Endotoxin Removal from Albumin and Saline Solutions

Microporous membranes have been developed which can remove endotoxins selectively from electrolyte and albumin solutions by regioselective adsorption in the membrane matrix and outside surface of the membrane. The membranes were prepared in the form of hollow fibre membranes in a continuous process. By varying the membrane preparation parameters, different pore sizes and adsorption capacities could be realized, thus broadening applications for biological purification. Dynamic adsorption capacities for endotoxin from albumin and saline solution were determined and were found to be in the range of 0.2 and 0.1 μg endotoxin/g membrane, respectively, suggesting different adsorption mechanisms. (Int J Artif Organs 2007; 30: 589–93)

Effect of an antimicrobial stewardship programme on antimicrobial utilisation and costs in patients with leukaemia: a retrospective controlled study

OBJECTIVES

To examine the effectiveness of an antimicrobial stewardship programme on utilization and cost of antimicrobials in leukaemia patients in Canada.

METHODS

We conducted a multisite retrospective observational time series study from 2005 to 2013. We implemented academic detailing as the intervention of an antimicrobial stewardship programme in leukaemia units at a hospital, piloted February-July 2010, then fully implemented December 2010-March 2013, with no intervention in August-November 2010. Internal control was the same hospital's allogeneic haematopoietic stem-cell transplantation unit. External control was the combined leukaemia-haematopoietic stem-cell transplantation unit at another hospital. Primary outcome was antimicrobial utilization (antibiotics and antifungals) in defined daily dose per 100 patient-days (PD). Secondary outcomes were antimicrobial cost (Canadian dollars per PD); cost and utilization by drug class; length of stay; 30-day inpatient mortality; and nosocomial Clostridium difficile infection. We used autoregressive integrated moving average models to evaluate the impact of the intervention on outcomes.

RESULTS

The intervention group included 1006 patients before implementation and 335 during full implementation. Correspondingly, internal control had 723 and 264 patients, external control 1395 and 864 patients. Antimicrobial utilization decreased significantly in the intervention group (p <0.01, 278 vs. 247 defined daily dose per 100 PD), increased in external control (p = 0.02, 237.4 vs. 268.9 defined daily dose per 100 PD) and remained stable in internal control (p = 0.66). Antimicrobial cost decreased in the intervention group (p = 0.03; $154.59 per PD vs. $128.93 per PD), increased in external control (p = 0.01; $109.4 per PD vs. $135.97 per PD) but was stable in internal control (p = 0.27). Mortality, length of stay and nosocomial C. difficile rate in intervention group remained stable.

CONCLUSIONS

The antimicrobial stewardship programme reduced antimicrobial use in leukaemia patients without affecting inpatient mortality and length of stay.

Clinical predictors and clinical prediction rules to estimate initial patient risk for infective endocarditis in Staphylococcus aureus bacteraemia: a systematic review and meta-analysis

OBJECTIVES

We conducted a meta-analysis to summarize diagnostic properties of risk factors and clinical prediction rules for diagnosing infective endocarditis (IE) in Staphylococcus aureus bacteraemia (SAB).

METHODS

We searched MEDLINE, Embase, and the Cochrane Database from inception to 6 January 2016 to identify studies evaluating risk factors and clinical prediction rules for IE in SAB patients. Pooled estimates of diagnostic properties for main risk factors were calculated using a bivariate random effects model.

RESULTS

Of 962 articles identified, 30 studies were included. These involved 16 538 SAB patients including 1572 IE cases. Risk factors with positive likelihood ratio (PLR) greater than 5 included embolic events (PLR 12.7, 95% CI 9.2-17.7), pacemakers (PLR 9.7, 95% CI 3.7-21.2), history of previous IE (PLR 8.2, 95% CI 3.1-22.0), prosthetic valves (PLR 5.7, 95% CI 3.2-9.5), and intravenous drug use (PLR 5.2, 95% CI 3.8-6.9). The only clinical factor with negative likelihood ratio (NLR) less than 0.5 was documented clearance of bacteraemia within 72 hours (NLR range 0.32-0.35). Of the nine published clinical prediction rules for ruling out IE, five had an NLR below 0.1.

CONCLUSIONS

SAB patients with high-risk features (embolic events, pacemakers, prosthetic valves, previous IE, or intravenous drug use) should undergo a trans-esophageal echocardiography (TEE) for IE. Clinical prediction rules show promise in safely ruling out endocarditis, but require validation in future studies.

Linking live animals and products: traceability

It is rarely possible to successfully contain an outbreak of an infectious animal disease, or to respond effectively to a chemical residue incident, without the use of a system for identifying and tracking animals. The linking of animals at the time they are slaughtered--through the use of identification devices or marks and accompanying movement documentation--with the meat produced from their carcasses, adds further value from the perspective of consumer safety. Over the past decade, animal identification technology has become more sophisticated and affordable. The development of the Internet and mobile communication tools, complemented bythe expanded capacity of computers and associated data management applications, has added a new dimension to the ability of Competent Authorities and industry to track animals and the food they produce for disease control, food safety and commercial purposes.

Efficacy of pine oil as repellent to wildlife

Pine oil, a by-product of the pulp industry, is a feeding repellent to snowshoe hares and voles. In pen trials with snowshoe hares and field trials with voles, when given a choice between food in a pine oil-treated bowl and a control bowl, the animals fed preferentially from the control bowl. When the hares were presented with food only in a pine oil-treated bowl, two hares showed a reduced rate of food consumption and one hare did not feed at all. Pine oil contains monoterpenes which may inhibit microbial symbionts in the digestive tracts of hares and voles. The repellent action of pine oil is likely based on this interference of digestive processes, and it is of adaptive advantage for cecal digestors to avoid it. Pine oil has potential as a commercial repellent for snowshoe hares and voles.

