Effect of varying dispenser point source density on mating disruption of Grapholita molesta (Lepidoptera: Tortricidae)

Hand-applied dispensers are successfully used in mating disruption programs, but cost of labor to apply these dispensers limits their adoption. Creating hand-applied dispensers that release larger amounts of pheromone and that can be applied at lower densities per hectare could reduce the cost of mating disruption and increase its use. The effect of reducing the number of point sources per hectare while keeping the amount of pheromone applied per hectare constant on the success of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) mating disruption was investigated with Confuse-OFM, paraffin disk, and Isomate-M Rosso dispensers. For all dispensers, as point source density decreased, numbers of moths captured increased, percentage of orientation disruption to traps decreased, and variability in these measures increased. Decreasing point source density, even while keeping the amount of pheromone applied per hectare constant is not a viable option for reducing the cost of G. molesta mating disruption with hand-applied dispensers. Puffers (aerosol dispensers) are applied at 2.5-5 dispensers per ha for G. molesta control. However, hand-applied dispensers fail when clumped at such low numbers of release sites. Potential explanations for the success of Puffers and the failure of hand-applied dispensers at very low point source densities are presented. The utility of paraffin disk dispensers as experimental devices also is discussed.

Endovascular versus open repair of abdominal aortic aneurysm

BACKGROUND

Few data are available on the long-term outcome of endovascular repair of abdominal aortic aneurysm as compared with open repair.

METHODS

From 1999 through 2004 at 37 hospitals in the United Kingdom, we randomly assigned 1252 patients with large abdominal aortic aneurysms (> or = 5.5 cm in diameter) to undergo either endovascular or open repair; 626 patients were assigned to each group. Patients were followed for rates of death, graft-related complications, reinterventions, and resource use until the end of 2009. Logistic regression and Cox regression were used to compare outcomes in the two groups.

RESULTS

The 30-day operative mortality was 1.8% in the endovascular-repair group and 4.3% in the open-repair group (adjusted odds ratio for endovascular repair as compared with open repair, 0.39; 95% confidence interval [CI], 0.18 to 0.87; P=0.02). The endovascular-repair group had an early benefit with respect to aneurysm-related mortality, but the benefit was lost by the end of the study, at least partially because of fatal endograft ruptures (adjusted hazard ratio, 0.92; 95% CI, 0.57 to 1.49; P=0.73). By the end of follow-up, there was no significant difference between the two groups in the rate of death from any cause (adjusted hazard ratio, 1.03; 95% CI, 0.86 to 1.23; P=0.72). The rates of graft-related complications and reinterventions were higher with endovascular repair, and new complications occurred up to 8 years after randomization, contributing to higher overall costs.

CONCLUSIONS

In this large, randomized trial, endovascular repair of abdominal aortic aneurysm was associated with a significantly lower operative mortality than open surgical repair. However, no differences were seen in total mortality or aneurysm-related mortality in the long term. Endovascular repair was associated with increased rates of graft-related complications and reinterventions and was more costly. (Current Controlled Trials number, ISRCTN55703451.)

Endovascular repair of aortic aneurysm in patients physically ineligible for open repair

BACKGROUND

Endovascular repair of abdominal aortic aneurysm was originally developed for patients who were considered to be physically ineligible for open surgical repair. Data are lacking on the question of whether endovascular repair reduces the rate of death among these patients.

METHODS

From 1999 through 2004 at 33 hospitals in the United Kingdom, we randomly assigned 404 patients with large abdominal aortic aneurysms (> or = 5.5 cm in diameter) who were considered to be physically ineligible for open repair to undergo either endovascular repair or no repair; 197 patients were assigned to undergo endovascular repair, and 207 were assigned to have no intervention. Patients were followed for rates of death, graft-related complications and reinterventions, and costs until the end of 2009. Cox regression was used to compare outcomes in the two groups.

RESULTS

The 30-day operative mortality was 7.3% in the endovascular-repair group. The overall rate of aneurysm rupture in the no-intervention group was 12.4 (95% confidence interval [CI], 9.6 to 16.2) per 100 person-years. Aneurysm-related mortality was lower in the endovascular-repair group (adjusted hazard ratio, 0.53; 95% CI, 0.32 to 0.89; P=0.02). This advantage did not result in any benefit in terms of total mortality (adjusted hazard ratio, 0.99; 95% CI, 0.78 to 1.27; P=0.97). A total of 48% of patients who survived endovascular repair had graft-related complications, and 27% required reintervention within the first 6 years. During 8 years of follow-up, endovascular repair was considerably more expensive than no repair (cost difference, 9,826 pounds sterling [U.S. $14,867]; 95% CI, 7,638 to 12,013 [11,556 to 18,176]).

CONCLUSIONS

In this randomized trial involving patients who were physically ineligible for open repair, endovascular repair of abdominal aortic aneurysm was associated with a significantly lower rate of aneurysm-related mortality than no repair. However, endovascular repair was not associated with a reduction in the rate of death from any cause. The rates of graft-related complications and reinterventions were higher with endovascular repair, and it was more costly. (Current Controlled Trials number, ISRCTN55703451.)

Abstract SY01-01: Adaptive protein and phosphoprotein networks which promote therapeutic sensitivity or acquired resistance

<abstract> Multiple signal transduction pathways can be concurrently active within a single cell, and extensive crosstalk can occur between RTKs. Additionally, tumor tissues can be comprised of a heterogeneous collection of cell states utilizing distinct RTKs for maintenance of tumor cell growth and survival. As a consequence of this complexity, many tumors may be only partially sensitive to single agent therapies and would require the interdiction of multiple RTKs and other protein signaling targets for optimal anti-cancer therapy. Understanding pathway crosstalk is vital to guide the rational combination of approved and experimental anti-cancer agents.

Receptor tyrosine kinases (RTKs) are key mediators of tumor cell survival, proliferation and migratory pathways, and inhibitors of RTKs have demonstrated anti-tumor efficacy in both the preclinical and clinical settings. Multiple sensitivity and resistance mechanisms have been described for EGF receptor inhibitors for the treatment of NSCLC. In carcinomas with an epithelial phenotype, onco-addiction and tumor progression have been associated with autocrine ligand-dependent activation of EGFR (1, 2). Notably, EGFR dependence can also occur through genetic mutations in exons 19-21 of the EGFR gene (3-5) which renders the encoded protein less able to bind ATP. Resistance can occur, primarily in these patients with these primary activating mutations, from acquisition of a secondary mutation of EGFR at the T790M gatekeeper site (6, 7) which increases ATP affinity and thereby decreases binding of ATP competitive inhibitors (8). Importantly, resistance can also occur through up regulation of alternate receptor tyrosine kinases (RTKs), and therefore understanding crosstalk between RTKs is critical for optimizing the use of RTK inhibitors in the clinic.

Tumor tissues progress from in situ to metastatic states through the reacquisition of developmental programs allowing invasion and metastasis. The acquisition of an invasive phenotype can occur by epithelial-mesenchymal transition (EMT). The molecular characteristics of epithelial and mesenchymal cell phenotypes were extensively characterized by intersection of proteomic, phosphoproteomic and gene expression profiling approaches. Tumor cells that have undergone EMT show a marked reduction in sensitivity to EGFR TKIs and anti-EGFR MAbs (9). In several instances, the EMT-derived mesenchymal-like tumor cells have gained sensitivity to PDGFR and/or FGFR1 inhibitors. Significant switching of receptor tyrosine kinases, from EGFR, Met/Ron and IGF-1R to cells utilizing PDGFR and FGFR was observed. The acquisition of autocrine fibronectin - integrin was also observed in several tumor lines and inducible models. Therefore, EMT can promote use of alternative signaling pathways.

