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Medical therapy versus coronary angioplasty in stable coronary artery disease: a critical review of the literature.

The recent publication of the Atorvastatin Versus Revascularization Treatment (AVERT) trial has renewed debate on the optimal management strategy for relatively stable patients with coronary artery disease. Currently, coronary angiography and percutaneous coronary intervention are often performed in stable patients with good exercise tolerance who have not been treated with proven medications such as aspirin, statins and beta-adrenergic blocking agents in conjunction with comprehensive lifestyle modification. We review the results of prior trials comparing medical therapy with angioplasty and assess their strengths and limitations and then make conclusions about the aggregate data. Next, we describe the ongoing Clinical Outcome Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial, which will be the largest of the studies comparing optimal medical therapy and percutaneous revascularization. This study will employ intensive medical management in all patients with coronary disease, and the incremental benefit of state of the art revascularization techniques in terms of clinical event reduction, quality of life issues and cost-effectiveness will be addressed. For now, aggressive medical therapy and revascularization should be viewed as complementary rather than opposing strategies. All patients with coronary heart disease should receive proven medical and lifestyle prescriptions to favorably alter the atherosclerotic process. Percutaneous revascularization without comprehensive risk factor modification is a suboptimal therapeutic strategy.

Angioplasty, Balloon, Coronary↗

Putting drug use in context. Life-lines of African American women who smoke crack.

The purpose of this exploratory study was to describe a group of African American women who smoke crack. Using aggregate data from 208 interviews with women crack smokers, we randomly selected 25 women's interview data to create the 25 life-lines. These life-lines were developed in a similar manner to the time-line analysis described by Fullilove and her colleagues (1992); we focused on events that are either extraordinarily disturbing (e.g., rape, incest, death of a child, etc.), events that are usual but often stressful (e.g., birth of a child, death of a parent, etc.), and on periods of drug use. We chose this method of analysis so as to highlight the context in which many women come to use crack cocaine. The life-lines provided a retrospective (but time-ordered) perspective and in several ways provided preliminary support for a stress-diathesis perspective.

Adult↗

Evaluating surgically induced astigmatism.

Using a modification of vector analysis for calculating surgically induced astigmatism, we describe a simple method that divides the induced cylinder into two orthogonal components. This decomposition allows with-the-rule and against-the-rule astigmatic changes to be calculated for individual case analysis, as well as for statistical analysis of aggregate data. Because it is based on the true induced cylinder, as determined by optical principles, this method overcomes some of the problems associated with earlier methods of evaluating surgically induced astigmatism.

Astigmatism↗

The accreditation status of student health services at academic medical centers.

BACKGROUND: Student health services (SHSs) on campuses with academic medical centers (AMCs; schools affiliated with teaching hospitals) often provide clinical services (including occupational health services) for students and staff. There are few aggregate data about the accreditation status of these health services. METHOD: A cross-sectional survey of SHSs at the 124 medical schools in the United States was conducted in spring 1999. SHSs were questioned about their accreditation status. RESULTS: One-hundred three SHSs were included in the survey. Forty-seven (46%) of the SHSs were accredited, 30 (64%) through the Joint Commission on Accreditation of Healthcare Organizations, and the remainder through the Accreditation Association of Ambulatory Health Care (AAAHC). The Joint Commission predominated among private SHSs (13/15 [87%]), but public institutions were more evenly divided. Most of the SHSs accredited as freestanding ambulatory care centers were AAAHC accredited (16/27 [59%]). Nearly all the SHSs accredited as satellites of the AMCs were Joint Commission accredited. CONCLUSION: Although fewer than one-half of SHSs at AMCs are accredited either through the Joint Commission or AAAHC, this is a far higher percentage than of accredited SHSs in general (134/1,500 [9%]). The Joint Commission dominates as the accrediting body for SHSs at AMCs largely because of the high-proportion of services accredited as satellites of the AMCs. Although the accreditation process is costly and time-consuming and may appear daunting, SHSs at AMCs should pursue accreditation to ensure quality in health care processes.