Screening for hepatitis B surface antigen before chemotherapy: current practice and opportunities for improvement

INTRODUCTION

Hepatitis B virus (hbv) reactivation is a recognized complication of chemotherapy. The U.S. Centers for Disease Control and Prevention recommend that all patients be screened for the hbv surface antigen (hbsag) before chemotherapy. We sought to determine the frequency of hbsag testing before chemotherapy at our hospital and to increase the frequency of testing to more than 90% of patients starting chemotherapy.

METHODS

Using a retrospective electronic chart review, we identified the frequency of hbsag testing for patients initiated on intravenous chemotherapy at out institution between March 2006 and March 2007. The frequency of left ventricular function testing in the subgroup of patients receiving potentially cardiotoxic chemotherapy was identified as a comparator. An educational intervention was developed and delivered to the multidisciplinary oncology team. The frequency of hbsag testing was determined post intervention. Qualitative interviews were conducted with the members of the oncology team to identify risk perception and barriers to testing.

RESULTS

Of 208 patients started on intravenous chemotherapy between March 2006 and March 2007, only 28 (14%) were tested for hbsag. All 138 patients scheduled for cardiotoxic chemotherapy (100%) underwent left ventricular function testing. In the post-intervention phase, of 74 patients started on intravenous chemotherapy, 24 (31%) underwent hbsag testing, with 1 patient testing positive.

CONCLUSIONS

The frequency of testing for hbsag before chemotherapy was very low at our institution. An educational intervention resulted in only a modest improvement. Potential barriers to routine screening include lack of awareness about existing guidelines, controversy about the evidence that supports hbsag testing guidelines, and a perception by physicians that hbv reactivation does not occur with solid tumours.

Diagnostic features of feline restrictive orbital myofibroblastic sarcoma

A progressive debilitating disease of the orbit and adjacent connective tissues of cats has historically been called feline orbital pseudotumor. The authors reviewed clinical, histopathologic, and diagnostic imaging features of this disease in 12 cases from the Comparative Ocular Pathology Laboratory of Wisconsin. The cats' ages ranged from 7 to 16 years (mean, 10.8 years). All cats had a history of severely restricted mobility of the globe and eyelids with secondary corneal disease. Eleven cats (92%) had concurrent involvement of the contralateral eye and/or the oral cavity. Diffuse scleral or episcleral thickening was seen with computed tomography in all clinically affected eyes. Histologically, an insidious infiltration of neoplastic spindle cells in the orbit, eyelids, and periorbital skin and soft tissues, with collagen deposition and a few perivascular lymphocytes, led to entrapment and restricted mobility of the eyelids and orbital tissues. The tumor failed to form a discrete mass, and it spread along fascial planes to the contralateral orbit and eyelids and/or the lips and oral cavity. In all tested cases (n = 10), neoplastic cells were immunohistochemically positive for vimentin, S100 protein, and smooth muscle actin. The authors adopted the term feline restrictive orbital myofibroblastic sarcoma to reflect the restricted mobility of the eyelids and globe and the imaging and histologic features of an invasive yet low-grade myofibroblastic sarcoma.

Published randomized controlled trials of drug therapy for dementia often lack complete data on harm

OBJECTIVE

The objective of the study was to determine the extent to which published randomized controlled trials (RCTs) report data on harm.

STUDY DESIGN AND SETTING

A systematic search strategy was used to identify RCTs published between 1996 and 2005 on the use of cholinesterase inhibitors or atypical antipsychotics in patients with dementia. A structured abstraction form was used to determine if data on mortality or serious adverse events were reported and if the articles followed Consolidated Standards of Reporting Trials format for reporting harm.

RESULTS

Thirty-three RCTs were identified (27 on cholinesterase inhibitors and 6 on atypical antipsychotics). Nineteen trials (58%) had explicit data on mortality and only four (12%) reported regulatory-agency-defined serious adverse events. Most abstracts (31, 94%) stated that harm was studied but few studies (9, 27%) provided a clear definition of the measures of harm.

CONCLUSIONS

Although most published RCTs state that they examine harm, many failed to provide data on mortality and most lacked clear definitions or detailed analyses of harm. Better reporting of harm would provide timely and important information that could help physicians and the public to make more informed decisions.

Brief overview of maternal triglycerides as a risk factor for pre-eclampsia

BACKGROUND

Features of the metabolic syndrome-maternal obesity, diabetes mellitus and chronic hypertension-are risk factors for pre-eclampsia.

OBJECTIVES

To determine the risk of pre-eclampsia in the presence of maternal hypertriglyceridemia, another major element of the metabolic syndrome.

SEARCH STRATEGY

Two investigators independently searched PubMed and Embase databases from 1980 to December 2004 for relevant studies. The terms preeclampsia, eclampsia, pregnancy-induced hypertension or toxemia were combined with dyslipidemia, hyperlipidemia, hypertriglyceridemia, lipids, cholesterol, triglycerides (TG) or lipoprotein.

SELECTION CRITERIA

We included case-control and cohort studies published in English that included at least 20 women with pre-eclampsia and that sampled serum or plasma TG at any time before, during or after pregnancy.

DATA COLLECTION AND ANALYSIS

Mean maternal TG concentrations were compared between cases and controls within each study. The odds ratio of pre-eclampsia was calculated by comparing the risk of pre-eclampsia among women in each higher TG concentration category with that in the lowest reference category.

MAIN RESULTS

A total of 19 case-control and 3 prospective cohort studies were included. In 14 studies, the mean TG concentration was significantly higher among pre-eclamptic cases than among unaffected controls; in seven other studies, there was a nonsignificant trend in the same direction. The risk of pre-eclampsia typically doubled with each increasing TG category. In the four studies that adjusted for potential confounders, such as maternal age, parity and body mass index, there was about a four-fold higher risk of pre-eclampsia in the highest relative to the lowest TG category.

