Decision analysis of prophylactic mastectomy and oophorectomy in BRCA1-positive or BRCA2-positive patients.

PURPOSE: Young Ashkenazi Jewish women or those from high-risk families who test positive for BRCA1 or BRCA2 mutant genes have a significant risk of developing breast or ovarian cancer by the age of 70 years. Many question whether they should have prophylactic surgical procedures, ie, bilateral mastectomy and/or oophorectomy. METHODS: A Markov model was developed to determine the survival, quality of life, and cost-effectiveness of prophylactic surgical procedures. The probabilities of developing breast and ovarian cancer were based on literature review among women with the BRCA1 or BRCA2 gene and mortality rates were determined from Surveillance, Epidemiology, and End Results (SEER) data for 1973 to 1992. The costs for hospital and ambulatory care were estimated from Health Care Financing Administration (HCFA) payments in 1995, supplemented by managed care and fee-for-service data. Utility measures for quality-adjusted life-years (QALYs) were explicitly determined using the time-trade off method. Estimated risks for breast and ovarian cancer after prophylactic surgeries were obtained from the literature. RESULTS: For a 30-year-old woman, according to her cancer risks, prophylactic oophorectomy improved survival by 0.4 to 2.6 years; mastectomy, by 2.8 to 3.4 years; and mastectomy and oophorectomy, by 3.3 to 6.0 years over surveillance. The QALYs saved were 0.5 for oophorectomy and 1.9 for the combined procedures in the high-risk model. Prophylactic surgeries were cost-effective compared with surveillance for years of life saved, but not for QALYs. CONCLUSION: Among women who test positive for a BRCA1 or BRCA2 gene mutation, prophylactic surgery at a young age substantially improves survival, but unless genetic risk of cancer is high, provides no benefit for quality of life. Prophylactic surgery is cost-effective for years of life saved compared with other medical interventions that are deemed cost-effective.

Benefits and costs of screening Ashkenazi Jewish women for BRCA1 and BRCA2.

PURPOSE: To determine the survival benefit and cost-effectiveness of screening Ashkenazi Jewish women for three specific BRCA1/2 gene mutations. METHODS: We used a Markov model and Monte Carlo analysis to estimate the survival benefit and cost-effectiveness of screening for three specific mutations in a population in which their prevalence is 2.5% and the associated cancer risks are 56% for breast cancer and 16% for ovarian cancer. We assumed that the sensitivity and specificity of the test were 98% and 99%, respectively, that bilateral prophylactic oophorectomy would reduce ovarian cancer risk by 45%, and that bilateral prophylactic mastectomy would reduce breast cancer risk by 90%. We used Medicare payment data for treatment costs and Surveillance, Epidemiology, and End Results data for cancer survival. RESULTS: Our model suggests that genetic screening of this population could prolong average nondiscounted survival by 38 days (95% probability interval, 22 to 57 days) for combined surgery, 33 days (95% probability interval, 18 to 43 days) for mastectomy, 11 days (95% probability interval, 4 to 25 days) for oophorectomy, and 6 days (95% probability interval, 3 to 8 days) for surveillance. The respective cost-effectiveness ratios per life-year saved, with a discount rate of 3%, are $20,717, $29,970, $72,780, and $134,273. CONCLUSION: In this Ashkenazi Jewish population, with a high prevalence of BRCA1/2 mutations, genetic screening may significantly increase average survival and, depending on costs and screening/treatment strategies, may be cost-effective by the standards of accepted cancer screening tests. According to our model, screening is cost-effective only if all women who test positive undergo prophylactic surgery. These estimates require confirmation through prospective observational studies and clinical trials.

Diabetes and outcomes of coronary artery bypass graft surgery in patients with severe left ventricular dysfunction: results from The CABG Patch Trial database. The CABG Patch Trial Investigators and Coordinators.

