Disability-Adjusted Life Years Averted Versus Quality-Adjusted Life Years Gained: A Model Analysis for Breast Cancer Screening

ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold.     

用气相色谱-同位素比值质谱法测定体外肠道细菌发酵产生的短链脂肪酸

目的：了解肠道细菌发酵产生短链脂肪酸的情况，为乳糖不耐症状的发生提供依据。方法：在体外进行细菌培养，用稳定性同位素标记的葡萄糖作底物，用气相色谱－同位素比值质谱法测定短链脂肪酸。结果：细菌纯培养显示不同菌株产生的短链脂肪酸不同。人体粪便培养表明不同人体产生的短链脂肪酸的种类相同，而各种类数量不同。结论：所测定的人体肠道发酵产生短链脂肪酸的能力不同，可能与乳糖不耐症状的发生有关。     

Exposure to infant siblings during early life and risk of multiple sclerosis

Context  The "hygiene hypothesis" has implicated sibship as a marker of infection load during early life and suggests that exposure or reexposure to infections can influence the developing immune system. Viral infection has also been implicated in the pathogenesis of multiple sclerosis (MS). Objectives  To evaluate whether exposure to infant siblings in early life is associated with the risk of MS, and to explore the possible mechanism for any apparent protective effect, including altered Epstein-Barr virus (EBV) infection patterns. Design, Setting, and Patients  Population-based case-control study in Tasmania, Australia, from 1999 to 2001 based on 136 cases of magnetic resonance imaging–confirmed MS and 272 community controls, matched on sex and year of birth. Main Outcome Measure  Risk of MS by duration of contact with younger siblings aged less than 2 years in the first 6 years of life. Results  Increasing duration of contact with a younger sibling aged less than 2 years in the first 6 years of life was associated with reduced MS risk (adjusted odds ratios [AORs]: <1 infant-year, 1.00 [reference]; 1 to <3 infant-years, 0.57 [95% confidence interval {CI}, 0.33-0.98]; 3 to <5 infant-years, 0.40 [95% CI, 0.19-0.92]; 5 infant-years, 0.12 [95% CI, 0.02-0.88]; test for trend, P = .002). A history of exposure to infant siblings was associated with a reduced IgG response to EBV among controls. Controls with at least 1 infant-year contact had a reduced risk of infectious mononucleosis and a reduced risk of very high composite EBV IgG titers (AOR, 0.33; 95% CI, 0.11-0.98) compared with other controls. The inverse association between higher infant contact and MS was independent of EBV IgG titer. Conclusion  Higher infant sibling exposure in the first 6 years of life was associated with a reduced risk of MS, possibly by altering childhood infection patterns and related immune responses.      

The influence of atropine and atenolol on the cardiac haemodynamic effects of NG-nitro-L-arginine methyl ester in conscious, Long Evans rats.

1. In the present study, the extent to which baroreflexes contribute to the cardiac effects of NG-nitro-L-arginine methyl ester (L-NAME) was assessed in conscious, Long Evans rats chronically instrumented with thoracic electromagnetic flow probes for the measurement of cardiac haemodynamics. 2. L-NAME (10 mg kg-1, i.v.) was administered in the absence (n = 6) and in the presence (n = 7) of atropine (1 mg kg-1) and atenolol (1 mg kg-1). 3. L-NAME caused a marked increase in mean arterial pressure and marked reductions in total peripheral conductance, cardiac output, heart rate, stroke volume, peak thoracic flow and the maximum rate of rise of aortic flow. 4. Administration of atropine, after the maximal bradycardic effect of L-NAME was established, restored the heart rate to resting levels. Concurrently, there was a reduction in stroke volume, such that cardiac output, although transiently elevated, did not show a sustained increase. No other variables were significantly affected by atropine. Additional administration of atenolol had no effect other than to cause a slight bradycardia, such that in the presence of atropine and atenolol, heart rate was not different from that in animals receiving atropine and atenolol before L-NAME. 5. In the presence of atropine and atenolol, L-NAME had similar pressor, vasoconstrictor and cardiac haemodynamic effects to those in untreated animals, although the bradycardia was significantly attenuated. However, there was still a significant reduction in heart rate following L-NAME in the presence of atropine and atenolol.(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of a new blood glucose strip: comparison of Visidex, Visidex II, and Chemstrip bG with Glucose Analyzer determination of blood glucose