AUTHOR'S CONCLUSIONS

There exists a consistent positive association between elevated maternal TG and the risk of pre-eclampsia. Given that maternal hypertriglyceridemia is a common feature of the metabolic syndrome, interventional studies are needed to determine whether pre-pregnancy weight reduction and dietary modification can lower the risk of pre-eclampsia.

Beta-blocker therapy failures in symptomatic probands with genotyped long-QT syndrome

Beta-blocker therapy is one of the principal therapies for congenital long-QT syndrome (LQTS). However, breakthrough cardiac events occur while being treated with beta-blockers. We sought to determine the frequency of and clinical correlates underlying beta-blocker therapy failures in genotyped, symptomatic LQTS probands. The medical records were analyzed only for genotyped LQTS probands who presented with a LQTS-attributable clinical event and were receiving beta-blocker therapy. The study cohort comprised 28 such patients: 18 KCNQ1/KVLQT1(LQT1), 7 KCNH2/HERG (LQT2), and 3 SCN5A (LQT3). The prescribed beta-blocker was atenolol (12), propranolol (10), metoprolol (4), and nadolol (2). Beta-blocker therapy failure was defined as breakthrough cardiac events including syncope, aborted cardiac arrest (ACA), appropriate implantable cardioverter-defibrillator (ICD) therapy, or sudden death occurring while on beta-blocker therapy. During a median follow-up of 46 months, 7/28 (25%) LQTS probands experienced a total of 15 breakthrough cardiac events. Their initial presentation was ACA (3), bradycardia during infancy (2), and syncope (2). The underlying genotype was KVLQT1 (6) and HERG (1). Two breakthroughs were attributed to noncompliance. Of the 13 breakthroughs occurring while compliant, 10 occurred with atenolol and 3 with propranolol (p = 0.03). In this study cohort, one-fourth of genotyped LQTS probands failed beta-blocker therapy. Treatment with atenolol, young age at diagnosis, initial presentation with ACA, KVLQT1 genotype, and noncompliance may be important factors underlying beta-blocker therapy failures.

Cancer risks in women with 2 breast or ovarian cancers: clues to genetic cancer susceptibility

Women diagnosed with 2 cancers of the breast and/or ovary are at higher risk of developing subsequent cancers. Using registrations from the Thames Cancer Registry, we quantified the risks at different cancer sites. Increased risks were found for cancers that are part of the BRCA1 and BRCA2 tumour spectrum: oropharyngeal cancer, malignant melanoma of the skin (BRCA2) and colon cancer (BRCA1). We also found significantly increased risks of myeloid leukaemia (probably due to radiotherapy) and of cancer of the corpus uteri (which may be due to hormonal factors).

Mortality among patients admitted to hospitals on weekends as compared with weekdays

BACKGROUND

The level of staffing in hospitals is often lower on weekends than on weekdays, despite a presumably consistent day-to-day burden of disease. It is uncertain whether in-hospital mortality rates among patients with serious conditions differ according to whether they are admitted on a weekend or on a weekday.

METHODS

We analyzed all acute care admissions from emergency departments in Ontario, Canada, between 1988 and 1997 (a total of 3,789,917 admissions). We compared in-hospital mortality among patients admitted on a weekend with that among patients admitted on a weekday for three prespecified diseases: ruptured abdominal aortic aneurysm (5454 admissions), acute epiglottitis (1139), and pulmonary embolism (11,686) and for three control diseases: myocardial infarction (160,220), intracerebral hemorrhage (10,987), and acute hip fracture (59,670), as well as for the 100 conditions that were the most common causes of death (accounting for 1,820,885 admissions).

RESULTS

Weekend admissions were associated with significantly higher in-hospital mortality rates than were weekday admissions among patients with ruptured abdominal aortic aneurysms (42 percent vs. 36 percent, P<0.001), acute epiglottitis (1.7 percent vs. 0.3 percent, P=0.04), and pulmonary embolism (13 percent vs. 11 percent, P=0.009). The differences in mortality persisted for all three diagnoses after adjustment for age, sex, and coexisting disorders. There were no significant differences in mortality between weekday and weekend admissions for the three control diagnoses. Weekend admissions were also associated with significantly higher mortality rates for 23 of the 100 leading causes of death and were not associated with significantly lower mortality rates for any of these conditions.

CONCLUSIONS

Patients with some serious medical conditions are more likely to die in the hospital if they are admitted on a weekend than if they are admitted on a weekday.

The association between caregiver burden and caregiver health-related quality of life in Alzheimer disease

The burden experienced by family caregivers of individuals with Alzheimer disease (AD) affects the caregivers' overall health-related quality of life (HRQOL). Assessing the influence on HRQOL is an integral part of determining the efficacy and economic attractiveness of interventions for AD. Generic preference-weighted instruments such as the Health Utilities Index Mark 2 (HUI2) are recommended for measuring HRQOL for cost-effectiveness studies. However, these instruments focus on physical attributes and have not been tested in an AD caregiver population. We administered the HUI2 to a population of 679 caregivers to people with AD at 13 community and institutional sites in the United States. We also administered the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), a caregiver time questionnaire, and a caregiver burden instrument. The mean global HUI2 utility score for caregivers was 0.87 and varied little by the affected person's setting of care and AD stage (range, 0.86-0.89; p > 0.2). The caregiver burden scales all varied by the affected person's setting of care, and some also varied by disease severity. The mental health component summary score of the SF-36 for caregivers varied across both disease stage and setting. Caregiver time increased for caregivers of AD-affected persons with more severe cognitive impairment. Generic preference-weighted instruments may not adequately capture differences in the burden of caregivers of those with AD. The development of condition-specific preference-weighted instruments may provide the means to better estimate HRQOL in AD caregivers.

An off-the-shelf help list: a comprehensive catalog of preference scores from published cost-utility analyses

PURPOSE

The Panel on Cost-Effectiveness in Health and Medicine recommends an organized collection of preference measure values for health states that can be used in costutility analyses (CUAs). The authors sought to construct a catalog of preference scores from published CUAs, organize the catalog by clinical categories, and identify methods of preference score assessment.