OBJECTIVES: We examined the relationship between diabetes mellitus and outcomes after coronary artery bypass graft (CABG) surgery in patients with severe left ventricular (LV) dysfunction. BACKGROUND: Although diabetes is associated with poor outcomes after CABG surgery among unselected patients, the relationship between diabetes and mortality after CABG surgery among patients with LV dysfunction is less certain. METHODS: Using data from The CABG Patch Trial, a study of implantable cardiac defibrillator therapy, we analyzed 900 patients with ejection fraction <0.36 who underwent CABG surgery from 1990 to 1996. RESULTS: Diabetics comprised 38% of the patients, and 48% of diabetics were prescribed insulin. Diabetes was associated with hypertension, peripheral vascular disease, history of stroke, clinical heart failure and rales on physical exam. Diabetics were at higher risk for postoperative superficial sternal wound infection and renal failure. With an average follow-up time of 32 +/-16 months, actuarial all-cause mortality 48 months after CABG surgery was 26% in diabetics and 24% in nondiabetics (p = 0.66, log-rank test). Diabetes was not associated with long-term mortality in Cox multiple regression analyses. Actuarial re-hospitalization rates 48 months after CABG surgery were 85% in diabetics and 69% in nondiabetics (p = 0.0001, log-rank test). Diabetics had a 44% higher risk of re-hospitalization for any cause (p = 0.0001) and a 24% higher risk of re-admission for cardiac causes (p < 0.05). Unexpectedly, fewer arrhythmic events were found in diabetics. CONCLUSIONS: Diabetes was not a predictor of mortality after CABG surgery among patients with LV dysfunction despite associated comorbidities. However, diabetes was associated with increased postoperative complications and re-hospitalization.

The effects of apigenin-7-O-beta-D-glucuronopyranoside on reflux oesophagitis and gastritis in rats.

1. This study evaluated the inhibitory action of apigenin-7-O-beta-D-glucuronopyranoside (AGC), apigenin, and omeprazole on reflux oesophagitis and gastritis in rats. AGC was isolated from Clerodendron trichotomum leaves. 2. Oesophagitis and gastritis were induced by surgical procedure and the administration of indomethacin, respectively. The intraduodenal (i.d.) administration of AGC decreased the volume of gastric juice and increased the gastric pH compared with apigenin and omeprazole. The acid output was more inhibited by AGC in a dose-dependent manner than by apigenin and omeprazole. Compared with apigenin and omeprazole, AGC significantly decreased the size of gastric lesions, which were induced by exposure of the gastric mucosa to indomethacin. 3. Malondialdehyde (MDA) content, which is the end product of lipid peroxidation, was increased significantly after the induction of reflux oesophagitis. The MDA content was decreased by AGC (i.d. 3 mg kg(-1)), but not by either apigenin or omeprazole. This suggests that AGC has an antioxidative effect. In the oesophagitis group, the mucosal levels of glutathione (GSH) were significantly lower than that in the normal group. However, the GSH levels were preserved after administering the AGC, suggesting that AGC possesses scavenging activity. 4. In summary, AGC is more potent than apigenin and omeprazole at inhibiting reflux oesophagitis and gastritis and may therefore be a promising drug for their treatment.

Measurement of lithium transport in RBC from psychiatric patients receiving lithium carbonate and normal individuals by 7Li NMR spectroscopy.

A reproducible 7Li nuclear magnetic resonance (NMR) method, based on a modified inversion recovery (MIR) pulse sequence, was used to discriminate between intra- and extracellular lithium concentrations in red blood cell (RBC) suspensions. The rates of Na(+)-Li+ countertransport determined by the 7Li NMR method were significantly correlated with the measurements made by atomic absorption (AA) for 14 psychiatric patients receiving lithium carbonate (r = 0.937) and 14 normal individuals (r = 0.931). As expected, the rates of Na(+)-Li+ countertransport measured by MIR were significantly lower for the psychiatric patients receiving lithium carbonate than for normal individuals. The 7Li NMR method provides RBC Li+ countertransport information comparable to AA for psychiatric patients and normal individuals. A description of the advantages of the 7Li NMR method in contrast to the AA method, including the study of Li+ interactions with RBC components such as membrane proteins and anionic phospholipids, is included.

Problems with interval estimates of the incremental cost-effectiveness ratio.