Academic Medical Centers↗

Asthma deaths in Washington State, 1980-1989: geographic and demographic distributions.

BACKGROUND: Asthma prevalence and mortality rates have been increasing for the past two decades for reasons that are not definitively known. Few studies of asthma mortality rates have concentrated on subnational regions, such as individual states. OBJECTIVE: To determine geographic and demographic patterns of asthma mortality in Washington State during 1980 through 1989 and to compare aggregated data with patterns of chronic bronchitis mortality. METHODS: Age-adjusted mortality rates for asthma and chronic bronchitis were calculated from 1980 through 1989 for all age groups. Rates were then disaggregated by county, gender, age, and race. Rates were calculated from death certificates listed by the Washington State Center for Health Statistics as either asthma (ICD9-493) or chronic bronchitis (ICD9-490 and 491) and census data. RESULTS: During the period 1980-1989, age-adjusted mortality rates for asthma increased by 15% while those for bronchitis decreased by 43%. There was no consistent geographic pattern in the increase, though one county with a very small population had the highest rate of increase. Female asthma mortality rates increased during the decade, while male asthma mortality rates and both male and female bronchitis rates decreased. Two populations demonstrated pronounced increases in asthma mortality rates: females between ages 40 and 69 years and non-whites. CONCLUSIONS: While increased asthma mortality rates have been noted elsewhere for non-whites, this is the first study to demonstrate elevated mortality rates for middle aged women. The explanation for this remains a mystery.

Adolescent↗

Trends and ethnic differences in asthma hospitalization rates in Singapore, 1991 to 1998.

BACKGROUND: A few reports have indicated that asthma hospitalization rates in several countries have stopped rising or started falling in the 1990s. AIM: To describe recent trends and ethnic differences in asthma hospitalization rates in Singapore from 1991 to 1998. METHODS: Asthma hospitalization rates in all hospitals were analyzed by age groups, sex, ethnicity, and individual years, using aggregated data for asthma (ICD-9 493 and ICD-10 J45, J46) from 1991 to 1998, when nationwide data from the Central Claims Processing System were available. RESULTS: Between 1991 and 1998 there were a total of 37,615 hospital admissions for asthma, giving an annual average rate of 17.1 hospital admissions per 10,000 persons. Overall, the rates of asthma hospitalization fell by 28% from 21.7 per 10,000 in 1991 to 15.4 per 10,000 in 1998 (3.5% annually). The trends were broadly based across all age, sex, and ethnic groups. Hospitalizations were more common in boys than in girls aged 0 to 4 (male/female ratio 1.69), but less common in men than women aged 35 to 64 (male/female ratio 0.81). Rates of asthma hospital admissions were higher in Malays (32.8 per 10,000) and Indians (40.8 per 10,000) than Chinese (11.9 per 10,000). CONCLUSIONS: In line with findings from several countries, there have been recent declines in rates of hospital admissions for asthma in Singapore in the 1990s. The declines were broadly based across all population subgroups and parallel previously observed declines in mortality in adults. However, considerable ethnic differences in levels of asthma hospitalization still exist.

Adolescent↗

Human herpesvirus 8 and Kaposi's sarcoma.

In the last 2 years, the discovery that the suspected causative agent of Kaposi's sarcoma (KS) is a new gamma-herpesvirus, called human herpesvirus type 8 (HHV8) or Kaposi's sarcoma-associated herpesvirus (KSHV), has been followed by studies showing it to be a sine qua non of all clinical forms of KS and a specific marker for KS in the differential diagnosis of angioproliferative lesions. Reports that the virus is ubiquitous have been based on the polymerase chain reaction and appear to be contradicted by serological studies of blood donors and patients with acquired immunodeficiency syndrome (AIDS)-related and classical KS. Further serological surveys and the application of molecular probes in histological sections should resolve the issue. The recent descriptions of KSHV RNA molecules and several viral mimickers of human cytokines offer the chance to map the viral latent-lytic cycle and will change the direction of cytokine research in KS. These discoveries suggest that the increase of endemic classical KS noted in Nordic countries before the AIDS epidemic was due to spread of KSHV by unknown routes. The aggregate data should force a paradigm shift away from the notion that human immunodeficiency virus infection has a necessary role to play in AIDS-KS other than as a cause of progressive immunodeficiency.