Resistance can also derive from over activation of partially redundant pathways concurrently active in a cell. For example, activation of the IGF-1 receptor (IGF-1R) or the HGF receptor (Met) has been shown to obviate the need for EGFR signaling in epithelial-derived lung tumors (10). Crosstalk has been well documented with EGF, HGF and IGF1 receptors. These receptors, when activated by ligand binding, can create network redundancies (for example by IGF stimulation of EGFR onco-addicted cells; (11)). Reciprocal activation of one receptor following the inhibition of a distinct receptor has also been observed. For example PDGFRα was observed to be activated and substrates phosphorylated when EGFR was inhibited in the NSCLC line H1703(12). These studies involved a quantitative anti-phosphotyrosine profiling (13) coupled to an LC-MS/MS shotgun approach. In a second example in the Ewings sarcoma line A673, IGF-1R inhibition, by kinase inhibition resulted in the reciprocal activation of the insulin receptor and cell survival (14). We have previously shown reciprocal activation of EGFR by IGF1R inhibition and activation of IGF1R through EGFR inhibition (15). The mechanisms by which reciprocity is achieved are under investigation. The ability of tumor cells to reciprocally induce alternative RTKs following the inhibition of a given receptor (in this case EGFR or IGF1R) highlights the need for rational combination anti-cancer therapy.

One RTK may also positively affect the activity of another in a process that can be termed receptor co-option. Here, one dominant ligand-stimulated RTK, possibly amplified or mutated, directly or indirectly tyrosine phosphorylates additional RTKs to create functional signaling scaffolds and to engage signaling networks beyond the normal capabilities of the original dominant kinase. Where the co-option of RTK signaling networks is observed, markers of RTK activation (e.g. the extent of receptor tyrosine phosphorylation) are not necessarily predictive of onco-addiction. Direct or indirect crosstalk between EGFR, ErbB2, Met, Ron and other RTKs has been observed in a bidirectional manner. Crosstalk can occur on the RON Y1238/Y1239 autophosphorylation site where MET and/or EGFR are the active kinases. Such phosphorylation in trans (either direct or indirect) may promote RON kinase activity in the absence of ligand. Alternatively or in addition, cross phosphorylation of RTKs in trans can allow signaling scaffolds to be established, mimicking kinase activation in the absence of ligand. Three NSCLC models illustrate co-option of RTKs as described below:

The NSCLC line H1650 harbors a gain-of-function exon 19 deletion that is strongly onco-addicting in adenocarcinoma of the lung and is often associated with exquisite sensitivity to EGFR blockade. Pharmacological inhibition of EGFR in H1650 by the EGFR-ErbB2 inhibitor erlotinib results in a rapid dephosphorylation of ErbB2, Src family kinases and the direct and downstream substrates Cbl-B and Erk2 respectively. Interestingly attenuation of Met tyrosine phosphorylation is also observed suggesting that hyperactive mutant EGFR (del19) can also co-opt additional RTKs.

In the NSCLC line H292, ~50% of the tyrosine phosphate on Met and on Ron is inhibitable by EGFR blockade. Crosstalk between EGFR, Met and Ron kinases was measured by combined anti-phosphotyrosine immunoaffinity selection, stable isotope peptide labeling (iTRAQ) and LC-electrospray tandem MS. The phosphotyrosine content on Met and Ron was decreased following exposure to erlotinib relative to mock control cells. The inhibition of phospho-Met and phospho-Ron followed kinetics for the erlotinib-dependent decrease in the SH2 adapter proteins phospho-SHC, -Erk2 and Grb2. The data suggest either direct phosphorylation of Met and Ron by EGFR or rapid recruitment and activation of intermediary non-transmembrane tyrosine kinases. These non-transmembrane tyrosine kinases could include Src/Yes/Fyn family kinases or Brk family kinases, possibly in a cell-specific manner, but this remains to be tested.

A more extreme example of co-option of diverse kinase signaling networks by a single RTK is observed in the NSCLC H1993 cell line. Here exposure to small molecule Met tyrosine kinase inhibitors attenuated both Met and Met-associated SH2/PTB domain adapter proteins as well as more distantly related RTK signaling networks. Exposure of H1993 epithelial carcinoma cells to Met inhibitors markedly inhibited ~250 Met substrates, both known and unknown, including the cell surface signaling proteins Met, Ron, EGFR, ErbB2, DDR1, CSFR2, ITG4, ITG6, EphA2, EphB4. This in turn results in a comparatively complete dephosphorylation of a wide array of signaling adaptors, cell-cell junction proteins, cytoskeletal reorganizing elements and folding chaperones. While marked attenuation of EGFR was observed in response to Met inhibition alone, the combination of both Met and EGFR inhibitors was required for full dephosphorylation of both Erk1/2 and STAT5A. These findings suggest that while Met can co-opt EGFR, phosphorylate EGFR, and establish initial SH2/PTB domain dependent complexes on EGFR via active Met kinase, the extent of Met-dependent EGFR tyrosine phosphorylation is insufficient for full Erk and STAT5 activation. Several conclusions can be drawn. First, Met is the principle source of phosphotyrosine in H1993, and the cell line is likely onco-addicted solely to Met. Second, Met essentially ‘highjacks’ other RTKs as signaling adapters. Third, effective blockade of Erk activation was only observed with dual Met and EGFR inhibition suggesting synergy relies on erlotinib directed Erk inhibition in the H1993 model.

The quantitative measurement of cancer cell signaling under dynamic conditions of pharmacological or siRNA mediated inhibition of specific signaling nodes gives insight into the requirements for effective cellular blockade of survival and invasive networks associated with cancer progression. The use of quantitative shotgun LC-MS/MS methods incorporating stable isotopes provides a rapid means to identify proteins and phosphoproteins perturbed in particular cancer cell states. These methods have allowed interrogation of RTK crosstalk in tumor cell lines and xenografts so as to generate specific hypotheses relating to targeted drug combinations. In addition such data have better defined the role of EMT in survival signaling switching and anticancer drug resistance, again suggesting combination therapy options for further investigation.

References

1. Han et al Br J Cancer 2009.

2. Jacobs et al J Clin Oncol 2009.

3. Lynch et al N Engl J Med 2004.

4. Paez et al Science 2004.

5. Pao et al Proc Natl Acad Sci 2004.

6. Bell et al Nat Genet 2005.

7. Pao et al PLoS Med 2005.

8. Carey et al Cancer Res 2006.

9. Barr et al Clin Exp Metastasis 2008.

10. Engelman et al Science 2007.

1.1 Thelemann et al Mol Cell Proteomics 2005.

12. Thomson et al Clin Exp Metastasis 2008.

13. F. Petti et al Mol Cancer Ther 2005.

14. E. Buck manuscript submitted.

15. E. Buck et al Cancer Res 2008.

Citation Format: John D. Haley, Stuart Thomson, James Bean, Ruixi Xie, David Epstein, Mark Miglarese, Liz Buck. Adaptive protein and phosphoprotein networks which promote therapeutic sensitivity or acquired resistance [abstract]. In: Proceedings of the AACR 101st Annual Meeting 2010; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr SY01-01

Abstract 1654: Compensatory insulin receptor (IR) activation upon inhibition of insulin-like growth factor receptor (IGF-1R): Rationale for co-targeting IGF-1R and IR in cancer

The insulin-like growth factor receptor (IGF-1R) is a receptor tyrosine kinase (RTK) and a critical mediator of signaling through the PI3K-AKT pathway. IGF-1R is required for oncogenic transformation and tumorigenesis, and inhibiton of IGF-1R results in reduced proliferation and survival of tumor cells. These observations have spurred intense drug discovery and development efforts for both biologic and small molecule IGF-1R inhibitors for the treatment of cancer.

The ability for one RTK to compensate for another to maintain growth and survival signaling in tumor cells is emerging as a common mechanism of resistance to anti-tumor agents that selectively target individual RTKs. As IGF-1R is structurally and functionally related to the insulin receptor (IR), and IR can also activate tumor cell AKT signaling and cellular transformation, we asked whether IR signaling can contribute to resistance to IGF-1R inhibition in tumor cells.

