Examining the effect of manganese on physiological processes: Invertebrate models

Manganese (Mn²⁺ as MnSO₄ &/or MnCl₂) is a common and essential element for maintaining life in plants and animals and is found in soil, fresh waters and marine waters; however, over exposure is toxic to organisms. MnSO₄ is added to soil for agricultural purposes and people are exposed to Mn²⁺ in the mining industry. Hypermanganesemia in mammals is associated with neurological issues mimicking Parkinson's disease (PD) and appears to target dopaminergic neural circuits. However, it also seems that hypermanganesemia can affect many aspects of health besides dopaminergic synapses. We examined the effect on development, behavior, survival, cardiac function, and glutamatergic synaptic transmission in the Drosophila melanogaster. In addition, we examined the effect of Mn²⁺ on a sensory proprioceptive organ and nerve conduction in a marine crustacean and synaptic transmission at glutamatergic neuromuscular junctions of freshwater crayfish. A dose-response effect of higher Mn²⁺ retards development, survival and cardiac function in larval Drosophila and survival in larvae and adults. MnSO₄ as well as MnCl₂ blocks stretch activated responses in primary proprioceptive neurons in a dose-response manner. Mn²⁺ blocks glutamatergic synaptic transmission in Drosophila as well as crayfish via presynaptic action. This study is relevant in demonstrating the effects of Mn²⁺ on various physiological functions in order to learn more about acute and long-term consequences Mn²⁺ exposure.

Use of alcohol intoxication codes for serious non-fatal hospitalised injury

AIM

To determine the extent to which ICD-10 alcohol intoxication codes are used for serious hospitalised injury and the distribution of these codes according to gender, age, injury mechanism and intent, severity of injury, and whether the patient was treated in an Intensive Care Unit.

DESIGN

Cross-sectional study.

SETTING

New Zealand.

PARTICIPANTS

All injury hospital discharges in 2010 that met specified severity criteria.

MEASUREMENTS

Cases which had a measurement of BAC (Y90) coded, or only a subjective assessment of alcohol intoxication (F10.0).

FINDINGS

2.5% had a blood alcohol recorded (Y90) and a further 3% were coded as being intoxicated but there was no blood alcohol code. All factors investigated were shown to be independently associated with the assignation of codes. Notable findings were the elevated odds of an alcohol code for males, assault and the more severe injuries.

CONCLUSIONS

Assessment of alcohol intoxication among seriously injured persons appears to be very uncommon. The development of a standardised instrument for clinical judgement of intoxication would be highly desirable.

Developing valid indicators of injury incidence for "all injury"

BACKGROUND/AIMS

This paper focuses on the methods used to develop indicators for "all injury" incidence for the New Zealand Injury Prevention Strategy (NZIPS), launched in June 2003. Existing and previously proposed New Zealand national non-fatal injury indicators exhibited threats to validity. Population/

SETTING

The total population of New Zealand.

METHODS

The authors proposed fatal and new non-fatal injury indicators for "all injury" based on national mortality and hospitalizations data. All of the candidate indicators were subjected to a systematic assessment of validity, using the International Collaborative Effort on Injury Statistics (ICE) criteria. Based on the results of that validation, the authors identified four proposed NZIPS indicators.

RESULTS

The proposed "all injury" indicators were as follows: age standardized injury mortality rate per 100 000 person-years at risk; number of injury deaths; age standardized serious non-fatal injury rate per 100 000 person-years at risk; and number of cases of serious non-fatal injury. The authors identified no threat-to-validity when assessed against the ICE criteria. The estimated numbers and rates of serious non-fatal injury increased over the period, in contrast to the numbers and rates of fatal injury.

CONCLUSION

The authors have proposed serious non-fatal injury indicators that they judge suffer substantially less bias than traditional non-fatal injury indicators. This approach to indicator development is consistent with the view that before newly proposed indicators are promulgated, they should be subjected to formal validation. The authors are encouraged that the New Zealand Government has accepted these arguments and proposed indicators, and are starting to act on some of their recommendations, including the development of complementary indicators.