METHOD

The authors systematically searched Medline and other databases to identify original CUAs published through 1997. Information was abstracted on the health state descriptions, corresponding preference scores, method of preference score elicitation, and the source of the estimate.

RESULTS

Two hundred twenty-eight CUAs were appraised. The authors found 949 health states and corresponding preference scores. Most frequently, health states pertained to the circulatory system (21.7%), health states were valued by experts (35.8%), and values were derived through community-based preference scores (23.5%).

CONCLUSION

A catalog of preference scores for health states can be constructed. The catalog (http://www.hsph.harvard.edu/organizations/hcra/cuadatabase/ intro.html) may provide a useful reference tool for producers and consumers of CUAs but also underscores the methodologic variation and inconsistencies present in the field.

Incidence of multiple primary cancers in a cohort of women diagnosed with breast cancer in southeast England

Among women in the Thames Cancer Registry database with a first breast cancer diagnosed between 1961-1995 observed numbers of subsequent cancers were compared with expected numbers and standardized incidence ratios were calculated. The occurrence of breast cancers subsequent to cancers at other sites was also examined. Women diagnosed with breast cancer before age 50 had significantly elevated risks for 9 cancer sites namely, oesophagus, stomach, lung, bone, connective tissue, breast, corpus uteri, ovary and myeloid leukaemia compared with 2 sites (corpus uteri and myeloid leukaemia) in women diagnosed at age 50 and above. Some of these associations are consistent with the effects of known inherited cancer susceptibility genes, shared environmental factors, or therapy.

Understanding variations in survival for colorectal cancer in Europe: a EUROCARE high resolution study

BACKGROUND

Marked differences in population based survival across Europe were found for colorectal cancers diagnosed in 1985-1989.

AIMS

To understand the reasons for these differences in survival in a new analysis of colorectal cancers diagnosed between 1988 and 1991.

SUBJECTS

A total of 2720 patients with adenocarcinoma of the large bowel from 11 European cancer registries (CRs).

METHODS

We obtained information on stage at diagnosis, diagnostic determinants, and surgical treatment (not routinely collected by CRs) and analysed the data in relation to three year observed survival, calculating relative risks (RRs) of death and adjusting for age, sex, site, stage, and determinants of stage.

RESULTS

Three year observed survival rates ranged from 25% (Cracow) to 59% (Modena), and were low in the Thames area (UK) (38%). Survival rates between registries for "resected" patients varied less than those for all patients. When age, sex, and site were considered, RRs ranged from 0.7 (95% confidence intervals (CI) 0.6-0.9) (Modena) to 2.3 (95% CI 1.9-2.9) (Cracow). After further adjustment by stage, between registry RR variation was between 0.8 (95% CI 0.6-0.9) and 1.8 (95% CI 1.5-2.2). Inter-registry RR differences were slightly reduced when the determinants of stage (number of nodes examined and liver imaging) were included in the model. The reduction was marked for the UK registries.

CONCLUSIONS

The wide differences across Europe in colorectal cancer survival depend to a large extent on differences in stage at diagnosis. There are wide variations in diagnostic and surgical practices. There was a twofold range in the risk of death from colorectal cancer even after adjustment for surgery and disease stage.

Systematic overview of cost-utility assessments in oncology

PURPOSE

Cost-utility analyses (CUAs) present the value of an intervention as the ratio of its incremental cost divided by its incremental survival benefit, with survival weighted by utilities to produce quality-adjusted life years (QALYs). We critically reviewed the CUA literature and its role in informing clinical oncology practice, research priorities, and policy.

METHODS

The English-language literature was searched between 1975 and1997 for CUAs. Two readers abstracted from each article descriptions of the clinical situation and patients, the methods used, study perspective, the measures of effectiveness, costs included, discounting, and whether sensitivity analyses were performed. The readers then made subjective quality assessments. We also extracted utility values from the reviewed papers, along with information on how and from whom utilities were measured.

RESULTS

Our search yielded 40 studies, which described 263 health states and presented 89 cost-utility ratios. Both the number and quality of studies increased over time. However, many studies are at variance with current standards. Only 20% of studies took a societal perspective, more than a third failed to discount both the costs and QALYs, and utilities were often simply estimates from the investigators or other physicians.

CONCLUSION

The cost-utility literature in oncology is not large but is rapidly expanding. There remains much room for improvement in the methodological rigor with which utilities are measured. Considering quality-of-life effects by incorporating utilities into economic studies is particularly important in oncology, where many therapies obtain modest improvements in response or survival at the expense of nontrivial toxicity.

The quality of reporting in published cost-utility analyses, 1976-1997

PURPOSE

Cost-utility analysis is a type of cost-effectiveness analysis in which health effects are measured in terms of quality-adjusted life-years (QALYs) gained. Such analyses have become popular for examining the health and economic consequences of health and medical interventions, and they have been recommended by leaders in the field. These recommendations emphasize the importance of good reporting practices. This study determined 1) the quality of reporting in published cost-utility analyses through 1997 and 2) whether reporting practices have improved over time. We examined quality of reporting by journal type and number of cost-utility analyses a journal has published.

DATA SOURCES

Computerized databases were searched through 1997 for the Medical Subject Headings or text keywords quality-adjusted, QALY, and cost-utility analysis. Published bibliographies of the field were also searched.

STUDY SELECTION

Original cost-utility analyses written in English were included. Cost-effectiveness analyses that measured health effects in units other than QALYs and review, editorial, or methodologic articles were excluded.

DATA EXTRACTION

Each of the 228 articles found was audited independently by two trained readers who used a standard data collection form to determine the quality of reporting in several categories: disclosure of funding, framing, reporting of costs, reporting of preference weights, reporting of results, and discussion.

