Factors affecting ventriculoperitoneal shunt revision: a post hoc analysis of the British Antibiotic and Silver Impregnated Catheter Shunt multicenter randomized controlled trial

OBJECTIVE

The British Antibiotic and Silver Impregnated Catheter Shunt (BASICS) trial established level I evidence of the superiority of antibiotic-impregnated catheters in the prevention of infection of newly implanted ventriculoperitoneal shunts (VPSs). A wealth of patient, shunt, and surgery-specific data were collected from trial participants beyond that of the prespecified trial objectives.

METHODS

This post hoc analysis of the BASICS survival data explores the impact of patient age, hydrocephalus etiology, catheter type, valve type, and previous external ventricular drain on the risk of infection or mechanical failure. Time to failure was analyzed using Fine and Gray survival regression models for competing risk.

RESULTS

Among 1594 participants, 75 patients underwent revision for infection and 323 for mechanical failure. Multivariable analysis demonstrated an increased risk of shunt infection associated with patient ages < 1 month (subdistribution hazard ratio [sHR] 4.48, 95% CI 2.06-9.72; p < 0.001) and 1 month to < 1 year (sHR 2.67, 95% CI 1.27-5.59; p = 0.009), as well as for adults with posthemorrhagic hydrocephalus (sHR 2.75, 95% CI 1.21-6.26; p = 0.016). Age ≥ 65 years was found to be independently associated with reduced infection risk (sHR 0.26, 95% CI 0.10-0.69; p = 0.007). Antibiotic-impregnated catheter use was also associated with reduced infection risk (sHR 0.43, 95% CI 0.22-0.84; p = 0.014). Independent risk factors predisposing to mechanical failure were age < 1 month (sHR 1.51, 95% CI 1.03-2.21; p = 0.032) and 1 month to < 1 year (sHR 1.31, 95% CI 0.95-1.81; p = 0.046). Age ≥ 65 years was demonstrated to be the only independent protective factor against mechanical failure risk (sHR 0.64, 95% CI 0.40-0.94; p = 0.024).

CONCLUSIONS

Age is the predominant risk for VPS revision for infection and/or mechanical failure, with neonates and infants being the most vulnerable.

Managing clustering effects and learning effects in the design and analysis of randomised surgical trials: a review of existing guidance

BACKGROUND

The complexities associated with delivering randomised surgical trials, such as clustering effects, by centre or surgeon, and surgical learning, are well known. Despite this, approaches used to manage these complexities, and opinions on these, vary. Guidance documents have been developed to support clinical trial design and reporting. This work aimed to identify and examine existing guidance and consider its relevance to clustering effects and learning curves within surgical trials.

METHODS

A review of existing guidelines, developed to inform the design and analysis of randomised controlled trials, is undertaken. Guidelines were identified using an electronic search, within the Equator Network, and by a targeted search of those endorsed by leading UK funding bodies, regulators, and medical journals. Eligible documents were compared against pre-specified key criteria to identify gaps or inconsistencies in recommendations.

RESULTS

Twenty-eight documents were eligible (12 Equator Network; 16 targeted search). Twice the number of guidance documents targeted design (n/N=20/28, 71%) than analysis (n/N=10/28, 36%). Managing clustering by centre through design was well documented. Clustering by surgeon had less coverage and contained some inconsistencies. Managing the surgical learning curve, or changes in delivery over time, through design was contained within several documents (n/N=8/28, 29%), of which one provided guidance on reporting this and restricted to early phase studies only. Methods to analyse clustering effects and learning were provided in five and four documents respectively (N=28).

CONCLUSIONS

To our knowledge, this is the first review as to the extent to which existing guidance for designing and analysing randomised surgical trials covers the management of clustering, by centre or surgeon, and the surgical learning curve. Twice the number of identified documents targeted design aspects than analysis. Most notably, no single document exists for use when designing these studies, which may lead to inconsistencies in practice. The development of a single document, with agreed principles to guide trial design and analysis across a range of realistic clinical scenarios, is needed.

Silver-impregnated, antibiotic-impregnated or non-impregnated ventriculoperitoneal shunts to prevent shunt infection: the BASICS three-arm RCT

BACKGROUND

Insertion of a ventriculoperitoneal shunt to treat hydrocephalus is one of the most common neurosurgical procedures worldwide. Shunt infection affects up to 15% of patients, resulting in long hospital stays, multiple surgeries and reduced cognition and quality of life.

OBJECTIVES

The aim of this trial was to determine whether or not antibiotic-impregnated ventriculoperitoneal shunts (hereafter referred to as antibiotic shunts) (e.g. impregnated with rifampicin and clindamycin) or silver-impregnated ventriculoperitoneal shunts (hereafter referred to as silver shunts) reduce infection compared with standard ventriculoperitoneal shunts (hereafter referred to as standard shunts).

DESIGN

This was a three-arm, superiority, multicentre, parallel-group randomised controlled trial. Patients and a central primary outcome review panel, but not surgeons or operating staff, were blinded to the type of ventriculoperitoneal shunt inserted.

SETTING

The trial was set in 21 neurosurgical wards across the UK and the Republic of Ireland.

PARTICIPANTS

Participants were patients with hydrocephalus of any aetiology who were undergoing insertion of their first ventriculoperitoneal shunt.

INTERVENTIONS

Participants were allocated 1 : 1 : 1 by pressure-sealed envelope to receive a standard non-impregnated, silver-impregnated or antibiotic-impregnated ventriculoperitoneal shunt at the time of insertion. Ventriculoperitoneal shunts are medical devices, and were used in accordance with the manufacturer's instructions for their intended purpose.

MAIN OUTCOME MEASURES

The primary outcome was time to ventriculoperitoneal shunt failure due to infection. Secondary outcomes were time to failure for any cause, reason for failure (infection, mechanical), types of ventriculoperitoneal shunt infection, rate of infection after first clean (non-infected) revision and health economics. Outcomes were analysed by intention to treat.

RESULTS

Between 26 June 2013 and 9 October 2017, 1605 patients from neonate to 91 years of age were randomised to the trial: n = 36 to the standard shunt, n = 538 to the antibiotic shunt and n = 531 to the silver shunt. Patients who did not receive a ventriculoperitoneal shunt (n = 4) or who had an infection at the time of insertion (n = 7) were not assessed for the primary outcome. Infection occurred in 6.0% (n = 32/533) of those who received the standard shunt, in 2.2% (n = 12/535) of those who received the antibiotic shunt and in 5.9% (n = 31/526) of those who received the silver shunt. Compared with the standard shunt, antibiotic shunts were associated with a lower rate of infection (cause-specific hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80) and a decreased probability of infection (subdistribution hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80). Silver shunts were not associated with a lower rate of infection than standard shunts (cause-specific hazard ratio 0.99, 97.5% confidence interval 0.56 to 1.74). The ventriculoperitoneal shunt failure rate attributable to any cause was 25.0% overall and did not differ between arms. Antibiotic shunts save £135,753 per infection avoided. There were no serious adverse events.

LIMITATIONS

It was not possible to blind treating neurosurgeons to the ventriculoperitoneal shunt type. The return rate for patient-reported outcomes was low. Limitations to the economic evaluation included failure to obtain Hospital Episode Statistics data from NHS Digital, as per protocol. Reliance on patient-level information and costing systems data mitigated these limitations.

