Staphylococcus aureus enterotoxin-specific IgE is associated with asthma in the general population: a GA(2)LEN study

BACKGROUND

Specific IgE to Staphylococcus aureus enterotoxins (SE-IgE) has been associated with asthma. In the general population, we aimed to determine the prevalence of and risk factors for serum SE-IgE and to examine the association with asthma.

METHODS

A postal questionnaire was sent to a random sample of adults in 19 centers across Europe. A random sample of respondents was invited for clinical examination upon which they answered a questionnaire, underwent skin prick tests (SPTs) for common aeroallergens, and provided blood for measurement of total IgE and SE-IgE. Risks were analyzed within centers using weighted logistic regression, and overall estimates calculated using fixed-effects meta-analysis.

RESULTS

2908 subjects were included in this analysis. Prevalence of positive SE-IgE was 29.3%; no significant geographic variation was observed. In contrast to positive skin prick tests, SE-IgE was more common in smokers (<15 pack-year: OR 1.11, P = 0.079, ≥15 pack-year: OR 1.70, P < 0.001), and prevalence did not decrease in older age-groups or in those with many siblings. Total IgE concentrations were higher in those with positive SE-IgE than in those with positive SPT. SE-IgE was associated with asthma (OR 2.10, 95% confidence interval [1.60-2.76], P = 0.001) in a concentration-dependent manner. This effect was independent of SPT result and homogeneous across all centers.

CONCLUSIONS

We report for the first time that SE-IgE is common in the general population throughout Europe and that its risk factors differ from those of IgE against aeroallergens. This is the first study to show that SE-IgE is significantly and independently associated with asthma in the general population.

Asthma in adults and its association with chronic rhinosinusitis: the GA2LEN survey in Europe

BACKGROUND

  The prevalence of asthma and its association with chronic rhinosinusitis (CRS) have not been widely studied in population-based epidemiological surveys.

METHODS

  The Global Allergy and Asthma Network of Excellence (GA(2) LEN) conducted a postal questionnaire in representative samples of adults living in Europe to assess the presence of asthma and CRS defined by the European Position Paper on Rhinosinusitis and Nasal Polyps. The prevalence of self-reported current asthma by age group was determined. The association of asthma with CRS in each participating centre was assessed using logistic regression analyses, controlling for age, sex and smoking, and the effect estimates were combined using standard methods of meta-analysis.

RESULTS

  Over 52,000 adults aged 18-75 years and living in 19 centres in 12 countries took part. In most centres, and overall, the reported prevalence of asthma was lower in older adults (adjusted OR for 65-74 years compared with 15-24 years: 0.72; 95% CI: 0.63-0.81). In all centres, there was a strong association of asthma with CRS (adjusted OR: 3.47; 95% CI: 3.20-3.76) at all ages. The association with asthma was stronger in those reporting both CRS and allergic rhinitis (adjusted OR: 11.85; 95% CI: 10.57-13.17). CRS in the absence of nasal allergies was positively associated with late-onset asthma.

CONCLUSION

  Geographical variation in the prevalence of self-reported asthma was observed across Europe, but overall, self-reported asthma was more common in young adults, women and smokers. In all age groups, men and women, and irrespective of smoking behaviour, asthma was also associated with CRS.

Signalling of DNA damage and cytokines across cell barriers exposed to nanoparticles depends on barrier thickness

The use of nanoparticles in medicine is ever increasing, and it is important to understand their targeted and non-targeted effects. We have previously shown that nanoparticles can cause DNA damage to cells cultured below a cellular barrier without crossing this barrier. Here, we show that this indirect DNA damage depends on the thickness of the cellular barrier, and it is mediated by signalling through gap junction proteins following the generation of mitochondrial free radicals. Indirect damage was seen across both trophoblast and corneal barriers. Signalling, including cytokine release, occurred only across bilayer and multilayer barriers, but not across monolayer barriers. Indirect toxicity was also observed in mice and using ex vivo explants of the human placenta. If the importance of barrier thickness in signalling is a general feature for all types of barriers, our results may offer a principle with which to limit the adverse effects of nanoparticle exposure and offer new therapeutic approaches.

Effects of hTERT on genomic instability caused by either metal or radiation or combined exposure

Genomic instability is considered to be an important component in carcinogenesis. It can be caused by low-dose exposure to agents, which appear to act through induction of stress-response pathways related to oxidative stress. These agents have been studied mostly in the radiation field but evidence is accumulating that chemicals, especially heavy metals such as Cr (VI), can also act in the same manner. Previous work showed that metal ions could initiate long-term genomic instability in human primary fibroblasts and this phenomenon was regulated by telomerase. The aim of this study was to examine the difference in clonogenic survival and cytogenetic damage after exposure to Cr (VI) and radiation both singly and in combination in normal human fibroblasts (hTERT- cells) and engineered human fibroblasts, infected with a retrovirus carrying a cDNA encoding hTERT, which rendered these cells telomerase positive and replicatively immortal (hTERT+ cells). Cr (VI) induced genomic instability in hTERT- cells but not in hTERT+ cells, whereas radiation induced genomic instability in hTERT+ cells and to a lesser extent in hTERT- cells. Combined exposure caused genomic instability in both types of cells. However, this genomic instability was more pronounced in hTERT- cells after radiation followed by Cr (VI) and more pronounced in hTERT+ cells after Cr (VI) followed by radiation. Moreover, the biological effects provoked by combined exposure of Cr (VI) and radiation also led to a synergistic action in both types of cells, compared to either Cr (VI) treatment only or radiation exposure only. This study suggests that telomerase can prevent genomic instability caused by Cr (VI), but not by radiation. Furthermore, genomic instability may be prevented by telomerase when cells are exposed to radiation and then Cr (VI) but not after exposure to Cr (VI) and then radiation.