RESULTS

The number of cost-utility analyses in the medical literature increased greatly between 1976 and 1997. Analyses covered a wide range of diseases and interventions. Most studies listed modeling assumptions (82%), described the comparator intervention (83%), reported sensitivity analysis (89%), and noted study limitations (84%). Only 52% clearly stated the study perspective; 34% did not disclose the funding source. Methods of reporting costs and preference weights varied widely. The quality of published analyses improved slightly over time and was higher in general clinical journals and in journals that published more of these analyses.

CONCLUSIONS

The study results reveal an active and evolving field but also underscore the need for more consistency and clarity in reporting. Better peer review and independent, third-party audits may help in this regard. Future investigations should examine the quality of clinical and economic assumptions used in cost-utility analyses, in addition to whether analysts followed recommended protocols for performance and reporting.

Charges for medical care at different hospitals

BACKGROUND

The United States has a high proportion of people without health insurance (15%) and a low proportion of people without employment (5%), resulting in millions who lack insurance but have some ability to pay. We tested whether hospitals charge similar prices for well-specified elective services to individuals paying out-of-pocket for medical care.

METHODS

We surveyed the 2 largest general hospitals from every large city (population >500 000) in the United States and Canada. At each hospital we evaluated 5 diagnostic, 7 therapeutic, and 3 nonclinical services to determine the total charge to patients who pay directly.

RESULTS

Overall, 66 hospitals were included (average, 758 beds; not-for-profit, 97% [n = 64]; teaching, 80% [n = 53]). The range in charges was substantial; for example, a screening mammogram was $40 at one hospital in Los Angeles, Calif, and $346 at one hospital in Quebec City. Charges for a screening mammogram were relatively stable between 1996 and 1997 (r=0.79; 95% confidence interval, 0.68-0.87) and unrelated to the hospital's location or charges for other services. The relative amount of variation in charges was similar for high-priced and low-priced services, similar for diagnostic and therapeutic services, and similar for the United States and Canada.

CONCLUSIONS

Charges for the same hospital service vary substantially. Greater visibility might reduce some variation by bringing outliers into closer scrutiny. Patients seeking care and paying out-of-pocket could save financially by comparison shopping.

Methodological issues in the use of guidelines and audit to improve clinical effectiveness in breast cancer in one United Kingdom health region

AIMS

To develop a system to improve and monitor clinical performance in the management of breast cancer patients in one United Kingdom health region.

DESIGN

An observational study of the changes brought about by the introduction of new structures to influence clinical practice and monitor change.

SETTING

North Thames (East) Health region, comprising seven purchasing health authorities and 21 acute hospitals treating breast cancer.

SUBJECTS

The multi-disciplinary breast teams in 21 hospitals and an audit sample of 419 (28%) of the breast cancer patients diagnosed in 1992 in the region.

INTERVENTIONS

Evidence-based interventions for changing clinical practice: regional guidelines, senior clinicians acting as <<opinion leaders>>, audit of quality rather than cost of services, ownership of data by clinicians, confidential feed-back to participants and education.

OUTCOME MEASURES

Qualitative measures of organizational and behavioural change. Quantitative measures of clinical outcomes compared to guideline targets and to results from previous studies within this population.

RESULTS

Organizational changes included the involvement, participation of and feedback to 16 specialist surgeons and their multidisciplinary teams in 21 hospitals. Regional clinical guidelines were developed in 6 months and the dataset piloted within 9 months. The audit cycle was completed within 2 years. The pilot study led to prospective audit at the end of 2 years for all breast cancers in the region and a 15-fold increase in high quality clinical information for these patients. Changes in clinical practice between 1990 and 1992 were observed in the use of chemotherapy (up from 17-23%) and axillary surgery (up from 46-76%).

CONCLUSIONS

The approach used facilitated rapid change and found a balance between local involvement (essential for sustainability within a hospital setting) and regional standardization (essential for comparability across hospitals). The principles of the approach are generalized to other cancers and to other parts of the UK and abroad.

Are pharmaceuticals cost-effective? A review of the evidence

The argument that prescription drugs are cost-effective has been made both by the pharmaceutical industry to support rising drug prices and expenditures, and by advocates of expanded drug coverage for elderly and low-income persons. A new database of 228 published cost-utility analyses sheds light on the issue. According to published data, some drugs do save money or are cost-effective, but the issue depends critically on the context in which the drug is used and the intervention with which it is compared. Cost-utility analyses funded by the drug industry tend to report more favorable results than do those funded by nonindustry sources. Cost-effectiveness analysis can help policymakers to determine whether drugs and other interventions offer value for money.

Shopping around for hospital services: a comparison of the United States and Canada

CONTEXT

Historical comparisons indicate that US hospitals are more expensive than Canadian hospitals, but health care system reform might have changed the relative costs and timeliness of health care in the 2 countries.

OBJECTIVE

To estimate the price and convenience of selected hospital services in the United States and Canada for patients in 1997 had they paid out-of-pocket.

DESIGN

Cross-sectional telephone survey conducted May 1996 to April 1997.

PARTICIPANTS

The 2 largest acute care general hospitals from every city in the United States and Canada with a population greater than 500000.

MEASURES

Each hospital was telephoned and asked their price and waiting time for 7 services: magnetic resonance imaging of the head without gadolinium; a screening mammogram; a 12-lead electrocardiogram; a prothrombin time measurement; a session of hemodialysis; a screening colonoscopy; and a total knee replacement. Waiting times were measured in days until earliest appointment and charges were converted to American currency.

RESULTS

Overall, 48 US and 18 Canadian hospitals were surveyed. Median waiting times were significantly shorter in American hospitals for 4 services, particularly a magnetic resonance imaging of the head (3 days vs 150 days; P<.001). Median charges were significantly higher in American hospitals for 6 services, particularly for a total knee replacement ($26805 vs $10651; P<.001). Individual services showed no association between shorter waiting times and higher prices within each country, with the exception of a total knee replacement in the United States.

