to the amount of symptom relief provided and risks of the treatment. I analysed a cohort of people with osteoarthritis and showed that MCID estimates for the WOMAC varied across different follow-up time points. However, there was no visual trend in the change in MCID estimates over time. Longitudinal methods were feasible to calculate MCID estimates, but did not improve precision. A simulation study that I conducted found that the pattern of the treatment effect (its duration and consistency) affected the optimal statistical method of analysis for a randomised trial using the WOMAC as the primary outcome. Future research is needed to examine whether the findings are generalisable to different datasets, outcome measures and health conditions.</p

Improving the specification of the target difference in the sample size calculation of a randomised trial of treatments for osteoarthritis

The sample size of a clinical trial is the number of participants the trial aims to recruit. Sample size is a critical aspect of clinical trial design and has ethical and financial implications. The sample size depends on the target difference, the difference in outcome that the trial is powered to detect. This thesis aims to improve methods for specifying the target difference in randomised trials of osteoarthritis. I conducted a systematic review of sample size calculations in hip and knee osteoarthritis trials published in 2016. It found that most sample size calculations were poorly reported and could not be reproduced. The target difference in the sample size calculation was commonly justified by a published minimum clinically important difference (MCID). Several versions of the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) were commonly used in hip and knee osteoarthritis trials. It was often unclear which version was used, hindering interpretation of trial results. I conducted a discrete choice experiment examining patient preferences when choosing between osteoarthritis medications. Duration of treatment effect was shown to be important to participants, viewed with similar importance to the amount of symptom relief provided and risks of the treatment. I analysed a cohort of people with osteoarthritis and showed that MCID estimates for the WOMAC varied across different follow-up time points. However, there was no visual trend in the change in MCID estimates over time. Longitudinal methods were feasible to calculate MCID estimates, but did not improve precision. A simulation study that I conducted found that the pattern of the treatment effect (its duration and consistency) affected the optimal statistical method of analysis for a randomised trial using the WOMAC as the primary outcome. Future research is needed to examine whether the findings are generalisable to different datasets, outcome measures and health conditions.</p

Sample size calculation in osteoarthritis trials: A systematic review protocol (Version details: Osteoarthritis sample size systematic review protocol_BCopsey_16May2017.docx)

Protocol for a systematic review of sample size calculation in osteoarthritis trials<div><br></div><div>Updated: 16 May 2017</div><div>Changes: Added non-English language and mixed populations as exclusion criteria, clarified subgroup categorisations and refine methods of subgroup analysis.</div