The landscape of neurophysiological outcome measures in ALS interventional trials: A systematic review

OBJECTIVE

We collated all interventional clinical trials in amyotrophic lateral sclerosis (ALS), which utilised at least one neurophysiological technique as a primary or secondary outcome measure. By identifying the strengths and limitations of these studies, we aim to guide study design in future trials.

METHODS

We conducted and reported this systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight databases were searched from inception. In total, 703 studies were retrieved for screening and eligibility assessment.

RESULTS

Dating back to 1986, 32 eligible interventional clinical trials were identified, recruiting a median of 30 patients per completed trial. The most widely employed neurophysiological techniques were electromyography, motor unit number estimation (including motor unit number index), neurophysiological index and transcranial magnetic stimulation (including resting motor threshold and short-interval intracortical inhibition). Almost 40% of trials reported a positive outcome with respect to at least one neurophysiological measure. The interventions targeted either ion channels, immune mechanisms or neuronal metabolic pathways.

CONCLUSIONS

Neurophysiology offers many promising biomarkers that can be utilised as outcome measures in interventional clinical trials in ALS. When selecting the most appropriate technique, key considerations include methodological standardisation, target engagement and logistical burden.

SIGNIFICANCE

Future trial design in ALS would benefit from a standardised, updated and easily accessible repository of neurophysiological outcome measures.

Electrodiagnostic applications of somatosensory evoked high-frequency EEG oscillations: Technical considerations

INTRODUCTION

High frequency oscillations (HFOs) embedded within the somatosensory evoked potential (SEP) are not routinely recorded/measured as part of standard clinical SEPs. However, HFOs could provide important additional diagnostic/prognostic information in various patient groups in whom SEPs are tested routinely. One area is the management of patients with hypoxic ischaemic encephalopathy (HIE) in the intensive care unit (ICU). However, the sensitivity of standard clinical SEP recording techniques for detecting HFOs is unknown.

METHODS

SEPs were recorded using routine clinical methods in 17 healthy subjects (median nerve stimulation; 0.5 ms pulse width; 5 Hz; maximum 4000 stimuli) in an unshielded laboratory. Bipolar EEG recordings were acquired (gain 50 k; bandpass 3Hz-2 kHz; sampling rate 5 kHz; non-inverting electrode 2 cm anterior to C3/C4; inverting electrode 2 cm posterior to C3/C4). Data analysis was performed in MATLAB.

RESULTS

SEP-HFOs were detected in 65% of controls using standard clinical recording techniques. In 3 controls without significant HFOs, experiments were repeated using a linear electrode array with higher spatial sampling frequency. SEP-HFOs were observed in all 3 subjects.

CONCLUSIONS

Currently standard clinical methods of recording SEPs are not sufficiently sensitive to permit the inclusion of SEP-HFOs in routine clinical diagnostic/prognostic assessments. Whilst an increase in the number/density of EEG electrodes should improve the sensitivity for detecting SEP-HFOs, this requires confirmation. By improving and standardising clinical SEP recording protocols to permit the acquisition/analysis of SEP-HFOs, it should be possible to gain important insights into the pathophysiology of neurological disorders and refine the management of conditions such as HIE.

Common toxidromes in movement disorder neurology

BACKGROUND

Physicians can come across patients who are exposed to certain prescription drugs or toxins that can result in adverse effects and complications which have high rates of morbidity and mortality.

OBJECTIVE

To summarise the key clinical features and management of the common movement disorder toxidromes relevant to physicians (with an interest in neurology).

METHODS

We searched PUBMED from 1946 to 2016 for papers relating to movement toxidromes and their treatment. The findings from those studies were then summarised and are presented here.

RESULTS

The key features of 6 of the common movement disorder toxidromes and their treatment are tabulated and highlighted. The management of toxidromes with the highest mortality like neuroleptic malignant syndrome and serotonin syndrome are discussed in detail.

CONCLUSION

There are several toxidromes that have the potential to become a serious life-threatening emergency if there is a delay in recognition of key clinical features and instituting the appropriate treatment at the earliest is crucial.