CONCLUSION

US hospitals still provide higher prices and faster care than Canadian hospitals for patients who pay out-of-pocket.

Safety of topical 5-aminosalicylic acid in pregnancy

OBJECTIVE

To assess the safety and efficacy of topical 5-aminosalicylic acid preparations for therapy of distal colitis during pregnancy.

METHODS

Nineteen pregnancies in sixteen consecutive patients with proven distal colitis were identified prospectively at a tertiary care center. All patients were given trials of weaning off medication and all failed. All subjects were on maintenance topical 5-aminosalicylic acid therapy at the time of conception. They were followed throughout their pregnancy and thereafter. Their children were also closely examined and followed by a pediatrician.

RESULTS

The mean age at delivery was 25.8 yr, and the mean duration of illness was 4.6 yr. After taking topical therapy, there were no relapses during the pregnancy. There were 19 successful full-term pregnancies with no fetal abnormalities. The mothers and children were followed for more than 6 months.

CONCLUSION

In this series, topical 5-aminosalicylic acid appears safe, effective, and well tolerated in the management of pregnant patients with distal colitis.

Stationary interphases with extended alkyl chains: a comparative study on chain order by solid-state NMR spectroscopy

Stationary interphases with long n-alkyl chains (n = 18, 22, 30, 34) have been examined by solid-state NMR spectroscopy. The determination of the silane functionality and the degree of cross-linking of silane ligands on the silica surface was performed by 29Si CP/MAS NMR spectroscopy. High-speed 1H MAS and 13C CP/MAS NMR spectroscopy were utilized to assess alkyl chain order and mobility of the different bonded phases. For this purpose, 1H NMR line widths and 13C chemical shifts have been evaluated. It is shown that stationary phase order and rigidity increase with alkyl chain length. In addition, the temperature-dependent trans/gauche conformational change occurs at higher temperatures for a polymeric C34 phase compared with a C30 sorbent. This behaviour is discussed in the context of previously reported chromatographic (HPLC) shape selectivity differences.

Management of breast cancer in southeast England

OBJECTIVE

To examine the extent to which management of invasive breast cancer reflected consensus guidelines in the Thames regions in 1990.

DESIGN

Population based study of case notes.

SETTING

Thames Cancer Registry.

SUBJECTS

All women with breast cancer diagnosed in early 1990 (417 cases) resident in the four Thames regions. Hospital records were traced for 346 cases, of which 12 were ineligible because of misclassification in initial registration and were excluded from the analysis. 334 cases were analysed.

MAIN OUTCOME MEASURES

Investigations and treatment in the six months after diagnosis, stage of disease.

RESULTS

Of the 334 women identified, 86 were aged under 50. Three years after diagnosis, 74 were dead, seven (8%) aged under 50 and 67 (27%) aged 50 or over. Axillary surgery was used to stage cancer in only 155 cases (46%), although this is recommended in the guidelines. Only 79 (24%) case notes had any information recorded on stage. Stage could be determined reliably for only half of the sample. Treatment varied widely within the same age group and stage of disease. In particular, chemotherapy was not routinely given to patients under 50 with stage II disease. Only 17 records showed evidence that the patient was participating in a clinical trial.

CONCLUSIONS

There was a lack of consensus on the management of breast cancer among clinicians in 1990. More patients should be included in clinical trials.

Diethyl ether interference with infrared breath analysis

Diethyl ether vapor may substantially interfere with breath alcohol analysis by instruments based on infrared absorption at 9.5 microns. Exposure of two volunteers simultaneously to diethyl ether vapor for one hour followed immediately by breath tests on the Draeger Alcotest 7110, Siemens Alcomat V5.2F, and Seres Ethylometre 679T produced apparent alcohol readings in one subject of 0.4, 0.1, and 0.1 g/100 mL of blood respectively. Positive readings persisted in this subject for more than 3 hours. The second subject produced much lower readings of 0.03, 0.01, and 0.00, respectively. Readings persisted with the Alcotest 7110 for one hour. Gas chromatographic analyses of blood and breath samples confirmed that these readings were caused by diethyl ether and not ethanol. The blood concentration of diethyl ether in Subject A immediately after exposure was 25 mg/L. This level produced no clinically detectable neurological changes in the subject.

An open controlled assessment of osteopathic manipulation in nonspecific low-back pain

An open controlled pilot trial on nonspecific low-back pain sufferers demonstrated responsiveness to osteopathic manipulation of some patients presenting with pain durations of 14 to 28 days. No response was demonstrated in those with shorter episodes at presentation. The advantage to manipulated patients was maximal between 1 and 2 weeks after commencing treatment, but was not discernable after 4 weeks. The demonstration of a similar responsive stratum by other investigators, with both teams totally unaware of each other's work during data collection, suggests a high degree of reliability for this finding.

Leukaemia and residence near electricity transmission equipment: a case-control study

A population-based case-control study of leukaemia and residential proximity to electricity supply equipment has been carried out in south-east England. A total of 771 leukaemias was studied, matched for age, sex, year of diagnosis and district of residence to 1,432 controls registered with a solid tumour excluding lymphoma; 231 general population controls aged 18 and over from one part of the study area were also used. The potential for residential exposure to power frequency magnetic fields from power-lines and transformer substations was assessed indirectly from the distance, type and loading of the equipment near each subject's residence. Only 0.6% of subjects lived within 100 m of an overhead power-line, and the risk of leukaemia relative to cancer controls for residence within 100 m was 1.45 (95% confidence interval (CI) 0.54-3.88); within 50 m the relative risk was 2.0 but with a wider confidence interval (95% CI 0.4-9.0). Over 40% of subjects lived within 100 m of a substation, for which the relative risk of leukaemia was 0.99. Residence within 25 m carried a risk of 1.3 (95% CI 0.8-2.0). Weighted exposure indices incorporating measures of the current load carried by the substations did not materially alter these risks estimates. For persons aged less than 18 the relative risk of leukaemia from residence within 50 m of a substation was higher than in adults (PR = 1.5, 95% CI 0.7-3.4).