In a panel of human tumor cell lines, IGF-1R/IR crosstalk was observed after treatment with a selective anti-IGF-1R monoclonal antibody, MAB391. Tumor cells treated with MAB391 responded with a compensatory increase in phospho-IR, which was also associated with an inability to fully inhibit phospho-IRS1 and phospho-AKT. In contrast, treatment with OSI-906, a small molecule dual kinase inhibitor of IGF-1R and IR, resulted in enhanced inhibition of the IRS1-AKT signaling pathway. OSI-906 showed superior efficacy compared to MAB391 in human tumor xenograft models where both phospho-IR and phospho-IGF-1R were detectable, and presumably both receptors were required by tumor cells for growth and/or survival. Both insulin and IGF-2 can activate the IR-AKT pathway and we show that treatment with either growth factor resulted in decreased sensitivity of tumor cells to MAB391, but not OSI-906. In tumor cells with an autocrine IGF-2 signaling loop, both OSI-906 and an anti-IGF-2 neutralizing antibody reduced phospho-IR and phospho-AKT levels, whereas MAB391 was ineffective. Collectively, these data indicate that OSI-906, which co-targets IGF-1R and IR, may provide superior efficacy as compared to agents that selectively target only IGF-1R.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1654.

Budgetary policies and available actions: a generalisation of decision rules for allocation and research decisions

The allocation problem in health care can be characterised as a mathematical programming problem but attempts to incorporate uncertainty in costs and effect have suffered from important limitations. A two-stage stochastic mathematical programming formulation is developed and applied to a numerical example to explore and demonstrate the implications of this more general and comprehensive approach. The solution to the allocation problem for different budgets, budgetary policies, and available actions are then demonstrated. This analysis is used to evaluate different budgetary policies and examine the adequacy of standard decision rules in cost-effectiveness analysis. The research decision is then considered alongside the allocation problem. This more general formulation demonstrates that the value of further research depends on: (i) the budgetary policy in place; (ii) the realisations revealed during the budget period; (iii) remedial actions that may be available; and (iv) variability in parameters values.

Abstract A46: Pharmacodynamic biomarkers for OSI-906, an insulin-like growth factor-1 receptor (IGF-1R) tyrosine kinase inhibitor, in cancer patients with advanced solid tumors

Background: OSI-906 is a potent small molecule inhibitor of the insulin-like growth factor 1 receptor (IGF-1R), a receptor tyrosine kinase that is overexpressed in several human cancer types and implicated in resistance to chemotherapy. Disruption of the growth hormone-IGF1 signaling axis can affect levels of biomarkers such as IGF1, growth hormone (GH) and insulin and can affect glucose homeostasis, making these potentially useful markers for demonstrating the activity of IGF-1R inhibitors in solid tissues.

Methods: Two phase I dose escalation trials were initiated in cancer patients with advanced solid tumors who received OSI-906 on either continuous or intermittent dosing schedules. Pharmacodynamic (PD) and pharmacokinetic (PK) assessments were included as secondary objectives of these studies. Circulating biomarkers, including total IGF1, IGFBP3 and non-fasting GH and insulin levels, were measured at various times during the dosing cycle (21 days for continuous dosing; 14 days for intermittent dosing) and changes were correlated with plasma concentrations of OSI-906.

Results: To date, patients have been treated with up to 450 mg QD and 200 mg BID on the continuous dosing schedule and up to 750 mg QD on the intermittent dosing schedule. Maximum tolerated dose (MTD) was determined to be 400 mg QD and 150 mg BID for continuous dosing and 600 mg QD for intermittent dosing. Preliminary analysis of the PK data suggests that the exposure of OSI-906 increased with dose. Median plasma concentrations of OSI-906 at MTD exceeded the predicted concentration required for efficacy based on the preclinical models (1 µM). Total IGF1 concentrations in plasma were increased relative to predose levels at doses ≥ 450 mg QD on the intermittent dosing schedule and ≥ 150 mg QD or 40 mg BID on the continuous dosing schedule. Elevations in non-fasting plasma insulin levels were also observed in patients with plasma concentrations of OSI-906 exceeding 5000 ng/mL. PK/PD relationships were observed for IGF1 and insulin. OSI-906 did not affect plasma IGFBP3 levels in most patients. Analysis of additional biomarkers, including GH, is ongoing.

Conclusions: At or below MTD, plasma concentrations of OSI-906 could be achieved that exceed concentrations required for anti-tumor efficacy based on the preclinical models. The pharmacodynamic data indicate that pharmacologically-relevant concentrations of OSI-906 were achieved in tissues involved in regulating the GH-IGF1 signaling axis. Together, these PK and PD data indicate that the current recommended dosing regimens may provide sufficient exposure for activity against solid tumors.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A46.

Laparoscopic fundoplication compared with medical management for gastro-oesophageal reflux disease: cost effectiveness study

OBJECTIVE

To describe the long term costs, health benefits, and cost effectiveness of laparoscopic surgery compared with those of continued medical management for patients with gastro-oesophageal reflux disease (GORD).

DESIGN

We estimated resource use and costs for the first year on the basis of data from the REFLUX trial. A Markov model was used to extrapolate cost and health benefit over a lifetime using data collected in the REFLUX trial and other sources.

PARTICIPANTS

The model compared laparoscopic surgery and continued proton pump inhibitors in male patients aged 45 and stable on GORD medication.

INTERVENTION

Laparoscopic surgery versus continued medical management.

MAIN OUTCOME MEASURES

We estimated quality adjusted life years and GORD related costs to the health service over a lifetime. Sensitivity analyses considered other plausible scenarios, in particular size and duration of treatment effect and the GORD symptoms of patients in whom surgery is unsuccessful. Main results The base case model indicated that surgery is likely to be considered cost effective on average with an incremental cost effectiveness ratio of pound2648 (euro3110; US$4385) per quality adjusted life year and that the probability that surgery is cost effective is 0.94 at a threshold incremental cost effectiveness ratio of pound20 000. The results were sensitive to some assumptions within the extrapolation modelling.

CONCLUSION

Surgery seems to be more cost effective on average than medical management in many of the scenarios examined in this study. Surgery might not be cost effective if the treatment effect does not persist over the long term, if patients who return to medical management have poor health related quality of life, or if proton pump inhibitors were cheaper. Further follow-up of patients from the REFLUX trial may be valuable.

TRIAL REGISTRATION

ISRCTN15517081.

Social determinants of health: an economic perspective

The World Health Organization has recently received the findings of its Commission on the Social Determinants of Health. The Commission's report offers a remarkable summary of the evidence, and makes a passionate case for government action to address the social determinants of health, especially as they relate to health inequity. This paper summarizes the ways in which economic analysis could strengthen policy under three headings: examining the causal impact of the determinants of health and of associated policies; prioritizing actions; and determining the role of government in influencing behaviour.

Stapled haemorrhoidopexy for the treatment of haemorrhoids: a systematic review

OBJECTIVE

This systematic review aimed to evaluate the short- and long-term safety, efficacy and costs of stapled haemorrhoidopexy (SH) compared with conventional haemorrhoidectomy.

METHOD

We searched 26 electronic databases and websites for studies in any language up to July 2006. Inclusion criteria were predefined, and each stage of the review process was conducted in duplicate.

RESULTS

Twenty-seven randomized controlled trials were included (n = 2279). All had some methodological flaws. Postoperatively, 19 trials (95%) reported less pain, 17 (89%) reported a shorter operating time, 14 (88%) a shorter hospital stay, and 14 (93%) a shorter convalescence time following SH. However, prolapse was significantly more common after SH (OR 3.38; 95% CI: 1.00, 11.47). In the longer term, prolapse was significantly more common after SH (OR 4.34; 95% CI: 1.67, 11.28) as was reintervention for prolapse (OR 6.78; 95% CI: 2.00, 23.00). There were no differences in the rate or type of complications. Conventional haemorrhoidectomy and SH had similar costs during the initial admission.

CONCLUSION

Compared with conventional haemorrhoidectomy, SH resulted in less postoperative pain, shorter operating time, a shorter hospital stay, and a shorter convalescence, but a higher rate of prolapse and reintervention for prolapse.