CONCLUSIONS

Antibiotic shunts have a reduced infection rate compared with standard shunts, whereas silver shunts do not. Antibiotic shunts are cost-saving.

FUTURE WORK

A sample collection has been established that will enable the study of surrogate markers of ventriculoperitoneal shunt infection in cerebrospinal fluid or blood using molecular techniques. A post hoc analysis to study factors related to shunt failure will be performed as part of a future study. An impact analysis to assess change in practice is planned.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN49474281.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 17. See the NIHR Journals Library website for further project information.

O77: DOES MESH IMPROVE PATIENT SATISFACTION AND HEALTH-RELATED QUALITY OF LIFE AFTER IMPLANT-BASED BREAST RECONSTRUCTION? A MULTICENTRE PROSPECTIVE COHORT STUDY

Introduction

Biological and synthetic meshes may improve outcomes of immediate IBBR by facilitating single-stage direct-to-implant procedures. However, high-quality supporting evidence is limited, particularly regarding PROs.

Method

2108 consecutive women undergoing IBBR at 81 centres were prospectively recruited between 2014-2016. Demographic, operative, oncological and 3-month complication data were collected. An 18-month questionnaire assessed PROs using the validated BREAST-Q and a five-point Likert scale rating of overall reconstructive outcome.

The impacts of different IBBR techniques on PROs were explored using mixed-effects regression models adjusted for clinically-relevant confounders and including a random effect to account for clustering by centre. The reference group was two- stage submuscular reconstruction without mesh.

Result

1470 participants consented to receive the questionnaire and 891 completed it. 67 patients underwent two-stage submuscular reconstruction; 764 patients received subpectoral reconstructions with biological mesh (n=495) synthetic mesh (n=95) or dermal sling (n=174). 14 patients underwent prepectoral reconstructions (introduced late in the study).

Compared with two-stage reconstructions, no differences in PROs were seen in biological or synthetic mesh-assisted or dermal sling procedures (p&gt;0.05). However, prepectoral IBBR patients reported better satisfaction with breasts (difference=6.63, 95% confidence interval[1.65–11.61], p=0.009). Outcomes were similar to those in the NMBRA 2008/9 cohort, which included submuscular procedures only.

Conclusion

This study does not suggest that mesh improves PROs of IBBR. It provides early data supporting improved satisfaction with breasts following prepectoral reconstructions. Future trials are needed to robustly evaluate prepectoral techniques.

Abbrev

IBBR: implant-based breast reconstruction, PRO: patient-reported outcome, NMBRA: National Mastectomy and Breast Reconstruction Audit

Take-home message

Although mesh-assisted techniques have become widely adopted, this large, prospective, multicentre cohort study does not suggest that mesh improves patient-reported outcomes of implant-based breast reconstruction compared with standard submuscular techniques. However, it provides early data to support improved satisfaction with breasts in the prepectoral setting, which now requires robust evaluation.

O58: THE IMPACT OF RADIOTHERAPY ON PATIENT-REPORTED OUTCOMES OF IMMEDIATE IMPLANT-BASED BREAST RECONSTRUCTION: RESULTS OF A PROSPECTIVE MULTICENTRE COHORT STUDY

Introduction

Post-mastectomy radiotherapy (PMRT) is increasing given to improve breast cancer outcomes but can increase complication rates following implant-based breast reconstruction (IBBR). Little, however, is known about the impact of PMRT on patient-reported outcomes (PROs) of IBBR, especially in the context of mesh-assisted techniques.

Method

2108 consecutive women undergoing IBBR at 81 UK centres were prospectively recruited between 2014 and 2016. Demographic, operative, oncological and 3-month complication data were collected, and patients who consented received post-operative questionnaires. An 18-month questionnaire assessed PROs using the validated BREAST-Q. The effect of IBBR on PROs was investigated using mixed-effects regression models adjusted for clinically relevant confounders and including a random effect to account for potential clustering by centre.

Result

1693 iBRA participants underwent mastectomy for malignancy, of whom 1187 (70%) consented to receive the 18-month questionnaire and 732 (43%) completed it. Patients undergoing PMRT (n=214) reported significantly worse scores across 3 BREAST-Q domains: satisfaction with breasts (-6.27 points, p=0.008, 95% confidence interval (CI)[-10.91,-1.63]), satisfaction with outcome (-7.53 points, p=0.002, CI[-12.20,-2.85]) and physical well-being (-6.55 points, p&lt;0.001, CI[-9.43,-3.67]). Overall satisfaction was worse in the PMRT group (OR 0.497, p=0.002, CI[0.32,0.77]). Use of biological mesh did not ameliorate the impact of PMRT on patient satisfaction (interaction term p-values [0.173 - 0.826]).

Conclusion:

PMRT adversely affects PROs of IBBR. This should be discussed with patients considering IBBR, especially if PMRT is anticipated or indications are borderline, to enable informed decisions regarding oncological and reconstructive options.

Abbrev

PMRT: post-mastectomy radiotherapy, PRO: patient-reported outcome

Take-home message

This multicentre, prospective cohort study of 732 patients undergoing implant-based breast reconstruction demonstrates worse 18-month patient-reported outcomes in women who received post-mastectomy radiotherapy than those who did not. These data should be discussed with patients to help them make informed decisions about reconstructive surgery.

Neurosurgical CSF Diversion in Idiopathic Intracranial Hypertension: A Narrative Review

The prevalence of idiopathic intracranial hypertension (IIH), a complex disorder, is increasing globally in association with obesity. The IIH syndrome occurs as the result of elevated intracranial pressure, which can cause permanent visual impairment and loss if not adequately managed. CSF diversion via ventriculoperitoneal and lumboperitoneal shunts is a well-established strategy to protect vision in medically refractory cases. Success of CSF diversion is compromised by high rates of complication; including over-drainage, obstruction, and infection. This review outlines currently used techniques and technologies in the management of IIH. Neurosurgical CSF diversion is a vital component of the multidisciplinary management of IIH.

Patient-reported outcomes of immediate implant-based breast reconstruction with and without biological or synthetic mesh

BACKGROUND

Biological and synthetic meshes may improve the outcomes of immediate implant-based breast reconstruction (IBBR) by facilitating single-stage procedures and improving cosmesis. Supporting evidence is, however, limited. The aim of this study was to explore the impact of biological and synthetic mesh on patient-reported outcomes (PROs) of IBBR 18 months after surgery.

METHODS

Consecutive women undergoing immediate IBBR between February 2014 and June 2016 were recruited to the study. Demographic, operative, oncological and 3-month complication data were collected, and patients received validated BREAST-Q questionnaires at 18 months. The impact of different IBBR techniques on PROs were explored using mixed-effects regression models adjusted for clinically relevant confounders, and including a random effect to account for clustering by centre.