Macrophages detoxify the genotoxic and cytotoxic effects of surgical cobalt chrome alloy particles but not quartz particles on human cells in vitro

Particles of surgical cobalt chrome alloy are cytotoxic and genotoxic to human fibroblasts in vitro. In vivo orthopaedic patients are exposed to cobalt chrome particles as a result of wear of a joint replacement. Many of the wear debris particles that are produced are phagocytosed by macrophages that accumulate at the site of the worn implant and are disseminated to local and distant lymph nodes the liver and the spleen. In this study we have tested whether this process of phagocytosis could have altered the cytotoxic and genotoxic properties of the cobalt chrome particles. Quartz particles have been investigated as a control. Micron-sized particles of cobalt chrome alloy were internalised by either white cells of peripheral blood or by THP-1 monocytes for 1 week and 1 day, respectively. The particles were then extracted and presented at different doses to fibroblasts for 1 day. There was a reduction of the cytotoxicity and genotoxicity of the cobalt chrome particles after phagocytosis by white cells or THP-1 cells. Cobalt chrome particles that were internalised by fibroblasts also showed a reduction of their cytotoxicity but not their genotoxicity. In contrast the cytotoxicity and genotoxicity of quartz particles was increased after internalisation by THP-1 cells. The surface morphology of the cobalt chrome particles but not the quartz particles was changed after phagocytosis by THP-1 cells. This study suggests that the genotoxic and cytotoxic properties of particles that fall within the size range for phagocytosis may be highly complex in vivo and depend on the combination of material type and previous phagocytosis. These results may have relevance for particle exposure from orthopaedic implants and from environmental or industrial pollution.

The effect of nano- and micron-sized particles of cobalt–chromium alloy on human fibroblasts in vitro

Wear debris from metal on polyethylene joint replacements causes asceptic loosening as a result of an inflammatory reaction of macrophages to micron-sized particles. Metal on metal implants, which generate nanoparticles, have been reintroduced into surgical practise in order to avoid this problem. There is a current concern about possible long-term effects of exposure to metal particles. In this study, the cytotoxic and genotoxic effects of nanoparticles and micron-sized particles of cobalt chrome alloy have been compared using human fibroblasts in tissue culture. Nanoparticles, which caused more free radicals in an acellular environment, induced more DNA damage than micron-sized particles using the alkaline comet assay. They induced more aneuploidy and more cytotoxicity at equivalent volumetric dose. Nanoparticles appeared to disintegrate within the cells faster than microparticles with the creation of electron dense deposits in the cell, which were enriched in cobalt. The mechanism of cell damage appears to be different after exposure to nanoparticles and microparticles. The concept of nanotoxicology is, therefore, an important consideration in the design of future surgical devices.

Effects of hTERT on metal ion-induced genomic instability

There is currently a great interest in delayed chromosomal and other damaging effects of low-dose exposure to a variety of pollutants which appear collectively to act through induction of stress-response pathways related to oxidative stress and ageing. These have been studied mostly in the radiation field but evidence is accumulating that the mechanisms can also be triggered by chemicals, especially heavy metals. Humans are exposed to metals, including chromium (Cr) (VI) and vanadium (V) (V), from the environment, industry and surgical implants. Thus, the impact of low-dose stress responses may be larger than expected from individual toxicity projections. In this study, a short (24 h) exposure of human fibroblasts to low doses of Cr (VI) and V (V) caused both acute chromosome damage and genomic instability in the progeny of exposed cells for at least 30 days after exposure. Acutely, Cr (VI) caused chromatid breaks without aneuploidy while V (V) caused aneuploidy without chromatid breaks. The longer-term genomic instability was similar but depended on hTERT positivity. In telomerase-negative hTERT- cells, Cr (VI) and V (V) caused a long lasting and transmissible induction of dicentric chromosomes, nucleoplasmic bridges, micronuclei and aneuploidy. There was also a long term and transmissible reduction of clonogenic survival, with an increased beta-galactosidase staining and apoptosis. This instability was not present in telomerase-positive hTERT+ cells. In contrast, in hTERT+ cells the metals caused a persistent induction of tetraploidy, which was not noted in hTERT- cells. The growth and survival of both metal-exposed hTERT+ and hTERT- cells differed if they were cultured at subconfluent levels or plated out as colonies. Genomic instability is considered to be a driving force towards cancer. This study suggests that the type of genomic instability in human cells may depend critically on whether they are telomerase-positive or -negative and that their sensitivities to metals could depend on whether they are clustered or diffuse.

Metal-specific differences in levels of DNA damage caused by synovial fluid recovered at revision arthroplasty

Previous research has shown an increase in chromosomal aberrations in patients with worn implants. The type of aberration depended on the type of metal alloy in the prosthesis. We have investigated the metal-specific difference in the level of DNA damage (DNA stand breaks and alkali labile sites) induced by culturing human fibroblasts in synovial fluid retrieved at revision arthroplasty.