The defining feature of a confidence interval is that it has a fixed minimum probability of covering the true value of the parameter being estimated, whatever the value of the parameter. The authors demonstrate by simulation that some recently proposed methods for interval estimation of the incremental cost-effectiveness ratio (ICER) either do not satisfy this definition or have other problems that limit their usefulness in applications. The problems are most prominent when the ICER is large and the true effectiveness difference is small relative to its standard error. A modification of the percentile bootstrap confidence interval that involves a reordering of the sample space provides a partial solution of the problem.

Anti-inflammatory activity of methanol extract of Kalopanax pictus bark and its fractions.

The methanol extract of Kalopanax pictus bark was evaluated on anti-inflammatory and anti-nociceptive activities in animal models. The extract produced a significant inhibition of vascular permeability at doses of 1 and 3 g/kg, p.o. in mice and of leucocyte emigration at doses of 0.15 and 0.3 g/rat, s.c., in CMC-pouch of rats. However, the extract (0.25 and 3 g/kg, p.o.) did not show anti-inflammatory activity in carrageenan induced edema of rats. The extract at a dose of 2.5 g/kg, p.o. inhibited writhing syndromes, whereas it did not exhibit anti-nociceptive in Randall-Selitto assay. The methanol extract was then partitioned with n-hexane, chloroform, ethyl acetate and butanol to give each soluble fraction and finally water soluble fraction. Among those fractions, the inhibitory effect on vascular permeability in mice was produced by ethyl acetate soluble fraction in this activity-guided fractionation. The methanol extract showed low acute toxicity in mice. These results suggest that the methanol extract of Kalopanax pictus bark has an anti-inflammatory activity which is distributed in the ethyl acetate fraction.

New flavonol glycosides from leaves of Symplocarpus renifolius.

A study was carried out to evaluate flavonol glycosides in leaves of Symplocarpus renifolius (Araceae). From the water fraction of the MeOH extract, three new flavonol glycosides were isolated along with three known compounds, kaempferol-3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-7-O-b eta-D-glucopyranoside,quercetin-3-O-beta-D-glucopyranosyl-(1-->2)-beta-D -glucopyranoside, and caffeic acid. The structures of the new flavonol glycosides were elucidated by chemical and spectral analyses as quercetin-3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-7-O-be ta-D-glucopyranoside, isorhamnetin-3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyra nos yl-7-O-beta-D-glucopyranoside, and quercetin-3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-7-O-(6 ''''-trans-caffeoyl)-beta-D-glucopyranoside.

Anti-platelet aggregation activity of stilbene derivatives from Rheum undulatum.

In continued studies on cultivated Korean rhubarb rhizomes (Rheum undulatum), three known stilbenes (desoxyrhapontigenin, rhapontigenin, piceatannol) have been screened for activity on blood platelet aggregation. Both rhapontigenin and desoxyrhapontigenin exhibited strong inhibition on the aggregation induced by arachidonic acid and collagen. However, piceatannol did not show inhibition. These inhibitory effects may partially contribute to anti-blood stagnancy activity of rhubarb.

Constituents of the herb ofIsodon excisus var.coreanus.

The studies were carried out to evaluate the constituents in the aerial part ofIsodon excisus var.coreanus (Labiatae). From the aqueous fraction of methanol extract, compound 1 (alpha-[[3-(3, 4-dihydroxyphenyl)-1-oxo-2-propenyl]oxy]-3,4-dihydroxy-benzenepropanoic acid), compound II (9-methyl-dihydroferulic acid-4-O-beta-D-glucopyranosyl (1-->2)-alpha-L- rhamnopyranosyl (1-->4)-beta-D-glucopyranoside), compound III (ent-7alpha, 11alpha, 15beta-trihydroxy-kaur-16-en-1-O-beta-D-glucopyranoside) and compound IV (2alpha, 3beta, 7alpha, 23-tetrahydroxy-olean-12-en-28-oic acid 28-O-beta-D-glucopyranoside) were isolated and identified on the basis of their physicochemical and spectroscopic evidences[IR, FAB(-)MS,(1)H-NMR,(13)C-NMR, HMQC,(1)H-(1)H COSY and HMBC (Heteronuclear Multiple Bond Connectivity)]. Especially, New compounds II and III were named isodonin A and Isodonin B respectively.

