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Monitoring and reporting alcohol and drug use trends in California: the California Substance Abuse Research Consortium meetings.

For over 15 years, a semiannual meeting sponsored by the California Department of Alcohol and Drug Programs has served as a forum for aggregating data from a variety of sources to examine and monitor the fluctuations in the type, amount, and consequences of alcohol and drug use in California. These meetings of what is now called the Substance Abuse Research Consortium (SARC) have provided California policymakers with an ongoing mechanism for the compilation and sharing of epidemiological information on California alcohol and drug use trends. The tradition of SARC is based on collecting and reviewing epidemiological information: that is, the communication of trends and patterns of alcohol and drug use, emerging drug combinations, shifting user demographics, and new user populations. This article presents a historical perspective of the evolution of the group started under the name "The Statewide Epidemiology Work Group (SEWG)" to its current status as SARC (a more comprehensive history of SARC appears in an article by Anglin and Urada in this issue). It also provides a summary snapshot of the current substance abuse situation in California through the use of substance-related statistics and regional reports.

California↗

Determinants of hospitalisation rates: does primary health care play a role?

OBJECTIVE: To analyse the influence of rates of general practitioner visits on rates of hospitalisations. DESIGN: Ecological cross-sectional study of factors influencing hospitalisation rates. Aggregated data on primary care centre area level. SETTING: The county of Ostergötland, Sweden, with 3 hospital districts and 41 primary health care centres, and the hospital district of Jönköping in the county of Jönköping, Sweden, with 11 primary health care centres. OUTCOME MEASURE: Hospitalisation rates. RESULTS: Age and rates of outpatient hospital visits were the most important factors explaining the variation in rates of hospitalisations between the primary health care centre areas. Hospital districts, socioeconomic factors and rates of GP visits also influenced the rates of hospitalisations. CONCLUSION: When evaluating the influence of primary health care on the rates of hospitalisations, both socioeconomic factors and health care structure must be taken into consideration. Doing this, the rates of GP visits correlated negatively with the rates of hospitalisations.

Aged↗

Mailed prescriber feedback in addition to a clinical guideline has no impact: a randomised, controlled trial.

OBJECTIVE: To evaluate the impact of feedback on the prescribing of antibiotics supplementary to clinical guidelines in the treatment of respiratory tract infections. DESIGN: Randomised, controlled trial with GPs allocated to one of two groups. The first group received clinical guidelines on the treatment of respiratory tract infections plus postal feedback with aggregated data on their prescribing patterns for antibiotics. The second group served as controls for the first group and received the guidelines only. SETTING: 299 GPs representing 181 practices with 455,843 listed patients in the County of Funen, Denmark. MAIN OUTCOME MEASURES: Effects on GP prescribing patterns were measured by means of a prescription database and followed for a period of 2 years with 2 outcome measures: 1) the antibiotic prescription rate and 2) the fraction of prescriptions for narrow-spectrum antibiotics. RESULTS: The addition of feedback had no impact on GP prescribing patterns. CONCLUSION: Postal disseminated prescriber feedback in addition to a clinical guideline on the diagnosis and treatment of respiratory tract infections does not influence GP prescribing patterns. Interventions aimed at improving performance in general practice should go beyond just giving GPs information on whether they are living up to standards.

Anti-Bacterial Agents↗

Alcohol and suicide in Switzerland--an aggregate-level analysis.

At the aggregate-data level, time-series analysis of annual data for the period 1950-90 gives little support for a relation between alcohol consumption and suicide in Switzerland. Input series in the analysis were per capita consumption and rates of unemployment and divorce. Output series were gender-specific and age-adjusted suicide rates. Different time-series techniques were used to assure stationarity and to avoid spurious correlation because of common trends. The Box-Jenkins approach on differenced data was compared with simultaneous equation modelling, where time trends were modeled by means of dummy variables. The effects were weak and unstable for different methods. The advantage of simultaneous equation models is discussed. Furthermore, a single "harmonic" long-term wave explained more of the variance in the suicide rates than any input variable examined. Its implication for a "natural suicide rate" is considered.