Fibroblast growth factor 2 alters the oxytocin receptor in a developmental model of anxiety-like behavior in male rat pups

We aimed to determine the short-term effects of early-life stress in the form of maternal separation (MS) on anxiety-like behavior in male rat pups. In order to assess anxiety, we measured 40kHz separation-induced ultrasonic vocalizations (USV) on postnatal day (PND) 11. We further aimed to evaluate the potential involvement of two neurochemical systems known to regulate social and anxiety-like behaviors throughout life: oxytocin (OT) and fibroblast growth factor 2 (FGF2). For these purposes, we tested the effects of neonatal administration (on PND1) of an acute dose of FGF2 on USV and its potential interaction with MS. In addition, we validated the anxiolytic effects of OT and measured oxytocin receptor (OTR) gene expression, binding and epigenetic regulation via histone acetylation. Our results show that MS potentiated USV while acute administration of OT and FGF2 attenuated them. Further, we found that both FGF2 and MS increased OTR gene expression and the association of acH3K14 with the OTR promoter in the bed nucleus of the stria terminalis (BNST). Comparable changes, though not as pronounced, were also found for the central amygdala (CeA). Our findings suggest that FGF2 may exert its anxiolytic effects in male MS rats by a compensatory increase in the acetylation of the OTR promoter to overcome reduced OT levels in the BNST.

Multi-system neurological disease is common in patients with OPA1 mutations

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal 'dominant optic atrophy plus' variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.

Non-uniform olivocerebellar conduction time in the vermis of the rat cerebellum

It has been proposed that the conduction velocities of cerebellar climbing fibre (olivocerebellar) axons are tuned according to length, in order to precisely fix the conduction time between the inferior olive and cerebellar cortex. Some data conflict with this view. We have re-evaluated this issue using the climbing fibre reflex. The white matter of the tip of one folium in lobule VI or VII was stimulated electrically 0.5-1 mm below the surface and recordings were made from Purkinje cells in lobules VIII and IX. Reflex evoked climbing fibre (CF) responses (33 units) were recorded at different depths from Purkinje cells found in a narrow sagittal zone of cortex as complex spikes. The responses had latencies ranging from 4.3 ms to 11.3 ms. A consistent trend was that Purkinje cell responses recorded at greater depth had shorter CF reflex latencies than those recorded more superficially, both in individual experiments and in grouped data. These data show that the CF reflex latency is not constant, but is directly proportional to the distance an action potential has to travel along a CF. These data are not consistent with tuning of CF conduction velocities to normalize olivocerebellar conduction time, but are consistent with a CF conduction velocity in the cortex of approximately 0.6 m s-1. This suggests that climbing fibres projecting to different parts of the cerebellar cortex may have differences in spike conduction time of a few milliseconds, and that submillisecond precision is not an important element of the climbing fibre signal.

Treatment of stiff person syndrome with rituximab

This case report is about the novel use of the anti-CD20 antibody, rituximab, in the treatment of a 41 year old woman with stiff person syndrome. She was admitted to hospital as an emergency with prolonged and painful extensor spasms affecting the neck and back, arms, and legs. The disease had progressed despite a favourable initial response to conventional treatment with intravenous immunoglobulin and cytotoxics. Treatment with rituximab induced a lasting clinical remission.

Structure of the voltage-gated L-type Ca2+ channel by electron cryomicroscopy

Voltage-dependent L-type Ca(2+) channels play important functional roles in many excitable cells. We present a three-dimensional structure of an L-type Ca(2+) channel. Electron cryomicroscopy in conjunction with single-particle processing was used to determine a 30-A resolution structure of the channel protein. The asymmetrical channel structure consists of two major regions: a heart-shaped region connected at its widest end with a handle-shaped region. A molecular model is proposed for the arrangement of this skeletal muscle L-type Ca(2+) channel structure with respect to the sarcoplasmic reticulum Ca(2+)-release channel, the physical partner of the L-type channel for signal transduction during the excitation-contraction coupling in muscle.