Injury outcome indicators: the development of a validation tool

BACKGROUND

Researchers have previously expressed concern about some national indicators of injury incidence and have argued that indicators should be validated before their introduction.

AIMS

To develop a tool to assess the validity of indicators of injury incidence and to carry out initial testing of the tool to explore consistency on application.

METHODS

Previously proposed criteria were shared for comment with members of the International Collaborative Effort on Injury Statistics (ICE) Injury Indicators Group over a period of six months. Immediately after, at a meeting of Injury ICE in Washington, DC in April 2001, revised criteria were agreed over two days of meetings. The criteria were applied, by three raters, to six non-fatal indicators that underpin the national road safety targets for Canada, New Zealand, and the United Kingdom. Consistency of ratings were judged. CONSENSUS OUTCOME: The development process resulted in a validation tool that comprised criteria relating to: (1) case definition, (2) a focus on serious injury, (3) unbiased case ascertainment, (4) source data for the indicator being representative of the target population, (5) availability of data to generate the indicator, and (6) the existence of a full written specification for the indicator. On application of these criteria to the six road safety indicators, some problems of agreement between raters were identified.

CONCLUSION

This paper has presented an early step in the development of a tool for validating injury indicators, as well as some directions that can be taken in its further development.

Traps for the unwary in estimating person based injury incidence using hospital discharge data

BACKGROUND

Injuries resulting in admission to hospital provide an important basis for determining priorities, emerging issues, and trends in injury. There are, however, a number of important issues to be considered in estimating person based injury incidence using such data. Failure to consider these could result in significant overestimates of incidence and incorrect conclusions about trends.

AIM

To demonstrate the degree to which estimates of the incidence of person based injury requiring hospital inpatient treatment vary depending on how one operationally defines an injury, and whether or not day patients, readmissions, and injury due to medical procedures are included.

METHOD

The source of data for this study was New Zealand's National Minimum Dataset. The primary analyses were of a dataset of all 1989-98 discharges from public hospital who had an external cause of injury and poisoning code assigned to them.

RESULTS

The results show that estimates of the incidence of person based injury vary significantly depending on how one operationally defines an injury, and whether day patients, readmissions, and injury due to medical procedures are included. Moreover the effects vary significantly by pathology and over time.

CONCLUSIONS

(1) Those using New Zealand hospital discharge data for determining the incidence of injury should: (a) select cases which meet the following criteria: principal diagnosis injury only cases, patients with day stay of one day or more, and first admissions only, (b) note in their reporting that the measure is an estimate and could be as high as a 3% overestimate. (2) Other countries with similar data should investigate the merit of adopting a similar approach. (3) That the International Collaborative Effort on Injury Statistics review all diagnoses within International Classification of Diseases 9th and 10th revisions with a view to reaching consensus on an operational definition of an injury.

Hip protector compliance among older people living in residential care homes

OBJECTIVES

To estimate the compliance rates for the use of hip protectors among people living in residential care homes. Population/setting: People aged 65 years and over living in residential care homes with 20 or more beds in East Kent, south east England.

METHODS

Seventeen homes with the highest historical frequency of hip fractures were selected. All residents were offered SAFEHIP hip protectors. Care staff recorded daily hip protector compliance on diary cards over six months. Compliance rates were estimated from the number of sessions (morning, afternoon, evening, night) that a person wore hip protectors.

RESULTS

A total of 153 (51%) out of 299 residents agreed to wear hip protectors The 24 hour compliance rate for those who were issued with hip protectors and wore them at least once was 29%: 37% in the daytime and 3% at night. Daytime compliance rates reduced from 47% for the first month, to around 30% for months 5 and 6.

CONCLUSION

This study highlights the problems of persuading older people living in residential care homes to wear hip protectors. They have been shown to prevent hip fracture in nursing home (high risk) populations, and a recent trial showed their effectiveness in a mixed geriatric population. People living in residential care homes are also at greater risk of falling and fracturing than their counterparts living in the community. Initiatives to prevent hip fracture within residential care homes are also justified.