All six samples from revision cobalt-chromium metal-on-metal and four of six samples from cobalt-chromium metal-on-polyethylene prostheses caused DNA damage. By contrast, none of six samples from revision stainless-steel metal-on-polyethylene prostheses caused significant damage. Samples of cobalt-chromium alloy left to corrode in phosphate-buffered saline also caused DNA damage and this depended on a synergistic effect between the cobalt and chromium ions.

Our results further emphasise that epidemiological studies of orthopaedic implants should take account of the type of metal alloy used.

Initial management of cerebrovascular disease by general practitioners

Background

The aim of this study was to determine the primary management of patients presenting with a new diagnosis of transient ischaemic attack (TIA) or stroke by general practitioners and to establish whether practice was uniform across the UK, and to determine whether initial management influenced the performance of carotid endarterectomy (CEA) across the health regions of the UK.

Methods

Information on regional reporting of new cases of TIA and stroke between 1992 and 1996 was obtained from the General Practice Research Database, a database of six million patients from 450 practices. Analysis of data from the primary care database and routine data sources was undertaken. Main outcome measures were incidence of TIA and stroke, rates of referral for specialist opinion, prescription of antiplatelet agents and rates of CEA.

Results

There were twofold differences (P &lt; 0·00005, χ2 test) in the incidence of cerebrovascular disease between Regional Health Authorities (RHAs) between the years 1992 and 1996 and also for each year. Mean stroke incidence per annum was 143 per 100 000 and TIA incidence 183 per 100 000. Yorkshire had the highest incidence at 170 (stroke) and 206 (TIA) per 100 000 of the population compared with 95 and 98 per 100 000 for Oxford. Some 37 per cent of new patients with stroke and 19 per cent of patients with TIA were referred for specialist opinion following initial diagnosis. These rates did not change over time. There was no positive correlation between disease incidence and referral rate; Yorkshire referred the least (14 per cent) and Oxford the most (26 per cent). The majority of referrals for TIA were made to general medicine (39 per cent); 6 per cent of patients were referred directly for surgical opinion. Mean prescription rate of antiplatelet medication over the time period was 17 per cent for patients with stroke and 35 per cent for those with TIA. Mean CEA rate for English RHAs for the time interval was 15·5 per 100 000. There was a positive correlation between the incidence of disease and rate of CEA, with the regions with the highest incidence of disease tending to perform the most CEAs.

Conclusion

The incidence of cerebrovascular disease varies significantly across health regions in the UK. There was no correlation between the regional incidence of disease and the number of patients referred for specialist opinion, but CEA rates were generally correlated with the regional difference in incidence of disease. The low referral rate may be a factor in the perceived underperformance of CEA in the UK and the low usage of antiplatelet medication is surprising.

Avoiding artificiality in teleconsultations

The ideal videoconferencing environment would produce the minimum feeling of artificiality for its users. We assessed nurse and patient perceptions of artificiality by varying the technical and operational procedures for telemedicine in a minor injuries unit. Twenty-five patients and eight emergency nurse practitioners (ENPs) participated in simulated teleconsultations under a variety of different conditions and completed a Likert-scale survey. There was a close correlation between the ENPs' ratings and the patients' ratings for the various factors (r > 0.99). In relation to technical factors, a flicker-free television screen and the user being seated close to the screen were preferred. Similarly, in relation to operational procedures, an initial explanation of telemedicine, introductions and adequate preparation were also preferred. The study suggests that careful attention to technical specifications and operational procedures can reduce the perceived artificiality of teleconsultations.

Effect of octreotide on small intestinal motility in HIV-infected patients with chronic refractory diarrhea

Octreotide has been used to treat HIV-associated diarrhea. We aimed to assess the effect of octreotide on small intestinal motility in a group of HIV infected individuals with chronic diarrhea. Small intestinal motility was measured continuously for 48 hr by ambulatory strain gauge manometry in 12 HIV seropositive subjects with chronic diarrhea. During the second 24-hr period, intravenous octreotide was administered (100 microg every 8 hr). Postprandial and nocturnal fasting motility data were compared before and during administration of octreotide. Octreotide was associated with increased numbers of migrating motor complexes (MMCs) (7.25 vs 4.92, P = 0.03), and a relative decrease in the duration of phase II (22% vs 49.8, P = 0.03) during nocturnal fasting activity. Postprandial activity was absent in half of the subjects and the duration significantly reduced in the remainder. In conclusion, octreotide has a significant effect on small intestinal motility in HIV-infected individuals with diarrhea, which may influence intestinal transit.

Increased chromosome translocations and aneuploidy in peripheral blood lymphocytes of patients having revision arthroplasty of the hip

The long-term biological effects of wear debris are unknown. We have investigated whether there is any evidence of cumulative mutagenic damage in peripheral blood lymphocytes of patients undergoing revision arthroplasty of predominantly metal-on-plastic total hip replacements compared with those at primary arthroplasty. There was a threefold increase in aneuploidy and a twofold increase in chromosomal translocations which could not be explained by the confounding variables of smoking, gender, age and diagnostic radiographs. In the patients with TiVaAl prostheses there was a fivefold increase in aneuploidy but no increase in chromosomal translocations. By contrast, in patients with cobalt-chrome prostheses there was a 2.5-fold increase in aneuploidy and a 3.5-fold increase in chromosomal translocations. In six patients with stainless-steel prostheses there was no increase in either aneuploidy or chromosomal translocations. Our results suggest that future epidemiological studies of the putative long-term risks of joint replacement should take into account the type of alloy used in the prosthesis.