Activation of cerebellar climbing fibres to rat cerebellar posterior lobe from motor cortical output pathways

1. The activation of climbing fibres projecting to the posterior lobe cerebellar cortex by focal stimulation of the cerebral corticofugal pathway was investigated in anaesthetised rats. Large climbing fibre responses were evoked in parts of crus II and paramedian lobule by stimulation of corticofugal fibres. Lesions of the pyramidal tract just rostral to the inferior olive substantially reduced these responses, suggesting that they were not mediated by relays in the rostral brainstem. 2. By comparison of latencies of climbing fibre responses evoked from different locations in the corticofugal pathway, the conduction velocities of the corticofugal fibres that mediate the responses were estimated to be 1.9 +/- 0.3 m s(-1) (mean +/- S.E.M.). The fastest conducting corticofugal fibres were estimated to conduct significantly faster (18.7 +/- 2.3 m s(-1)). 3. Climbing fibre responses with similar form and cerebellar distribution were evoked from sites in the pyramidal tract rostral and caudal to the inferior olive. This suggests that at least a proportion of the fibres that activate climbing fibres are corticospinal fibres. 4. Lesions of the dorsal column nuclei did not affect the climbing fibre responses evoked in crus II, and produced a relatively small reduction of the responses in the paramedian lobule. This implies that the climbing fibre responses were not exclusively mediated via the dorsal column nuclei. 5. Corticofugal evoked climbing fibre responses were mapped across the cerebellar hemisphere. At some sites they were co-localised with responses evoked by limb afferents. On the basis of limb afferent inputs and other work, these zones were tentatively identified as being functionally equivalent to the c1, c2 and d zones described in the cat.

Does Inverting Text Improve Reading Performance in Homonymous Hemianopes?

Anecdotal information from rehabilitation practice of reading performance and low-vision practice suggests that where right homonymous parafoveal field loss impairs reading at the visual-sensory level, an improvement in reading speed can be achieved by inverting the text. This is because whilst left-field loss is considered to impair return eye movements to the beginning of a line, right-field loss is considered to reduce the spatial size of the perceptual window and increase its temporal extent by prolonging fixations times, reducing the amplitudes of saccades to the right, and introducing frequent regressive saccades. Inverting the text was thought to reverse these effects as the leading edge of the perceptual window is ‘returned’ to the sighted field so that in-line saccades can be visually guided.

Here we report that this does not appear to be the case. In our study we measured the eye movements of patients with right homonymous hemianopia and others with peripheral loss due to retinitis pigmentosa as well as normal controls using an infrared video eye-tracker. All groups display a similar proportional prolongation of fixations times, reduction of saccadic amplitude, and proportion of regressive saccades when asked to read inverted text, which suggests a cognitive component of impairment independent of visual field loss in right homonymous hemianopes.

Ultrasonographic detection of testicular ischemia in a canine model using phospholipid coated microbubbles (MRX-115)

The purpose of this study was to determine if the sonographic contrast agent MRX-115 could improve the accuracy of Doppler ultrasonographic diagnosis of testicular ischemia. Testicular duplex ultrasonography was performed on six dogs before and after surgical ligation of the testicular artery, and before and after intravenous injection of MRX-115. Six radiologists blinded to experimental conditions rated the testicular blood flow. Receiver operating characteristics curves for conditions with and without administration of contrast agent were compared using Student's t-test for paired observations. Statistically significant differences were found both for the tests viewed individually (P = 0.003) and for the testes in comparison to the contralateral side (P = 0.0001). MRX-115 therefore is found to improve duplex sonographic evaluation of testicular ischemia.

Popliteal vascular compression in a normal population

PURPOSE

Positional popliteal artery obstruction is believed to be an important factor contributing to popliteal artery entrapment syndromes. This study was undertaken to define the positional anatomy and physiologic condition of the vessels in the popliteal fossa in groups of highly trained and normally active young men and women. We postulate that at least some symptom-free individuals can occlude the popliteal artery with leg positioning.

METHODS

Seventy-two limbs were evaluated in 36 subjects. Symptom-free subjects were recruited in four groups: normally active men, normally active women, male competitive runners, and female competitive runners. All subjects underwent noninvasive testing that included resting segmental limb pressures and Doppler waveforms and color-flow duplex imaging with the leg in the neutral position and then with knee extension with active and passive dorsiflexion and plantar flexion of the foot. Subjects unable to occlude the popliteal artery with positioning were then exercised, and studies were repeated. Magnetic resonance imaging, with magnetic resonance angiography, was conducted on 14 subjects, with each leg studied in the neutral position and with active positioning.