Diagnosis, Differential↗

Integrating GIS components with knowledge discovery technology for environmental health decision support.

This paper presents a new category of decision-support tools that builds on today's Geographic Information Systems (GIS) and On-Line Analytical Processing (OLAP) technologies to facilitate Geographic Knowledge Discovery (GKD). This new category, named Spatial OLAP (SOLAP), has been an R&D topic for about 5 years in a few university labs and is now being implemented by early adopters in different fields, including public health where it provides numerous advantages. In this paper, we present an example of a SOLAP application in the field of environmental health: the ICEM-SE project. After having presented this example, we describe the design of this system and explain how it provides fast and easy access to the detailed and aggregated data that are needed for GKD and decision-making in public health. The SOLAP concept is also described and a comparison is made with traditional GIS applications.

Artificial Intelligence↗

The effect of new drug approvals on HIV mortality in the US, 1987-1998.

After increasing steadily from 1987 to 1995, the number of US deaths caused by human immunodeficiency virus (HIV) declined sharply from 1995 to 1998. We analyse aggregate data to consider the hypothesis that this decline was due to a rapid increase in the number of drugs available to treat HIV. The evidence suggests that new drugs played a key role in the post-1995 decline in HIV mortality. The annual number of HIV deaths is estimated to have been reduced by over 6000, on average, by an additional HIV drug approval. The social return to HIV drug innovation appears to be extremely large.

Anti-HIV Agents↗

Australian trends in mortality by socioeconomic status using NSW small area data, 1970-89.

This ecological study examines trends in socioeconomic differentials in mortality in New South Wales, Australia, over a 20-year period (1970-89). The proportion unskilled was used as the indicator of socioeconomic status and its selection justified. Using census data aggregated by Local Government Area, the relationship between mortality and socioeconomic status was examined using quintiles based on the proportion unskilled in the population. Local Government Areas were also sorted into quintiles using mortality rates (0-74 years) to describe change in mortality differentials over time. Socioeconomic differentials were more evident in the relatively homogeneous Local Government Areas within the Sydney Statistical Division than in the remaining NSW Statistical Divisions which are more heterogeneous and predominantly rural. Although there has been an overall decline in mortality for males and females, and for high and low status groups, over this period the relative socioeconomic differentials have not declined. For the most recent period (1985-89) there appears to be some widening of differentials for males. The NSW state trends are generally similar to those reported for Britain and for other industrialised countries, suggesting that this is a common trend and that policies to reduce inequalities have not been effective.

Adolescent↗

The predictive utility of expressed emotion in schizophrenia: an aggregate analysis.

We analysed aggregate data from 25 studies linking Expressed Emotion (EE) and schizophrenia. We had access to original data sets from 17 studies, and used published data from the remainder. This provided us with 1346 cases from around the world. The association of EE with relapse was overwhelming, and was maintained whatever the geographical location. The predictive capacity of EE was virtually identical in men and women. While high contact with a high EE relative increased the risk of relapse, the opposite was true in low EE households. Medication and EE were independently related to relapse, and thus EE status has no bearing on the decision to prescribe. Our findings were confirmed using log-linear analysis.

Cross-Cultural Comparison↗

Binding of polyaminocarboxylate chelators to the active-site copper inhibits the GSNO-reductase activity but not the superoxide dismutase activity of Cu,Zn-superoxide dismutase.