Increased chromosome translocations and aneuploidy in peripheral blood lymphocytes of patients having revision arthroplasty of the hip

The long-term biological effects of wear debris are unknown. We have investigated whether there is any evidence of cumulative mutagenic damage in peripheral blood lymphocytes of patients undergoing revision arthroplasty of predominantly metal-on-plastic total hip replacements compared with those at primary arthroplasty.

There was a threefold increase in aneuploidy and a twofold increase in chromosomal translocations which could not be explained by the confounding variables of smoking, gender, age and diagnostic radiographs. In the patients with TiVaAl prostheses there was a fivefold increase in aneuploidy but no increase in chromosomal translocations. By contrast, in patients with cobalt-chrome prostheses there was a 2.5-fold increase in aneuploidy and a 3.5-fold increase in chromosomal translocations. In six patients with stainless-steel prostheses there was no increase in either aneuploidy or chromosomal translocations.

Our results suggest that future epidemiological studies of the putative long-term risks of joint replacement should take into account the type of alloy used in the prosthesis.

Comparison of virologic, immunologic, and clinical response to five different initial protease inhibitor-containing and nevirapine-containing regimens

CONTEXT

The effectiveness of different protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors outside the setting of clinical trials has not been well described.

OBJECTIVES

To compare five different PI-and nevirapine (NVP)-containing regimens on virologic, immunologic, and clinical outcomes and treatment discontinuation.

DESIGN AND SETTING

Observational cohort study based on an HIV clinic in London.

PATIENTS

A total of 690 patients who received either saquinavir hard gel (SQV HG) (n = 183), indinavir (IDV) (n = 189), nelfinavir (NFV) (n = 109), ritonavir (RTV) (n = 42), ritonavir with saquinavir hard gel (RTV/SQV HG) (n = 45), or NVP (n = 122) as part of an initial PI-or NVP-containing treatment regimen between November 1994 and December 1998. A total of 351 (51%) patients had prior exposure to nucleoside reverse transcriptase inhibitors (NRTIs).

MAIN OUTCOME MEASURES

The main outcome measures were virologic undetectability, subsequent virologic rebound, CD4 cell count rise, development of AIDS, and treatment discontinuation. All analyses were stratified for year of initiation of the PI-or NVP-containing regimen.

RESULTS

Overall, 63% of patients attained an undetectable viral load (VL) within 6 months of starting their PI or NVP regimen. The adjusted relative hazard (95% confidence interval [CI]) for an undetectable VL relative to SQV HG was (in rank order): 2.77 (CI: 1.84-4.17) for NFV, 2.54 (CI: 1.81-3.57) for IDV, 2.43 (CI: 1.52-3.87) for RTV, 2.08 (CI: 1.28-3.37) for RTV/SQV HG, and 1.96 (CI: 1.35-2.85) for NVP. Forty-nine percent of patients experienced VL rebound within 12 months of initial attainment of undetectability, but relative to SQV HG, this did not differ significantly across the different PI and NVP regimens. The CD4 cell count response and rate of AIDS events were also similar across the different regimens. No independent predictors of VL undetectability were identified, but prior NRTI exposure was associated with VL rebound, and a lower baseline VL and CD4 cell count were associated with a reduced CD4 count response. The frequency (95% CI) of treatment discontinuation differed across the regimens; at 6 months, it was lowest for NFV (18% [CI: 13%-24%]), IDV (25% [CI: 22%-29%]), and NVP (28% [CI: 22%-34%]) and highest for RTV (41% [CI: 31%-52%]) and SQV HG (52% [CI: 48%-57%]).

CONCLUSIONS

Although PI- and NVP-containing regimens were similar in their CD4 cell count response and rates of subsequent VL rebound, differences were observed in time to VL undetectability and discontinuation rates relative to SQV HG. SQV HG was consistently inferior to the other PIs and NVP. The use of NFV and IDV was associated with the highest rates of undetectability, and together with NVP, the lowest rates of discontinuation.

Diagnosis and initial management of stroke and transient ischemic attack across UK health regions from 1992 to 1996: experience of a national primary care database

BACKGROUND AND PURPOSE

The aim of this study was to establish the difference in burden of cerebrovascular disease across the different health regions of the United Kingdom and to determine whether the initial management of new cases of stroke and transient ischemic attack (TIA) was uniform across the United Kingdom:

METHODS

The General Practice Research Database (GPRD) is a national database used for epidemiological studies. This was a cohort study identifying incident cases of stroke and TIA over a 5-year study period between 1992 and 1996. The population studied was patients registered with general practitioners contributing to the GPRD across the different health regions of the United Kingdom: Outcome measures were new diagnoses of stroke and TIA, new prescriptions for antiplatelet and anticoagulant agents, and referrals made for specialist opinion.

RESULTS

The age-adjusted annual incidence rate across all regions was 151 per 100 000 for stroke and 190 per 100 000 for TIA. There was almost a 2-fold difference in the incidence of cerebrovascular disease between the regions. The management of stroke and TIA in terms of antiplatelet prescription and of referral onward for further opinion to hospital specialists varied significantly between regions.

CONCLUSIONS

Reported stroke and TIA incidence on the GPRD was comparable to that of other European studies. There were striking regional differences in the incidence of disease. The primary care management, both in prescription and referral rates, varied significantly between the different regions. There was a marked underuse of antiplatelet and anticoagulant agents, and referral rates for specialists' opinions were low.