RESULTS

Positional popliteal arterial occlusion occurred in 38 of 72 limbs (53%). No intergroup comparisons were statistically significant. The response of each leg was symmetric in 89% of subjects. No subject who could not occlude the popliteal artery at rest was able to do so with exercise. Magnetic resonance imaging disclosed normal anatomy in all subjects and showed the location of popliteal occlusion to be at the level of the soleal sling, with positional compression by the soleus muscle, the lateral head of the gastrocnemius, the plantaris, and popliteus muscles.

CONCLUSION

Popliteal arterial occlusion can be induced in 53% of subjects with simple leg positioning caused by myofascial compression. This must be considered when evaluating patients for intervention on the basis of physiologic testing of the popliteal vessels.

Cardiac tamponade and recurrent upper respiratory tract infections in a 22-year-old woman

The association of IgA deficiency with SLE is clearly established but occurs in only a small percentage of patients. Several hypotheses address the relationship between the two disease processes but the common link remains undetermined. It is important to investigate the diagnosis of IgA deficiency in patients presenting with SLE in order to provide the most appropriate treatment. This patient not only represents a rare presentation of SLE but highlights the uncommon occurrence with IgA deficiency and brings forth valuable teaching points of both diseases.

Magnetic resonance imaging in systemic lupus erythematosus patients without a history of neuropsychiatric lupus erythematosus

OBJECTIVE

To determine the prevalence of magnetic resonance imaging (MRI) lesions in systemic lupus erythematosus (SLE) patients without a history of neuropsychiatric symptoms and to correlate any MRI abnormalities with the patient's other disease manifestations or treatment.

METHODS

Prospective study of 32 consecutive patients with SLE without a history of neuropsychiatric symptoms, from inpatient and outpatient rheumatology services, who underwent MRI scan during a 3-year period.

RESULTS

Five patients had MRI abnormalities consisting of white matter lesions or periventricular hyperintensities; this is similar to the prevalence of these abnormalities in the general population.

CONCLUSION

The prevalence of silent brain MRI abnormalities is not increased in SLE patients who do not have a history of neuropsychiatric manifestations.

Sacral insufficiency fractures in rheumatoid arthritis

METHODS

All patients with rheumatoid arthritis (RA) attending an outpatient rheumatology clinic at a major military medical center over 6 years were included in follow-up for the development and subsequent course of sacral insufficiency fractures.

RESULTS

Sacral insufficiency fractures developed in 4 of 386 patients. Consistent with the literature, patients were female, elderly, and/or postmenopausal, had severe or long-standing disease, and were taking corticosteroids. The correct diagnosis was initially delayed because radiographs were normal but was later established with bone scan and sacral computerized tomography. Each patient improved with calcitonin and/or physical therapy over time.

CONCLUSIONS

Patients with RA represent a unique subgroup predisposed to insufficiency fractures because of multiple osteoporotic risk factors. Patients who have RA and acute low back or buttock pain should be evaluated aggressively for sacral insufficiency fractures with bone and/or computed tomography scans regardless of normal plain radiographs.

In-111 CYT-103 immunoscintigraphy in the imaging of ovarian carcinoma

Fifteen presurgical patients with a history of ovarian carcinoma were evaluated with immunoscintigraphy using the In-111-labeled monoclonal antibody conjugate CYT-103. Twelve of these patients had residual neoplasia at time of laparotomy. A single intravenous dose of the radiolabeled monoclonal antibody was given to these patients before restaging laparotomy. All patients also underwent CT scanning of the abdomen and pelvis before laparotomy. Immunoscintigraphy detected the presence of disease in 10 of 12 patients before surgery, whereas CT scanning detected disease in only 6 of these 12 women. The results of this study indicate that immunoscintigraphy using In-111 CYT-103 is more sensitive than CT and may add useful information to the preoperative evaluation of women with ovarian carcinoma.