Measure for measure: the quest for valid indicators of non-fatal injury incidence

In this edition of Public Health, McClure and colleagues report on research that considered the criterion validity of indicators based on serious long bone fracture and length of stay in hospital. They found that neither were sensitive or specific indicators for serious injury as defined by an Injury Severity Score (ISS) of 16 or more. They contend that their study findings ' em leader strongly support a return to a measure similar in intent to that encapsulated in the original UK Green Paper em leader '. We contend that their analysis does not provide any empirical evidence to support their view that there should be a return to the Green Paper: Our Healthier Nation indicator. Furthermore, we consider the analyses that they carry out to validate both the Saving Lives: Our Healthier Nation and the serious long bone fracture indicators are flawed. We agree that national (or state) indicators are very influential. They encourage preventive action and resource use aimed at producing favourable changes to these indicators. However, each of the four non-fatal indicators considered in their analysis have problems. Formal validation of existing indicators is necessary and the following aspects of validity should be addressed: face; criterion; consistency; and completeness and accuracy of the source date. Taking into account the current national data systems in England, possible options for one or more national non-fatal unintentional injury indicators have been proposed in our paper. Furthermore, the International Collaborative Effort on Injury Statistics (ICE) Injury Indicators Group is about to embark on the development of a strategic framework for the development of valid indicators of non-fatal injury occurrence.

Are we blind to injuries in the visually impaired? A review of the literature

OBJECTIVES

To review the literature on the risks and types of injuries associated with visual impairment, and to identify pertinent areas for future research.

METHODS

A search of bibliographic databases was conducted in April 2000 for studies published since 1980 and selected studies that met two or more of the following criteria: formal ophthalmic assessment was used; adjustment for confounding variables; large sample size including numbers of visually impaired; and clear definitions and outcomes.

RESULTS

Thirty one studies were selected. The majority of these studies (20) assessed falls (including eight on hip fracture and four on multiple falls), eight studies reported traffic related injuries, and three studies assessed occupational injury. The evidence on falls, which relate predominantly to older people, suggests that those with reduced visual acuity are 1.7 times more likely to have a fall and 1.9 times more likely to have multiple falls compared with fully sighted populations. The odds of a hip fracture are between 1.3 and 1.9 times greater for those with reduced visual acuity. Studies of less severe injuries and other causes of injury were either poorly designed, underpowered, or did not exist.

CONCLUSIONS

There are substantial gaps in research on both injuries to which people with visual impairment are especially susceptible and in evaluating interventions to reduce these injuries. It is recommended that in future studies the minimum data captured includes: formal ophthalmic assessment of visual fields and visual acuity, outcome measurement, control for confounders, and the costs of health care resource use and any interventions.

Sample size calculations for intervention trials in primary care randomizing by primary care group: an empirical illustration from one proposed intervention trial

Because of the central role of the general practice in the delivery of British primary care, intervention trials in primary care often use the practice as the unit of randomization. The creation of primary care groups (PCGs) in April 1999 changed the organization of primary care and the commissioning of secondary care services. PCGs will directly affect the organization and delivery of primary, secondary and social care services. The PCG therefore becomes an appropriate target for organizational and educational interventions. Trials testing these interventions should involve randomization by PCG. This paper discusses the sample size required for a trial in primary care assessing the effect of a falls prevention programme among older people. In this trial PCGs will be randomized. The sample size calculations involve estimating intra-PCG correlation in primary outcome: fractured femur rate for those 65 years and over. No data on fractured femur rate were available at PCG level. PCGs are, however, similar in size and often coterminous with local authorities. Therefore, intra-PCG correlation in fractured femur rate was estimated from the intra-local authority correlation calculated from routine data. Three alternative trial designs are considered. In the first design, PCGs are selected for inclusion in the trial from the total population of England (eight regions). In the second design, PCGs are selected from two regions only. The third design is similar to the second except that PCGs are stratified by region and baseline value of fracture rate. Intracluster correlation is estimated for each of these designs using two methods: an approximation which assumes cluster sizes are equal and an alternative method which takes account of the fact that cluster sizes vary. Estimates of sample size required vary between 26 and 7 PCGs in each intervention group, depending on the trial design and the method used to calculate sample size. Not unexpectedly, stratification by baseline value of the outcome variable decreases the sample size required. In our analyses, geographic restriction of the population to be sampled reduces between-cluster variability in the primary outcome. This leads to an increase in precision. When allowance for variable cluster size is made, the increase in precision is not as great as would be expected with equal cluster sizes. This paper highlights the usefulness of routine data in work of this kind, and establishes one of the essential prerequisites for our proposed trial and other trials using primary outcomes with similar between-PCG variation: a feasible sample size.