RESULTS

A total of 1470 participants consented to receive the questionnaire and 891 completed it. Of these, 67 women underwent two-stage submuscular reconstructions. Some 764 patients had a submuscular reconstruction with biological mesh (495 women), synthetic mesh (95) or dermal sling (174). Fourteen patients had a prepectoral reconstruction. Compared with two-stage submuscular reconstructions, no significant differences in PROs were seen in biological or synthetic mesh-assisted or dermal sling procedures. However, patients undergoing prepectoral IBBR reported better satisfaction with breasts (adjusted mean difference +6.63, 95 per cent c.i. 1.65 to11.61; P = 0.009). PROs were similar to those in the National Mastectomy and Breast Reconstruction Audit 2008-2009 cohort, which included two-stage submuscular procedures only.

CONCLUSION

This study found no difference in PROs of subpectoral IBBR with or without biological or synthetic mesh, but provides early data to suggest improved satisfaction with breasts following prepectoral reconstruction. Robust evaluation is required before this approach can be adopted as standard practice.

Adding a fourth rater to three had little impact in pre-linguistic outcome classification

The consequence of differing levels of agreement across raters is rarely studied. Subsequently, knowledge is limited on how number of raters affects the outcome. The present study aimed to examine the impact on pre-linguistic outcome classifications of 12-month-old infants when using four raters compared to three. Thirty experienced Speech and Language Therapists (SLTs) from five countries assessed 20 minute video recordings of four 12-month-old infants during a play session with a parent. One recording was assessed twice. A naturalistic listening method in real time was used. This involved: (1) assessing, each syllable as canonical or non-canonical, and (2) following the recording, assessing if the infant was babbling canonically and listing the syllables the infant produced with command. The impact that four raters had on outcome, compared to three, was explored by classifying the outcome based on all possible combinations of three raters and determining the frequency that the outcome assessment changed when a fourth assessor was added. Results revealed that adding a fourth rater had a minimal impact on canonical babbling ratio assessment. Presence/absence of canonical babbling and size of consonant inventory showed a negligible impact on three out of four recordings, whereas the size of syllable inventory and presence/absence of canonical babbling was minimally affected in one recording by adding a fourth rater. In conclusion, adding a forth rater in assessment of pre-linguistic utterances in 12-month-old infants with naturalistic assessment in real time does not affect outcome classifications considerably. Thus, using three raters, as opposed to four, is recommended.

A randomised controlled trial comparing palate surgery at 6 months versus 12 months of age (the TOPS trial): a statistical analysis plan

Background

Cleft palate is among the most common birth abnormalities. The success of primary surgery in the early months of life is crucial for successful feeding, hearing, dental development, and facial growth. Over recent decades, age at palatal surgery in infancy has reduced. The Timing Of Primary Surgery for cleft palate (TOPS) trial aims to determine whether, in infants with cleft palate, it is better to perform primary surgery at age 6 or 12 months (corrected for gestational age).

Methods/design

The TOPS trial is an international, two-arm, parallel group, randomised controlled trial. The primary outcome is insufficient velopharyngeal function at 5 years of age. Secondary outcomes, measured at 12 months, 3 years, and 5 years of age, include measures of speech development, safety of the procedure, hearing level, middle ear function, dentofacial development, and growth. The analysis approaches for primary and secondary outcomes are described here, as are the descriptive statistics which will be reported. The TOPS protocol has been published previously.

Discussion

This paper provides details of the planned statistical analyses for the TOPS trial and will reduce the risk of outcome reporting bias and data-driven results.

Trial registration

ClinicalTrials.gov NCT00993551. Registered on 9 October 2009.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-020-04886-y.

Infant hydrocephalus: what valve first?

PURPOSE

To review the use of different valve types in infants with hydrocephalus, in doing so, determining whether an optimal valve choice exists for this patient cohort.

METHODS

We conducted (1) a literature review for all studies describing valve types used (programmable vs. non-programmable, valve size, pressure) in infants (≤ 2 years) with hydrocephalus, (2) a review of data from the pivotal BASICS trial for infant patients and (3) a separate, institutional cohort study from Alder Hey Children's Hospital NHS Foundation Trust. The primary outcome was any revision not due to infection.

RESULTS

The search identified 19 studies that were included in the review. Most did not identify a superior valve choice between programmable and non-programmable, small compared to ultra-small, and differential pressure compared to flow-regulating valves. Five studies investigated a single-valve type without a comparator group. The BASICS data identified 391 infants, with no statistically significant difference between gravitational and programmable subgroups. The institutional data from our tertiary referral centre did not reveal any significant difference in failure rate between valve subtypes.

CONCLUSION

Our review highlights the challenges of valve selection in infant hydrocephalus, reiterating that the concept of an optimal valve choice in this group remains a controversial one. While the infant-hydrocephalic population is at high risk of valve failure, heterogeneity and a lack of direct comparison between valves in the literature limit our ability to draw meaningful conclusions. Data that does exist suggests at present that there is no difference in non-infective failure rate are increasing in number, with the British valve subtypes in infant hydrocephalus, supported by both the randomised trial and institutional data in this study.

Managing clustering effects and learning effects in the design and analysis of multicentre randomised trials: a survey to establish current practice

Background

Patient outcomes can depend on the treating centre, or health professional, delivering the intervention. A health professional’s skill in delivery improves with experience, meaning that outcomes may be associated with learning. Considering differences in intervention delivery at trial design will ensure that any appropriate adjustments can be made during analysis. This work aimed to establish practice for the allowance of clustering and learning effects in the design and analysis of randomised multicentre trials.

Methods

A survey that drew upon quotes from existing guidelines, references to relevant publications and example trial scenarios was delivered. Registered UK Clinical Research Collaboration Registered Clinical Trials Units were invited to participate.

Results

Forty-four Units participated (N = 50). Clustering was managed through design by stratification, more commonly by centre than by treatment provider. Managing learning by design through defining a minimum expertise level for treatment provider was common (89%). One-third reported experience in expertise-based designs. The majority of Units had adjusted for clustering during analysis, although approaches varied. Analysis of learning was rarely performed for the main analysis (n = 1), although it was explored by other means. The insight behind the approaches used within and reasons for, or against, alternative approaches were provided.

Conclusions

Widespread awareness of challenges in designing and analysing multicentre trials is identified. Approaches used, and opinions on these, vary both across and within Units, indicating that approaches are dependent on the type of trial. Agreeing principles to guide trial design and analysis across a range of realistic clinical scenarios should be considered.

Antibiotic or silver versus standard ventriculoperitoneal shunts (BASICS): a multicentre, single-blinded, randomised trial and economic evaluation

BACKGROUND

Insertion of a ventriculoperitoneal shunt for hydrocephalus is one of the commonest neurosurgical procedures worldwide. Infection of the implanted shunt affects up to 15% of these patients, resulting in prolonged hospital treatment, multiple surgeries, and reduced cognition and quality of life. Our aim was to determine the clinical and cost-effectiveness of antibiotic (rifampicin and clindamycin) or silver shunts compared with standard shunts at reducing infection.