Ethnic differences in risk markers for heart disease in Bradford and implications for preventive strategies

OBJECTIVES

To assess and compare the prevalence of established risk markers for ischaemic heart disease in a sample of Asian and non-Asian men and to relate these observations to preventive strategies.

SETTING

Two factories in the textile industry in Bradford, West Yorkshire, UK. Subjects--288 male manual workers aged 20 to 65 years.

DESIGN

Cross sectional study within one occupational/social class stratum.

MEASUREMENTS AND MAIN RESULTS

Age, body mass index, plasma lipids, fibrinogen and serum insulin values, blood pressure, smoking habits, alcohol consumption, and exercise routines were recorded. Plasma total cholesterol concentrations were significantly lower in Asian than non-Asian men (5.3 mmol/l v 5.8 mmol/l respectively, p < 0.0001), as were low density lipoprotein cholesterol concentrations (3.4 mmol/l v 3.7 mmol/l, p = 0.0150), and high density lipoprotein (HDL) cholesterol (1.1 mmol/l v 1.3 mmol/l, p < 0.0001). Hypercholesterolaemia (concentration > 6.5mM) was present in nearly one quarter of non-Asians but less than one eighth of Asian men. Triglyceride values were not significantly higher in Asians. Smoking rates were high in non-Asians (43.8%) and only slightly lower in Asians (39.1%). Asian smokers smoked fewer cigarettes per day on average (9.3 v 16.1, p = 0.0001). Almost a quarter of non-Asian men (23.1%) and 26.6% of Asian men had raised blood pressure. Systolic pressures were higher in non-Asian men (138.3 mmHg v 133.0 mmHg, p = 0.0070), but diastolic pressures showed no ethnic differences. Diabetes was more prevalent in Asian men (10.9% v 4.4% p < 0.05), who also showed higher serum insulin concentrations after glucose loading (22.3 mU/l v 10.2 mU/l, p < 0.0001). Plasma fibrinogen values were higher in non-Asian men (2.9 g/l v 2.6 g/l, p < 0.0001) and these were associated with smoking. Nearly all non-Asians (92.5%) consumed alcohol at some time whereas 62.5% of Asians habitually abstained from alcohol consumption. Among the drinkers, non-Asian men consumed on average, 23.9 units per week and Asian men 18.4 units per week (p = 0.083). The mean body mass index for Asian men was 24.5 kg/m2 which was not significantly different to the mean in non-Asian men (25.2 kg/m2). The frequency of exercise in leisure time was low in both groups with 44.4% of non-Asian and 21.1% of Asian men taking moderate exercise weekly, and even fewer, regular strenuous exercise (16.3% and 8.6% respectively).

CONCLUSIONS

The plasma cholesterol and fibrinogen concentrations, prevalence of hypertension, smoking habits, alcohol intakes, and infrequency of exercise in leisure time in these non-Asian men in Bradford were consistent with an increased risk of heart disease. The pattern of risk markers was clearly different in Asian men. Only their lower HDL cholesterol concentrations, marginally higher triglyceride values, higher prevalence of diabetes, and very low frequency of exercise in leisure time would be consistent with a higher risk of heart disease compared with non-Asians. The implications of these observations for heart disease preventive strategies are discussed.

Insulin resistance, diabetes, and risk markers for ischaemic heart disease in Asian men and non-Asian in Bradford

OBJECTIVE

To examine the hypothesis, in a community not studied before, that insulin resistance associated with centralised adiposity is the mechanism underlying the predisposition of Asian immigrant communities to both ischaemic heart disease and diabetes mellitus.

DESIGN

Cross sectional study within one socioeconomic stratum.

SETTING

Two factories in the textile sector in Bradford, West Yorkshire.

SUBJECTS

Male manual workers of Asian (110) and non-Asian origin (156) aged 20-65 years.