Modelling the cost-effectiveness of first, second and third generation polychemotherapy regimens in women with early breast cancer who have differing prognoses

Abstract #6106

Purpose: To use individual patient data from three sequential large UK randomised trials to facilitate an integrated comparison of the cost-effectiveness of three generations of chemotherapy plus a no treatment option. The ABC trial compared CMF versus no chemo (1991 patients), NEAT trial Epirubicin-CMF versus CMF (2391 patients) and TACT FEC-Docetaxel vs FEC or epi-CMF (4162 patients)
 Methods: The model estimates lifetime costs and Quality-Adjusted Life Years (QALYs). Model inputs include transition probabilities which are estimated from a longitudinal observational study using parametric survival models incorporating characteristics such as number of positive lymph nodes, ER status, grade and tumour size that allow analyses to be conducted for women with differing baseline prognoses. The effects of each chemotherapy regimen on preventing recurrence are taken from the above UK trials and are assumed to be additive on the log scale to facilitate previously untested comparisons. Costs and utility decrements associated with chemotherapy, its toxicity, and type of recurrent disease, are informed from the trial data and published literature. A secondary analysis is performed by basing the effects of each chemotherapy regimen on published meta-analyses based on individual level data that include RCTs conducted in a range of multi-national settings.
 Results: For a woman aged 50 years with 1 positive node, grade 2 tumour size 2cm, ECMF is expected to be the most cost-effective regimen. However, the cost-effectiveness of the chemotherapy options varies between women with different risk factors. On the basis of the results of the TACT trial, 3rd generation chemotherapy is not cost-effective, but including evidence of the relative risk of recurrence from non-UK trials, particularly those with ER- and HER2+ phenotype, may alter this conclusion.
 Indicative lifetime costs and QALYs for a woman aged 50 years, with 1 positive node, grade 2 tumor size 2cm, with and without ER+ are shown:
 
 
 
 Conclusions: Evaluating the cost-effectiveness of chemotherapy regimens in women with early breast cancer who have differing prognoses is feasible using an integrative synthesis and model. Thought does, however, need to be given to how best present cost-effectiveness results when there are differing levels of baseline risk.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6106.

The effectiveness and cost-effectiveness of minimal access surgery amongst people with gastro-oesophageal reflux disease - a UK collaborative study. The REFLUX trial

OBJECTIVES

To evaluate the clinical effectiveness, cost-effectiveness and safety of a policy of relatively early laparoscopic surgery compared with continued medical management amongst people with gastro-oesophageal reflux disease (GORD) judged suitable for both policies.

DESIGN

Relative clinical effectiveness was assessed by a randomised trial (with parallel non-randomised preference groups) comparing a laparoscopic surgery-based policy with a continued medical management policy. The economic evaluation compared the cost-effectiveness of the two management policies in order to identify the most efficient provision of future care and describe the resource impact that various policies for fundoplication would have on the NHS.

SETTING

A total of 21 hospitals throughout the UK with a local partnership between surgeon(s) and gastroenterologist(s) who shared the secondary care of patients with GORD.

PARTICIPANTS

The 810 participants, who were identified retrospectively or prospectively via their participating clinicians, had both documented evidence of GORD (endoscopy and/or manometry/24-hour pH monitoring) and symptoms for longer than 12 months. In addition, the recruiting clinician(s) was clinically uncertain about which management policy was best.

INTERVENTION

Of the 810 eligible patients who consented to participate, 357 were recruited to the randomised arm of the trial (178 allocated to surgical management, 179 allocated to continued, but optimised, medical management) and 453 recruited to the parallel non-randomised preference arm (261 chose surgical management, 192 chose to continue with best medical management). The type of fundoplication was left to the discretion of the surgeon.

MAIN OUTCOME MEASURES

Participants completed a baseline REFLUX questionnaire, developed specifically for this study, containing a disease-specific outcome measure, the Short Form with 36 Items (SF-36), the EuroQol-5 Dimensions (EQ-5D) and the Beliefs about Medicines and Surgery questionnaires (BMQ/BSQ). Postal questionnaires were completed at participant-specific time intervals after joining the trial (equivalent to approximately 3 and 12 months after surgery). Intraoperative data were recorded by the surgeons and all other in-hospital data were collected by the research nurse. At the end of the study period, participants completed a discrete choice experiment questionnaire.

RESULTS

The randomised groups were well balanced at entry. Participants had been taking GORD medication for a median of 32 months; the mean age of participants was 46 years and 66% were men. Of 178 randomised to surgery, 111 (62%) actually had fundoplication. There was a mixture of clinical and personal reasons why some patients did not have surgery, sometimes related to long waiting times. A total or partial wrap procedure was performed depending on surgeon preference. Complications were uncommon and there were no deaths associated with surgery. By the equivalent of 12 months after surgery, 38% in the randomised surgical group (14% amongst those who had surgery) were taking reflux medication compared with 90% in the randomised medical group. There were substantial differences (one-third to one-half standard deviation) favouring the randomised surgical group across the health status measures, the size depending on assumptions about the proportion that actually had fundoplication. These differences were the same or somewhat smaller than differences observed at 3 months. The lower the REFLUX score, the worse the symptoms at trial entry and the larger the benefit observed after surgery. The preference surgical group had the lowest REFLUX scores at baseline. These scores improved substantially after surgery, and by 12 months they were better than those in the preference medical group. The BMQ/BSQ and discrete choice experiment did distinguish the preference groups from each other and from the randomised groups. The latter indicated that the risk of serious complications was the most important single attribute of a treatment option. A within-trial cost-effectiveness analysis suggested that the surgery policy was more costly (mean 2049 pounds) but also more effective [+0.088 quality-adjusted life-years (QALYs)]. The estimated incremental cost per QALY was 19,000-23,000 pounds, with a probability between 46% (when 62% received surgery) and 19% (when all received surgery) of cost-effectiveness at a threshold of 20,000 pounds per QALY. Modelling plausible longer-term scenarios (such as lifetime benefit after surgery) indicated a greater likelihood (74%) of cost-effectiveness at a threshold of 20,000 pounds, but applying a range of alternative scenarios indicated wide uncertainty. The expected value of perfect information was greatest for longer-term quality of life and proportions of surgical patients requiring medication.

CONCLUSIONS

Amongst patients requiring long-term medication to control symptoms of GORD, surgical management significantly increases general and reflux-specific health-related quality of life measures, at least up to 12 months after surgery. Complications of surgery were rare. A surgical policy is, however, more costly than continued medical management. At a threshold of 20,000 pounds per QALY it may well be cost-effective, especially when putative longer-term benefits are taken into account, but this is uncertain. The more troublesome the symptoms, the greater the potential benefit from surgery. Uncertainty about cost-effectiveness would be greatly reduced by more reliable information about relative longer-term costs and benefits of surgical and medical policies. This could be through extended follow-up of the REFLUX trial cohorts or of other cohorts of fundoplication patients.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN15517081.

Economic evaluation of coronary artery bypass grafting surgery with and without cardiopulmonary bypass: cost-effectiveness and quality-adjusted life years in a randomized controlled trial

The objective of this study is to evaluate the costs and health benefits of coronary artery bypass grafting (CABG) surgery with and without cardiopulmonary bypass (CPB). Randomized controlled clinical trial is used as the design. The setting is in a single tertiary cardiothoracic center in Middlesex, UK. Participants were 168 patients (27 females) requiring primary isolated CABG surgery. Patients were randomized to have the procedure performed by a single surgeon either with CPB (n = 84) or by an off-pump coronary artery bypass (OPCAB) surgery (n = 84). Health-related quality of life was assessed at baseline, 6 weeks, and 6 months using the World Health Organization Quality-of-Life (WHOQOL-100) questionnaire. Mean total costs of patient management by either technique were calculated using different available key sources. A utility measure, derived from WHOQOL-100, was used to calculate quality-adjusted life year (QALY) gained in each group, on basis of which a cost-effectiveness analysis was performed. The mean total costs of an OPCAB patient was 5859 pounds , whereas for a CPB patient it was 7431 pounds with a mean difference of 1572 pounds (standard error [SE] 674 pounds ; P = 0.02). Three patients died in the CPB group and two in the OPCAB group during the 6-month follow-up period. Mean QALYs over 6 months was 0.379 in the OPCAB group and 0.362 in the CPB group, but the difference was not significant (mean difference 0.017; SE 0.016; P = 0.305). OPCAB surgery offered patients in this randomized trial similar health benefits to CPB over a 6-month period, but at a significantly less cost.