METHODS

In this parallel, multicentre, single-blind, randomised controlled trial, we included patients with hydrocephalus of any aetiology undergoing insertion of their first ventriculoperitoneal shunt irrespective of age at 21 regional adult and paediatric neurosurgery centres in the UK and Ireland. Patients were randomly assigned (1:1:1 in random permuted blocks of three or six) to receive standard shunts (standard shunt group), antibiotic-impregnated (0·15% clindamycin and 0·054% rifampicin; antibiotic shunt group), or silver-impregnated shunts (silver shunt group) through a randomisation sequence generated by an independent statistician. All patients and investigators who recorded and analysed the data were masked for group assignment, which was only disclosed to the neurosurgical staff at the time of operation. Participants receiving a shunt without evidence of infection at the time of insertion were followed up for at least 6 months and a maximum of 2 years. The primary outcome was time to shunt failure due the infection and was analysed with Fine and Gray survival regression models for competing risk by intention to treat. This trial is registered with ISRCTN 49474281.

FINDINGS

Between June 26, 2013, and Oct 9, 2017, we assessed 3505 patients, of whom 1605 aged up to 91 years were randomly assigned to receive either a standard shunt (n=536), an antibiotic-impregnated shunt (n=538), or a silver shunt (n=531). 1594 had a shunt inserted without evidence of infection at the time of insertion (533 in the standard shunt group, 535 in the antibiotic shunt group, and 526 in the silver shunt group) and were followed up for a median of 22 months (IQR 10-24; 53 withdrew from follow-up). 32 (6%) of 533 evaluable patients in the standard shunt group had a shunt revision for infection, compared with 12 (2%) of 535 evaluable patients in the antibiotic shunt group (cause-specific hazard ratio [csHR] 0·38, 97·5% CI 0·18-0·80, p=0·0038) and 31 (6%) of 526 patients in the silver shunt group (0·99, 0·56-1·74, p=0·96). 135 (25%) patients in the standard shunt group, 127 (23%) in the antibiotic shunt group, and 134 (36%) in the silver shunt group had adverse events, which were not life-threatening and were mostly related to valve or catheter function.

INTERPRETATION

The BASICS trial provides evidence to support the adoption of antibiotic shunts in UK patients who are having their first ventriculoperitoneal shunt insertion. This practice will benefit patients of all ages by reducing the risk and harm of shunt infection.

FUNDING

UK National Institute for Health Research Health Technology Assessment programme.

Timing Of Primary Surgery for cleft palate (TOPS): protocol for a randomised trial of palate surgery at 6 months versus 12 months of age

INTRODUCTION

Cleft palate is among the most common birth abnormalities. The success of primary surgery in the early months of life is crucial for successful feeding, speech, hearing, dental development and facial growth. Over recent decades, age at palatal surgery in infancy has reduced. This has led to palatal closure in one-stage procedures being carried out around the age of 12 months, but in some cases as early as 6 months. The primary objective of the Timing Of Primary Surgery for Cleft Palate (TOPS)trial is to determine whether surgery for cleft palate performed at 6 or 12 months of age is most beneficial for speech outcomes.

METHODS AND ANALYSIS

Infants with a diagnosis of non-syndromic isolated cleft palate will be randomised to receive standardised primary surgery (Sommerlad technique) for closure of the cleft at either 6 months or 12 months, corrected for gestational age. The primary outcome will be perceived insufficient velopharyngeal function at 5 years of age. Secondary outcomes measured across 12 months, 3 years and 5 years will include growth, safety of the procedure, dentofacial development, speech, hearing level and middle ear function. Video and audio recordings of speech will be collected in a standardised age-appropriate manner and analysed independently by multiple speech and language therapists. The trial aims to recruit and follow-up 300 participants per arm. Data will be analysed according to the intention-to-treat principle using a 5% significance level. All analyses will be prespecified within a full and detailed statistical analysis plan.

ETHICS AND DISSEMINATION

Ethical approval has been sought in each participating country according to country-specific procedures. Trial results will be presented at conferences, published in peer-reviewed journals and disseminated through relevant patient support groups.

TRIAL REGISTRATION NUMBER

NCT00993551; Pre-results.

Funders improved the management of learning and clustering effects through design and analysis of randomized trials involving surgery

OBJECTIVE

The objective of this study was to provide insight into current practice in planning for, and acknowledging, the presence of learning and clustering effects, by treating center and surgeon, when developing randomized surgical trials.

STUDY DESIGN AND SETTING

Complexities associated with delivering surgical interventions, such as clustering effects, by center or surgeon, and surgical learning should be considered at trial design. Main trial publications, within the wider literature, under-report these considerations. Funded applications, within a 4-year period, from a leading UK funding body were searched. Data were extracted on considerations for learning and clustering effects and the driver, funder, or applicant, behind these.

RESULTS

Fifty trials were eligible. Managing learning through establishing predefined center and surgeon credentials was common. One planned exploratory analysis of learning within center, and two within surgeon. Clustering, by site and surgeon, was often managed through stratifying randomization, with 81% and 60%, respectively, also planning to subsequently adjust analysis. One-third of responses to referees contained funder led changes accounting for learning and/or clustering.

CONCLUSION

This review indicates that researchers do consider impact of learning and clustering, by center and surgeon, during trial development. Furthermore, the funder is identified as a potential driver of considerations.

Short-term safety outcomes of mastectomy and immediate implant-based breast reconstruction with and without mesh (iBRA): a multicentre, prospective cohort study

BACKGROUND

Use of biological or synthetic mesh might improve outcomes of immediate implant-based breast reconstruction-breast reconstruction with implants or expanders at the time of mastectomy-but there is a lack of high-quality evidence to support the safety or effectiveness of the technique. We aimed to establish the short-term safety of immediate implant-based breast reconstruction performed with and without mesh, to inform the feasibility of undertaking a future randomised clinical trial comparing different breast reconstruction techniques.

METHODS

In this prospective, multicentre cohort study, we consecutively recruited women aged 16 years or older who had any type of immediate implant-based breast reconstruction for malignancy or risk reduction, with any technique, at 81 participating breast and plastic surgical units in the UK. Data about patient demographics and operative, oncological, and complication details were collected before and after surgery. Outcomes of interest were implant loss (defined as unplanned removal of the expander or implant), infection requiring treatment with antibiotics or surgery, unplanned return to theatre, and unplanned re-admission to hospital for complications of reconstructive surgery, up to 3 months after reconstruction and assessed by clinical review or patient self-report. Follow-up is complete. The study is registered with the ISRCTN Registry, number ISRCTN37664281.

FINDINGS

Between Feb 1, 2014, and June 30, 2016, 2108 patients had 2655 mastectomies with immediate implant-based breast reconstruction at 81 units across the UK. 1650 (78%) patients had planned single-stage reconstructions (including 12 patients who had a different technique per breast). 1376 (65%) patients had reconstruction with biological (1133 [54%]) or synthetic (243 [12%]) mesh, 181 (9%) had non-mesh submuscular or subfascial implants, 440 (21%) had dermal sling implants, 42 (2%) had pre-pectoral implants, and 79 (4%) had other or a combination of implants. 3-month outcome data were available for 2081 (99%) patients. Of these patients, 182 (9%, 95% CI 8-10) experienced implant loss, 372 (18%, 16-20) required re-admission to hospital, and 370 (18%, 16-20) required return to theatre for complications within 3 months of their initial surgery. 522 (25%, 95% CI 23-27) patients required treatment for an infection. The rates of all of these complications are higher than those in the National Quality Standards (<5% for re-operation, re-admission, and implant loss, and <10% for infection).