RESULTS

Diabetes was almost three times more prevalent in the Asian group. Two hours after an oral glucose load Asian men had double the serum insulin concentrations of non-Asian men (p < 0.0001). Asian men also had significantly lower concentrations of plasma total cholesterol (p < 0.03), high density lipoprotein cholesterol (HDL) (HDL2, p < 0.0001; HDL3, p < 0.0001), and apolipoprotein AI (p < 0.0001). Fasting plasma triglyceride concentrations were slightly higher (p = 0.072) in the Asian men; thus the ratio of triglyceride cholesterol was higher (p = 0.006). The inter-relation between serum insulin and plasma lipid concentrations indicated metabolic differences between the ethnic groups. Insulin concentrations were associated with cholesterol concentrations in the Asian men only and there was a lack of association between triglyceride, low density lipoprotein cholesterol, and HDL cholesterol in this group. The risk marker profile in the Asian men was therefore quite different to that of their non-Asian counterparts and was associated with a greater tendency to centralised adiposity.

CONCLUSION

These data support the insulin resistance hypothesis and thus have important implications for strategies for the prevention of heart disease in Asian communities in the United Kingdom.

Role of the medical director

The regulations establishing NHS trusts make specific provision for a medical director on the board of every trust, although no guidance is issued on the responsibilities associated with such a post. This paper explores the possible roles and relationships facing the medical director.

The effect of tensile strength on the clinical effectiveness and patient acceptance of dental floss

This study compared the clinical effectiveness and subjective approval of 2 waxed dental flosses that differed significantly in tensile strength and wax content. At the initial appointment, subjects (20 1st-year dental students) were instructed to stop interproximal cleaning on 2 contralateral quadrants in order to allow plaque to accumulate on these surfaces for 1 week. 1 week later, subjects were instructed to begin flossing these 2 contralateral quadrants with 1 of the 2 types of floss for the next 1-week period, while withdrawing interproximal cleaning on the opposite 2 contralateral quadrants. After flossing these 2 quadrants for 1 week, the subjects began flossing the opposite 2 contralateral quadrants with the same floss. After 2 weeks of flossing contralateral quadrants, the 1st floss was withdrawn and replaced with the alternative floss for another similar 2-week trial period. At the end of each 2-week trial period, subjects completed subjective questionnaires concerning the floss they had used during the previous 2-week period. Pre- and post-flossing plaque indices were calculated for each week for both flosses, and compared statistically by a repeated measures analysis of variance. The results showed that both flosses significantly reduced interproximal plaque deposits, and had equal subjective approval. However, neither the greater-strength nor the lower-wax content of the experimental floss was associated with an increase in clinical effectiveness or with a change in subjective approval.

Immunoscintigraphy of colorectal carcinoma utilizing 111In-labeled monoclonal antibody conjugate CYT-103

Twelve presurgical patients with colorectal carcinoma received a single intravenous infusion of 0.5-20.0 mg of the radiolabeled monoclonal antibody conjugate CYT-103. This product is an immunoconjugate of B72.3 labeled with Indium-111 (111In). Patients underwent preoperative gamma camera imaging and computed tomographic (CT) scanning of the abdomen and pelvis. Fifteen intraabdominal sites of tumor were found at surgery. Monoclonal antibody imaging detected 87% of these lesions, whereas CT of the abdomen and pelvis detected 47%. Monoclonal antibody imaging identified tumor in 27% of the patients in which CT did not identify any sites of tumor. The results of this study indicate that monoclonal antibody imaging using [111In]CYT-103 is useful for the preoperative evaluation of colorectal carcinoma patients and the results are complimentary to CT of the abdomen and the pelvis.

Patients' choice of general practitioner: importance of patients' and doctors' sex and ethnicity

The relative importance of sex and ethnicity in patients' choice of doctor is not known. A total of 1633 consultations at a health centre in Bradford, with a mixed ethnic list, were examined over a four week period to test the relative importance of these variables. Patients had the choice to consult any one of: a male Asian, a male white or a female white doctor. Asian patients, irrespective of sex, were significantly (P less than 0.001) more likely to consult the Asian doctor then either of the other two doctors, though a greater proportion of Asian women than men consulted the female white doctor. Although the sex of the doctor was important in patients' choice, for Asian patients the doctor's culture and language were more important.