HLA-C and guttate psoriasis

BACKGROUND

Psoriasis is a heterogeneous disease in its clinical expression. Both genetic and environmental factors are thought to contribute to the pathogenesis of the inflammatory and hyperproliferative components of the typical skin lesions. Predisposing genetic influences include associations with human leucocyte antigens (HLA) of which that with HLA-Cw6 is the strongest. Guttate psoriasis is a specific clinical manifestation of psoriasis frequently associated with group A beta-haemolytic streptococcal throat infection.

OBJECTIVES

We set out to determine whether further clinical subdivision of psoriasis is associated with tighter correlation with HLA-C alleles.

PATIENTS/METHODS

We determined the HLA-C locus genotype of 29 caucasian patients with guttate psoriasis presenting consecutively with guttate psoriasis associated with a history of a sore throat and/or an antistreptolysin O titre > 200 IU mL-1. Polymerase chain reaction typing using sequence-specific primers was used to detect all known HLA-C alleles. These data were compared with a control population of 604 random caucasian cadaver donors.

RESULTS

All patients (100%) with guttate psoriasis carried the Cw*0602 allele compared with 20% of the control population (odds ratio = infinity; 95% confidence limits 25.00-infinity; Pcorrected < 0.0000002).

CONCLUSIONS

This result is consistent with HLA-Cw*0602 playing a part directly in the pathogenesis of guttate psoriasis.

Fungal and other spore counts as predictors of admissions for asthma in the Trent region

OBJECTIVES

The importance of airborne fungal and other spores in provoking asthma attacks is uncertain. Panel studies have generated evidence that suggests a link between outdoor spore counts and severity of asthma. There have been no population based time series studies relating outdoor exposure to spores with incidence of attacks of asthma.

METHODS

Outcomes were hospital admissions for asthma on 2002 days during 1987-94, for children and adults in the Trent region of England. Predictors were daily counts of 25 spore taxa from volumetric traps in Derby on the same and previous day. Admissions for asthma were adjusted for weekly, seasonal, and longer term trends by log linear autoregressive models. Spore counts on 6 days of asthma epidemics were also examined.

RESULTS

When spore counts for individual taxa were analysed as quantitative variables, two positive and two negative correlations (out of a possible 100) were significant at the 5% level. When spore counts were dichotomised at the 90th percentile, one negative and eight positive correlations (out of 100) were significant at the 5% level. All significantly positive associations related to admissions among children, but none involved the total spore count. However, total spores were above the 90th percentile on four of the six epidemic days (odds ratio (OR) 9.92, 95% confidence interval (95% CI) 1.41 to 109.84), but epidemics occurred on only four of 343 days with high total moulds.

CONCLUSIONS

There was some evidence that exceptional rates of admission for asthma tend to occur on days with high total mould spore counts, but no specific taxon was consistently implicated. The predictive power was insufficient to support a public warning system.

A comparison of telemedicine with face-to-face consultations for trauma management

We compared the accuracy of teleconsultations for minor injuries with face-to-face consultations. Two hundred patients were studied. Colour change, swelling, decreased movement, tenderness, instability, radiological examination, severity of illness, treatment and diagnosis were recorded for both telemedicine and face-to-face consultations. Colour change showed an accuracy of 97%, presence of swelling or deformity of 98%, diminution of joint movement of 95%, presence of tenderness of 97%, weight bearing and gait of 99%, and radiological diagnosis of 98%. The severity of illness or injury was overestimated in one case and underestimated in five cases. Treatment was over-prescribed in one case and under-prescribed in three cases. The final diagnosis was correct in all but the two cases in which mistakes were made in the teleradiology. Overall, there was good accuracy using teleconsultations.

How do teleconsultations for remote trauma management change over a period of time?

We obtained follow-up information about the new patients seen at a minor accident and treatment service (MATS) staffed by emergency nurse practitioners (ENPs). A previous study, of 150 teleconsultations in a six-month period starting in April 1996, was used for comparison. In the present series, 150 teleconsultations occurring in a four-month period starting in April 1999 were studied; the patients constituted 5.6% of the 2658 new attenders or 3.8% of the 3936 total attenders. In comparison with the study three years before, falling teleconsultation rates were partly offset by increasing numbers of attenders and an extension of the ENPs' roles and skills. Teleconsultation rates rose when the number of consultant-run clinics was curtailed and ENP-run clinics replaced some of them. Eligibility to request and report more radiographs reduced the need for teleconsultations, and subsequently teleconsultations for help with interpretation of radiographs fell as the ENPs became more experienced. Specialty residents trusted ENP judgement and accepted telephoned direct admission of cases to their wards. Fewer teleconsultations were required for soft-tissue injuries. Telemedicine is an excellent educational tool.

Circumcision and genital dermatoses

CONTEXT

It is well recognized that the presence of a foreskin predisposes to penile carcinoma and sexually transmitted infections. We have investigated the relationship between the presence or absence of the foreskin and penile dermatoses.

OBJECTIVE

To determine whether there is an association between circumcision and penile dermatoses.

DESIGN

A retrospective case control study of patients attending the department of dermatology with genital skin conditions.

SUBJECTS

The study population consisted of 357 male patients referred for diagnosis and management of genital skin disease. The control population consisted of 305 male patients without genital skin disease attending the general dermatology clinics over a 4-month period.