Effects of gastrodia elata bl on phencyclidine-induced schizophrenia-like psychosis in mice.

It has been demonstrated that 5-HT(1A) receptors play an important role in the pathophysiology of schizophrenia. Because Gastrodia elata Bl (GE) modulates the serotonergic system, we examined whether GE could affect phencyclidine (PCP)-induced abnormal behavior in mice. Repeated treatment with PCP increased immobility time, while it decreased social interaction time and recognition memory. PCP-induced abnormal behaviors were significantly attenuated by GE, and these effects were comparable to those of 8-OH-DPAT, a 5-HT(1A) receptor agonist. Furthermore, GE-mediated effects were counteracted by WAY 100635, a 5-HT(1A) receptor antagonist. Our results suggest that the antipsychotic effects of GE are, at least in part, mediated via activation of 5-HT(1A) in mice.

Cost-effectiveness analysis and policy choices: investing in health systems.

The role of health systems infrastructure in studies of cost-effectiveness analysis and health resource allocation is discussed, and previous health sector cost-effectiveness analyses are cited. Two substantial difficulties concerning the nature of health system costs and the policy choices are presented. First, the issue of health system infrastructure can be addressed by use of computer models such as the Health Resource Allocation Model (HRAM) developed at Harvard, which integrates cost-effectiveness and burden of disease data. It was found that a model which allows for expansion in health infrastructure yields nearly 40% more total DALYs for a hypothetical sub-Saharan African country than a model which neglects infrastructure expansion. Widespread use of cost-effectiveness databases for resource allocations in the health sector will require the cost-effectiveness analyses shift from reporting costs to reporting production functions. Second, three distinct policy questions can be treated using these tools, each necessitating its own inputs and constraints: allocations when given a fixed budget and health infrastructure, or when given resources for marginal expansion, or when given a politically constrained situation of expanding resources. Confusion concerning which question is being addressed must be avoided through development of a consistent and rigorous approach to using cost-effectiveness data for informing resource allocations.

PIP: A proposed method is presented by which the cost-effectiveness of investing in the physical and human infrastructure of the health system can be evaluated. The role of health systems infrastructure in studies of cost-effectiveness analysis and health resource allocation is discussed, and previous health sector cost-effectiveness analyses are cited. Two substantial difficulties concerning the nature of health system costs and the policy choices are presented. First, the issue of health system infrastructure can be addressed by use of computer models such as the Health Resource Allocation Model (HRAM) developed at Harvard in the General Algebraic Modeling System (GAMS), which integrates cost-effectiveness and burden of disease data. It was found that a model which allows for expansion in health infrastructure yields nearly 40% more total disability-adjusted life years (DALYs) for a hypothetical Sub-Saharan African country with a population of 10 million and GDP per capita of $340, than a model which neglects infrastructure expansion. The most important interventions by expenditure are screening and treatment of acute respiratory infections, malaria, tuberculosis, measles as well as promotion of oral rehydration therapy, breast-feeding, tetanus, and hygiene. Widespread use of cost-effectiveness databases for resource allocations in the health sector will require that cost-effectiveness analyses shift from reporting costs to reporting production functions. Distinct policy questions can be addressed with cost-effectiveness analysis, each necessitating its own inputs and constraints: 1) allocations when given a fixed budget and health infrastructure, or 2) when given resources for marginal expansion, or 3) when given a politically constrained situation of expanding resources. The development of a consistent approach to using cost-effectiveness data for informing resource allocations precludes confusion concerning which question must be addressed. Finally, some implications for future cost-effectiveness studies are highlighted.

Bayesian estimation of cost-effectiveness ratios from clinical trials.

Estimation of the incremental cost-effectiveness ratio (ICER) is difficult for several reasons: treatments that decrease both cost and effectiveness and treatments that increase both cost and effectiveness can yield identical values of the ICER; the ICER is a discontinuous function of the mean difference in effectiveness; and the standard estimate of the ICER is a ratio. To address these difficulties, we have developed a Bayesian methodology that involves computing posterior probabilities for the four quadrants and separate interval estimates of ICER for the quadrants of interest. We compute these quantities by simulating draws from the posterior distribution of the cost and effectiveness parameters and tabulating the appropriate posterior probabilities and quantiles. We demonstrate the method by re-analysing three previously published clinical trials.