Chemical test strips for estimating blood glucose are reliable, rapid, and convenient when properly used. Ames (Miles Laboratories, Elkhart, Indiana) has recently introduced a new product, Visidex II, which does not require water for development. This study compares the Visidex II with its predecessor Visidex, an established test strip, the Bio-Dynamics Chemstrip bG (Boehringer-Mannheim, Indianapolis, Indiana), and plasma glucose as measured by standard laboratory methods. Determination of blood glucose by visual inspection by all chemical test strips gave an estimation of true plasma glucose, and was reliable in predicting those values that were hypo- and hyperglycemic, although Chemstrip bG tended to underestimate in the hypo- and euglycemic ranges. Visidex II is more convenient to use than Visidex and is equally reliable in estimating true plasma glucose. In addition, strips from 20 patient samples were read daily for 7 days. Reacted Chemstrip bG test strips began to deteriorate within 24 h, and showed a 27% decline in estimations by day 3. Reacted Visidex II strips were stable for 1 day, but then rapidly declined to 50% of the original estimation by day 4.     

Chronic stable ischaemia protects against myocyte damage during beating heart coronary surgery.

OBJECTIVES: Many patients with coronary artery disease demonstrate chronic resting ischaemic myocardial dysfunction. We have investigated whether this ischaemia influences the myocardial damage caused by the period of coronary occlusion involved in beating heart surgery. METHODS: Thirty-three patients with chronic stable angina and normal left ventricular ejection fraction were studied. To make our model clinically appropriate, we included patients with a wide range of ischaemic times, ages and in a subset of 10 patients a surgical preconditioning protocol. Myocyte injury was assessed from venous Troponin T release measured on days 1, 2, and 3. We used intraoperative transoesophageal M mode echocardiograms and simultaneous high-fidelity left ventricular pressure to assess whether patients were demonstrating the functional effects of ischaemia (asynchronous regional contraction with reduced mechanical function). RESULTS: Patients demonstrated the functional effects of resting ischaemia and 17 did not. Patients with resting ischaemia had lower preoperative values of regional peak power and work and all three variables increased significantly with surgery. Venous Troponin T levels at 48 and 72 h postoperatively were lower in those with preoperative resting ischaemia (median (interquartile range) 0.13 (0.08-0.20) vs 0.21 (0.13-0.69) for 48 h and 0.10 (0.08-0.19) vs 0.26 (0.12-0.51) for 72 h). Stepwise multiple linear regression of total postoperative troponin release (measured as the area under the curve of troponin release) demonstrated two independent determinants (R squared for model 0.40): longer ischaemic time, and increasing values of cycle efficiency. The surgical ischaemic preconditioning protocol and preoperative collaterals were not independent determinants. CONCLUSIONS: In patients with chronic coronary artery disease, stable preoperative ischaemia may thus represent a naturally occurring form of myocardial protection, whose presence reduces Troponin T release after beating heart surgery. This protection is different in nature from classical ischaemic preconditioning.     

Quality assessment of transfusion practice in elective surgery

A program of quality assurance (QA) was adopted to improve blood transfusion practice in elective surgery at a large urban hospital. For this purpose, a cooperative multidisciplinary group was formed, key indicators were identified, and an organization was set up. Data collected by this organization in the 1-year period needed for implementation of the program indicated that blood misuse was common practice. In fact, overrequest, overtransfusion, excessive reconstitution of whole blood (i.e., concurrent transfusion of red cells and fresh-frozen plasma), and underuse of predeposit were found in all ten surgical departments of the hospital. In a pilot study, data were collected from one surgical department during and after the implementation phase of the QA program; comparison of these data showed a postimplementation reduction of about two thirds in overtransfusion, whereas overrequest, reconstitution of whole blood, and predeposit rates remained unchanged. These results prompted continuation of the program in order to reach a definitive evaluation of its effectiveness.     

Migraine preventive medications: a reappraisal

Newer acute care migraine medications demonstrate improved rapidity of action, consistent effectiveness, excellent safety profiles, and rarely cause rebound headaches. Their use could decrease the need for migraine-preventive medication. The present analysis derives a formula that can be used by practitioners to determine the cost-effectiveness of various migraine-preventive medications relative to selected acute-care medications. We propose a measure called the cost-equivalent number (CEN), the number of headaches per month at which the cost of the preventive medication equals the cost savings in acute-care treatment realized by using the preventive medication. The use of the CEN individualizes the decision of whether to use a migraine-preventive medication, weighing both the efficacy and cost of the preventive medication against the cost of the acute-care medication. A CEN lower than the migraine frequency suggests that use of a preventive medication will be cost-effective.     

Bowel-associated dermatosis-arthritis syndrome

A 48-year-old woman, who had undergone reversal of a jejunal loop, presented with skin eruptions, myalgia and arthralgia. Delayed gastric emptying was associated with a gastric phytobezoar. The clinicopathological features and response to therapy were typical of the dermatosis-arthritis syndrome, and probably were related to bacterial overgrowth.