MAIN OUTCOME MEASURES

The relationship between circumcision and the presence or absence of skin disease involving the penis was investigated. The rate of circumcision in the general male dermatology population was determined.

RESULTS

The most common diagnoses were psoriasis (n = 94), penile infections (n = 58), lichen sclerosus (n = 52), lichen planus (n = 39), seborrheic dermatitis (n = 29), and Zoon balanitis (n = 27). Less common diagnoses included squamous cell carcinoma (n = 4), bowenoid papulosis (n = 3), and Bowen disease (n = 3). The age-adjusted odds ratio for all penile skin diseases associated with presence of the foreskin was 3.24 (95% confidence interval, 2.26-4.64). All patients with Zoon balanitis, bowenoid papulosis, and nonspecific balanoposthitis were uncircumcised. Lichen sclerosus was diagnosed in only 1 circumcised patient. Most patients with psoriasis, lichen planus, and seborrheic eczema (72%, 69%, and 72%, respectively) were uncircumcised at presentation. The majority of men with penile infections (84%) were uncircumcised.

CONCLUSIONS

Most cases of inflammatory dermatoses were diagnosed in uncircumcised men, suggesting that circumcision protects against inflammatory dermatoses. The presence of the foreskin may promote inflammation by a köebnerization phenomenon, or the presence of infectious agents, as yet unidentified, may induce inflammation. The data suggest that circumcision prevents or protects against common infective penile dermatoses.

Decreased morbidity and use of hospital services in English HIV-infected individuals with increased uptake of anti-retroviral therapy 1996-1997. National Prospective Monitoring System Steering Group

OBJECTIVE

To investigate the relationship between changing morbidity patterns, the use of hospital services by HIV-infected patients and the uptake of antiretroviral therapy (ART) in England.

DESIGN

Prospective serial cross-sectional analyses based on data collected through the National Prospective Monitoring System (NPMS), a multi-centre prospective monitoring system.

SETTING

HIV-infected patients seen in 10 clinics, five London and five non-London, during the three semesters, 1 January 1996 to 30 June 1997.

MAIN OUTCOME MEASURES

The mean use of hospital services per patient-year, mean new HIV-related opportunistic illnesses per 1000 patient-years and percentage uptake of ART.

RESULTS

The use of inpatient services changed particularly among AIDS patients. The mean number of inpatient days for AIDS patients decreased from 19.7 [95% confidence interval (CI) 13.7-25.7] in 1996 to 11.2 (95% CI 6.1-15.6) per patient-year in 1997. Concurrently the number of new AIDS-defining events decreased significantly from 567 (95% CI 529-607) to 203 (95% CI 183-225) per 1000 patient-years. The overall uptake of ART increased significantly from 33% (95% CI 31-35%) to 50% (95% CI 48-52%), and a switch from mono or dual to triple therapy or quadruple or more therapy was observed. However, by mid-1997 only 29% (95% CI 26-32%) of asymptomatic patients and 51% (95% CI 49-54%) of patients with symptomatic non-AIDS were on ART, compared with 69% (95% CI 66-71%) of AIDS patients.

CONCLUSION

The observed reduction in new AIDS-defining events has led to a reduction in the need for inpatient hospital care and has been associated with an increased uptake of ART, including a switch to triple therapy. All of these factors are likely to have contributed to the observed reduction in mortality among English AIDS patients. As the overall uptake of ART remained relatively low in English centres further improvements can be anticipated. However, the medium to long-term effects of these treatment regimens will need to be closely monitored.

Better by half: hypertension in the elderly and the 'rule of halves': a primary care audit of the clinical computer record as a springboard to improving care

BACKGROUND

Despite recent studies highlighting the benefits of treating elderly hypertensives, researchers have shown that the taking on board of these findings has been disappointing in primary care, where the 'rule of halves' still applies. Clinical computers could help performance in this area, yet national and local research suggests that they are under-used.

OBJECTIVE

Our aim is to develop a pragmatic intervention which aims to: improve patient care by translating research findings into practice, increase meaningful computer use, establish 'paperless' annual audits and improve 'networking' between practices.

METHOD

Following a baseline audit to ascertain accuracy, the computer records of participating practices were tested against the 'rule of halves' for hypertension. Results were presented to each practice (individual practice and aggregate data for all practices). Management guidelines, standardization of computer recording, achievable targets and review dates were agreed. The study was conducted in West London practices using the EMIS computer system in 1996/1997.

RESULTS

An 81% (22/27) practice response rate was achieved. Baseline audit was completed for 22 practices. Fifteen practices appear to be using their computer regularly (two-thirds). Using strict definitions, 'the rule of halves' still applies. Using looser definitions, three-quarters of hypertensives are known, two-thirds are treated and just under two-thirds are controlled. This project identified wide inter- and intra-practice variation in: use of the computer, patient follow-up, attainment of target BP, rounding BP readings to target levels and prescribing patterns.

CONCLUSION

This focused training intervention has introduced practices to evidence-based proactive care and highlighted an important application for clinical computers. A local network of practices has been established for future projects. For elderly patients registered with a GP, the rule of halves has been improved upon, provided that a figure of 160/90 is taken as an adequate control. Attainment of target BP in treated hypertensives was similar to that reported from large trials. There is enormous scope for improving identification and follow-up of hypertensives using clinical computers and systematic models of care. The wide inter-practice variation in hypertension management requires further study.