The work-related fatal injury study: numbers, rates and trends of work-related fatal injuries in New Zealand 1985-1994

AIMS

To determine the number and rates of work-related fatal injuries by employment status, occupation, industry, age and gender in New Zealand 1985-1994.

METHODS

Potential cases of work-related injury deaths of persons aged 15-84 years were identified from the national electronic mortality data files. Main exclusions were deaths due to suicide and deaths due to motor vehicle crashes. The circumstances of the deaths of each fatal incident meeting inclusion criteria were then reviewed directly from coronial files to determine work-relatedness.

RESULTS

The rate of work-related fatal injury in New Zealand was 5.03/100000 workers per year for the study period. There was a significant decline in crude rate over the study period. However, this was in substantial part accounted for by changes in occupation and industry mix. Older workers, male workers, self-employed workers, and particular occupational groups, all had substantially elevated rates. Agricultural and helicopter pilots, forestry workers and fishery workers had the highest rates. Farmers, forestry workers, and fishery workers also had high numbers of deaths, together accounting for nearly 40% of all deaths.

CONCLUSIONS

This study has demonstrated that work-related fatal injury remains a pressing problem for New Zealand. Several areas in urgent need of prevention efforts were highlighted.

Newly diagnosed epilepsy: can nurse specialists help? A randomized controlled trial. Epilepsy Care Evaluation Group

PURPOSE

To describe a group of people with newly diagnosed epilepsy and to test the effect of an epilepsy nurse specialist on patients' knowledge of epilepsy, satisfaction with the advice provided, and psychological well-being.

METHODS

Neurologists in the United Kingdom (U.K.) recruited adults with newly diagnosed epilepsy. Patients were randomized to receive the offer of two appointments with an epilepsy nurse specialist or usual medical care. The main outcome measures were a questionnaire assessing patients' knowledge of epilepsy, the Hospital Anxiety and Depression Scale, and patients' reported satisfaction with the advice and explanations provided on key epilepsy-related topics.

RESULTS

Ninety people with new epilepsy completed the trial. At baseline, fewer than half the patients reported having been given enough advice on epilepsy, and there were important differences in patients' knowledge of epilepsy. Lack of a U.K. school-leaving examination pass (General Certificate School Examination) was associated with lower knowledge of epilepsy (p = 0.03). At follow-up, the patients randomized to see the nurse specialist were significantly more likely to report that enough advice had been provided on most epilepsy-related topics compared with the control group. There were no significant differences in knowledge of epilepsy scores. However, there were significant differences in the group who, at baseline, had knowledge scores in the lowest quartile; those randomized to the nurse had higher knowledge scores (42.7 vs. 37.2; p < 0.01). Compared with doctors, the nurse was highly rated for providing clear explanations.

CONCLUSIONS

Patients who have less general education have less knowledge of epilepsy. The introduction of a nurse specialist in epilepsy is associated with a significant increase in patient reports that enough advice has been provided. Nurse intervention appears to help those with the least knowledge of epilepsy improve their knowledge scores.

