5-year mental health outcomes for children and adolescents presenting with psychiatric symptoms to general practitioners in England: a retrospective cohort study

BACKGROUND

Little information is available on the clinical trajectories of children and adolescents who attend general practice (GP) with psychiatric symptoms. We aimed to examine 5-year service use in English primary care for children and adolescents with neurodevelopmental or mental health symptoms or diagnoses.

METHODS

In this retrospective cohort study, we used anonymised primary care health records from the Clinical Practice Research Datalink Aurum database (CPRD-Aurum). We identified children and adolescents (aged 3-18 years) presenting to primary care in England between Jan 1, 2000, and May 9, 2016, with a symptom or diagnosis of a mental health, behavioural, or neurodevelopmental condition. Participants were excluded if they had less than 1 year of follow-up. We followed up participants from their index date until either death, transfer out of the practice, or the end of data collection on May 5, 2021, and for trajectory analysis we limited follow-up to 5 years. We used group-based multi-trajectory models to identify clusters with similar trajectories over 5 years of follow-up for three primary outcomes: mental health-related GP contacts, psychotropic medication prescriptions, and specialist mental health-care contact. We did survival analysis to examine the associations between trajectory-group membership and hospital admission for self-harm or death by suicide, as indicators of severe psychiatric distress.

FINDINGS

We included 369 340 children and adolescents, of whom 180 863 (49·0%) were girls, 188 438 (51·0%) were boys, 39 (<0·1%) were of indeterminate gender, 290 125 (78·6%) were White, 9161 (2·5%) were South Asian, 10 418 (2·8%) were Black, 8115 (2·2%) were of mixed ethnicity, and 8587 (2·3%) were other ethnicities, and the median age at index presentation was 13·6 years (IQR 8·4-16·7). In the best-fitting, seven-group, group-based multi-trajectory model, over a 5-year period, the largest group (low contact; 207 985 [51·2%]) had low rates of additional service contact or psychotropic prescriptions. The other trajectory groups were moderate, non-pharmacological contact (43 836 [13·0%]); declining contact (25 469 [8·7%]); year-4 escalating contact (18 277 [6·9%]); year-5 escalating contact (18 139; 5·2%); prolonged GP contact (32 147 [8·6%]); and prolonged specialist contact (23 487 [6·5%]). Non-White ethnicity and presentation in earlier study years (eg, 2000-2004) were associated with low-contact group membership. The prolonged specialist-contact group had the highest risk of hospital admission for self-harm (hazard ratio vs low-contact group 2·19 [95% CI 2·03-2·36]) and suicide (2·67 [1·72-4·14]).

INTERPRETATION

Most children and adolescents presenting to primary care with psychiatric symptoms or diagnoses have low or declining rates of ongoing contact. If these trajectories reflect symptomatic improvement, these findings provide reassurance for children and adolescents and their caregivers. However, these trajectories might reflect an unmet need for some children and adolescents.

FUNDING

National Institute for Health and Care Research and the Wellcome Trust.

Changes to healthcare utilisation and symptoms for common mental health problems over the first 21 months of the COVID-19 pandemic: parallel analyses of electronic health records and survey data in England

Background

Few studies have investigated the effect of the COVID-19 pandemic on mental health beyond 2020. This study quantifies changes to healthcare utilisation and symptoms for common mental health problems over the pandemic's first 21 months.

Methods

Parallel cohort studies using primary care database and survey data for adults (≥16 years) in England from January 2015 to December 2021: 16,551,842 from the Clinical Practice Research Datalink (CPRD) and 40,699 from the UK Household Longitudinal Survey (UKHLS). Interrupted time-series models estimated changes in monthly prevalence of presentations and prescribed medications for anxiety and depression (CPRD); and self-reported psychological distress (UKHLS). The pandemic period was divided into five phases: 1st Wave (April-May 2020); post-1st Wave (June-September 2020); 2nd Wave (October 2020-February 2021); post 2nd Wave (March-May 2021); 3rd Wave (June-December 2021).

Findings

Primary care presentations for depression or anxiety dropped during the first wave (4.6 fewer monthly appointments per 1000 patients, 4.4-4.8) and remained lower than expected throughout follow-up. Self-reported psychological distress exceeded expected levels during the first (Prevalence Ratio = 1.378, 95% CI 1.289-1.459) and second waves (PR = 1.285, 1.189-1.377), returning towards expected levels during the third wave (PR = 1.038, 0.929-1.154). Increases in psychological distress and declines in presentations were greater for women. The decrease in primary care presentations for depression and anxiety exceeded that for physical health conditions (rheumatoid arthritis, diabetes, urinary tract infections). Anxiety and depression prescriptions returned to pre-pandemic levels during the second wave due to increased repeat prescriptions.