INTERPRETATION

Complications after immediate implant-based breast reconstruction are higher than recommended by national standards. A randomised clinical trial is needed to establish the optimal approach to immediate implant-based breast reconstruction.

FUNDING

National Institute for Health Research, Association of Breast Surgery, and British Association of Plastic, Reconstructive and Aesthetic Surgeons.

Nerve root block versus surgery (NERVES) for the treatment of radicular pain secondary to a prolapsed intervertebral disc herniation: study protocol for a multi-centre randomised controlled trial

Background

Sciatica is a common condition reported to affect over 3% of the UK population at any time and is often caused by a prolapsed intervertebral disc (PID). Although the duration and severity of symptoms can vary, pain persisting beyond 6 weeks is unlikely to recover spontaneously and may require investigation and treatment. Currently, there is no specific care pathway for sciatica in the National Health Service (NHS), and no direct comparison exists between surgical microdiscectomy and transforaminal epidural steroid injection (TFESI). The NERVES (NErve Root block VErsus Surgery) trial aims to address this by comparing clinical and cost-effectiveness of surgical microdiscectomy and TFESI to treat sciatica secondary to a PID.

Methods/design

A total of 163 patients were recruited from NHS out-patient clinics across the UK and randomised to either microdiscectomy or TFESI. Adult patients (aged 16–65 years) with sciatic pain endured for between 6 weeks and 12 months are eligible if their symptoms have not been improved by at least one form of conservative (non-operative) treatment and they are willing to provide consent. Patients will be excluded if they present with neurological deficit or have had previous surgery at the same level. The primary outcome is patient-reported disability measured using the Oswestry Disability Questionnaire (ODQ) score at 18 weeks post randomisation and secondary outcomes include disability and pain scales using numerical pain ratings, modified Roland-Morris and Core Outcome Measures Index at 12-weekly intervals, and patient satisfaction at 54 weeks. Cost-effectiveness and quality of life (QOL) will be assessed using the EQ-5D-5 L and self-report cost data at 12-weekly intervals and Hospital Episode Statistics (HES) data. Adverse event data will be collected. Analysis will follow the principle of intention-to-treat.

Discussion

NERVES is the first trial to evaluate the comparative clinical and cost-effectiveness of microdiscectomy to local anaesthetic and steroid administered via TFESI. The results of this research may facilitate the development of an evidence-based treatment strategy for patients with sciatica.

Trial registration

ISRCTN, ID: ISRCTN04820368. Registered on 5 June 2014.

EudraCT EudraCT2014–002751-25. Registered on 8 October 2014.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2677-5) contains supplementary material, which is available to authorized users.

Adherence to best practice consensus guidelines for implant-based breast reconstruction: Results from the iBRA national practice questionnaire survey

INTRODUCTION

The 2008 National Mastectomy and Breast Reconstruction Audit demonstrated marked variation in the practice and outcomes of breast reconstruction in the UK. To standardise practice and improve outcomes for patients, the British professional associations developed best-practice guidelines with specific guidance for newer mesh-assisted implant-based techniques. We explored the degree of uptake of best-practice guidelines within units performing implant-based reconstruction (IBBR) as the first phase of the implant Breast Reconstruction Evaluation (iBRA) study.

METHODS

A questionnaire developed by the iBRA Steering Group was completed by trainee and consultant leads at breast and plastic surgical units across the UK. Simple summary statistics were calculated for each survey item to assess compliance with current best-practice guidelines.

RESULTS

81 units from 79 NHS Trusts completed the questionnaire. Marked variation was observed in adherence to guidelines, especially those relating to clinical governance and infection prevention strategies. Less than half (n = 28, 47%) of units obtained local clinical governance board approval prior to offering new mesh-based techniques and prospective audit of the clinical, cosmetic and patient-reported outcomes of surgery was infrequent. Most units screened for methicillin-resistant staphylococcus aureus prior to surgery but fewer than 1 in 3 screened for methicillin-sensitive strains. Laminar-flow theatres (recommended for IBBR) were not widely-available with less than 1 in 5 units having regular access. Peri-operative antibiotics were widely-used, but the type and duration were highly-variable.

CONCLUSIONS

The iBRA national practice questionnaire has demonstrated variation in reported practice and adherence to IBBR guidelines. High-quality evidence is urgently required to inform best practice.

A cohort examination to establish reporting of the remit and function of Trial Steering Committees in randomised controlled trials

Background

The DAMOCLES project established a widely used Data Monitoring Committee (DMC) Charter for randomised controlled trials (RCTs). Typically, within the UK, the DMC is advisory and recommends to another executive body; the Trial Steering Committee (TSC). Despite the executive role of the TSC, the CONSORT Statement does not explicitly require reporting of TSC activity, although is included as an example of good reporting. A lack of guidance on TSC reporting can impact transparency of trial oversight, ultimately leading to a misunderstanding regarding role and, subsequently, further variation in practice. This review aimed to establish reporting practice of TSC involvement in RCTs, and thus make recommendations for reporting.

Methods

A cohort examination identifying reporting practice was undertaken. The cohort comprised RCTs published in three leading medical journals (the British Medical Journal, The Lancet and the New England Journal of Medicine) within 6 months in 2012 and the full NIHR HTA Monograph series. Details of TSC constitution and impact were extracted from main publications and published supplements.

Results

Of 415 publications, 264 were eligible. These were typical in terms of trial design. Variations in reporting between journals and monographs was notable. TSC presence was identified in approximately half of trials (n = 144), of which 109 worked alongside a DMC. No publications justified not convening a TSC. When reported, the role of the committee and examples of impact in design, conduct and analysis were summarised.

Conclusions

We present the first review of reporting TSC activity in the published academic literature. An absence of reporting standards with regards to TSC constitution, activity and impact on trial conduct was identified which can influence transparency of reporting trial oversight. Consistent reporting is vital for the benefits and impact of the TSC role to be understood to support adoption of this oversight structure and reduce global variations in practice.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2300-1) contains supplementary material, which is available to authorized users.

The iBRA (implant breast reconstruction evaluation) study: protocol for a prospective multi-centre cohort study to inform the feasibility, design and conduct of a pragmatic randomised clinical trial comparing new techniques of implant-based breast reconstruction

BACKGROUND

Implant-based breast reconstruction (IBBR) is the most commonly performed reconstructive procedure in the UK. The introduction of techniques to augment the subpectoral pocket has revolutionised the procedure, but there is a lack of high-quality outcome data to describe the safety or effectiveness of these techniques. Randomised controlled trials (RCTs) are the best way of comparing treatments, but surgical RCTs are challenging. The iBRA (implant breast reconstruction evaluation) study aims to determine the feasibility, design and conduct of a pragmatic RCT to examine the effectiveness of approaches to IBBR.