Head injuries to bicyclists and the New Zealand bicycle helmet law

The purpose of this study was to examine the effect of helmet wearing and the New Zealand helmet wearing law on serious head injury for cyclists involved in on-road motor vehicle and non-motor vehicle crashes. The study population consisted of three age groups of cyclists (primary school children (ages 5-12 years), secondary school children (ages 13-18 years), and adults (19+ years)) admitted to public hospitals between 1988 and 1996. Data were disaggregated by diagnosis and analysed using negative binomial regression models. Results indicated that there was a positive effect of helmet wearing upon head injury and this effect was relatively consistent across age groups and head injury (diagnosis) types. We conclude that the helmet law has been an effective road safety intervention that has lead to a 19% (90% CI: 14, 23%) reduction in head injury to cyclists over its first 3 years.

The effect of a special nurse on patients' knowledge of epilepsy and their emotional state. Epilepsy Evaluation Care Group

BACKGROUND

People with epilepsy often report being given insufficient information and support. However, there is little evidence from general practice about how much they know and how they feel.

AIM

To describe social differences in the knowledge of epilepsy of people with the condition and test the potential effect of a nurse intervention in general practice on patients' knowledge and depression levels.

METHOD

A questionnaire that included measures of knowledge, anxiety, and depression was sent to people with epilepsy aged over 15 years who were registered with 37 general practitioners. Responders were randomized to a controlled trial, offering either two appointments with an epilepsy nurse or usual care. Six months later they were reassessed.

RESULTS

Two hundred and fifty-one out of 283 (89%) of the patients with epilepsy completed questionnaires and entered the study at Stage 1. One hundred and ninety-six out of 232 (84%) of those who entered the study, who remained in the practices and were eligible, returned questionnaires at Stage 2. The average duration of epilepsy was 23 years (range 2-79 years). There were significant differences in patients' levels of knowledge of epilepsy at Stage 1. Younger people, those who had left school after 16 years of age, those with GCSEs, and people who belonged to self-help groups had higher knowledge levels, and these were independent effects. Older people and those with a recent epilepsy attack had significantly higher depression scores. Knowledge scores did not differ significantly after the nurse intervention (Stage 2). At Stage 2, the risk of depression was less in the group randomized to be offered nurse input; the effect was mainly in a subgroup of patients with no recent epilepsy attack; their risk of depression was a third of the risk in the control group.

CONCLUSIONS

Knowledge of epilepsy differs significantly, with social factors and self-help group membership having independent effects. A nurse-run clinic reduced the risk of depression for people with no recent epilepsy attack, but knowledge levels were not affected. This does not exclude the potential for patients learning more about epilepsy; it may be useful to suggest that patients join self-help groups early on.

Sexually transmitted diseases and communications with general practitioners

OBJECTIVES

To devise a method of communicating with the general practitioners (GPs), overcoming the constraints imposed by patient confidentiality and the low levels of staffing in genitourinary medicine (GUM) clinics. To assess the GPs' responses to this method of communication.

SETTING

GUM clinics at two centres in Kent-Maidstone and Tunbridge Wells.

METHODS

Patients were recruited if they attended the clinic of their own accord without a letter of referral from their GPs; a definitive or provisional diagnosis was made and the patient was managed in the clinic; the patient's GP had received a conventional reply from the GUM clinic for other patients referred in the past. Separate GP letters were developed for male and female patients. These handwritten study letters were read by the patients who took the responsibility to deliver them to their GPs. This was followed by a questionnaire to the GPs.

RESULTS

75 patients were eligible. Seven patients refused to participate. All questionnaires were returned by the GPs for the 68 participating patients (100%). Seven GPs failed to receive the study letter. For these unreferred patients, this was an improvement in communication level from 0% to 80%. 79% (95% confidence interval: 67%-87%) preferred the study letter, 97% (89%-99%) would like to receive a similar letter for future patients. All GPs thought that the study letter was at least as good as the standard letter 52% (40%-64%) thought it was better. For 82% (70%-90%) it was the preferred format for future communication.

CONCLUSION

The study has shown a way of establishing communication with GPs for patients who do not object to this. The results also suggest that in the study districts neither the GPs nor the majority of study patients had any objection to the sharing of information between the GUM clinics and GPs.