Interpretation

Despite periods of distress during the pandemic, we did not find an enduring effect on common mental health problems. The fall in primary care presentations for anxiety or depression suggests changing healthcare utilisation for mental distress and a potential treatment gap.

Funding

National Institute for Health and Care Research (NIHR).

Trends in antipsychotic prescribing to children and adolescents in England: cohort study using 2000-19 primary care data

BACKGROUND

The prescription of antipsychotics to children and adolescents has been increasing worldwide. We described up-to-date trends in antipsychotic prescribing and identified likely indications in a contemporary English cohort.

METHODS

We used a large primary care database, the Clinical Practice Research Datalink (CPRD) Aurum database, and we included all children and adolescents aged 3-18 years in the database and registered in England between Jan 1, 2000, and Dec 31, 2019, excluding those whose gender was recorded as indeterminate. Participants were followed up until the earliest of Dec 31, 2019, June 30 of the year they turned 18 years, their death, when they transferred from the primary care practice, or when the practice left the database. Data were not collected on ethnicity. We recorded antipsychotic prescriptions using the date a prescription was issued. As CPRD prescriptions are not linked to indications, we developed an algorithm to ascertain the most likely indication associated with participants' first antipsychotic prescription using clinical codes. We reported prescribing trends as annual period prevalence and the rate of first antipsychotic prescription, and we used joinpoint regression analysis to identify changes in the outcome trend. We stratified prevalence estimates by age group, gender, and Index of Multiple Deprivation quintiles, we reported frequencies of likely indications associated with incident prescriptions, and we explored clinical preference for typical versus atypical antipsychotics within deprivation quintiles.

FINDINGS

Between Jan 1, 2000, and Dec 31, 2019, we included 7 216 791 children and adolescents, of whom 3 480 730 (48·2%) were girls and 3 736 061 (51·8%) were boys, with a mean age at the start of follow-up of 7·3 years (SD 4·9; range 3-18). Median follow-up was 4·1 years (IQR 1·5-8·5). 19 496 (0·3%) individuals received 243 529 antipsychotic prescriptions over follow-up, including 225 710 (92·7%) atypical and 17 819 (7·3%) typical antipsychotic prescriptions. The annual period prevalence of antipsychotic prescriptions rose from 0·057% (95% CI 0·052-0·063%) in 2000 to 0·105% (0·100-0·111%) in 2019. From joinpoint analyses, the period prevalence of all antipsychotic prescriptions increased by an average of 3·3% per year (2·2-4·9%) and the rate of first prescriptions increased by 2·2% per year (1·7-2·7%). The most likely indications of the first identified antipsychotic prescriptions were for autism spectrum disorder (2477 [12·7%]), non-affective psychosis (1669 [8·6%]), anxiety disorders (1466 [7·5%]), ADHD (1391 [7·1%]), depression (1256 [6·4%]), and conduct disorders (1181 [6·1%]).

INTERPRETATION

The observed increase in antipsychotic prescriptions over 20 years results from the accumulation of repeated prescriptions to the same individuals combined with an increase in new prescriptions. These findings highlight the need for continued monitoring of trends in antipsychotic use and, although this was not examined in this paper, the findings highlights the need for better information about long-term antipsychotic safety.

FUNDING

None.

Validation of a pandemic-proof, decentralized cardiovascular trial: scalable design produces rapid recruitment, high engagement and protocol adherence in DeTAP (Decentralized Trial in Afib Patients)

Background

The COVID-19 pandemic has curtailed clinical trial activity significantly. Decentralized clinical trial (DCT) designs may lower cost, expand trial access, and reduce exposure risk for patients and staff. Whether such designs can be used for large, pivotal drug trials is not known.

Purpose

We performed a feasibility study to inform whether a large phase 3 Cardiovascular DCT can achieve high quality trial results and also withstand health crises such as the COVID-19 pandemic. The DeTAP (Decentralized Trial in Afib Patients) was a single-arm, observational study that integrated a suite of digital health technologies, including paired home sensor devices, into a 100% virtual trial experience for atrial fibrillation (AF) patients on anticoagulation.