General practitioners' perceptions of Asian and non-Asian patients

The literature on the health of the population of Asian origin contains little on their interaction with primary care services. This paper reports results of a postal survey of GPs' attitudes towards Asian and Non-Asian patients. The response rate was 78%-141 of the 182 GPs replied. Compared with non-Asian patients, GPs held less positive attitudes towards Asian origin patients who were thought to require longer for consultations, be less compliant, and make excessive and inappropriate use of health services. These perceptions have implications for patient care and the GP workload.

Incidence of cancer in Bradford Asians

STUDY OBJECTIVE

The aim of the study was to investigate the incidence of cancer in Asians living in Bradford.

DESIGN

Cancer registrations were obtained from the Yorkshire Regional Cancer Registry for the six year period 1979-1984. Registrations relating to persons of Asian background were extracted using forenames and surnames. Data were analysed by disease category and age and sex specific incidence rates were calculated. These were compared with expected incidence rates for the non-Asian population and with rates for the Indian subcontinent derived from the Bombay Cancer Registry.

SETTING

Data collection was confined to the Bradford Metropolitan District, population 449,897 (1981).

SUBJECTS

The Asians studied originated from Pakistan (65%), India (28%), Bangladesh (4%), and East Africa (3%). The total Asian population of the Bradford Metropolitan District was approximately 45,000.

MAIN RESULTS

Over the study period there were 178 Asian cancer registrations. The overall standardised registration ratio was 53.7 for males (100 cases, 95% confidence interval 43-64), and 43.5 for females (78 cases, 95% CI 34-53). The standardised registration ratios for cancer of the hypopharynx in males and gall bladder in females were significantly raised. There was a particularly low incidence of cancer of the stomach, large bowel, lung, skin, and bladder in males, and of skin, breast, cervix (in situ), and ovary in females. The analyses suggested that lung and breast cancer incidence may be increasing towards the non-Asian level. In situ cancer of cervix in Asians shows no evidence of the high rates found in younger non-Asian age groups.

CONCLUSIONS

Lower incidence of many cancers in Asians may be due to lower exposure to major risk factors. Demographic change resulting in increased exposure to these risk factors can be expected to result in an increase in cancer incidence in Asians.

Optimization of low-osmolality contrast media for cranial CT: a dose comparison of two contrast agents

A prospective, randomized, double-blind comparative study of 200 patients was made to examine the image quality, safety, and costs of 100 ml of ioversol-320 (32 g iodine) and 150 ml of iohexol-300 (45 g iodine) in patients undergoing cranial CT. We found no statistically significant difference in image quality between the two low-osmolality, nonionic contrast agents at these doses. There was a statistically significant (p = .02) difference in the occurrence of minor to mild adverse effects caused by ioversol (n = 0) as compared with iohexol (n = 5). No patient in either group experienced any major contrast-induced reactions. Contrast media costs were 34% less in patients receiving 32 g of iodine as compared with those receiving 45 g of iodine. This study demonstrates that high-quality cranial CT scans are possible even with a reduced volume of low-osmolality contrast medium, and that the potential cost savings are significant.

Cross-cultural use of socio-medical indicators with British Asians

Socio-medical measures of health are increasingly being used as adjuncts to traditional clinical and epidemiological investigations. Such instruments can potentially make a significant contribution to research on inequalities in health between different ethnic groups and in planning health service delivery. However, care must be taken to ensure that the cross-cultural adaptation has conceptual, semantic and linguistic equivalence with the original and cultural differences in the meanings of health and illness must be closely considered. The use of some such instruments with Britain's Asian populations is reviewed and issues in adapting the Nottingham Health Profile for use with these populations, and some preliminary results are discussed.