New flavonoids from the aerial parts of Aconitum chiisanense.

The studies were carried out to evaluate the constituents in the aerial part of Aconitum chiisanense (Ranunculaceae). From the butanol fraction of the methanol extract, kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (I), quercetin 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (II), kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-feruloyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (III), kaempferol 3- O-beta-glucopyranoside-7- O-(6-benzoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (IV), kaempferol 7- O-(6-trans)-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (V), and kaempferol 7- O-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (VI) were isolated and identified on the basis of their physicochemical and spectroscopic evidence (UV, IR, FAB(-)MS, (1)H-NMR, (13)C-NMR, (1)H- (1)H COSY, HMQC and HMBC). New compounds I-VI were named chiisanin (I), chiiribanin (II), chiiribaconin (III), chiirin (IV), chiiricanin (V), and chiirirhamnin (VI), respectively.

Screening of Korean herbal medicines used to improve cognitive function for anti-cholinesterase activity.

Methanolic extracts of seven herbs (Acorus calamus, Acorus gramineus, Bupleurm facaltum, Dioscorea batatas, Epimedium koreanum, Poria cocos and Zizyphi jujuba) used in traditional Korean medicine for improvement of memory and cognition in old age were tested for cholinesterase inhibitory properties using the Ellman colorimetric method. Significant inhibition of the enzyme at 200 microg/ml was observed for extracts from A. calamus and E. koreanum. The possible bases for the reputation of these and the other herbs tested are discussed in the light of previous investigations into their chemistry and biological activity.

Probabilistic sensitivity analysis in cost-effectiveness. An application from a study of vaccination against pneumococcal bacteremia in the elderly.

OBJECTIVES: We explore the policy implications of probabilistic sensitivity analysis in cost-effectiveness analysis by applying simulation methods to a decision model. METHODS: We present the multiway sensitivity analysis results of a study of the cost-effectiveness of vaccination against pneumococcal bacteremia in the elderly. We then execute a probabilistic sensitivity analysis of the cost-effectiveness ratio by specifying posterior distributions for the uncertain parameters in our decision analysis model. In order to estimate probability intervals, we rank the numerical values of the simulated incremental cost-effectiveness ratios (ICERs) to take into account preferences along the cost-effectiveness plane. RESULTS: The 95% probability intervals for the ICER were generally much narrower than the difference between the best case and worst case results from a multiway sensitivity analysis. Although the multiway sensitivity analysis had indicated that, in the worst case, vaccination in the 85 and older age group was not acceptable from a policy standpoint, probabilistic methods indicated that the cost-effectiveness of vaccination was below $50,000 per quality-adjusted life-year in greater than 92% of the simulations and below $100,000 in greater than 95% of the simulations. CONCLUSIONS: Probabilistic methods can supplement multiway sensitivity analyses to provide a more comprehensive picture of the uncertainty associated with cost-effectiveness ratios and thereby inform policy decisions.

Phenanthrenequinone-doped poly(methyl methacrylate) photopolymer bulk for volume holographic data storage.

We present the design and fabrication of a phenanthrenequinone-doped poly(methyl methacrylate) photopolymer material. Large blocks of samples were made, and the material showed negligible shrinkage after optical exposures. We recorded and reconstructed 250 holograms at a single spot, using a 1-cm(3) block.

Risk stratification for coronary bypass surgery in patients with left ventricular dysfunction: analysis of the coronary artery bypass grafting patch trial database.

BACKGROUND: Preoperative characteristics may influence morbidity and mortality in patients undergoing coronary artery bypass grafting (CABG). The CABG Patch Trial was designed to assess the impact of prophylactic insertion of an implantable cardioverter-defibrillator in patients undergoing high-risk CABG. This database was used to investigate the influence of symptomatic congestive heart failure (CHF) and angina on morbidity and mortality in CABG patients with ventricular dysfunction. METHODS AND RESULTS: Data were analyzed for 900 randomized patients with an ejection fraction

Decision analysis of tamoxifen for the prevention of invasive breast cancer.