Methods

We recruited 100 AF patients over age 55 on oral anticoagulation (OAC) by traditional methods or by social media ads placed California-wide. Subjects completed an online prescreening, uploaded their active OAC prescription, and completed an e-consent via SMS message link. Participants downloaded a customized study app to integrate surveys and data from study-supplied wireless blood pressure (BP) and 6 lead EKG sensors (Figure 1A). Participants completed pre- and post-study engagement surveys, weekly OAC adherence surveys, 4 study televisits, 4 ECG/BP readings, and 4 post-study surveys over a 6 month period. The primary endpoints were protocol engagement-based measurements that quantified percent completion of: 1) televisits 2) surveys, 3) ECG/BP readings requirements. Secondary endpoints were the % changes in: 1) OAC adherence (OACA), 2) nuisance bleeding (NB), 3) individual patient engagement surveys.

Results

100 participants were recruited in 26 days (traditional: 6 in 2 weeks; social media: 94 in 12 days) with a dramatic surge in enrollment driven by social media ads (Figure 1B, Table). A recruitment overflow occurred with &gt;200 eligible candidates on a waitlist. All key study completion metrics showed high compliance: televisit (91%); surveys (85%); ECG/BP completion (90%). Overall OACA was unchanged, but for subjects who reported low initial OACA, there was significant improvement at 6 months (85±16% to 98±6%; p=0.002). 47 participants (57%) reported NB, which did not correlate with OACA. Participant engagement measure scores (PAM-13) trended higher (baseline, 70%; 6 months, 74%, p=0.32). Lastly, study participants exhibited strong interest in participating in a larger experimental drug DCT study (90%) in the future.

Conclusion

The DeTAP study, conducted fully during the COVID-19 pandemic, demonstrates that a decentralized CV medical intervention trial is feasible and can achieve rapid recruitment, high study retention, physiologic and adverse event reporting, and high study engagement via the proper integration of digital technologies and a dedicated DCT study coordination effort. These findings could be informative for virtualizing large pivotal clinical trials at scale.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bayer AG Figure 1. DeTAP Study Design and Recruitment TimelineTable 1. DeTAP Results

Prediction models for child and adolescent mental health: A systematic review of methodology and reporting in recent research

BACKGROUND

There has been a rapid growth in the publication of new prediction models relevant to child and adolescent mental health. However, before their implementation into clinical services, it is necessary to appraise the quality of their methods and reporting. We conducted a systematic review of new prediction models in child and adolescent mental health, and examined their development and validation.

METHOD

We searched five databases for studies developing or validating multivariable prediction models for individuals aged 18 years old or younger from 1 January 2018 to 18 February 2021. Quality of reporting was assessed using the Transparent Reporting of a multivariable prediction models for Individual Prognosis Or Diagnosis checklist, and quality of methodology using items based on expert guidance and the PROBAST tool.

RESULTS

We identified 100 eligible studies: 41 developing a new prediction model, 48 validating an existing model and 11 that included both development and validation. Most publications (k = 75) reported a model discrimination measure, while 26 investigations reported calibration. Of 52 new prediction models, six (12%) were for suicidal outcomes, 18 (35%) for future diagnosis, five (10%) for child maltreatment. Other outcomes included violence, crime, and functional outcomes. Eleven new models (21%) were developed for use in high-risk populations. Of development studies, around a third were sufficiently statistically powered (k = 16%, 31%), while this was lower for validation investigations (k = 12, 25%). In terms of performance, the discrimination (as measured by the C-statistic) for new models ranged from 0.57 for a tool predicting ADHD diagnosis in an external validation sample to 0.99 for a machine learning model predicting foster care permanency.

CONCLUSIONS

Although some tools have recently been developed for child and adolescent mental health for prognosis and child maltreatment, none can be currently recommended for clinical practice due to a combination of methodological limitations and poor model performance. New work needs to use ensure sufficient sample sizes, representative samples, and testing of model calibration.

Risk factors for suicide in prisons: a systematic review and meta-analysis

BACKGROUND

Rates of suicide among people in prison are elevated compared with people of similar age and sex who are living in the community. Improving assessments and interventions to reduce suicide risk requires updated evidence on risk factors. We aimed to examine risk factors associated with suicide in prisoners.