In addition to its superoxide dismutase (SOD) activity, Cu,Zn-superoxide dismutase (CuZnSOD) catalyzes the reductive decomposition of S-nitroso-L-glutathione (GSNO) in the presence of thiols such as L-glutathione (GSH). The GSNO-reductase activity but not the superoxide dismutase (SOD) activity of CuZnSOD is inhibited by the commonly used polyaminocarboxylate metal ion chelators, EDTA and DTPA. The basis for this selective inhibition is systematically investigated here. Incubation with EDTA or DTPA caused a time-dependent decrease in the 680 nm d-d absorption of Cu(II)ZnSOD but no loss in SOD activity or in the level of metal loading of the enzyme as determined by ICP-MS. The chelators also protected the SOD activity against inhibition by the arginine-specific reagent, phenylglyoxal. Measurements of both the time course of SNO absorption decay at 333 nm and oxymyoglobin scavenging of the NO that is released confirmed that the chelators inhibit CuZnSOD catalysis of GSNO reductive decomposition by GSH. The decreased GSNO-reductase activity is correlated with decreased rates of Cu(II)ZnSOD reduction by GSH in the presence of the chelators as monitored spectrophotometrically at 680 nm. The aggregate data suggest binding of the chelators to CuZnSOD, which was detected by isothermal titration calorimetry (ITC). Dissociation constants of 0.08 +/- 0.02 and 8.3 +/- 0.2 microM were calculated from the ITC thermograms for the binding of a single EDTA and DTPA, respectively, to the CuZnSOD homodimer. No association was detected under the same conditions with the metal-free enzyme (EESOD). Thus, EDTA and DTPA must bind to the solvent-exposed active-site copper of one subunit without removing the metal. This induces a conformational change at the second active site that inhibits the GSNO-reductase but not the SOD activity of the enzyme.

Animals↗

Mechanistic investigations of 1-aminocyclopropane 1-carboxylic acid oxidase with alternate cyclic and acyclic substrates.

The behavior of three cyclic and three acyclic analogues of 1-aminocyclopropane-1-carboxylic acid (ACC) with ACC oxidase has been analyzed with regard to turnover rates, product distribution, and O(2) uncoupling. The cyclic analogues all form ethylene, and the acyclic analogues all undergo decarboxylation. The degree of uncoupling varies from almost none (ACC) to 21-fold (glycine), while turnover rates (k(cat)) are all within a factor of 4-fold of that of ACC. The aggregate data point toward a rate-determining formation of an activated iron-oxo intermediate, which partitions between amine oxidation and reductive uncoupling in a manner that is dependent on substrate structure.

Acids, Acyclic↗

Retrospective temporal and spatial mobility of adult Iowa women.

Human exposure assessments require a linkage between toxicant concentrations in occupied spaces and the receptor's mobility pattern. Databases reporting distinct populations' mobility in various parts of the home, time outside the home, and time in another building are scarce. Temporal longitudinal trends in these mobility patterns for specific age and gender groups are nonexistent. This paper describes subgroup trends in the spatial and temporal mobility patterns within the home, outside the home, and in another building for 619 Iowa females that occupied the same home for at least 20 years. The study found that the mean time spent at home for the participants ranged from a low of 69.4% for the 50-59 year age group to a high of 81.6% for the over 80-year-old age group. Participants who lived in either one- or two- story homes with basements spent the majority of their residential occupancy on the first story. Trends across age varied for other subgroups by number of children, education, and urban/rural status. Since all of these trends were nonlinear, they indicate that error exists when assuming a constant, such as a 75% home occupancy factor, which has been advocated by some researchers and agencies. In addition, while aggregate data, such as presented in this report, are more helpful in deriving risk estimates for population subgroups, they cannot supplant good individual-level data for determining risks.

Adult↗

[Failure prevention in clinical practice through identification of failure examples].

"Learning from ones mistakes" is an essential part of clinical quality improvement. But focusing on a retrospective analysis of mishaps from the past is not sufficient for quality enhancements, nor is the restriction to mistakes in the solely legal sense. Analysis has to include anonymous data aggregated over dissatisfying results from multiple sources. Recognizing patterns of underlying causes for errors is the key to effective error prevention. In many cases the true cause might be predominantly organizational.