The effects of single doses of X rays on the mechanical properties of pig skin in vivo

Changes in the mechanical properties of pig skin have been studied in vivo, using a dermal extensometer, after irradiation with a single dose of 18 Gy of X rays. There was no significant change in the stiffness of irradiated skin, when compared with unirradiated skin, until 9 weeks after irradiation when the irradiated skin was significantly stiffer. This effect was also found at 12 and 15 weeks after irradiation. When the increase in skin thickness, as a consequence of oedema, was taken into account a significant increase in the unrelaxed elastic modulus of irradiated skin was only seen at 12 and 15 weeks after irradiation. There were no significant changes in force relaxation, after extension of the skin, over this time period. After the resolution of oedema, which was associated with a significant 20% reduction in the thickness of irradiated skin relative to unirradiated skin, the mechanical properties of irradiated skin were not markedly different from those of unirradiated skin. However, between 30 and 39 weeks after irradiation there was a further wave of dermal thinning, resulting in a total reduction in the thickness of irradiated skin relative to unirradiated skin of 26%. This was associated with a rapid rise in the skin stiffness and unrelaxed elastic modulus by approximately 65 and approximately 140%, respectively. It was only at these late times after irradiation that the force relaxation of the skin was modified significantly. At 9 and 12 weeks after irradiation the reduction in skin stiffness and the unrelaxed elastic modulus were dose related. Based on the percentage of fields showing a significant reduction in these biomechanical parameters, ED50 values of between 12 and 14.5 Gy were established. This would appear to be a sensitive method for assessing radiation-induced dermal changes since few gross changes are observed in this dose range.

Influence of ethnicity and unemployment on the perceived health of a sample of general practice attenders

Published research shows people of Asian origin to be less healthy than the white population. Most of the studies have not taken account of differences in employment between populations of white and Asian origin. Also, little research has been carried out on the patients' perceived health. This study, based on 215 patients from an inner-city general practice in Bradford, looks at the influence of ethnicity and unemployment on the perceived health of the sample. The Nottingham Health Profile was used as the measure of perceived health. In the study population, twice as many Asians as white people were unemployed, and significant differences in perceived health were observed between the employed and the unemployed. After controlling for employment, Asian males had significantly better perceived health than white males in the 16-34 age group. Perceived health of Asian and white females was similar on most morbidity dimensions.

Patients' choice of general practitioner: influence of patients' fluency in English and the ethnicity and sex of the doctor

Asian patients' use of general practitioner services and, in particular, their interaction with doctors is not well researched. However, difficulty in communication and in the case of women, reluctance to be examined by a male doctor has been reported. This study, based on interviews with 241 Caucasian, Pakistani and Indian patients attending a general practice in Bradford, examined the relationship between choice of general practitioner and the patient's fluency in English and the general practitioner's ethnicity and sex. Both Pakistani and Indian patients, particularly women, had poor fluency in English and the use of interpreters was confined to women (11% of Pakistani women and 4% of Indian women). The linguistic and broad cultural concordance between the patient and the general practitioner was more important in the choice of doctor than the sex of the general practitioner. It was also found that while 62% of Pakistani women objected to being examined by a male doctor, this was true for only 21% of Indian women.

Health of British Asians; a research review

About 2.5 per cent of United Kingdom residents are of Asian (or Indian subcontinent) origin though the term 'Asian' hides their internal diversities of languages, religions and national origins. The research on the health of these populations is heavily concentrated in areas of rickets and osteomalacia, tuberculosis, maternal and child health, and mental health, and is mainly dependent on analysis of routinely available morbidity and mortality data. Little has been published on the use of primary care services, racism in health service delivery, quality of care and doctor-patient communication. Also, few of the studies have attempted to interpret their findings against the disadvantaged background of Asian communities. It is implied that differences in health status are due to linguistic and cultural factors alone. The research literature on the health of Asian populations is critically reviewed.

A prospective trial of the effect of vitamin D supplementation on metacarpal bone loss in elderly women

The effect on cortical bone loss of treating elderly women with 15,000 IU vitamin D2 weekly was evaluated by sequential radiographic morphometry of the metacarpals. One hundred nine randomly selected women aged 65-74 yr were studied for 2 yr. The women were randomly allocated to control or treated groups taking placebo or vitamin D2 capsules. Hand radiographs and blood samples were obtained at the beginning and end of the trial. Plasma 25-hydroxyvitamin D was measured by radio-competitive protein binding assay. Comparing the treated and control groups, vitamin D treatment significantly raised the plasma 25-hydroxyvitamin D levels (p less than 0.001) and reduced the rate of cortical bone loss (p less than 0.01). The placebo had no measurable effect on the plasma levels.