METHODS

We did an updated systematic review and meta-analysis of risk factors for suicide among people in prison. We searched five biblographic databases for articles published between Jan 1, 2006, and Aug 13, 2020, and one database for articles published between Jan 1, 1973, and Aug 13, 2020. Eligible studies reported risk factors in individuals who died by suicide while in prison and in controls from the general prison population. Two reviewers independently extracted data for each study using a standardised form. We calculated random-effects pooled odds ratios (ORs) for the association of suicide with demographical, clinical, criminological, and institutional risk factors, and investigated heterogeneity using subgroup and meta-regression analyses. This systematic review is registered with PROSPERO, CRD42020137979.

FINDINGS

We identified 8041 records through our searches, and used 77 eligible studies from 27 countries, including 35 351 suicides, in the main analysis. The strongest clinical factors associated with suicide were suicidal ideation during the current period in prison (OR 15·2, 95% CI 8·5-27·0), a history of attempted suicide (OR 8·2, 4·4-15·3), and current psychiatric diagnosis (OR 6·4, 3·6-11·1). Institutional factors associated with suicide included occupation of a single cell (OR 6·8, 2·3-19·8) and having no social visits (OR 1·9, 1·5-2·4). Criminological factors included remand status (OR 3·6, 3·1-4·1), serving a life sentence (OR 2·4, 1·3-4·6), and being convicted of a violent offence, in particular homicide (OR 3·1, 2·2-4·2).

INTERPRETATION

Several modifiable risk factors, such as psychiatric diagnosis, suicidal ideation during the current period in prison, and single-cell occupancy, are associated with suicide among people in prison. Preventive interventions should target these risk factors and include improved access to evidence-based mental health care. Understanding other factors associated with suicide might improve risk stratification and resource allocation in prison services.

FUNDING

Wellcome Trust, National Institute for Health Research Applied Research Collaboration Oxford and Thames Valley.

The economic impact of violence perpetration in severe mental illness: a retrospective, prevalence-based analysis in England and Wales

Background

Calls for increased funding for mental health services require many lines of evidence in support, including estimates of economic impact. One understudied source of cost is violence perpetrated by individuals with severe mental illness. Estimating this economic impact can inform budget planning across several government sectors and emphasise the importance of violence prevention. Therefore, we aimed to provide a comprehensive estimate of the economic costs of violence perpetrated by people with severe mental illness.

Methods

For this retrospective analysis, we used a prevalence-based modelling approach to estimate the annual economic cost of violent incidents committed by people with severe mental illness in England and Wales during 2015–16. The model was based on secondary data, including the association between violence and severe mental illness, illness prevalence, recidivism, absolute numbers of violent incidents in 2015–16, and costs to society per violent crime, by area of spending. Uncertainty was addressed with probabilistic and deterministic sensitivity analyses that tested the effect of underreporting of domestic violence and distributions of crime types in individuals with severe mental illness.

Outcomes

The estimated annual economic impact of violence perpetrated by people with severe mental illness was £2·5 (95% CI 1·4–4·5) billion in England and Wales in 2015–16, or 5·3% of the total estimated societal cost of violence. The largest contributors to the cost of violent crime perpetrated by individuals with severe mental illness were the cost of physical and emotional harm to victims (£1·4 [95% CI 0·8–2·5] billion), followed by lost productivity of victims (£348.0 [190·0–628·8] million), while the combined cost to the police and criminal justice system was £561·3 (305·9–1009·2) million and the cost to health services was £136·7 [74·3–246·3] million. The additional cost to secure forensic care was estimated to be £487·7 (302·0–709·1) million.

Interpretation

The economic impact of violence perpetrated by individuals with severe mental illness is potentially important. Preventing violence, especially through services for individuals with comorbid substance misuse, and reducing recidivism might lead to cost savings at a governmental and individual level, in addition to the clinical and societal benefits.

Funding

Wellcome Trust, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, and NIHR Applied Research Collaboration Oxford and Thames Valley.

Measuring an individual researcher's impact: new directions and challenges

Metrics which quantify the impact of a scientist are increasingly incorporated into decisions about how to rate and fund individuals and institutions. Several commonly used metrics, based on journal impact factors and citation counts, have been criticised as they do not reliably predict real-world impact, are highly variable between fields and are vulnerable to gaming. Bibliometrics have been incorporated into systems of research assessment but these may create flawed incentives, failing to reward research that is validated, reproducible and with wider impacts. A recent proposal for a new standardised citation metric based on a composite indicator of 6 measures has led to an online database of 100 000 of the most highly cited scientists in all fields. In this perspective article, we provide an overview and evaluation of this new citation metric as it applies to mental health research. We provide a summary of its findings for psychiatry and psychology, including clustering in certain countries and institutions, and outline some implications for mental health research. We discuss strengths and limitations of this new metric, and how further refinements could align impact metrics more closely with wider goals of scientific research.