Radiation dose and breast cancer risk in patients treated for cancer of the cervix

The relationship between breast cancer and radiation treatment for cervical cancer was evaluated in an international study of 953 women who subsequently developed breast cancer and 1,806 matched controls. Radiation doses to the breast (average 0.31 Gy) and ovaries (average 32 Gy) were reconstructed for exposed subjects on the basis of their original radiotherapy records. Overall, 88% of the breast cancer cases and 89% of the controls received radiation treatment [relative risk (RR) = 0.88; 95% confidence interval (CI) = 0.7-1.2]. Among women with intact ovaries (561 cases, 1,037 controls), radiotherapy was linked to a significant 35% reduction in breast cancer risk, attributable in all likelihood to the cessation of ovarian function. Ovarian doses of 6 Gy were sufficient to reduce breast cancer risk but larger doses did not reduce risk further. This saturation-type response is probably due to the killing of a critical number of ovarian cells. Cervical cancer patients without ovaries (145 cases, 284 controls) were analyzed separately because such women are at especially low natural risk for breast cancer development. In theory, any effect of low-dose breast exposure, received incidentally during treatment for cervical cancer, should be more readily detectable. Among women without ovaries, there was a slight increase in breast cancer risk (RR = 1.07; 95% CI = 0.6-2.0), and a suggestion of a dose response with the RR being 1.0, 0.7, 1.5 and 3.1 for breast doses of 0, 0.01-0.24, 0.25-0.49 and 0.50+ Gy, respectively. However, this trend of increasing RR was not statistically significant. If low-dose radiation increases the risk of breast cancer among women over age 40 years, it appears that the risk is much lower than would be predicted from studies of younger women exposed to higher doses.

Radiation dose and leukemia risk in patients treated for cancer of the cervix

To quantify the risk of radiation-induced leukemia and provide further information on the nature of the relationship between dose and response, a case-control study was undertaken in a cohort of over 150,000 women with invasive cancer of the uterine cervix. The cases either were reported to one of 17 population-based cancer registries or were treated in any of 16 oncologic clinics in Canada, Europe, and the United States. Four controls were individually matched to each of 195 cases of leukemia on the basis of age and calendar year when diagnosed with cervical cancer and survival time. Leukemia diagnoses were verified by one hematologist. Radiation dose to active bone marrow was estimated by medical physicists on the basis of the original radiotherapy records of study subjects. The risk of chronic lymphocytic leukemia, one of the few malignancies without evidence for an association with ionizing radiation, was not increased [relative risk (RR) = 1.03; n = 52]. However, for all other forms of leukemia taken together (n = 143), a twofold risk was evident (RR = 2.0; 90% confidence interval = 1.0-4.2). Risk increased with increasing radiation dose until average doses of about 400 rad (4 Gy) were reached and then decreased at higher doses. This pattern is consistent with experimental data for which the down-turn in risk at high doses has been interpreted as due to killing of potentially leukemic cells. The dose-response information was modeled with various RR functions, accounting for the nonhomogeneous distribution of radiation dose during radiotherapy. The local radiation doses to each of 14 bone marrow compartments for each patient were incorporated in the models, and the corresponding risks were summed. A good fit to the observed data was obtained with a linear-exponential function, which included a positive linear induction term and a negative exponential term. The estimate of the excess RR per rad was 0.9%, and the estimated RR at 100 rad (1 Gy) was 1.7. The model proposed in this study of risk proportional to mass exposed and of risk to an individual given by the sum of incremental risks to anatomic sites appears to be applicable to a wide range of dose distributions. Furthermore, the pattern of leukemia incidence associated with different levels of radiation dose is consistent with a model postulating increasing risk with increasing exposure, modified at high doses by increased frequency of cell death, which reduces risk.

Aetiological factors in cutaneous malignant melanomas seen at a UK skin clinic

A clinic-based case-control study was set up in 1961 to examine a variety of aetiological factors in malignant melanoma cases compared with controls with other non-malignant skin conditions. The 268 cases and 1577 controls showed odds ratios of 1.9 for red hair, 2.0 for skin that burns in the sun, and no difference between indoor and outdoor workers or between Celts and other Europeans, consistent with the results of more recent studies. Exposure to 16 specific chemicals was recorded in the study and, among these, men exposed to cutting oils were found to have a significantly raised odds ratio of 1.91. Other statistically significant findings were an elevated risk among women diabetics, particularly in the postmenopausal age group, and a reduced risk of 0.7 among cigarette smokers.

Models of the healthy worker effect in industrial cohorts

The patterns of standardized mortality ratios (SMRs) with duration of follow-up and duration of service which are characteristic of the healthy worker effect in occupational cohort studies have been simulated using models of selection and survivor effects. The models support current theories about the population dynamics which underlie the selection effect but highlight inadequacies in our understanding of the survivor effect. Several possible models were tested and methods of generating appropriate data are discussed. It is important that the healthy worker effect should be better understood as it can present so large a problem in the interpretation of occupational risk estimates.