Acute acromioclavicular injuries in adults

The acromioclavicular joint is comprised of the articulation between the distal end of the clavicle and the acromion. It functions to anchor the clavicle to the scapula and to the shoulder girdle. The subcutaneous location of this joint makes it vulnerable to injury. It comprises approximately 9% of all injuries to the shoulder girdle. The majority of these injuries occur in males with a male to female ratio of approximately 5:1, and the most common age group affected are those in their 20s. Injuries to the acromioclavicular joint are prevalent in football, rugby, and other contact sports. Given the high incidence of acromioclavicular injuries, it is common for orthopedists, emergency physicians, and physical therapists to recognize and initiate treatment for the full spectrum of this type of injury. The current literature outlines joint biomechanics, various methods of fixation, and outcomes of both nonoperative and operative therapy. This article reviews the anatomy, biomechanics, classification of injury, fixation techniques, and outcomes.

Feedback mechanisms promote cooperativity for small molecule inhibitors of epidermal and insulin-like growth factor receptors

Epidermal growth factor receptor (EGFR) and insulin-like growth factor-I receptor (IGF-IR) can cooperate to regulate tumor growth and survival, and synergistic growth inhibition has been reported for combined blockade of EGFR and IGF-IR. However, in preclinical models, only a subset of tumors exhibit high sensitivity to this combination, highlighting the potential need for patient selection to optimize clinical efficacy. Herein, we have characterized the molecular basis for cooperative growth inhibition upon dual EGFR and IGF-IR blockade and provide biomarkers that seem to differentiate response. We find for epithelial, but not for mesenchymal-like, tumor cells that Akt is controlled cooperatively by EGFR and IGF-IR. This correlates with synergistic apoptosis and growth inhibition in vitro and growth regression in vivo upon combined blockade of both receptors. We identified two molecular aspects contributing to synergy: (a) inhibition of EGFR or IGF-IR individually promotes activation of the reciprocal receptor; (b) inhibition of EGFR-directed mitogen-activated protein kinase (MAPK) shifts regulation of Akt from EGFR toward IGF-IR. Targeting the MAPK pathway through downstream MAPK/extracellular signal-regulated kinase kinase (MEK) antagonism similarly promoted IGF-driven pAkt and synergism with IGF-IR inhibition. Mechanistically, we find that inhibition of the MAPK pathway circumvents a negative feedback loop imposed on the IGF-IR- insulin receptor substrate 1 (IRS-1) signaling complex, a molecular scenario that parallels the negative feedback loop between mTOR-p70S6K and IRS-1 that mediates rapamycin-directed IGF-IR signaling. Collectively, these data show that resistance to inhibition of MEK, mTOR, and EGFR is associated with enhanced IGF-IR-directed Akt signaling, where all affect feedback loops converging at the level of IRS-1.

Stapled haemorrhoidectomy (haemorrhoidopexy) for the treatment of haemorrhoids: a systematic review and economic evaluation

OBJECTIVES

To determine the safety, clinical effectiveness and cost-effectiveness of circular stapled haemorrhoidopexy (SH) for the treatment of haemorrhoids.

DATA SOURCES

Main electronic databases were searched up to July 2006.

REVIEW METHODS

Randomised controlled trials (RCTs) with 20 or more participants that compared SH with any conventional haemorrhoidectomy (CH) technique in people of any age with prolapsing haemorrhoids for whom surgery is considered a relevant option, were used to evaluate clinical effectiveness. An economic model of the surgical treatment of haemorrhoids was developed.

RESULTS

The clinical effectiveness review included 27 RCTs (n = 2279; 1137 SH; 1142 CH). All had some methodological flaws; only two reported recruiting patients with second, third and fourth degree haemorrhoids, and 37% reported using an appropriate method of randomisation and/or allocation concealment. In the early postoperative period 95% of trials reported less pain following SH; by day 21 the pain reported following SH and CH was minimal, with little difference between the two techniques. Significantly fewer patients had unhealed wounds at 6 weeks following SH [odds ratio (OR) 0.08, 95% confidence interval (CI) 0.03 to 0.19, p < 0.001]. Residual prolapse was more common after SH (OR 3.38, 95% CI 1.00 to 11.47, p = 0.05, nine RCTs, results of a sensitivity analysis). There was no difference between SH and CH in the incidence of bleeding or postoperative complications. SH resulted in shorter operating times, hospital stay, time to first bowel movement and return to normal activity. In the short term (between 6 weeks and a year) prolapse was more common after SH (OR 4.68, 95% CI 1.11 to 19.71, p = 0.04, six RCTs). There was no difference in the number of patients complaining of pain between SH and CH. In the long term (1 year and over), there was a significantly higher rate of prolapse after SH (OR 4.34, 95% CI 1.67 to 11.28, p = 0.003, 12 RCTs). There was no difference in the number of patients experiencing pain, or the incidence of bleeding, between SH and CH. There was no difference in the total number of reinterventions, or reinterventions for pain, bleeding or complications, between SH and CH. Significantly more reinterventions were undertaken after SH for prolapse at 12 months or longer (OR 6.78, 95% CI 2.00 to 23.00, p = 0.002, six RCTs). Overall, there was no statistically significant difference in the rate of complications between SH and CH. In the economic assessment it was found that, on average, CH dominated SH. However, CH and SH had very similar costs and quality-adjusted life-years (QALYs). On average, the difference in costs between the procedures was 19 pounds and the difference in QALY was -0.001, favouring CH, over 3 years. In terms of QALYs, the superior quality of life due to lower pain levels in the early postoperative period with SH was offset by the higher rate of symptoms over the follow-up period, compared with CH. The results are very sensitive to modelling assumptions, particularly the valuation of utility in the early postoperative period. The probabilistic sensitivity analysis showed that, at a threshold incremental cost-effectiveness ratio of 20,000-30,000 pounds per QALY, SH had a 45% probability of being cost-effective.

CONCLUSIONS

SH was associated with less pain in the immediate postoperative period, but a higher rate of residual prolapse, prolapse in the longer term and reintervention for prolapse. There was no clear difference in the rate or type of complications associated with the two techniques and the absolute and relative rates of recurrence and reintervention for both are still uncertain. CH and SH had very similar costs and QALYs, the cost of the staple gun being offset by savings in hospital stay. Should the price of the gun change, the conclusions of the economic analysis may also change. Some training may be required in the use of the staple gun; this is not expected to have major resource implications. Given the currently available clinical evidence and the results of the economic analysis, the decision as to whether SH or CH is conducted could primarily be based on the priorities and preferences of the patient and surgeon. An adequately powered, good-quality RCT is required, comparing SH with CH, recruiting patients with second, third and fourth degree haemorrhoids, and having a minimum follow-up period of 5 years to ensure an adequate evaluation of the reintervention rate. Other areas for research are the effectiveness of SH in patients with fourth degree haemorrhoids and patients with co-morbid conditions, the reintervention rates for all treatments for haemorrhoids, utilities of patients up to 6 months postoperatively, the trade-offs of patients for short-term pain versus long-term outcomes, and the ability of SH to reduce hospital stays in a real practice setting.

Kinase switching in mesenchymal-like non-small cell lung cancer lines contributes to EGFR inhibitor resistance through pathway redundancy

NSCLC cells with a mesenchymal phenotype have shown a marked reduction in sensitivity to EGFR inhibitors, though the molecular rationale has remained obscure. Here we find that in mesenchymal-like tumor cells both tyrosine phosphorylation of EGFR, ErbB2, and ErbB3 signaling networks and expression of EGFR family ligands were decreased. While chronic activation of EGFR can promote an EMT-like transition, once having occurred EGFR family signaling was attenuated. We investigated the mechanisms by which mesenchymal-like cells bypass EGFR signaling and acquire alternative routes of proliferative and survival signaling. Mesenchymal-like NSCLC cells exhibit aberrant PDGFR and FGFR expression and autocrine signaling through these receptors can activate the MEK-ERK and PI3K pathways. Selective pharmacological inhibition of PDGFR or FGFR receptor tyrosine kinases reduced cell proliferation in mesenchymal-like but not epithelial NSCLC cell lines. A metastable, reversible EMT-like transition in the NSCLC line H358 was achieved by exogenous TGFbeta, which served as a model EMT system. The H358/TGFbeta cells showed many of the attributes of established mesenchymal-like NSCLC cells including a loss of cell-cell junctions, a loss of EGF-family ligand expression, a loss of ErbB3 expression, increased EGFR-independent Mek-Erk pathway activation and reduced sensitivity to EGFR inhibition. Notably an EMT-dependent acquisition of PDGFR, FGFR and TGFbeta receptors in H358/TGFbeta cells was also observed. In H358/TGFbeta cells both PDGFR and FGFR showed functional ligand stimulation of their intrinsic tyrosine kinase activities. The findings of kinase switching and acquired PDGFR and FGFR signaling suggest investigation of new inhibitor combinations to target NSCLC metastases.