Identifying Predictors of Suicide in Severe Mental Illness: A Feasibility Study of a Clinical Prediction Rule (Oxford Mental Illness and Suicide Tool or OxMIS)

BACKGROUND

Oxford Mental Illness and Suicide tool (OxMIS) is a brief, scalable, freely available, structured risk assessment tool to assess suicide risk in patients with severe mental illness (schizophrenia-spectrum disorders or bipolar disorder). OxMIS requires further external validation, but a lack of large-scale cohorts with relevant variables makes this challenging. Electronic health records provide possible data sources for external validation of risk prediction tools. However, they contain large amounts of information within free-text that is not readily extractable. In this study, we examined the feasibility of identifying suicide predictors needed to validate OxMIS in routinely collected electronic health records.

METHODS

In study 1, we manually reviewed electronic health records of 57 patients with severe mental illness to calculate OxMIS risk scores. In study 2, we examined the feasibility of using natural language processing to scale up this process. We used anonymized free-text documents from the Clinical Record Interactive Search database to train a named entity recognition model, a machine learning technique which recognizes concepts in free-text. The model identified eight concepts relevant for suicide risk assessment: medication (antidepressant/antipsychotic treatment), violence, education, self-harm, benefits receipt, drug/alcohol use disorder, suicide, and psychiatric admission. We assessed model performance in terms of precision (similar to positive predictive value), recall (similar to sensitivity) and F1 statistic (an overall performance measure).

RESULTS

In study 1, we estimated suicide risk for all patients using the OxMIS calculator, giving a range of 12 month risk estimates from 0.1-3.4%. For 13 out of 17 predictors, there was no missing information in electronic health records. For the remaining 4 predictors missingness ranged from 7-26%; to account for these missing variables, it was possible for OxMIS to estimate suicide risk using a range of scores. In study 2, the named entity recognition model had an overall precision of 0.77, recall of 0.90 and F1 score of 0.83. The concept with the best precision and recall was medication (precision 0.84, recall 0.96) and the weakest were suicide (precision 0.37), and drug/alcohol use disorder (recall 0.61).

CONCLUSIONS

It is feasible to estimate suicide risk with the OxMIS tool using predictors identified in routine clinical records. Predictors could be extracted using natural language processing. However, electronic health records differ from other data sources, particularly for family history variables, which creates methodological challenges.

Measuring Disturbance of the Endocannabinoid System in Psychosis: A Systematic Review and Meta-analysis

IMPORTANCE

The endocannabinoid system (ECS) is a lipid-based endogenous signaling system. Its relevance to psychosis is through the association between cannabis use and the onset and course of illness and through the antipsychotic properties of cannabidiol, a potential ECS enhancer.

OBJECTIVE

To conduct a systematic review and meta-analysis of the blood and cerebrospinal fluid (CSF) measures of the ECS in psychotic disorders.

DATA SOURCES

Web of Science and PubMed were searched from inception through June 13, 2018. The articles identified were reviewed, as were citations to previous publications and the reference lists of retrieved articles.

STUDY SELECTION

Original articles were included that reported blood or CSF measures of ECS activity in patients with psychotic illnesses and in healthy controls.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines, independent extraction by multiple observers, and random-effects meta-analysis were used. Heterogeneity was assessed with the I2 index. Sensitivity analyses tested the robustness of the results.

MAIN OUTCOMES AND MEASURES

The clinical relevance of ECS modifications in psychotic disorders was investigated by (1) a quantitative synthesis of the differences in blood and CSF markers of the ECS between patients and healthy controls, and (2) a qualitative synthesis of the association of these markers with symptom severity, stage of illness, and response to treatment.