METHODS/DESIGN

The iBRA study is a trainee-led research collaborative project with four phases:Phase 1 - a national practice questionnaire (NPQ) to survey current practicePhase 2 - a multi-centre prospective cohort study of patients undergoing IBBR to evaluate the clinical and patient-reported outcomesPhase 3- an IBBR-RCT acceptability survey and qualitative work to explore patients' and surgeons' views of proposed trial designs and candidate outcomes.Phase 4 - phases 1 to 3 will inform the design and conduct of the future RCT All centres offering IBBR will be encouraged to participate by the breast and plastic surgical professional associations (Association of Breast Surgery and British Association of Plastic Reconstructive and Aesthetic Surgeons). Data collected will inform the feasibility of undertaking an RCT by defining current practice and exploring issues surrounding recruitment, selection of comparator arms, choice of primary outcome, sample size, selection criteria, trial conduct, methods of data collection and feasibility of using the trainee collaborative model to recruit patients and collect data.

DISCUSSION

The preliminary work undertaken within the iBRA study will determine the feasibility, design and conduct of a definitive RCT in IBBR. It will work with the trainee collaborative to build capacity by creating an infrastructure of research-active breast and plastic surgeons which will facilitate future high-quality research that will ultimately improve outcomes for all women seeking reconstructive surgery.

TRIAL REGISTRATION

ISRCTN37664281.

A Randomised Controlled Trial of Treatment for Post-Stroke Homonymous Hemianopia: Screening and Recruitment

The authors report the screening process and recruitment figures for the VISION (Visual Impairment in Stroke; Intervention Or Not) trial. This is a prospective, randomised, single-blinded, three-arm controlled trial in 14 UK acute hospital stroke units. Stroke teams identified stroke survivors suspected as having homonymous hemianopia. Interventions included Fresnel prisms versus visual search training versus standard care (information only). Primary outcome was change in visual field assessment from baseline to 26 weeks. Secondary measures included change in quality-of-life questionnaires. Recruitment opened in May 2011. A total of 1171 patients were screened by the local principal investigators. Of 1171 patients, 178 (15.2%) were eligible for recruitment: 87 patients (7.4%) provided consent and were recruited; 91 patients (7.8%) did not provide consent, and 993 of 1171 patients (84.8%) failed to meet the eligibility criteria. Almost half were excluded due to complete/partial recovery of hemianopia (43.6%; n = 511). The most common ineligibility reason was recovery of hemianopia. When designing future trials in this area, changes in eligibility criteria/outcome selection to allow more patients to be recruited should be considered, e.g., less stringent levels of visual acuity/refractive error. Alternative outcomes measurable in the home environment, rather than requiring hospital attendance for follow-up, could facilitate increased recruitment.

Exploring the role and function of trial steering committees: results of an expert panel meeting

BACKGROUND

The independent oversight of clinical trials, which is recommended by the Medical Research Council (MRC) Guidelines for Good Clinical Practice, is typically provided by an independent advisory Data Monitoring Committee (DMC) and an independent executive committee, to whom the DMC makes recommendations. The detailed roles and function of this executive committee, known as the Trial Steering Committee (TSC), have not previously been studied or reviewed since those originally proposed by the MRC in 1998.

METHODS

An expert panel (n = 7) was convened comprising statisticians, clinicians and trial methodologists with prior TSC experience. Twelve questions about the role and responsibilities of the TSC were discussed by the panel at two full-day meetings. Each meeting was transcribed in full and the discussions were summarised.

RESULTS

The expert panel reached agreement on the role of the TSC, to which it was accountable, the membership, the definition of independence, and the experience and training needed. The management of ethical issues, difficult/complex situations and issues the TSC should not ask the DMC to make recommendations on were more difficult to discuss without specific examples, but support existed for further work to help share issues and to provide appropriate training for TSC members. Additional topics discussed, which had not been identified by previous work relating to the DMCs but were pertinent to the role of the TSC, included the following: review of data sharing requests, indemnity, lifespan of the TSC, general TSC administration, and the roles of both the Funder and the Sponsor.

CONCLUSIONS

This paper presents recommendations that will contribute to the revision and update of the MRC TSC terms of reference. Uncertainty remains in some areas due to the absence of real-life examples; future guidance on these issues would benefit from a repository of case studies. Notably, the role of a patient and public involvement (PPI) contributor was not discussed, and further work is warranted to explore the role of a PPI contributor in independent trial oversight.

Trial Steering Committees in randomised controlled trials: A survey of registered clinical trials units to establish current practice and experiences

BACKGROUND

The Medical Research Council Guidelines for Good Clinical Practice outlines a three-committee trial oversight structure--the day-to-day Trial Management Group, the Data Monitoring Committee and the Trial Steering Committee. In this model, the Trial Steering Committee is the executive committee that oversees the trial and considers the recommendations from the Data Monitoring Committee. There is yet to be in-depth consideration establishing the Trial Steering Committee's role and functionality.

METHODS

A survey to establish Trial Steering Committee's current practices, role and the use and opinion on the Medical Research Council guidelines was undertaken within UK Clinical Research Collaborative registered Clinical Trials Units.

RESULTS

Completed surveys were obtained from 38 of 47 fully and partially registered Units. Individual items in the survey were analysed and reported spanning current Trial Steering Committee practices including its role, requirement and experience required for membership; methods to identify members; and meeting frequency. Terms (a document describing the committee's remit, objectives and functionality) were obtained and analysed from 21 of 33 Units with documents in place at their Unit. A total of 20 responders suggested aspects of the current Medical Research Council Guidelines that need improvement.

CONCLUSION

We present the first survey reporting on practices within UK Clinical Research Collaborative registered Clinical Trials Units on the experience and remits of Trial Steering Committees. We have identified a widespread adoption of Medical Research Council Guidelines for Trial Steering Committees in the United Kingdom, but limitations in this existing provision have been identified that need to be addressed.

A pilot randomised controlled trial to assess the utility of an e-learning package that trains users in adverse drug reaction causality

Objectives

Causality assessment of adverse drug reactions (ADRs) by healthcare professionals is often informal which can lead to inconsistencies in practice. The Liverpool Causality Assessment Tool (LCAT) offers a systematic approach. An interactive, web‐based, e‐learning package, the Liverpool ADR Causality Assessment e‐learning Package (LACAeP), was designed to improve causality assessment using the LCAT. This study aimed to (1) get feedback on usability and usefulness on the LACAeP, identify areas for improvement and development, and generate data on effect size to inform a larger scale study; and (2) test the usability and usefulness of the LCAT.

Methods

A pilot, single‐blind, parallel‐group, randomised controlled trial hosted by the University of Liverpool was undertaken. Participants were paediatric medical trainees at specialty training level 1+ within the Mersey and North‐West England Deaneries. Participants were randomised (1 : 1) access to the LACAeP or no training. The primary efficacy outcome was score by correct classification, predefined by a multidisciplinary panel of experts. Following participation, feedback on both the LCAT and the LACAeP was obtained, via a built in survey, from participants.

Key findings

Of 57 randomised, 35 completed the study. Feedback was mainly positive although areas for improvement were identified. Seventy‐four per cent of participants found the LCAT easy to use and 78% found the LACAeP training useful. Sixty‐one per cent would be unlikely to recommend the training. Scores ranged from 4 to 13 out of 20. The LACAeP increased scores by 1.3, but this was not significant.

Conclusions

Improving the LACAeP before testing it in an appropriately powered trial, informed by the differences observed, is required. Rigorous evaluation will enable a quality resource that will be of value in healthcare professional training.

