Is it beneficial to increase the provision of thrombolysis?-- a discrete-event simulation model

BACKGROUND

Although Thrombolysis has been licensed in the UK since 2003, it is still administered only to a small percentage of eligible patients.

AIM

We consider the impact of investing the impact of thrombolysis on important acute stroke services, and the effect on quality of life. The concept is illustrated using data from the Northern Ireland Stroke Service.

DESIGN

Retrospective study.

METHODS

We first present results of survival analysis utilizing length of stay (LOS) for discharge destinations, based on data from the Belfast City Hospital (BCH). None of these patients actually received thrombolysis but from those who would have been eligible, we created two initial groups, the first representing a scenario where they received thrombolysis and the second comprising those who do not receive thrombolysis. On the basis of the survival analysis, we created several subgroups based on discharge destination. We then developed a discrete event simulation (DES) model, where each group is a patient pathway within the simulation. Coxian phase type distributions were used to model the group LOS. Various scenarios were explored focusing on cost-effectiveness across hospital, community and social services had thrombolysis been administered to these patients, and the possible improvement in quality of life, should the proportion of patients who are administered thrombolysis be increased. Our aim in simulating various scenarios for this historical group of patients is to assess what the cost-effectiveness of thrombolysis would have been under different scenarios; from this we can infer the likely cost-effectiveness of future policies.

RESULTS

The cost of thrombolysis is offset by reduction in hospital, community rehabilitation and institutional care costs, with a corresponding improvement in quality of life.

CONCLUSION

Our model suggests that provision of thrombolysis would produce moderate overall improvement to the service assuming current levels of funding.

Antimicrobial susceptibilities and resistance genes in Campylobacter strains isolated from poultry and pigs in Australia

AIMS

To evaluate the phenotypic and genotypic profiles of Campylobacter spp. from poultry faecal samples from free range or intensively raised meat chickens and free range egg layers. In addition, a case-comparison study of antibiotic resistance genes from different groups of poultry and some pig strains previously collected was carried out.

METHODS

Resistance to different antibiotics was assessed using the agar dilution method. In addition, all the strains were tested for ampicillin (bla(OXA-61) ), erythromycin (aph-3-1), tetracycline tet(O), streptomycin (aadE), and the energy-dependent multi-drug efflux pump (cmeB) resistance genes using multiplex polymerase chain reaction.

RESULTS

The evaluation of phenotypic resistance revealed all of the strains from poultry were sensitive to ciprofloxacin, gentamicin, erythromycin or tylosin. But, widespread resistance to lincomycin (51-100%), extensive resistance to ampicillin (33·3-60·2%) and less resistance to tetracycline (5·6-40·7%) were observed in the different groups of chickens. Antibiotic resistance genes bla(OXA-61,) cmeB and tet(O) were found in 82·6-92·7%, 80·3-89% and 22·3-30·9% Camp. coli isolates from pigs, whilst 59-65·4% and 19·2-40·7% Camp. jejuni from chickens were found to encode bla(OXA-61) and tet(O), respectively.

CONCLUSION

No significant difference between isolates from free range egg layers and meat chickens (P < 0·05) was found. However, there were significant differences between the pig strains and all the groups of poultry strains (P < 0·05) with regard to carriage of resistance genes. In addition, pulsed field gel electrophoresis of selected resistant isolates from the poultry and pig revealed closely related clonal groups.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results suggest the resistant strains are persisting environmental isolates that have been acquired by the different livestock species. Furthermore, the different treatment practices in poultry and pigs have resulted in differences in resistance profiles in Campylobacter isolates.

Socio-demographic and other patient characteristics associated with time between colonoscopy and surgery, and choice of treatment centre for colorectal cancer: a retrospective cohort study

OBJECTIVES

To investigate key patient clinical and demographic characteristics associated with time between colonoscopy and surgery, and choice of treatment centre for colorectal cancer (CRC) patients. This will add to the little published research examining the pathway following CRC diagnosis and prior to surgery.

DESIGN

Retrospective cohort analysis of linked data.

SETTING

A population-based sample of people diagnosed August 2004 to December 2007 in New South Wales, Australia.