RESULTS

A total of 18 studies were included. Three individual meta-analyses were performed to identify the differences in ECS markers between people with schizophrenia and healthy controls. Five studies, including 226 patients and 385 controls, reported significantly higher concentrations of anandamide in the CSF of patients than controls (standardized mean difference [SMD], 0.97; 95% CI, 0.67-1.26; P < .001; I2 = 54.8%). In 9 studies, with 344 patients and 411 controls, significantly higher anandamide levels in blood were found in patients, compared with controls (SMD, 0.55; 95% CI, 0.05-1.04; P = .03; I2 = 89.6%). In 3 studies, involving 88 patients and 179 controls, a significantly higher expression of type 1 cannabinoid receptors on peripheral immune cells was reported in patients compared with controls (SMD, 0.57; 95% CI, 0.31-0.84; P < .001; I2 = 0%). Higher ECS tone was found at an early stage of illness in individuals who were antipsychotic naïve or free, and it had an inverse association with symptom severity and was normalized after successful treatment. Moderate to high level of heterogeneity in methods was found between studies.

CONCLUSIONS AND RELEVANCE

Testing clinically relevant markers of the ECS in the blood and CSF of people with psychotic illness appears possible, and these markers provide useful biomarkers for the psychotic disorder; however, not all studies accounted for important variables, such as cannabis use.

TRIAL REGISTRATION

PROSPERO identifier: CRD42018099863.

Trabeculectomy training in England: are we safe at training? Two year surgical outcomes

OBJECTIVES

To define the safety profile of trainee trabeculectomy surgery in the United Kingdom. Surgical exposure for trainees in England is limited due to service requirements, the European working time directive constraints and increasing sub-specialisation of glaucoma surgery. Limited knowledge exists on the outcomes of supervised glaucoma surgery. The aim is to determine the safety of supervised trabeculectomy surgery performed by trainee ophthalmologists.

METHODS

Retrospective case note review of all patients that had trabeculectomy surgery with MMC by consultant and trainee surgeons across multiple UK centres. All eyes have 2-year follow up. Success was determined using WGA guidelines. Two-tailed p values were obtained using Fisher's exact test to ascertain statistical significance between groups.

MAIN OUTCOME MEASURES

intraocular pressure, visual acuity, success and failure rates.

RESULTS

324 eyes were reviewed. 211 (66.4%) cases were performed by glaucoma consultants, 107(33.6%) by trainee ophthalmologists. The majority of eyes in each group were undergoing surgery for POAG. Post-operative IOP control showed no significant difference between consultant and trainee groups at year 1 and year 2. Success rates showed no significant difference between consultant and trainee cases. Failure rates at year 1 showed a significant difference between the two groups. No significant difference was seen at year 2. The trainee group had significantly more complications, when compared with the consultant group. Snellen visual acuity loss was not statistically significant between the two groups at the 2 year time point.

CONCLUSIONS

The outcomes of supervised trainee trabeculectomy compare favourably with consultant cases after 2 year follow up. Trainee cases had higher complication rates than consultant cases. Bleb leaks are a common complication of trainee cases, where closer supervision may be required. There is potential for surgical simulation to help increase the success of such cases. These findings may encourage trainee participation in glaucoma surgery.

Long-term benefits and adverse effects of intermittent versus daily glucocorticoids in boys with Duchenne muscular dystrophy

OBJECTIVE

To assess the current use of glucocorticoids (GCs) in Duchenne muscular dystrophy in the UK, and compare the benefits and the adverse events of daily versus intermittent prednisolone regimens.

DESIGN

A prospective longitudinal observational study across 17 neuromuscular centres in the UK of 360 boys aged 3-15 years with confirmed Duchenne muscular dystrophy who were treated with daily or intermittent (10 days on/10 days off) prednisolone for a mean duration of treatment of 4 years.

RESULTS

The median loss of ambulation was 12 years in intermittent and 14.5 years in daily treatment; the HR for intermittent treatment was 1.57 (95% CI 0.87 to 2.82). A fitted multilevel model comparing the intermittent and daily regiments for the NorthStar Ambulatory Assessment demonstrated a divergence after 7 years of age, with boys on an intermittent regimen declining faster (p<0.001). Moderate to severe side effects were more commonly reported and observed in the daily regimen, including Cushingoid features, adverse behavioural events and hypertension. Body mass index mean z score was higher in the daily regimen (1.99, 95% CI 1.79 to 2.19) than in the intermittent regimen (1.51, 95% CI 1.27 to 1.75). Height restriction was more severe in the daily regimen (mean z score -1.77, 95% CI -1.79 to -2.19) than in the intermittent regimen (mean z score -0.70, 95% CI -0.90 to -0.49).