Journal Article↗

Development of a microscale emission factor model for CO for predicting real-time motor vehicle emissions.

The U.S. Environmental Protection Agency's (EPA) National Exposure Research Laboratory has initiated a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source through the air pathway to human exposure in significant microenvironments of exposure. This paper presents the technical description of a newly developed model for CO emissions. The sensitivity analysis and evaluation of this emission model is presented in a companion paper titled "Sensitivity Analysis and Evaluation of MicroFacCO: A Microscale Motor Vehicle Emission Factor Model for CO Emissions." The MOBILE models (used in the United States, except California) and EMFAC models (used in California only) used to estimate emissions are suitable for supporting mostly regional (county)-scale modeling and emission inventory because of their dependence on vehicle-miles-traveled aggregate data. These emission models are not designed to estimate real-time emissions needed for human exposure studies near roadways. A number of independent studies have found that current mobile source emission factor models are not very reliable at estimating microscale emissions and are, therefore, inappropriate for use with microscale modeling necessary to estimate human exposures near roadways. A microscale emission factor model for predicting real-world real-time motor vehicle CO emissions (MicroFacCO) has been developed. It uses available information on the vehicle fleet composition. The algorithm used to calculate emission factors in MicroFacCO is disaggregated based on the on-road vehicle fleet. The emission factors are calculated from a real-time fleet rather than from a fleet-wide average estimated by a vehicle-miles-traveled weighting of the emission factors for different vehicle classes. MicroFacCO uses the same database used to develop the MOBILE6 model. As compared with MOBILE emission models, MicroFacCO requires only a few input variables, which are necessary to characterize the real-time fleet being modeled. The main input variables required are on-road vehicle fleet, time and day of year, ambient temperature, and relative humidity.

Carbon Monoxide↗

Does vitamin D deficiency account for ethnic differences in tuberculosis seasonality in the UK?

OBJECTIVES: Notifications of tuberculosis in England and Wales are reported to peak in the summer season. The purpose of this study was to confirm that finding and to determine to what extent patients of Indian Subcontinent (ISC) ethnic origin contributed to the seasonality. The clinical presentation of the disease is presumed to occur some months following reactivation of the endogenous latent focus of tuberculosis infection. There arises the possibility of vitamin D deficiency producing immunological inadequacy at the end of winter and beginning of spring. PATIENTS AND METHODS: Monthly (or 4-weekly) aggregated data over 7 years were collected from the three countries of mainland Britain, England, Wales, Scotland and from the city of Birmingham in England. The notifications from Birmingham were divided into those of ISC ethnic origin and 'whites'. The presence or absence of seasonality was determined by fitting a sinusoidal curve by the technique called 'cosinor analysis'. In this method amplitude gives a measure of the extent of the seasonal variation. RESULTS: The summer peak of clinical diagnosis was confirmed in the UK series from England, Wales and Scotland. In England and Wales without Scotland a larger seasonal variation was present. Scotland, with a lower proportion of population of ISC ethnic origin, was examined separately and the results in Scotland alone failed to confirm seasonality. In the data from Birmingham, seasonality was confirmed with a greater amplitude, particularly in those over 60 years of age. The finding was influenced by those of ISC ethnic origin, seasonality not being present in the 'white' population. CONCLUSION: The results from Birmingham are very striking, but there were almost three times as many patients in the ISC ethnic group as in indigenous 'white' patients. A series with larger numbers of 'white' patients would be necessary to confirm the absence of seasonality in the 'white' population. The discussion reviews the evidence that vitamin D may have an important hormonal role in immunological defence in the prevention of tuberculosis.

Causality↗

The influence of obstetric intervention on trends in twin stillbirths: United States, 1989-99.