Inhomogeneities in wall stress measured by microergometry in the heart muscle in situ

Microergometry is a method which we have developed as a tool to measure local mesh-tension within the myocardial weave at any measuring site of both ventricles and the septum on the beating heart in situ. In a mapping procedure on pig and dog hearts, both in control conditions and in the hypertrophied state after aortic banding, local mesh-tension was measured in several areas and in up to eight depths proceeding from the epicardium to the endocardium: Probe-to-fibre coupling is definitely more stable in the canine myocardium than in the porcine heart muscle, probably due to a more effective connective tissue fettering of the canine myocardial weave. The observed longitudinal gradient, with the highest tension in the base, of control dog hearts was levelled out in the hypertrophied hearts. Furthermore, in control dog hearts mesh-tension in the subepi- and subendocardial layers was higher than in the midlayers. This pronounced midlayerhypotension was smoothed in the hypertrophied hearts. Further studies will be dedicated to the question of whether the impact of ventricular size and shape on intersegmental stress transmission is determined by the Frank-Starling mechanism alone or whether protracted remodelling processes on the level of the local fibre weave cause slow coupling alterations.

The heart muscle's putative "secondary structure'. Functional implications of a band-like anisotropy

Opinions are divided as to whether the rope-like secondary structure, which Torrent-Guasp dissected out of the myocardial body by the blunt unwinding technique (BUT) reveals some kind of functional compartmentation of the heart muscle. The myocardial fibres are aligned parallel to the fibre disruption (cleavage) plane, along which the band has been prepared but they are not necessarily aligned parallel to the long axis of the band. Inconsistencies in the myocardial rope model arise from the obligatory zones of transmural inflection, which are obvious in the base and the apex of both ventricles. They are, however, merely discernible in the midzone of the left ventricular cone. The investigator experienced in BUT knows that the cleavage plane is not unique. We doubt the assumption that the rope structure is the predominant stress transmission pathway, because the fibre strand peel-off technique (SPOT) delivers irregular fibre disruption planes which are definitely different from those which Torrent-Guasp prepares. The rope-like fibre arrangement could be just a redundant structure, a remnant of past developmental steps without, however, any functional implication to the human heart. On the other hand, peeling-off fibre strands from the ventricular wall produces deeply perforating, i.e., oblique transmurally grooved surfaces. Putative functions of force transmission in an oblique transmural direction are (1) ventricular dilation as a function of the variable inclination angle with respect to the epicardial surface, (2) monitoring of ventricular wall stress and ventricular size and (3) segmental stiffening which could serve other dependent segments as a punctum fixum.

The assessment of intramural stress alignment on the beating heart in situ using micro-ergometry: functional implications

The main local stress transmission pathways in the left ventricular base, midportion and apex in up to seven layers have been assessed in normal dog and porcine hearts, in hypertrophied dog hearts, and in three pig hearts having undergone a temporary left ventricular outflow stricture. The rotational sensitivity of needle force probes was used to determine the focal surface-parallel direction of the myocardial tension vector. In all places investigated the orientation of the force transmission pathways differs slightly from the morphologically determined fibre alignment. Vector rotation upon an axis normal to the epicardial surface is definitely tempered as compared to fibre rotation. Alterations in the force transmission pathways assessed in hypertrophied dog hearts by micro-ergometry qualitatively confirm structural remodelling in so far as an irregularity in the transmural rotation of the main stress vector was found. The measured disparities between the alignment of the myocardial fibre weave and the direction of stress transmission both in the normal and the diseased heart is widely individual, and hence, scattering of the data is marked. However, it must also be called into consideration that the measured orientation of force vectors is that at the moment of highest developed force, only. Further investigations will elucidate if discrepancies between that force vector and morphology are less pronounced when the vector is averaged over the entire heart cycle.