Mandatory Reporting↗

Relationship of cytokeratin 20 and CD44 protein expression with WHO/ISUP grade in pTa and pT1 papillary urothelial neoplasia.

The aim of this study was to assess the relationship of immunoreactivity of cytokeratin 20 (CK20) and CD44 across the spectrum of urothelial neoplasia using the WHO/ISUP consensus classification. A total of 120 papillary urothelial pTa and pT1 tumors (8 papillomas, 8 neoplasms of low malignant potential, and 42 low-grade and 62 high-grade carcinomas) were immunostained by using CK20 and CD44 antibodies. The relationships of tumor grade, pathologic stage, recurrences, and progression in stage with CK20 and CD44 immunoreactivity were assessed. WHO/ISUP grade correlated with tumor stage (P < 0.005), recurrence (P = 0.02), and progression in stage (P = 0.031). Normal urothelium showed CK20 immunoreactivity restricted to a few umbrella cells. Expression of CD44 in normal urothelium was restricted to the basal cell layer. Loss of CD44 immunoreactivity and increasing CK20 positivity were significantly associated with increasing tumor grade and stage (P < 0.005). An inverse relationship was observed in the staining patterns of CK20 and CD44 within individual cases, as well as in the aggregate data, with 79.2% of tumors with CD44 loss showing CK20 positivity (P < 0.001). In conclusion, CK20 and CD44 immunoreactivity are significantly related to the WHO/ISUP grade and to each other, and our data suggest their potential combined utility in predicting biologic behavior in patients with papillary urothelial pTa and pT1 neoplasms.

Adult↗

Initial experience of the ORATEL computerised information tools in general practice.

ORATEL (a telematic system for quality assurance indicators in oral health care) is a three-year project with the ultimate objective of improving the quality of oral health care through the use of appropriate computerised information systems. These tools are designed to promote quality assurance and quality of care development in oral health care by using common quality indicators/standards. ORATEL has developed three prototypes of computerised information systems: an interactive multimedia teach software on quality assurance in oral health care, ORATEL-TEACH; a proactive quality assurance support tool for real time use at the dental unit, ORATEL-PROACT; and an integrated set of modules for monitoring and self assessment at the clinical level and for the computerised reporting of aggregated data for evaluation at higher levels, ORATEL-REVAL. The initial experiences of using these tools was assessed during 1993 in general dental practice locations in Liverpool and clinics in for other European countries. Overall, the dentists were positive about the potential usefulness of the ORATEL tools but further improvements were considered necessary. Finding has been approved by the European Commission for further development under a new project called ORQUEST.

Computer Communication Networks↗

Income differences in food consumption in the 1995 Australian National Nutrition Survey.

OBJECTIVE: To assess the relationships between an index of per capita income and the intake of a variety of individual foods as well as groups of food for men and women in different age groups. DESIGN: Cross-sectional national survey of free-living men and women. SUBJECTS: A sample of 5053 males and 5701 females aged 18 y and over who completed the Australian National Nutrition Survey 1995. METHODS: Information about the frequency of consumption of 88 food items was obtained. On the basis of scores on the Food Frequency Questionnaire, regular and irregular consumers of single foods were identified. The relationships between regularity of consumption of individual foods and per capita income were analysed via contingency tables. Food variety scores were derived by assigning individual foods to conventional food group taxonomies, and then summing up the dichotomised intake scores for individual foods within each food group. Two-way ANOVA (income x age group) were performed on the food variety scores for males and females, respectively. RESULTS: Per capita income was extensively related to the reported consumption of individual foods and to total and food group variety indices. Generally, both men and women in low income households had less varied diets than those in higher-income households. However, several traditional foods were consumed less often by young high-income respondents, especially young women. CONCLUSIONS: Major income differentials in food variety occur in Australia but they are moderated by age and gender. Younger high-income women, in particular, appear to have rejected a number of traditional foods, possibly on the basis of health beliefs. The findings also suggest that data aggregation has marked effects on income and food consumption relationships.

Adolescent↗