PARTICIPANTS

569 CRC patients, of whom 407 (72%, 95% CI 68% to 75%) had colonoscopy followed by surgery.

PRIMARY OUTCOME MEASURES

Time between colonoscopy and surgery, and whether the surgery took place in a specialist cancer centre.

RESULTS

Among the 407 eligible patients analysed, the median time from colonoscopy to surgery was 19 days (IQR 12-29 days). After adjusting for key demographic and clinical characteristics such as age and disease stage, the time was longer for rectal cancer patients and those reporting fair/poor health, although differences in medians were <5 days. 24% (95% CI 20% to 28%) had surgery in a specialist cancer centre, which was more common among people resident in metropolitan areas (37% vs 14% for others, adjusted p=0.001) and those without private health insurance (30% vs 21% for others, adjusted p=0.03).

CONCLUSIONS

There do not appear to be systemic issues affecting time from colonoscopy to surgery related to patients' socio-demographic characteristics. However, patients with private insurance and those living in rural areas may be less likely to receive optimal specialist treatment. A more systematic approach might be needed to ensure cancer patients are treated in specialist cancer centres, particularly patients requiring more specialised treatment.

Obesity, insulin resistance and diabetes: sex differences and role of oestrogen receptors

Obesity increases the risk of coronary artery disease through insulin resistance, diabetes, arterial hypertension and dyslipidemia. The prevalence of obesity has increased worldwide and is particularly high among middle-aged women and men. After menopause, women are at an increased risk to develop visceral obesity due to the loss of endogenous ovarian hormone production. Effects of oestrogens are classically mediated by the two nuclear oestrogen receptors (ERs) α and β. In addition, more recent research has shown that the intracellular transmembrane G-protein-coupled oestrogen receptor (GPER) originally designated as GPR30 also mediates some of the actions attributed to oestrogens. Oestrogen and its receptors are important regulators of body weight and insulin sensitivity not only in women but also in men as demonstrated by ER mutations in rodents and humans. This article reviews the role of sex hormones and ERs in the context of obesity, insulin sensitivity and diabetes as well as the related clinical issues in women and men.

Apparatus for dimensional characterization of fused silica fibers for the suspensions of advanced gravitational wave detectors

Detection of gravitational waves from astrophysical sources remains one of the most challenging problems faced by experimental physicists. A significant limit to the sensitivity of future long-baseline interferometric gravitational wave detectors is thermal displacement noise of the test mass mirrors and their suspensions. Suspension thermal noise results from mechanical dissipation in the fused silica suspension fibers suspending the test mass mirrors and is therefore an important noise source at operating frequencies between ∼10 and 30 Hz. This dissipation occurs due to a combination of thermoelastic damping, surface and bulk losses. Its effects can be reduced by optimizing the thermoelastic and surface loss, and these parameters are a function of the cross sectional dimensions of the fiber along its length. This paper presents a new apparatus capable of high resolution measurements of the cross sectional dimensions of suspension fibers of both rectangular and circular cross section, suitable for use in advanced detector mirror suspensions.

'GAP' in radiotherapy services in Australia and New Zealand in 2009

AIM

In this study we estimated (a) the number of linear accelerators required in Australia and New Zealand to achieve a 52.3% treatment rate; (b) the 'GAP' between the actual and required number of linear accelerators; c) the number of persons not treated (PNT), premature deaths (PD) and years of life lost (YLL) as a result of the 'GAP'; and (d) to review the actions being taken by health jurisdictions in Australia and in New Zealand to address the 'GAP' and reach the 52.3% treatment rate.

MATERIAL AND METHODS

The actual number of fully staffed and operating linear accelerators (A) in Australian and New Zealand was obtained from a survey of radiotherapy facilities in December 2009. The required number of linear accelerators (R) was calculated from the projected cancer incidence figures for 2009 and was based on 1.6 linear accelerators being required per 1000 new cancer patients. The 'GAP' in Radiotherapy services (G) was R minus A. The maximum treatment capacity (MTC) was the ratio of A over R multiplied by 52.3%, assuming that all linear accelerators were operating at 100% capacity. As each linear accelerator can treat 331 new patients each year, the number of new cancer PNT is G x 331. The estimated 5-year survival benefit from radiotherapy is 16%, and the average survival for all patients receiving radiotherapy (radical and palliative) is 0.76 year. Hence, the number of PD attributed to the 'GAP' is PNT x 16%, and the YLL to cancer is PNT x 0.76. A literature search and local knowledge of health department Radiotherapy Plans in all jurisdictions were used to determine the action being taken to achieve a 52.3% treatment rate.