The heart's fibre alignment assessed by comparing two digitizing systems. Methodological investigation into the inclination angle towards wall thickness

Myocardial contractile pathways which are not aligned strictly parallel to the heart's epicardial surface, give rise to forces which also act in the ventricular dilating direction. We developed a method which allows us to assess any fibre orientation in the three-dimensional myocardial weave. Decollagenized hearts were prepared by peeling-off fibre strands, following their main fibre orientation down to near the endocardium. In the subepicardium the strands followed a course more or less parallel to the epicardium, whereas from the mid-wall on they tended to dive progressively deeper into the wall. The preparation displays more or less rugged surfaces rather than smooth layers. The grooves and crests on the exposed surfaces were sequentially digitized by two methods: (1) Using a magnet tablet (3 Draw Digitizer System, Polhemus, Cochester VTO 5446, USA) on a dilated pig heart we manually followed the crests using a stylus, handling each groove and crest as an individual contractile pathway. (2) A constricted cow heart was digitized using a contact-free optical system (opto TOP, Dr. Breuckmann, Meersburg, Germany), which is based on the principle of imaging triangulation. Using specially developed software the inclination angles of selected crests and grooves with respect to the epicardial surface were calculated. The two digitizing methods yield comparable results. We found a depth- and side-specific weave component inclined to the epi-endocardial direction. This oblique netting component was more pronounced in the inner 1/3 of the wall than in the subepicardium. The inclination angle probably increases with increasing wall thickness during the ejection period. Manual digitizing is an easy and fast method which delivers consistent results comparable with those obtained by the cumbersome high resolution optical method. The rationales for the assessment of transmural fibre inclination are (1) the putative existence of dilating forces inherent in the myocardial weave and (2) the possible overproportional increase in the oblique transmural weave component during myocardial hypertrophy, which would entail a reduction in efficiency of ventricular performance in terms of haemodynamic work.

Feasibility and effects of nurse run clinics for patients with epilepsy in general practice: randomised controlled trial. Epilepsy Care Evaluation Group

OBJECTIVE

To test the feasibility and effect of nurse run epilepsy clinics in primary care.

DESIGN

A randomised controlled trial of nurse run clinics versus "usual care."

SETTING

Six general practices in the South Thames region.

SUBJECTS

251 patients aged over 15 years who were taking anti-epileptic drugs or had a diagnosis of epilepsy and an attack in the past two years who met specified inclusion criteria and had responded to a questionnaire.

MAIN OUTCOME MEASURES

Questionnaire responses and recording of key variables extracted from the clinical records before and after the intervention.

RESULTS

127 patients were randomised to a nurse run clinic, of whom 106 (83%) attended. The nurse wrote 28 letters to the general practitioners suggesting changes in epilepsy management. For this intervention group compared with the usual care group there was a highly significant improvement in the level of advice recorded as having been given on drug compliance, adverse drug effects, driving, alcohol intake, and self help groups.

CONCLUSIONS

Nurse run clinics for patients with epilepsy were feasible and well attended. Such clinics can significantly improve the level of advice and drug management recorded.

The prevalence of anencephalus and spina bifida in New Zealand

Despite the plethora of epidemiological research conducted on anencephalus and spina bifida, few of the studies have used multiple source case ascertainment and controlled for the effect of possible confounding factors. This paper reports the results from a study of the relationships between various risk factors and the prevalence of anencephalus and spina bifida in New Zealand during 1978-82, using case data obtained from multiple sources and a national cohort of births as the denominator. The rates of anencephalus and spina bifida in New Zealand were 0.78/1000 and 0.94/1000 total births, respectively. The rate of a neural tube defect (NTD) birth for Maori parents was less than for their non-Maori counterparts. Paternal ethnic origin and maternal ethnic origin made similar contributions to the model of anencephalus rates, but the results suggest that paternal ethnic origin is a less important risk factor in the prevalence of spina bifida. The rate of both NTD was high among female infants and low among births to women born in countries other than the British Isles and New Zealand. The rate of anencephalus showed a distinct north-south gradient, but there was no evidence of effects for maternal or paternal age, parity, urban-rural place of residence, nuptiality, social class or season of birth in the prevalence of either NTD in New Zealand.