Second primary malignancy after Hodgkin's disease, ovarian cancer and cancer of the testis: a population-based cohort study

The risk of second primary malignancy was assessed in a population-based cohort study of all persons registered with Hodgkin's disease (n = 2,970), ovarian cancer (n = 11,802) and testicular cancer (n = 2,013) in the South Thames Cancer Registry during the period 1961-80, to identify for further study those second malignancies which might be treatment-related. A total of 244 second malignancies was observed. After adjustment for age, sex and calendar period, the relative risk of any second malignancy was 1.4 (90% confidence interval (CI) 1.1-1.7) after Hodgkin's disease, 1.1 (90% CI 1.0-1.2) after ovarian cancer and 0.7 (90% CI 0.5-1.0) after testicular cancer. In particular, the relative risk for leukaemia was 11.9 after Hodgkin's disease, 3.7 after ovarian cancer and 2.5 after testicular cancer. Excess risks were also observed for cancers of the cervix and lung after Hodgkin's disease, for cancers of the breast, lung and rectum after ovarian cancer, and for contralateral testicular cancer. Confounding by social class or smoking does not explain these observations. The excess risks of leukaemia and of second cancer were higher in patients first diagnosed with Hodgkin's disease and ovarian cancer in the 1970s than for those first diagnosed in the 1960s. Increased use of multiple-agent chemotherapy regimes for these tumours in the 1970s may have contributed to these increases in excess risk.

Lectin binding to psoriatic epidermis

The lectin-binding properties of psoriatic epidermis were assessed using a wide range of lectins. Changes in these properties were found at all levels of differentiation in lesional tissue. There was no clear evidence for an expansion in the population of basal-type cells. Binding of some lectins demonstrated a normal basal-suprabasal boundary. Others bound closer to the dermal-epidermal junction than in normal tissue, and expression of certain normal suprabasal characteristics was found in the basal layer in psoriasis. These findings suggest that the detected changes in psoriatic glycoconjugates reflect a programme of differentiation which is altered rather than incomplete.

Factors affecting the binding of lectins to normal human skin

Factors affecting the binding of a wide range of lectins to normal human skin were examined in order to evaluate current discrepancies in the literature. The profile of specific binding characteristic for each lectin was found to be variously influenced by the source of conjugate, tissue-processing method, the effectiveness of saccharide inhibitors, and by individual and minor body site variations. Most significantly, the use of routine histological processing not only greatly reduced binding intensity overall but also altered the binding pattern.

Abnormal pattern of erythrocyte ageing in hereditary spherocytosis as shown by Percoll density gradient centrifugation

Erythrocytes from individuals with Hereditary Spherocytosis (HS) were fractionated on Percoll density gradients. The osmotic fragility, mean cell volume, mean cell haemoglobin concentration, reticulocyte count and cell morphology of the fractions showed that the gradients separate the erythrocytes according to age, the older small spherocytes appearing in the dense fractions. Comparison of the well established parameters of erythrocyte ageing, pyruvate kinase activity, acetylcholinesterase activity and cell potassium content in normal and HS erythrocyte fractions of similar age revealed abnormalities in the senescence of HS erythrocytes both before and after splenectomy.

The release rate of 37Ar from human subjects following intravenous injection

Two measurements of the exhalation rate of 37Ar following an intravenous bolus injection have been made on a volunteer, and compared with the exhalation rate of 133Xe for the same subject. The results are also compared with a previously reported pilot 37Ar injection study on a second volunteer. During the first 100 min following injection, the 37Ar washout rate was shown to resemble closely the 133Xe washout rate. This result shows that for short time periods after injection, the behaviour of 133Xe may be used to predict 37Ar behaviour.

Predicted mortality patterns in cohort study populations exposed to different types of hazard: can SMRs show a dose-response?

The analysis of data from cohort studies by duration of exposure and time since first exposure (latent interval) has been investigated using a simulation approach. These two analyses are often performed when the estimator of risk, commonly the O/E ratio or SMR, shows evidence of a raised risk. Two measures of risk were tested in the detailed analyses: the O/E ratio and the excess death rate. The latter was found to reflect the 'dose-response' relationship more accurately for a variety of hazard types. Attention is drawn to possible biases and to the importance of adjustment for age in these analyses.

The retention and release of 37Ar from samples of human bone examined in vitro and a review of the implications for argon transfer from bone in vivo

The release rates and long term retention of 37Ar produced by the reaction 40Ca(n, alpha) 37Ar, following fast neutron irradiation, have been measured in vitro, in three samples of dried human femur. For each sample, the release rates were fitted to three exponential curves, of half-times approximately 2, 20 and 300 min. Some 60-80% of the 37Ar released was contained in the first component. The release rates for samples of trabecular and cortical bone were qualitatively similar, but after some 20 h the retained fraction of 37Ar was 28 +/- 0.6% in a sample of predominantly trabecular bone, and 33 +/- 0.7% in samples of predominantly cortical bone. The processes affecting the trapping and release of 37Ar from bone crystals are discussed. It is suggested that 37Ar escapes from bone mineral by back-diffusion along recoil damage tracks. The factors affecting the release of 37Ar from bone into the venous blood supply are discussed in the context of in vivo measurements of body calcium by the 37Ar method. The physiological processes and compartments likely to give rise to the long 37Ar exhalation half-times following irradiation in vivo: transfer from the mineralised bone matrix to blood capillaries, and uptake and washout from bone marrow, are considered. Uptake in bone marrow may be responsible for both of the observed half-times.

In vivo measurement of calcium by the 37Ar method: a study of the effect of recirculating breath collection systems on the exhalation rate

A study has been made of the effect that different methods of breath collection have on the measurement of calcium in vivo by the 40Ca(n,alpha) 37Ar method. The effect of open and rebreathing breath collection methods has been examined by using intravenous injections of 133Xe. This study has indicated that comparison of calcium measurements between individuals and between centres is likely to be accurate only if breath is collected on 'open circuit'.

Problems in the interpretation of the in vivo measurement of calcium by the argon-37 method: an investigation of inert-gas elimination in humans

An investigation has been made of some physiological problems associated with the interpretation of in-vivo measurements of calcium by the argon-37 method. Inert-gas elimination in humans over a period of several days was studied using i.v. injections of Xe-133. The results imply that the exhalation rate of A-37 formed in bone will be affected by the individual's composition, in particular body fat. Comparison of calcium measurements between individuals and between laboratories is meaningful only if corrections are made for differing individual composition.