Should doctors practise resuscitation skills on newly deceased patients? A survey of public opinion

Trainee doctors must acquire skills in resuscitation, but opportunities for learning on real patients are limited. One option is to practise these skills in newly deceased patients. We sought opinions from 400 multiethnic guests at an open-access dinner dance for members of a local community. The questionnaire could elicit the responses strongly agree, agree, unsure, disagree or strongly disagree. 332 (83%) guests responded. For non-invasive techniques, 32% of responders supported practice without consent, 74% with consent. Support diminished with increasing invasiveness of procedure. 91% of the sample were uncomfortable about the procedures, the commonest reason being 'respect for the body' (264/302). 86% of responders felt that practice should last for no more than 5 minutes. The most popular solutions were for people to carry a personal card giving consent (89%) and establishment of a central register of individuals consenting to be practised upon after death (79%).

HLA-Cw*0602 and HIV-associated psoriasis

The aetiopathogenesis of psoriasis is unknown, but genetic and environmental factors may be involved. Psoriasis may not be one disease but a cutaneous inflammatory reaction pattern consequent upon several different independent or related stimuli in susceptible individuals. There are controversial issues regarding the immunological basis of psoriasis and the role of CD4 vs. CD8 T lymphocytes. Psoriasis has been associated with HLA-Cw6 and Cw7 by serology and specifically with HLA-Cw*0602 by polymerase chain reaction (PCR) typing. Psoriasis is probably no more common in HIV infection than in the general population; however, it may appear for the first time or pre-existing psoriasis may worsen and be difficult to treat in HIV disease. We have investigated the prevalence of HLA-C alleles, in the specific clinical context of HIV infection complicated by type 1 psoriasis, in a case control study of 14 men with HIV disease and type 1 psoriasis and 147 HIV-infected patients without psoriasis. Typing was performed using PCR with sequence-specific amplification primers. Eleven of 14 patients (79%) with psoriasis carried the HLA-Cw*0602 allele compared with 24.5% of those without psoriasis (odds ratio = 11.31; 95% confidence limits 2. 73 to 65.36; P = 0.0001). Two patients without the HLA-Cw*0602 allele carried instead the closely related Cw*0401/3 allele. The results confirm the previously reported association between the HLA-Cw*0602 allele and type 1 psoriasis, and suggest that the association with HLA-Cw*0602 is stronger in HIV-associated psoriasis although this trend needs to be supported by a larger sample. The immunodysregulation resulting from HIV infection may trigger psoriasis in those genetically predisposed by the Cw*0602 allele. As CD8 T cells recognize antigens in the context of class I major histocompatibility complex, the identification of an HLA class I association in HIV-associated psoriasis strengthens the argument for an important role for CD8 + T lymphocytes in the immunopathogenesis of psoriasis. Investigations of the pathogenesis of psoriasis should take account of clinical and other subtypes already identified.

Relationship between the regional and national incidence of transient ischaemic attack and stroke and performance of carotid endarterectomy

OBJECTIVES

To examine the relationship between the incidence of transient ischaemic attack (TIA) and stroke on a national and regional level and the rate of carotid endarterectomy (CEA).

SUBJECTS

Patients entered onto a national primary care computerised database with a new diagnostic code of stroke or TIA between 1992 and 1995.

METHODS

Analysis of data from the primary care database and routine data sources. Main outcome measures were incidence of TIA and stroke and rates of CEA.

RESULTS

The mean incidence per 100,000 of the population was 292 (TIA) and 356 (stroke) in England, 391 and 497 in Scotland and 349 and 448 in Northern Ireland. There was a variation in the incidence of TIA and stroke between both the regions and the regions and countries which was significant. There was a national increase in the rate of CEA between 1990 and 1995 which showed a marked variation across the regions. The inter-regional variation in rate of CEA correlated with the inter-regional difference in incidence of disease.

CONCLUSIONS

The incidence of TIA and stroke may be higher than previously recognised, and varies significantly between the regions. This is generally associated with the variation in performance of CEA.

Acute asthma epidemics, weather and pollen in England, 1987-1994

Recent epidemics of acute asthma have caused speculation that, if their causes were known, early warnings might be feasible. In particular, some epidemics seemed to be associated with thunderstorms. We wondered what risk factors predicting epidemics could be identified. Daily asthma admissions counts during 1987-1994, for two age groups (0-14 yrs and > or = 15 yrs), were measured using the Hospital Episodes System (HES). Epidemics were defined as combinations of date, age group and English Regional Health Authority (RHA) with exceptionally high asthma admission counts compared to the predictions of a log-linear autoregression model. They were compared with control days 1 week before and afterwards, regarding seven meteorological variables and 5 day average pollen counts for four species. Fifty six asthma epidemics were identified. The mean density of sferics (lightning flashes), temperature and rainfall on epidemic days were greater than those on control days. High sferics densities were overrepresented in epidemics. Simultaneously high sferics and grass pollen further increased the probability of an epidemic, but only to 15% (95% confidence interval 2-45%). Two thirds of epidemics were not preceded by thunderstorms. Thunderstorms and high grass pollen levels precede asthma epidemics more often than expected by chance. However, most epidemics are not associated with thunderstorms or unusual weather conditions, and most thunderstorms, even following high grass pollen levels, do not precede epidemics. An early warning system based on the indicators examined here would, therefore, detect few epidemics and generate an unacceptably high rate of false alarms.