[An economic assessment of genetic testing for familial adenomatous polyposis]

OBJECTIVE

To analyze the cost-effectiveness of genetic testing for first-degree relatives of patients with colon cancer to identify mutations in the APC gene (Adenomatous Polyposis Coli).

METHODOLOGY

Analyses were performed from the perspective of the health system. We used a Markov model. We compared genetic testing for the APC gene, the cause of familial adenomatous polyposis (FAP), which results in colon cancer, versus no genetic testing for said gene. The effectiveness measure used was quality-adjusted life-years (QALYs), and costs were measured in euros for 2005. The costs of interventions were extracted from the costs of health services provided by centers under the Andalusian Public Health System, and other parameters were obtained from the literature.

RESULTS

The performance of genetic testing is the dominant strategy when compared to the absence of genetic testing given the latter option has an incremental cost of 7,676.34 euros and is less effective. A sensitivity analysis found that genetic testing remains the dominant strategy for a plausible range of costs of the test itself, and for the probability of developing adenocarcinoma.

CONCLUSIONS

Our analysis showed that in this patient group genetic testing to detect APC gene mutations is on average less costly and improves QALYs versus no testing.

Longitudinal ECG changes in cocaine users during extended abstinence

BACKGROUND

Cocaine lengthens electrocardiographic QTc, QRS and PR intervals through blockade of sodium and potassium channels, but changes during withdrawal have not been well studied.

METHODS

We recorded weekly electrocardiograms (ECGs) from 25 physically healthy cocaine users (84.0% men, mean [S.D.] age 34.7 [4.1] years, 9.0 [5.2] years of cocaine use, 9.4 [3.5] days of use in the 2 weeks prior to admission) over 3 months of monitored abstinence on a closed ward. Subjects had minimal current use of other drugs. Baseline ECGs were recorded 20.5 h [16.6] after last cocaine use.

RESULTS

Baseline QTc interval correlated positively with total amount of cocaine used and amount used per day in the 2 weeks prior to ward admission. There was a significant 10.5 ms [12.9] shortening of QTc interval during the first week of withdrawal, with no further significant changes thereafter. There were no significant changes in PR or QRS intervals.

CONCLUSIONS

These findings suggest that cocaine-associated QTc prolongation returns toward normal during the first week of cocaine abstinence.

The hospital costs of care for stroke in nine European countries

Stroke is a major cause of mortality and morbidity, but the reasons for differences in costs of care within and between countries are not well understood. The HealthBASKET project used a vignette methodology to compare the mean costs and prices of hospital care across providers in nine European Union countries. Data on resource use, unit costs and prices of care for female stroke patients without co-morbidity were collected from a sample of 50 hospitals. Mean costs for each provider were analysed using multiple regression. Sensitivity analysis explored the effects on cost of using official exchange rates, purchasing power parity (PPP) and proportion of national income per capita. The mean cost of a hospital episode per patient for stroke at PPP was 3813 euros (standard error 227) with an additional day in hospital typically associated with 6.9% (95% CI: 4-9%) higher costs and thrombolysis associated with 41% higher costs (10-73%). After adjusting for explanatory factors, about 76% of the variation in cost could be attributed to between-country differences, and the extent of this variation was sensitive to the method of currency conversion. There was considerable variation in the care pathways within and between countries, including differences in the availability of stroke units and access to rehabilitative services, but only the length of stay and use of thrombolytic therapy were significantly associated with higher cost. The vignette methodology appears feasible, but further research needs to consider access to healthcare over a longer follow up and to include both costs and outcomes.

Orofacial automatisms induced by acute withdrawal from high-dose midazolam mimicking nonconvulsive status epilepticus in a child

Nonconvulsive Status Epilepticus (NCSE) is not uncommon in children, and can be challenging to diagnose and treat. Etiologies vary widely and include infection, trauma and acute withdrawal from medications such as anticonvulsants. We report a child who experienced orofacial dyskinesias concerning for NCSE after withdrawal from high dose benzodiazepines andopiates. Automonic signs typically associated with sedative withdrawal were absent and treatment with benzodiazepines did not improve his symptoms. Diagnostic testing was negative, including electroencephalogram, and resolution was complete within five days. Our case demonstrates the orofacial dyskinesias that may occur during sedative medication withdrawal, and highlights potential confusion with non-convulsive status epilepticus.

Review article: the diagnosis and management of Crohn's disease in populations with high-risk rates for tuberculosis

BACKGROUND

Distinguishing Crohn's disease from intestinal tuberculosis in endemic areas is challenging as both conditions have overlapping clinical, radiological, endoscopic and histological characteristics. Furthermore, high rates of latent tuberculosis confer a considerable risk of reactivation once therapy for established Crohn's disease is started.

AIM

To review current strategies in differentiating these two conditions, and in managing Crohn's disease, in populations with high rates of tuberculosis.

METHODS

Literature review and clinical experience.

RESULTS

While various clinical, radiological, endoscopic and histological parameters may aid in differentiating Crohn's disease from intestinal tuberculosis, these remain imperfect and as treatment options differ misdiagnosis has grave consequences. We propose a diagnostic algorithm, based on currently available evidence and experience, to aid in this dilemma. We also discuss approaches to the management of Crohn's disease, including agents targeting tumour necrosis factor-alpha, in patients at risk of developing tuberculosis.

CONCLUSIONS

A diagnosis of Crohn's disease in individuals at risk for tuberculosis should only be made after careful interpretation of clinical signs, abdominal imaging and systematic endoscopic and histological assessment. Newer techniques for the diagnosis of latent tuberculosis still need to be validated in this environment, and guidelines on the treatment of latent tuberculosis in this setting require clarification.

Role of Corneal Elasticity in Damping of Intraocular Pressure

PURPOSE

To determine corneal elasticity and its contribution in damping acute intraocular pressure spikes.

METHODS

Twenty corneas with intact scleral rims were excised from human donor eyes and mounted on an artificial anterior chamber. A watertight seal was obtained with 17 corneas. Saline was infused into the chamber at a rate of 10 mL/h, and subsequent changes in pressure were measured to generate a pressure-volume relationship. Real-time anterior segment OCT was used to measure the change in radius of curvature and corneal thickness in nine eyes.

RESULTS

The pressure-versus-volume curves of all corneal-scleral buttons were concave-up asymptotes, demonstrating elasticity. The range of the slope was 0.34 to 1.6 +/- 0.29 mm Hg/microL. The mean change in the radius of curvature in the nine eyes that were visualized by optical coherence tomography (OCT) was 247 +/- 106 microm (range, 168-412 microm). The OCT image was centered on the epithelial surface. In two eyes, the entire cornea was visible by OCT throughout the course of the experiment, and corneal thickness was measured and found to decrease by 116 +/- 4 microm.

CONCLUSIONS

Human eye bank corneas demonstrate elasticity ex vivo, with expansion and thinning in response to increases in anterior chamber pressure. These elastic properties may serve as a buffering mechanism for microvolumetric changes in the eye, thus protecting the eye from intraocular pressure surges in vivo.

The course of surface deposits on a hydrophilic acrylic intraocular lens after implantation through a hexagonal cartridge

AIM

To evaluate the outcome of surface deposits that occurred during implantation of hydrophylic acrylic intraocular lenses (IOLs) through a hexagonal cartridge.