A randomised controlled trial to compare the clinical and cost-effectiveness of prism glasses, visual search training and standard care in patients with hemianopia following stroke: a protocol

INTRODUCTION

Homonymous hemianopia is a common and disabling visual problem after stroke. Currently, prism glasses and visual scanning training are proposed to improve it. The aim of this trial is to determine the effectiveness of these interventions compared to standard care.

METHODS AND ANALYSIS

The trial will be a multicentre three arm individually randomised controlled trial with independent assessment at 6 week, 12 week and 26 week post-randomisation. Recruitment will occur in hospital, outpatient and primary care settings in UK hospital trusts. A total of 105 patients with homonymous hemianopia and without ocular motility impairment, visual inattention or pre-existent visual field impairment will be randomised to one of three balanced groups. Randomisation lists will be stratified by site and hemianopia level (partial or complete) and created using simple block randomisation by an independent statistician. Allocations will be disclosed to patients by the treating clinician, maintaining blinding for outcome assessment. The primary outcome will be change in visual field assessment from baseline to 26 weeks. Secondary measures will include the Rivermead Mobility Index, Visual Function Questionnaire 25/10, Nottingham Extended Activities of Daily Living, Euro Qual-5D and Short Form-12 questionnaires. Analysis will be by intention to treat.

ETHICS AND DISSEMINATION

This study has been developed and supported by the UK Stroke Research Network Clinical Studies Group working with service users. Multicentre ethical approval was obtained through the North West 6 Research ethics committee (Reference 10/H1003/119). The trial is funded by the UK Stroke Association. Trial Registration: Current Controlled Trials ISRCTN05956042. Dissemination will consider usual scholarly options of conference presentation and journal publication in addition to patient and public dissemination with lay summaries and articles.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN05956042.

ADRIC: Adverse Drug Reactions In Children – a programme of research using mixed methods

Aims

To comprehensively investigate the incidence, nature and risk factors of adverse drug reactions (ADRs) in a hospital-based population of children, with rigorous assessment of causality, severity and avoidability, and to assess the consequent impact on children and families. We aimed to improve the assessment of ADRs by development of new tools to assess causality and avoidability, and to minimise the impact on families by developing better strategies for communication.

Review methods

Two prospective observational studies, each over 1 year, were conducted to assess ADRs in children associated with admission to hospital, and those occurring in children who were in hospital for longer than 48 hours. We conducted a comprehensive systematic review of ADRs in children. We used the findings from these studies to develop and validate tools to assess causality and avoidability of ADRs, and conducted interviews with parents and children who had experienced ADRs, using these findings to develop a leaflet for parents to inform a communication strategy about ADRs.

Results

The estimated incidence of ADRs detected in children on admission to hospital was 2.9% [95% confidence interval (CI) 2.5% to 3.3%]. Of the reactions, 22.1% (95% CI 17% to 28%) were either definitely or possibly avoidable. Prescriptions originating in the community accounted for 44 out of 249 (17.7%) of ADRs, the remainder originating from hospital. A total of 120 out of 249 (48.2%) reactions resulted from treatment for malignancies. Off-label and/or unlicensed (OLUL) medicines were more likely to be implicated in an ADR than authorised medicines [relative risk (RR) 1.67, 95% CI 1.38 to 2.02;p < 0.001]. When medicines used for the treatment of oncology patients were excluded, OLUL medicines were not more likely to be implicated in an ADR than authorised medicines (RR 1.03, 95% CI 0.72 to 1.48;p = 0.830). For children who had been in hospital for > 48 hours, the overall incidence of definite and probable ADRs based on all admissions was 15.9% (95% CI 15.0 to 16.8). Opiate analgesic drugs and drugs used in general anaesthesia (GA) accounted for > 50% of all drugs implicated in ADRs. The odds ratio of an OLUL drug being implicated in an ADR compared with an authorised drug was 2.25 (95% CI 1.95 to 2.59;p < 0.001). Risk factors identified were exposure to a GA, age, oncology treatment and number of medicines. The systematic review estimated that the incidence rates for ADRs causing hospital admission ranged from 0.4% to 10.3% of all children [pooled estimate of 2.9% (95% CI 2.6% to 3.1%)] and from 0.6% to 16.8% of all children exposed to a drug during hospital stay. New tools to assess causality and avoidability of ADRs have been developed and validated. Many parents described being dissatisfied with clinician communication about ADRs, whereas parents of children with cancer emphasised confidence in clinician management of ADRs and the way clinicians communicated about medicines. The accounts of children and young people largely reflected parents’ accounts. Clinicians described using all of the features of communication that parents wanted to see, but made active decisions about when and what to communicate to families about suspected ADRs, which meant that communication may not always match families’ needs and expectations. We developed a leaflet to assist clinicians in communicating ADRs to parents.

Conclusion

The Adverse Drug Reactions In Children (ADRIC) programme has provided the most comprehensive assessment, to date, of the size and nature of ADRs in children presenting to, and cared for in, hospital, and the outputs that have resulted will improve the management and understanding of ADRs in children and adults within the NHS. Recommendations for future research: assess the values that parents and children place on the use of different medicines and the risks that they will find acceptable within these contexts; focusing on high-risk drugs identified in ADRIC, determine the optimum drug dose for children through the development of a gold standard practice for the extrapolation of adult drug doses, alongside targeted pharmacokinetic/pharmacodynamic studies; assess the research and clinical applications of the Liverpool Causality Assessment Tool and the Liverpool Avoidability Assessment Tool; evaluate, in more detail, morbidities associated with anaesthesia and surgery in children, including follow-up in the community and in the home setting and an assessment of the most appropriate treatment regimens to prevent pain, vomiting and other postoperative complications; further evaluate strategies for communication with families, children and young people about ADRs; and quantify ADRs in other settings, for example critical care and neonatology.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Adverse drug reactions and off-label and unlicensed medicines in children: a nested case-control study of inpatients in a pediatric hospital

BACKGROUND

Off-label and unlicensed (OLUL) prescribing has been prevalent in pediatric practice. Using data from a prospective cohort study of adverse drug reactions (ADRs) among pediatric inpatients, we aimed to test the hypothesis that OLUL status is a risk factor for ADRs.

METHODS

A nested case?control study was conducted within a prospective cohort study. Details of all medicines administered were recorded, including information about OLUL status. The odds ratio for OLUL medicines being implicated in a probable or definite ADR was calculated. A multivariate Cox proportional hazards regression model was fitted to the data to assess the influence that OLUL medicine use had on the hazard of an ADR occurring.

RESULTS

A total of 10,699 medicine courses were administered to 1,388 patients. The odds ratio (OR) of an OLUL medicine being implicated in an ADR compared with an authorized medicine was 2.25 (95% confidence interval (CI) 1.95 to 2.59). Medicines licensed in children but given to a child below the minimum age or weight had the greatest odds of being implicated in an ADR (19% of courses in this category were implicated, OR 3.54 (95% CI 2.82 to 4.44). Each additional OLUL medicine given significantly increased the hazard of an ADR (hazard ratio (HR) 1.3 95% CI 1.2 to 1.3, P <0.001). Each additional authorized medicine given also significantly increased the hazard (HR 1.2 95% CI 1.2 to 1.3, P <0.001).