Acute asthma epidemics, weather and pollen in England, 1987-1994

Recent epidemics of acute asthma have caused speculation that, if their causes were known, early warnings might be feasible. In particular, some epidemics seemed to be associated with thunderstorms. We wondered what risk factors predicting epidemics could be identified. Daily asthma admissions counts during 1987-1994, for two age groups (0-14 yrs and > or = 15 yrs), were measured using the Hospital Episodes System (HES). Epidemics were defined as combinations of date, age group and English Regional Health Authority (RHA) with exceptionally high asthma admission counts compared to the predictions of a log-linear autoregression model. They were compared with control days 1 week before and afterwards, regarding seven meteorological variables and 5 day average pollen counts for four species. Fifty six asthma epidemics were identified. The mean density of sferics (lightning flashes), temperature and rainfall on epidemic days were greater than those on control days. High sferics densities were overrepresented in epidemics. Simultaneously high sferics and grass pollen further increased the probability of an epidemic, but only to 15% (95% confidence interval 2-45%). Two thirds of epidemics were not preceded by thunderstorms. Thunderstorms and high grass pollen levels precede asthma epidemics more often than expected by chance. However, most epidemics are not associated with thunderstorms or unusual weather conditions, and most thunderstorms, even following high grass pollen levels, do not precede epidemics. An early warning system based on the indicators examined here would, therefore, detect few epidemics and generate an unacceptably high rate of false alarms.

Effect of thunderstorms and airborne grass pollen on the incidence of acute asthma in England, 1990-94

BACKGROUND

Thunderstorms and prior grass pollen counts were investigated as predictors of daily hospital admissions for asthma in England. This study was motivated by reports in the literature of spectacular asthma epidemics associated with thunderstorms, particularly in the grass pollen season.

METHODS

Asthma admissions for two age groups (0-14 years and 15 and over) were measured using the Hospital Episodes System (HES) in the 14 regional health authorities (RHAs) in England. Thunderstorms were measured daily in each RHA using densities of sferics (lightning flashes). Relative asthma excesses for moderate positive and exceptionally high sferic densities, with or without previous high grass pollen counts, were measured using log linear autoregression--allowing for weekly, seasonal, and longer term background variation--and pooled over RHAs by calculating geometric means.

RESULTS

Relative risks from all RHAs were pooled to form geometric means. Exceptional sferic densities were associated with a relative excess risk of around 25% in both age groups. Moderate sferic densities were associated with a smaller excess, statistically significant in the two age groups taken together. In five RHAs in which grass pollen counts were available, high pollen counts for the previous five days were associated with an amplification of the excess associated with thunderstorms.

CONCLUSION

Very large sferic densities are associated with moderate rises in hospital admissions for acute asthma. However, typical thunderstorm days are not associated with spectacular asthma epidemics of the scale previously reported in the literature. Thunderstorm-associated excesses are amplified after a run of high pollen counts.

Treated blood pressure, rather than pretreatment, predicts survival in hypertensive patients. A report from the DHSS Hypertension Care Computing Project (DHCCP)

A group of hypertensive patients (n = 2855) with an untreated diastolic blood pressure greater than or equal to 90 mmHg were followed in the Department of Health and Social Security (DHSS) Hypertension Care Computing Project (DHCCP) for periods of up to 10 years. During this period 191 of these patients died. Survival was assessed in relation to pretreatment blood pressure levels and blood pressure achieved during treatment. The blood pressure during treatment was a useful predictor of mortality, but the pretreatment pressure was not. After adjusting for age, mortality was particularly related to the height of the systolic and diastolic blood pressure during the second and third years of treatment. In men, age-standardized 5-year mortality was greater than 10% in those with a first year treated systolic pressure greater than 150 mmHg or a diastolic pressure greater than 95 mmHg. In women, age standardized 5-year mortality was greater than 5% with the same levels of treated blood pressure. The longest survival occurred with the lowest bands of treated pressure, i.e. systolic pressure less than 140 and diastolic pressure less than 90 mmHg; the 5-year mortality being less than 7% in men and less than 3% in women. Treated systolic and diastolic pressures were useful in predicting death from ischaemic heart disease (IHD).

The relationship between a low treated blood pressure and IHD mortality: a report from the DHSS Hypertension Care Computing Project (DHCCP)

The suggestion that treating blood pressure to below a certain level may increase IHD mortality is controversial. We investigated the influence of treated blood pressure on mortality in the DHSS Hypertension Care Computer Project. Mortality was examined by quintiles of treated diastolic blood pressure (DBP) in 2,145 patients treated for a minimum period of one year and subsequently followed for an average of four years. One hundred and seventy five patients died; 71 from IHD. In men and women all cause mortality increased with level of treated DBP. In men IHD mortality showed a U-shaped distribution with an age-adjusted rate of 15.2 per 1,000 person years in the lowest fifth (DBP less than 86 mmHg) comparable to that of 15.6 per 1,000 in the upper (DBP greater than or equal to 103 mmHg). A similar pattern could not be established in women due to very few IHD deaths. IHD mortality was further examined separately for men by prior history of IHD. An increase in IHD deaths in the lowest fifth of treated blood pressure was found for men both with and without a history of IHD. No similar pattern of IHD mortality was obtained for untreated DBP or treated systolic pressure. However, we cannot exclude the possibility that the risk of low treated DBP is secondary to ischaemic heart disease.