Fallacies of international and national comparisons of disease occurrence in the epidemiology of neural tube defects

Despite extensive research, little progress has been made in elucidating the etiologies of anencephalus and spina bifida. International and national distributions of disease occurrence have often been used as a basis for generating etiological hypotheses (e.g., potato blight, tea consumption, and zinc deficiency hypotheses). However, few of the epidemiological studies of neural tube defects (NTDs) have been conducted with scientific rigor in design, and most are of dubious validity, often with low precision in the estimates. This paper shows that the accepted geographic patterns of NTDs may be attributable to variations in the validity of studies used to describe these patterns. The nonuniformity in the duration and diligence of case ascertainment, the lack of a standardized nomenclature and classification, and the definition of the denominator remain principal problems in evaluating the epidemiology of NTDs. For example, the distinction between incidence and prevalence is not always made, and there is no consistency in the placement of the gestational boundary between late fetal deaths and spontaneous abortions. Findings are compared from studies conducted at different times, without due regard to the effect of secular trends, and using studies that have varying levels of case ascertainment. In etiological research, it is important to perform studies that are accurate and precise, but the literature used to define the spatial distribution of NTDs has often been accepted without due regard to the effect of these factors.

Mass spectrometry of beta-lactam antibiotics with special reference to ionization by fast atom bombardment (FAB)

The mass spectral characteristics of the majority of penicillin and cephalosporin beta-lactam antibiotics in world-wide clinical use are presented and reviewed. Special attention is given to the spectra recorded under fast atom bombardment (FAB) conditions and novel data on many penicillins and cephalosporins are included. Mass spectrometry features of common degradation products of benzylpenicillin and of some synthetic intermediates are also presented. The data illustrate the value of FAB mass spectrometry in identifying members of this closely related group of antibiotics without need for derivatization.

Interlaboratory standardization of enzyme results: the Richmond project

Three concentrations of proficiency monitoring material and two concentrations of secondary standard calibrating material were prepared and stored frozen. The materials were prepared in buffer containing amylase from human saliva, aspartate aminotransferase from human liver, creatine kinase from human muscle, human serum albumin (20 g/L), and cofactors. The proficiency monitoring material was assayed by 10 methods in nine laboratories for 15 days to establish baseline performance. Each laboratory then used the secondary standard calibrating material to calibrate their instruments' responses to that of a standardization method, and repeated the assay of the proficiency monitoring material for 15 days. For amylase before calibration, between-laboratory mean values for the three concentrations of proficiency monitoring material were 29% lower than the standardization method, and the between-laboratory CV was 28%. After calibration the mean amylase values were 4% lower and the CV was 6%. For aspartate aminotransferase, the pre-calibration between-laboratory mean values were 24% higher than the standardization method (CV 14%) but only 3% higher (CV 6%) after calibration. CK activity deteriorated at storage temperatures above -70 degrees C. This study demonstrates that, by using a common secondary standard, laboratories can improve calibration of enzyme results.

Interlaboratory standardization of enzyme results: the Richmond project

Three concentrations of proficiency monitoring material and two concentrations of secondary standard calibrating material were prepared and stored frozen. The materials were prepared in buffer containing amylase from human saliva, aspartate aminotransferase from human liver, creatine kinase from human muscle, human serum albumin (20 g/L), and cofactors. The proficiency monitoring material was assayed by 10 methods in nine laboratories for 15 days to establish baseline performance. Each laboratory then used the secondary standard calibrating material to calibrate their instruments' responses to that of a standardization method, and repeated the assay of the proficiency monitoring material for 15 days. For amylase before calibration, between-laboratory mean values for the three concentrations of proficiency monitoring material were 29% lower than the standardization method, and the between-laboratory CV was 28%. After calibration the mean amylase values were 4% lower and the CV was 6%. For aspartate aminotransferase, the pre-calibration between-laboratory mean values were 24% higher than the standardization method (CV 14%) but only 3% higher (CV 6%) after calibration. CK activity deteriorated at storage temperatures above -70 degrees C. This study demonstrates that, by using a common secondary standard, laboratories can improve calibration of enzyme results.