CONCLUSIONS

Our study provides a framework for providing information to patients with Duchenne muscular dystrophy and their families when introducing GC therapy. The study also highlights the importance of collecting longitudinal natural history data on patients treated according to standardised protocols, and clearly identifies the benefits and the side-effect profile of two treatment regimens, which will help with informed choices and implementation of targeted surveillance.

Prospective evaluation of postoperative pain in cats undergoing ovariohysterectomy by a midline or flank approach

Twenty entire female cats were randomly assigned to two groups of 10; the cats in one group underwent ovariohysterectomy by a midline approach and the cats in the other group by a flank approach. Cats were assessed for signs of pain and scores were assigned pre- and postoperatively. There was a tendency for the cats neutered by a flank approach to be in more pain postoperatively (P=0.05). The final pain score for cats in either group was equal to or lower than their baseline score.

Postanaesthetic cerebral necrosis in five horses

After being anaesthetised for between one hour 40 minutes and seven hours, five adult horses developed acute neurological signs and extensive cerebrocortical necrosis. Four of them had had abdominal surgery for colic and one had had repeated orthopaedic interventions. Between five hours and seven days after the surgery, all five horses suddenly developed severe signs of a predominantly prosencephalic disturbance: bilateral blindness with normal pupillary light responses, abnormal behaviour varying from propulsive pacing to head pressing profound lethargy and generalised seizures. They were euthanased between 24 hours and three weeks after the onset of these signs. In three of the cases a gross examination of the brain revealed patchy malacia of the cerebral grey matter and some discolouration of the adjacent white matter. Microscopical examination revealed lesions that varied from laminar neuronal necrosis in the grey matter of the cerebral cortex to more diffuse necrosis of the cortex and underlying white matter. Four of the five cases had had a period of hypercapnea while anaesthetised, and two of them (and possibly a third) had also had hypoxaemia.

Urban-rural mortality differentials: controlling for material deprivation

This paper investigates the relationship between premature mortality and material deprivation, and the differences in this relationship between urban and rural areas. We examine, given comparable measures of affluence or deprivation, whether residual differences exist between urban and rural areas for all-causes of death and, separately, for cancers, circulatory and respiratory diseases. Using 1990-92 mortality data for the 908 wards of Wales we apply statistical analyses based on tabular data and parametric Poisson regression models. Contrasts are sought between six urban and rural categories defined in terms of settlement sizes and the employment structure of rural areas. Inequalities in all-cause premature mortality are widest in the cities, narrowest in the deeper rural areas, and of intermediate and comparable value in other areas of Wales. This is largely a reflection of the different distributions of material deprivation in these areas. After controlling for differences in socio-economic characteristics, using deprivation measures, the tendency for lower mortality in deeper rural areas is substantially reduced. Residual mortality differences between urban and rural areas are shown to be dependent on the way deprivation is measured and the disease group under study. For cancers there are no residual mortality differences, while for respiratory and circulatory diseases some of the residual variation can be accounted for by employment variables, particularly previous employment in the coal mining industry.

Assessment of the Abbott IMx assay system for the measurement of human chorionic gonadotropin levels in the treatment of ectopic pregnancy

The rapid, accurate determination of serum human chorionic gonadotropin (beta-hCG) levels in the 900- to 2000-IU/L range is a critical element in the treatment of patients with suspected ectopic pregnancy. Using the Abbott IMx system (Abbott Laboratories, North Chicago, Ill), beta-hCG levels can be determined on an undiluted sample up to 1000 IU/L. A sample with beta-hCG level greater than 1000 IU/L is automatically diluted and the diluted sample redetermined. Unfortunately, employing a 1:200 fixed dilution can produce a working sample that contains an beta-hCG concentration that does not fall on a linear portion of the standard curve (<7.5 IU/L). This results in a calculated beta-hCG concentration (200 x observed value) that has high error (coefficient of variation up to 21.8%). Additionally, interfering substances in the reagents, which vary in quantity from lot to lot of reagents, further confound accurate beta-hCG determination by the system. Consequently, the Abbott IMx assay system cannot be used as recommended by the manufacturer for routine measurement of serum beta-hCG in the 900- to 2000-IU range. An alternate protocol employing at 1:10 dilution would allow a more accurate beta-hCG determination.