RESULTS

In 2009, the 'GAP' was 50 linear accelerators in Australia and the MTC was 38%, the same as it was in 1999, but there has been an increase in PNT each year from 7419 in 1999 to 16,550 in 2009, and PD each year increased from 1187 in 1999 to 2649 in 2009, and YLL each year increased from 5638 in 1999 to 12,585 in 2009. In New Zealand in 2009, the 'GAP' was nine linear accelerators and the MTC was 38%. An estimated 3310 persons did not receive radiotherapy in 2009 in New Zealand, and as a result, there were 523 PD and 2266 YLL. The review showed that new and replacement machines were being installed in all jurisdictions in Australia and in New Zealand. Only Victoria and Queensland have a Radiotherapy Plan beyond 2010, but both have underestimated the projected cancer incidence.

CONCLUSION

Urgent action is needed by health departments and governments on both sides of the Tasman to improve access and equity to this essential cancer treatment. There is merit in the Baume Report recommendation of establishing a national body to oversee radiotherapy services in all jurisdictions in Australia. A similar central body should also be considered for New Zealand.

Management of skin toxicity during radiation therapy: a review of the evidence

Acute skin toxicity occurs in the majority of the patients undergoing radical radiotherapy. While a variety of topical agents and dressing are used to ameliorate side effects, there is minimal evidence to support their use. The aims of this study were to systematically review evidence on acute skin toxicity management and to assess the current practices in ANZ. A systematic review of the literature was conducted on studies published between 1980 and 2008. A meta-analysis was performed on articles on clinical trials reporting grade II or greater toxicity. Analyses were divided into breast (the most common site) and other sites. A survey of Radiation Oncology departments across ANZ was conducted to identify patterns of practices and compare these with the published evidence. Twenty-nine articles were reviewed. Only seven articles demonstrated statistically significant results for management of side-effects. These were for topical corticosteroids, hyaluronic acid, sucralfate, calendula, Cavilon cream (3M, St Paul, Minnesota, USA) and silver leaf dressing. Meta-analysis demonstrated statistical significance for the prophylactic use of topical agents in the management acute toxicity. The survey of departments had a low response rate but demonstrated variation in skin care practices across ANZ. A considerable number of these practices were based only on anecdotal evidence. Lack of evidence in the literature for the care of radiation skin reactions was associated with variation in practice. Only a limited number of studies have demonstrated a significant benefit of specific topical agents. There is a need for objective and prospective recording of skin toxicity to collect meaningful comparative data on which to base recommendations for practice.

Exploring beyond viral load testing for EBV lymphoproliferation: role of serum IL-6 and IgE assays as adjunctive tests

We examined serum IL-6 and IgE assays as adjuncts to VL monitoring for PTLD. Paediatric solid organ transplant recipients were followed with VL monitoring. VL, IL-6, and IgE assays were compared between PTLD cases and non-cases at <3, 3-6 and >6 months after transplantation. Median IL-6 levels in PTLD cases were 15.5 (2.0-87.1) and 23.3 (2.1-276) pg/mL compared with 3.25 (0.92-114) and 3.5 (0.75-199.25) pg/mL in non-cases at 3-6 and >6 months, respectively (p = 0.006 and p = 0.005). At >6 months, IL-6 levels correlated with VL and PTLD occurrence (Spearman's coefficients = 0.40; p = 0.001 and 0.32; p = 0.003) in univariate analyses. No benefit was derived from performance of IgE levels. The sensitivity and specificity of high VL as a test of PTLD were 76.3% and 92.5%, while the negative predictive value and PPV of VL were 94.9% and 68.4%, respectively. Combining elevated IL-6 with high VL increased the PPV and specificity to 80% and 96.2%, respectively, and improved the receiver operating characteristic curve. Serum IL-6 levels can improve the clinician's ability to identify PTLD, among patients with elevated EBV viral loads.