PURPOSE: The recent Breast Cancer Prevention Trial has shown that tamoxifen may prevent invasive breast cancer. We used a Markov model to estimate the long-term effects of chemoprevention with tamoxifen on survival, quality-adjusted survival, and health care costs. METHODS: We used a hypothetical cohort of women with breast-cancer risk similar to that of participants in the Breast Cancer Prevention Trial, and a computer-based decision analysis (Markov model and 500 Monte Carlo simulations) to model the outcomes of interest. Survival calculations were from Surveillance, Epidemiology, and End-Results (SEER) data; preference ratings from a time trade-off questionnaire administered to a group of average-risk women; and cost estimates from the Group Health Cooperative of Puget Sound and the Health Care Financing Administration. We obtained utility measures for quality-adjustment by administering a time trade-off questionnaire to a group of community-based women. RESULTS: Use of tamoxifen prolonged the average survival of cohort members by 69 days (95% probability interval [PI] 27 to 117) for those who started use at age 35 years; 40 days (95% PI 16 to 67) for those who started use at age 50 years; and 27 days (95% PI 14 to 40) for those who started use at age 60 years. Tamoxifen extended quality-adjusted survival by 38 days (95% PI 0.1 to 82) at age 35, 25 days (95% PI 0 to 50) at age 50, and 22 days (95% PI 5 to 39) days at age 60. Chemoprevention with tamoxifen cost $46,619 (95% PI $27,928 to $98,796) per life year life saved for women who started at age 35; for women over age 50, it cost more than $50,000 per life year saved. DISCUSSION: Tamoxifen use may improve long-term survival and quality-adjusted survival among women who are at increased risk of breast cancer, but this benefit diminishes with age. Tamoxifen is cost-effective in comparison with other cancer treatment strategies for younger women only.

Prevention with tamoxifen or other hormones versus prophylactic surgery in BRCA1/2-positive women: a decision analysis.

PURPOSE: Recent randomized controlled trials have shown that tamoxifen and raloxifene may prevent invasive breast cancer. This decision analysis study compares the outcomes of chemoprevention with tamoxifen, raloxifene, or oral contraceptives with the outcomes of prophylactic surgery among women with high-risk BRCA1/2 mutations. PATIENTS AND METHODS: We used a simulated cohort of 30-year-old women who tested positive for BRCA1/2 mutations and constructed a Markov model with Monte Carlo simulations, incorporating cumulative breast and ovarian cancer incidence rates from the literature and survival figures from SEER data. We assumed that prophylactic surgery reduces ovarian cancer risk by 45% and breast cancer risk by 90%, that tamoxifen reduces invasive breast cancer risk by 49%, and that raloxifene has similar efficacy and safety in premenopausal and postmenopausal women. We used data obtained from high-risk women by a time trade-off questionnaire to calculate quality-adjusted life-years. We based our cost estimates for hospital and ambulatory care on Health Care Financing Administration payments, the SEER-HCFA database, and the Pharmacy Fundamental Reference. RESULTS: In our model, a 30-year-old BRCA1/2+ woman could prolong survival by 0.9 years (95% probability interval, 0.4-1.2 years) by having bilateral oophorectomy, 3.4 years (2.7-3.7 years) by having bilateral mastectomy, and 4.3 years (3.6-4.6 years) by having both procedures instead of surveillance alone. Chemoprevention with tamoxifen and raloxifene increased survival by 1.6 years (1.0-2.1 years) and 2.2 years (1.3-2.8 years), respectively. Chemoprevention yielded more quality-adjusted life-years than did prophylactic surgery, even when treatment was delayed to age 40 or 50 years. All these procedures were cost-effective or cost-saving compared with surveillance alone. DISCUSSION: Our model suggests that although surgery may yield more substantial survival and cost benefits, quality of life issues may make chemoprevention a more attractive option for young women at high genetic risk.