Interference by human anti-mouse antibody in two-site immunoassays

Studies with goat and rabbit anti-mouse antibody, as models of human anti-mouse antibody (HAMA), have shown that several of the commonly used two -site immunoassays (e.g., for CA-125, carcinoembryonic antigen, choriogonadotropin, lutropin, hepatitis B surface antigen, thyrotropin) are susceptible to interference by this type of bridging heterophile antibody. In most cases the interference can be blocked by incubation with mouse IgG. We studied HAMA interference in an assay of hepatitis B surface antigen by using HAMA-positive sera from a transplant patient given OKT3 and from a cancer patient given CYT-103 (modified antibody B72.3). The HAMA interference attributable to the OKT3 could be blocked by incubation with mouse IgG at room temperature. In contrast, the interference caused by the B72.3-induced HAMA could be blocked by prolonged incubation with high concentrations of the B72.3 antibody at 4 degrees C. A limited survey of 50 hospital patients selected without conscious bias revealed two HAMA-positive patients, only one of whom was known to have been exposed to mouse immunoglobulin. HAMA interferences are currently a minor problem in routine laboratory medicine, but the increasing use of diagnostic and therapeutic products involving mouse-origin monoclonal antibodies will make the detection and elimination of HAMA interferences an important part of laboratory practice in the future.

Interference by human anti-mouse antibody in two-site immunoassays

Studies with goat and rabbit anti-mouse antibody, as models of human anti-mouse antibody (HAMA), have shown that several of the commonly used two -site immunoassays (e.g., for CA-125, carcinoembryonic antigen, choriogonadotropin, lutropin, hepatitis B surface antigen, thyrotropin) are susceptible to interference by this type of bridging heterophile antibody. In most cases the interference can be blocked by incubation with mouse IgG. We studied HAMA interference in an assay of hepatitis B surface antigen by using HAMA-positive sera from a transplant patient given OKT3 and from a cancer patient given CYT-103 (modified antibody B72.3). The HAMA interference attributable to the OKT3 could be blocked by incubation with mouse IgG at room temperature. In contrast, the interference caused by the B72.3-induced HAMA could be blocked by prolonged incubation with high concentrations of the B72.3 antibody at 4 degrees C. A limited survey of 50 hospital patients selected without conscious bias revealed two HAMA-positive patients, only one of whom was known to have been exposed to mouse immunoglobulin. HAMA interferences are currently a minor problem in routine laboratory medicine, but the increasing use of diagnostic and therapeutic products involving mouse-origin monoclonal antibodies will make the detection and elimination of HAMA interferences an important part of laboratory practice in the future.

Influence of dangling thymidine residues on the stability and structure of two DNA duplexes

We have employed temperature-dependent UV spectroscopy, circular dichroism (CD), 400-MHz proton nuclear magnetic resonance (NMR), and computer modeling to characterize both structurally and thermodynamically the influence of unpaired, dangling thymidine residues (T) on the thermal stability and melting behavior of two DNA core duplexes. The specific DNA double helices that we have investigated in this work are core duplexes [d(GC)3]2 (I) and [d(CG)3]2 (IV), 3' dangling T derivatives [d[(GC)3TT]]2 (II) and [d[(CG)3TT]]2 (V), and 5' dangling T derivatives [d[TT(GC)3]]2 (III) and [d[TT(CG)3]]2 (VI). Our experimental data allow us to reach the following conclusions: (1) For both core duplexes (I and IV), the addition of dangling T residues on either the 5' or 3' end causes an increase in the optical melting temperature tm. (2) For both core duplexes, 5' dangling T residues induce a greater increase in the optical tm's than 3' dangling T residues. (3) For both cores duplexes, the increase in tm induced by the addition of dangling T residues is enthalpic in origin, with 5' dangling T residues inducing a greater increase in the van't Hoff transition enthalpy than 3' dangling T's. (4) Dangling T residues cause downfield shifts in all of the nonexchangeable aromatic protons of the [d(GC)3]2 core duplex (I), with the 5' T residues inducing the largest shifts. For the most part, this trend does not hold with the [d(CG)3]2 core duplex (IV). (5) For both core duplexes, the addition of dangling T residues causes an increase in the NMR tm's of almost all the nonexchangeable aromatic protons of the core duplex.(ABSTRACT TRUNCATED AT 250 WORDS)

Methylation of thymine residues during oligonucleotide synthesis

Thymine residues in an oligodeoxyribonucleotide are subject to methylation at N3 by the internucleotide methyl phosphotriester linkages. This alkylation occurs most rapidly in the presence of a strong base such as DBU, but also takes place, at a much slower rate, during oligonucleotide synthesis.