METHODS

Surface deposits were observed on the posterior surface of the ACR6D SE IOLs that were injected through a hexagonal cartridge filled with sodium hyaluronate 1%. All the patients were examined 1 day, 1 week, 1 month, 6 months and 1 year postoperatively. The location of the deposits was recorded and photographed. The patients were questioned about blurred vision, glare or halos.

RESULTS

Linear or curly deposits were detected on the posterior surface of the IOL in six patients. In four patients, the deposits were peripheral and were observed 1 week postoperatively. In two patients, the deposits were noticed immediately after implantation. In one eye, they were misinterpreted as a crack in the IOL's optic and were left in the eye. In the second patient the deposits were removed immediately after implantation with forceps. The deposits that were left after implantation (five eyes) did not resolve during 1 year of follow-up. None of the eyes developed abnormal inflammatory reaction. In three eyes the best-corrected visual acuity (BCVA) was 6/6. In the other three eyes the BCVA was 6/12. None of the patients experienced any visual disturbance.

CONCLUSIONS

Implantation of the ACR6D SE IOL through a hexagonal cartridge can lead to the formation of deposits on the posterior surface of the lens. The deposits do not resolve and may resemble a crack in the IOL. The deposits left on the IOL had no clinical relevance in our patients.

Costs and prices for inpatient care in England: Mirror twins or distant cousins?

The National Health Service (NHS) in England is introducing a national cost-per-case tariff system for the reimbursement of hospital services. Unlike most other countries with similar payment mechanisms, hospitals in England will have few alternative sources of income once the tariff system is fully implemented. This new financial regime generates powerful incentives for change, but exposes purchasers and providers to considerable financial risks. This paper examines the structure of the tariff. We describe how costs are determined, analyse the extent to which prices reflect costs, and review the results of an early evaluation of the system.

A history of pediatric critical care medicine

Critical care medicine developed out of other subspecialties' need to provide care for their most critically ill patients. Advanced technologies, the understanding of the pathophysiology of critical illness, and the development of the multidisciplinary team have made this care possible. Pediatric critical care medicine emerged in the 1960s and has expanded dramatically since then. The field has made major advances in the areas of lung injury, sepsis, traumatic brain injury, and postoperative care. We review here the evolution of modern pediatric critical care medicine from its roots in general pediatric and cardiac surgery, adult respiratory care medicine, neonatology, and pediatric anesthesiology to its current state as a unique discipline.

Small plot trials documenting effective mating disruption of oriental fruit moth by using high densities of wax-drop pheromone dispensers

In 2004 field experiments, we compared the effectiveness of various deployment densities of 0.1-ml paraffin wax drops containing 5% pheromone versus Isomate M-Rosso "rope" dispensers for disruption of Grapholita molesta (Busck). Treatments were evaluated in 0.05-ha (12-tree) plots of 'Delicious' apples receiving regular maintenance according to growers' standards, but not sprayed with insecticides. The application densities of 0.1-ml wax drops were 3 per tree (820/ha), 10 per tree (2,700/ha), 30 per tree (8,200/ha), and 100 per tree (27,300/ha). Wax drops were compared with 3-ml dispensers of pheromone-containing paraffin wax or Isomate M-Rosso ropes at 1.8 per tree (500/ha) and untreated control plots. Treatments were applied before the start of each of three moth generations. Orientational disruption, as measured by inhibition of moth captures in pheromone-baited delta traps, was greatest in plots that received 100 drops per tree (99.2%) and 30 drops per tree (99.4%). More than 55% of tethered, virgin females were mated in control plots after one night of deployment. However, no mating was recorded at the two highest application densities of wax drops where orientational disruption of traps exceeded 99%. Mating ranged from 7 to 20% among the other treatments, including Isomate rope dispensers. G. molesta males were observed closely approaching pheromone dispensers in plots containing ropes and wax drops, documenting competitive attraction between synthetic pheromone sources and feral females. The majority of observed G. molesta males approached within 60 cm of wax drops or pheromone ropes and departed within 20 s by flying upwind. Thirty wax drops per tree yielded higher mating disruption of G. molesta than did Isomate M-Rosso dispensers deployed at the recommended rate of 500/ha (1.8 per tree). Measurement of release rates confirmed behavioral data indicating that paraffin wax dispensers would need to be applied once per G. molesta generation in Michigan. Paraffin wax drops are a promising technology for moth mating disruption. They are cheaper and easier to produce, require less total pheromone per annual application, and produce better mating disruption at appropriate deployment densities compared with Isomate M-Rosso dispensers under high G. molesta population densities. The cost-effectiveness of this approach will require an appropriate mechanized applicator for wax drops.

Clinical effectiveness, tolerability and cost-effectiveness of newer drugs for epilepsy in adults: a systematic review and economic evaluation

OBJECTIVES

To examine the clinical effectiveness, tolerability and cost-effectiveness of gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), tiagabine (TGB), topiramate (TPM) and vigabatrin (VGB) for epilepsy in adults.

DATA SOURCES

Electronic databases. Internet resources. Pharmaceutical company submissions.

REVIEW METHODS

Selected studies were screened and quality assessed. Separate analyses assessed clinical effectiveness, serious, rare and long-term adverse events and cost-effectiveness. An integrated economic analysis incorporating information on costs and effects of newer and older antiepileptic drugs (AEDs) was performed to give direct comparisons of long-term costs and benefits.

RESULTS

A total of 212 studies were included in the review. All included systematic reviews were Cochrane reviews and of good quality. The quality of randomised controlled trials (RCTs) was variable. Assessment was hampered by poor reporting of methods of randomisation, allocation concealment and blinding. Few of the non-randomised studies were of good quality. The main weakness of the economic evaluations was inappropriate use of the cost-minimisation design. The included systematic reviews reported that newer AEDs were effective as adjunctive therapy compared to placebo. For newer versus older drugs, data were available for all three monotherapy AEDs, although data for OXC and TPM were limited. There was limited, poor-quality evidence of a significant improvement in cognitive function with LTG and OXC compared with older AEDs. However, there were no consistent statistically significant differences in other clinical outcomes, including proportion of seizure-free patients. No studies assessed effectiveness of AEDs in people with intellectual disabilities or in pregnant women. There was very little evidence to assess the effectiveness of AEDs in the elderly; no significant differences were found between LTG and carbamazepine monotherapy. Sixty-seven RCTs compared adjunctive therapy with placebo, older AEDs or other newer AEDs. For newer AEDs versus placebo, a trend was observed in favour of newer drugs, and there was evidence of statistically significant differences in proportion of responders favouring newer drugs. However, it was not possible to assess long-term effectiveness. Most trials were conducted in patients with partial seizures. For newer AEDs versus older drugs, there was no evidence to assess the effectiveness of LEV, LTG or OXC, and evidence for other newer drugs was limited to single studies. Trials only included patients with partial seizures and follow-up was relatively short. There was no evidence to assess effectiveness of adjunctive LEV, OXC or TPM versus other newer drugs, and there were no time to event or cognitive data. No studies assessed the effectiveness of adjunctive AEDs in the elderly or pregnant women. There was some evidence from one study (GBP versus LTG) that both drugs have some beneficial effect on behaviour in people with learning disabilities. Eighty RCTs reported the incidence of adverse events. There was no consistent or convincing evidence to draw any conclusions concerning relative safety and tolerability of newer AEDs compared with each other, older AEDs or placebo. The integrated economic analysis for monotherapy for newly diagnosed patients with partial seizures showed that older AEDs were more likely to be cost-effective, although there was considerable uncertainty in these results. The integrated analysis suggested that newer AEDs used as adjunctive therapy for refractory patients with partial seizures were more effective and more costly than continuing with existing treatment alone. Combination therapy, involving new AEDs, may be cost-effective at a threshold willingness to pay per quality-adjusted life year (QALY) greater than 20,000 pounds, depending on patients' previous treatment history. There was, again, considerable uncertainty in these results. There were few data available to determine effectiveness of treatments for patients with generalised seizures. LTG and VPA showed similar health benefits when used as monotherapy. VPA was less costly and was likely to be cost-effective. The analysis indicated that TPM might be cost-effective when used as an adjunctive therapy, with an estimated incremental cost-effectiveness ratio of 34,500 pounds compared with continuing current treatment alone.