CONCLUSIONS

OLUL medicines are more likely to be implicated in an ADR than authorized medicines. The number of medicines administered is a risk factor for ADRs highlighting the need to use the lowest number of medicines, at the lowest dose for the shortest period, with continual vigilance by prescribers, in order to reduce the risk of ADRs.

Incidence, characteristics and risk factors of adverse drug reactions in hospitalized children - a prospective observational cohort study of 6,601 admissions

BACKGROUND

Adverse drug reactions (ADRs) are an important cause of harm in children. Current data are incomplete due to methodological differences between studies: only half of all studies provide drug data, incidence rates vary (0.6% to 16.8%) and very few studies provide data on causality, severity and risk factors of pediatric ADRs. We aimed to determine the incidence of ADRs in hospitalized children, to characterize these ADRs in terms of type, drug etiology, causality and severity and to identify risk factors.

METHODS

We undertook a year-long, prospective observational cohort study of admissions to a single UK pediatric medical and surgical secondary and tertiary referral center (Alder Hey, Liverpool, UK). Children between 0 and 16 years 11 months old and admitted for more than 48 hours were included. Observed outcomes were occurrence of ADR and time to first ADR for the risk factor analysis.

RESULTS

A total of 5,118 children (6,601 admissions) were included, 17.7% of whom experienced at least one ADR. Opiate analgesics and drugs used in general anesthesia (GA) accounted for more than 50% of all drugs implicated in ADRs. Of these ADRs, 0.9% caused permanent harm or required admission to a higher level of care. Children who underwent GA were at more than six times the risk of developing an ADR than children without a GA (hazard ratio (HR) 6.40; 95% confidence interval (CI) 5.30 to 7.70). Other factors increasing the risk of an ADR were increasing age (HR 1.06 for each year; 95% CI 1.04 to 1.07), increasing number of drugs (HR 1.25 for each additional drug; 95% CI 1.22 to 1.28) and oncological treatment (HR 1.90; 95% CI 1.40 to 2.60).

CONCLUSIONS

ADRs are common in hospitalized children and children who had undergone a GA had more than six times the risk of developing an ADR. GA agents and opiate analgesics are a significant cause of ADRs and have been underrepresented in previous studies. This is a concern in view of the increasing number of pediatric short-stay surgeries.

Enhancement of sphingosine kinase 1 catalytic activity by deletion of 21 amino acids from the COOH-terminus

Sphingosine kinase 1 (SphK1) responds to a variety of growth factor signals by increasing catalytic activity as it translocates to the plasma membrane (PM). Several studies have identified amino acids residues involved in translocation yet how SphK1 increases its catalytic activity remains to be elucidated. Herein, we report that deletion of 21 amino acids from the COOH-terminus of SphK1 (1-363) results in increased catalytic activity relative to wild-type SphK1 (1-384) which is independent of the phosphorylation state of Serine 225 and PMA stimulation. Importantly, HEK293 cells stably expressing the 1-363 protein exhibit enhanced cell growth under serum-deprived cell culture conditions. Together the evidence indicates that the COOH-terminal region of SphK1 encompasses a structural element that is necessary for the increase in catalytic activity in response to PMA treatment and that its deletion renders SphK1 constitutively active with respect to PMA treatment.

Sphingosine kinase 1 localized to the plasma membrane lipid raft microdomain overcomes serum deprivation induced growth inhibition

Several studies have demonstrated that sphingosine kinase 1 (SphK1) translocates to the plasma membrane (PM) upon its activation and further suggested the plasma membrane lipid raft microdomain (PMLRM) as a target for SphK1 relocalization. To date, however, direct evidence of SphK1 localization to the PMLRM has been lacking. In this report, using multiple biochemical and subcellular fractionation techniques we demonstrate that endogenous SphK1 protein and its substrate, D-erythro-sphingosine, are present within the PMLRM. Additionally, we demonstrate that the PMA stimulation of SphK1 localized to the PMLRM results in production of sphingosine-1-phosphate as well as induction of cell growth under serum deprivation conditions. We further report that Ser225Ala and Thr54Cys mutations, reported to abrogate phosphatidylserine binding, block SphK1 targeting to the PMLRM and SphK1 induced cell growth. Together these findings provide direct evidence that the PMLRM is the major site of action for SphK1 to overcome serum-deprived cell growth inhibition.

Sphingosine kinase 1 protein and mRNA are overexpressed in non-Hodgkin lymphomas and are attractive targets for novel pharmacological interventions

Sphingosine kinase 1 (SphK1) is an oncoprotein capable of directly transforming cells and is associated with resistance to chemotherapy and radiotherapy. SphK1 is increased in various human cancers; whereas, blockade restores sensitivity to therapeutic killing in chemotherapy resistant cancer cell lines. We investigated SphK1 expression in clinical tissue samples from patients with non-Hodgkin lymphomas (NHL). Tissues from 69 patients with either NHL (n = 44) or reactive lymphoid hyperplasias (RH) (n = 25) were examined for expression of SphK1 protein by Western blot and immunohistochemistry (IHC), and SphK1 and SphK2 mRNA by quantitative real-time reverse transcriptase polymerase chain reaction. SphK1 protein (p = 0.008) and mRNA (p = 0.035) levels were higher in NHL than RH, with a clear trend toward increasing levels with increasing clinical grade (p = 0.005 for SphK1 protein, p = 0.035 for IHC score and p = 0.002 for SphK1 mRNA). IHC generally confirmed protein signal in neoplastic cells, but some lymphomas exhibited staining in non-neoplastic cells. SphK1 is overexpressed in NHL and increases with increasing clinical grade. These results, combined with prior mechanistic studies suggest that SphK1 is an attractive novel target for pharmacological interventions for NHL.

Sphingosine kinase 1 expression is regulated by signaling through PI3K, AKT2, and mTOR in human coronary artery smooth muscle cells

Sphingosine kinase 1 (SphK1) is a lipid kinase implicated in mitogenic signaling pathways in vascular smooth muscle cells. We demonstrate that human coronary artery smooth muscle (HCASM) cells require SphK1 for growth and that SphK1 mRNA and protein levels are elevated in PDGF stimulated HCASM cells. To determine the mechanism of PDGF-induced SphK1 expression, we used pharmacological inhibitors of the PI3K/AKT/mTOR signaling pathway. Wortmannin, SH-5, and rapamycin significantly blocked PDGF-stimulated induction of SphK1 mRNA and protein expression, indicating a regulatory role of the PI3K/AKT/mTOR pathway in SphK1 expression. To determine which isoform of AKT regulates SphK1 mRNA and protein levels, siRNAs specific for AKT1, AKT2, and AKT3 were used. We show that AKT2 siRNA significantly blocked PDGF-stimulated increases in SphK1 mRNA and protein expression levels as well as SphK1 enzymatic activity levels. In contrast, AKT1 or AKT3 siRNA did not have an effect. Together, these results demonstrate that the PI3K/AKT/mTOR signaling pathway is involved in regulation of SphK1, with AKT2 playing a key role in PDGF-induced SphK1 expression in HCASM cells.