The phylogeny of the red panda (Ailurus fulgens): evidence from the forelimb

Within the order Carnivora, the phylogeny of the red panda (Ailurus fulgens) is contentious, with morphological and molecular studies supporting a wide range of possible relationships, including close ties to procyonids, ursids, mustelids and mephitids. This study provides additional morphological data, including muscle maps, for the forelimb of Ailurus, based on the dissection of four cadavers from the National Zoological Park, Washington, DC, USA. The red panda forelimb is characterized by a number of primitive features, including the lack of m. rhomboideus profundus, a humeral insertion for m. cleidobrachialis, the presence of mm. brachioradialis, articularis humeri and coracobrachialis, a single muscle belly for m. extensor digitorum lateralis with tendons to digits III-V, four mm. lumbricales, and the presence of mm. flexor digitorum brevis manus, adductores digiti I, II and V, and abductor digiti I and V. Red pandas resemble Ailuropoda, mustelids and some procyonids in possessing a soft tissue origin of m. flexor digitorum superficialis. In addition, red pandas are similar to ursids and procyonids in having a variable presence of m. biceps brachii caput breve. Furthermore, Ailurus and some ursids lack m. rhomboideus capitis. The forelimb muscle maps from this study represent a valuable resource for analyzing the functional anatomy of fossil ailurids and some notes on the Miocene ailurid, Simocyon batalleri, are presented.

Pneumococcal meningitis in Jamaican children

OBJECTIVE

To describe the clinical features and outcome of pneumococcal meningitis in Jamaican children.

METHODS

All patients admitted to the Bustamante Hospital for Children, during the period 1995-1999, who had pneumococcus isolated from cerebrospinal fluid (CSF) or pleocytosis in association with a blood culture isolate of pneumococcus were selected. Demographic, clinical and laboratory data were collected.

RESULTS

Twenty-five (23%) of 111 patients with pneumococcal infections satisfied criteria for meningitis. The median age was 8 months (range 0.5-60 months). There were 4 (16%) cases of sickle cell disease, 2 (50%) of whom were first diagnosed during the current illness. This represents a 53-fold increased risk of pneumoccocal meningitis in patients with Sickle-cell disease based on population prevalence rates. Oxacillin resistance occurred in 3 (12%) patients, one of whom died. Mortality rate was 12% (3) with all deaths occurring in infants < 1 year. Poor outcome occurred in 36% (9) of the patients. Of the (35%) 8 survivors who had follow-up evaluation, (38%) 3 had documented hearing loss.

CONCLUSIONS

Meningitis is a common clinical syndrome of invasive pneumococcal disease, occurring in 23% of cases resulting in mortality and high morbidity among Jamaican children. Local seroepidemiological studies are urgently needed to inform national vaccine decisions. As an interim plan, policymakers should consider a risk-based strategy to vaccine prophylaxis that will ensure that high risk groups such as children with sickle cell disease are offered currently available conjugate pneumococcal vaccines.

Patients' and health care professionals' evaluation of health-related quality of life issues in bone metastases

The objective of this study was to examine the agreement between health care professionals' (HCPs) and patients' evaluation of health-related quality of life (HRQOL) issues for cancer patients with bone metastases. A total of 413 patients and 152 HCPs were interviewed across five centres worldwide. Mean scores were almost always higher for HCPs than for patients. Patients and HCPs agreed that four issues affect HRQOL of bone metastases patients profoundly: 'long-term (chronic) pain', 'difficulty in carrying out usual daily tasks', 'able to perform self-care' and 'able to perform role functioning'. A substantial difference was found with respect to the perceived importance of psychosocial and somatic issues. Patients emphasised psychosocial issues with a particular focus on 'worry' about loss of mobility, dependence on others and disease progression, HCPs however rated 'symptom' issues as more important, specifically those related to 'pain'. In conclusion, patients and HCPs agreed that pain and physical/role functioning are important to the HRQOL of cancer patients with bone metastases, but patients also emphasized the importance of psychosocial issues to HRQOL. This information has been an important component in the development of a health-related quality of life questionnaire for patients with bone metastases (EORTC QLQ-BM 22).