CONCLUSIONS

There was little good-quality evidence from clinical trials to support the use of newer monotherapy or adjunctive therapy AEDs over older drugs, or to support the use of one newer AED in preference to another. In general, data relating to clinical effectiveness, safety and tolerability failed to demonstrate consistent and statistically significant differences between the drugs. The exception was comparisons between newer adjunctive AEDs and placebo, where significant differences favoured newer AEDs. However, trials often had relatively short-term treatment durations and often failed to limit recruitment to either partial or generalised onset seizures, thus limiting the applicability of the data. Newer AEDs, used as monotherapy, may be cost-effective for the treatment of patients who have experienced adverse events with older AEDs, who have failed to respond to the older drugs, or where such drugs are contraindicated. The integrated economic analysis also suggested that newer AEDs used as adjunctive therapy may be cost-effective compared with the continuing current treatment alone given a QALY of about 20,000 pounds. There is a need for more direct comparisons of the different AEDs within clinical trials, considering different treatment sequences within both monotherapy and adjunctive therapy. Length of follow-up also needs to be considered. Trials are needed that recruit patients with either partial or generalised seizures; that investigate effectiveness and cost-effectiveness in patients with generalised onset seizures and that investigate effectiveness in specific populations of epilepsy patients, as well as studies evaluating cognitive outcomes to use more stringent testing protocols and to adopt a more consistent approach in assessing outcomes. Further research is also required to assess the quality of life within trials of epilepsy therapy using preference-based measures of outcomes that generate cost-effectiveness data. Future RCTs should use CONSORT guidelines; and observational data to provide information on the use of AEDs in actual practice, including details of treatment sequences and doses.

Steel dust in the New York City subway system as a source of manganese, chromium, and iron exposures for transit workers

The United States Clean Air Act Amendments of 1990 reflected increasing concern about potential effects of low-level airborne metal exposure on a wide array of illnesses. Here we summarize results demonstrating that the New York City (NYC) subway system provides an important microenvironment for metal exposures for NYC commuters and subway workers and also describe an ongoing pilot study of NYC transit workers' exposure to steel dust. Results from the TEACH (Toxic Exposure Assessment, a Columbia and Harvard) study in 1999 of 41 high-school students strongly suggest that elevated levels of iron, manganese, and chromium in personal air samples were due to exposure to steel dust in the NYC subway. Airborne concentrations of these three metals associated with fine particulate matter were observed to be more than 100 times greater in the subway environment than in home indoor or outdoor settings in NYC. While there are currently no known health effects at the airborne levels observed in the subway system, the primary aim of the ongoing pilot study is to ascertain whether the levels of these metals in the subway air affect concentrations of these metals or related metabolites in the blood or urine of exposed transit workers, who due to their job activities could plausibly have appreciably higher exposures than typical commuters. The study design involves recruitment of 40 transit workers representing a large range in expected exposures to steel dust, the collection of personal air samples of fine particulate matter, and the collection of blood and urine samples from each monitored transit worker.

ADP-specific sensors enable universal assay of protein kinase activity

Two molecular sensors that specifically recognize ADP in a background of over 100-fold molar excess of ATP are described. These sensors are nucleic-acid based and comprise a general method for monitoring protein kinase activity. The ADP-aptamer scintillation proximity assay is configured in a single-step, homogeneous format while the allosteric ribozyme (RiboReporter) sensor generates a fluorescent signal upon ADP-dependent ribozyme self-cleavage. Both systems perform well when configured for high-throughput screening and have been used to rediscover a known protein kinase inhibitor in a high-throughput screening format.

Statins and other cholesterol-lowering medications and the presence of glaucoma

OBJECTIVE

To explore whether oral statin and other antihyperlipidemic medications are associated with open-angle glaucoma.

METHODS

The administrative clinical databases maintained at the Veterans Affairs Medical Center, Birmingham, Ala, were used to conduct a matched case-control study. Cases were all male patients aged 50 years and older with a new diagnosis of glaucoma on an outpatient or inpatient visit during the period January 1, 1997, through December 31, 2001. Ten control subjects were matched to each case according to age (within 1 year). Prescription files were assessed for statin use as well as additional medications to lower cholesterol levels. Information on comorbid medical conditions was also obtained. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Longer duration of statin use was associated with a lower risk of open-angle glaucoma (P for trend =.04) primarily among subjects with 24 months or more of use (OR, 0.60; 95% CI, 0.39-0.92). When stratified by comorbid medical condition, among those with cardiovascular disease (OR, 0.63; 95% CI, 0.42-0.97), lipid metabolism disorders (OR, 0.63; 95% CI, 0.41-0.99), and the absence of cerebrovascular disease (OR, 0.76; 95% CI, 0.58-0.99), statins demonstrated a protective effect on open-angle glaucoma. Finally, a protective association was also observed among those who used nonstatin cholesterol-lowering agents (OR, 0.59; 95% CI, 0.37-0.97).

CONCLUSIONS

Initial examination of an administrative clinical database indicates the intriguing possibility that long-term use of oral statins may be associated with a reduced risk of open-angle glaucoma, particularly among those with cardiovascular and lipid diseases. Nonstatin cholesterol-lowering agents were also associated with a reduced risk of having open-angle glaucoma. Additional investigation is warranted as to whether these classes of agents may provide an additional therapeutic addition for glaucoma.

The UK Endovascular Aneurysm Repair (EVAR) Trials: Design, Methodology and Progress

OBJECTIVES

The endovascular aneurysm repair (EVAR) trials aim to assess the efficacy of EVAR in the treatment of AAA in terms of mortality, quality of life, durability and cost-effectiveness.

DESIGN

Male and female patients aged at least 60 years with an AAA diameter measuring at least 5.5 cm on a computed tomography (CT) scan are assessed for anatomical suitability for EVAR. Suitable patients are offered entry either into EVAR Trial 1 if they are considered fit for conventional open repair or EVAR Trial 2 if they are considered unfit. EVAR 1 randomly allocates patients to EVAR or open repair and EVAR 2 randomly allocates patients to EVAR with best medical treatment or best medical treatment alone. Target recruitment for EVAR Trials 1 and 2 is 900 and 280 patients, respectively.

PROGRESS

Recruitment began in September 1999 and there are currently 40 UK centres participating in the trials. Monthly targets are being exceeded in EVAR Trial 1 with 1037 patients randomised by October 2003. EVAR Trial 2 is also meeting monthly targets with a total of 319 patients randomised. When recruitment closes in December 2003 patients will need to be followed for at least 1 year from their operation. Publication of full results for both trials is expected in mid 2005.

Elevated airborne exposures of teenagers to manganese, chromium, and iron from steel dust and New York City's subway system

There is increasing interest in potential health effects of airborne exposures to hazardous air pollutants at relatively low levels. This study focuses on sources, levels, and exposure pathways of manganese, chromium, and iron among inner-city high school students in New York City (NYC) and the contribution of subways. Samples of fine particulate matter (PM2.5) were collected during winter and summer over 48 h periods in a variety of settings including inside homes, outdoors, and personal samples (i.e., sampling packs carried by subjects). PM2.5 samples were also collected in the NYC subway system. For NYC, personal samples had significantly higher concentrations of iron, manganese, and chromium than did home indoor and ambient samples. The ratios and strong correlations between pairs of elements suggested steel dust as the source of these metals for a large subset of the personal samples. Time-activity data suggested NYC subways as a likely source of these elevated personal metals. In duplicate PM2.5 samples that integrated 8 h of underground subway exposure, iron, manganese, and chromium levels (>2 orders of magnitude above ambient levels) and their ratios were consistent with the elevated personal exposures. Steel dust in the NYC subway system was the dominant source of airborne exposures to iron, manganese, and chromium for many young people enrolled in this study, with the same results expected for other NYC subway riders who do not have occupational exposures to these metals. However, there are currently no known health effects at the exposure levels observed in this study.