OBJECTIVE: Although twin stillbirth rates have declined substantially over the past two decades, the contribution of changes in obstetric interventions to reducing twin stillbirths has not been quantified. METHODS: We carried out a retrospective cohort study of twin live births and stillbirths in the United States between 1989 and 1999 (n=1,102,212). Changes in the rate of stillbirth (> or =22 weeks) before and after adjustment for changes in labor induction, Cesarean delivery and sociodemographic factors were estimated through ecological logistic regression analysis. This analysis was based on aggregating data by each state within the United States. RESULTS: Between 1989 and 1999, rates of labor induction and Cesarean delivery among twin live births increased by 138% (from 5.8% to 13.8%) and 15% (from 48.3% to 55.6%), respectively. These changes were accompanied by a 43% decline in the stillbirth rate between 1989 and 1999 (from 24.4 to 13.9 per 1000 fetuses at risk). After excluding births weighing < 500 g, rates of labor induction among twins at 22-27 weeks', 28-33 weeks' and > or =34 weeks' gestation increased by 95%, 131% and 127%, respectively, between 1989 and 1999. Cesarean delivery rates also increased by 55%, 29% and 2% in these same gestational age categories. The 48% (relative risk (RR) 0.52, 95% confidence interval (CI) 0.49-0.55) decline in stillbirth rate between 1989-91 and 1997-99 was reduced to a 25% (RR 0.75, 95% CI 0.72-0.79) decline after adjustment for changes in labor induction and Cesarean delivery. The decline in the rate of twin stillbirths was larger at later gestational ages (at > or =32 and > or =34 weeks) where the largest absolute increases in labor induction rates were observed. CONCLUSIONS: The use of Cesarean delivery and especially labor induction for twin pregnancies has increased substantially in the United States over the last decade and these changes have been associated with a large decline in the rate of stillbirth among twins.

Adolescent↗

Changes in the association of low birth weight with socioeconomic status in Hawaii: 1970-1990.

This study examines rates of low birth weight (LBW) in the state of Hawaii and changes in the association of LBW with socioeconomic status from 1970 to 1990. The analysis is based on aggregate data for census tracts. Rates of low birth weight were calculated for each census tract. Relative socioeconomic scores were calculated from average household income and years of education. The results show that (1) there was a decrease in the rate of low birth weight infants in Hawaii; and (2) that the correlation between socioeconomic status and low birth weight was substantially reduced, though a significant correlation remains. The paper suggests likely ceiling effects, but that the progressive public health policies and expansion of access to primary health care in Hawaii during this period played a major role in reducing the rate of low birth weight infants and in decreasing socioeconomic inequality on this important health indicator.

Educational Status↗

A new circulating recombinant form, CRF15_01B, reinforces the linkage between IDU and heterosexual epidemics in Thailand.

HIV-1 subtype B and CRF01_AE have been in circulation in Thailand and Southeast Asia for more than a decade. Initially separated by risk group, the two strains are increasingly intermixed, and two recombinant strains of essentially reciprocal structure have been recently reported. Here we identify additional CRF_01B recombinants and provide the evidence that HIV-1 strains now pass freely between the two high-risk populations. HIV isolates that showed discordance between CRF01_AE and subtype B in multi-region genotyping assays were selected for the study. They were drawn from 3 different cohorts in Thailand representing different risk behaviors and demographic characteristics: a drug user cohort in the north, a family planning clinic attendee cohort in the southeast, and a cohort study of the mucosal virology and immunology of HIV-1 infection in Thailand. The DNA from these isolates was PCR amplified to recover the full HIV-1 genome and subjected to sequencing and phylogenetic analysis. We establish that one particular CRF_01B recombinant, with the external envelope of subtype B and the rest of the genome from CRF01_AE, is circulating widely in Thailand. Termed CRF15_01B (also referred to as CRF15), the strain was primarily heterosexually transmitted, although injecting drug use (IDU) also played a role. In aggregate data from the studies, CRF15 constituted 1.7% of all HIV-1 infections (95% confidence interval 0.5-4.4%) and was dispersed widely in the country. The previously separate heterosexual and IDU epidemics have apparently been bridged by a new CRF. The entry of CRF15 into the mainstream of the epidemic signals new complexity in the long stable molecular picture in Thailand. These recombinants must be considered in ongoing or projected efficacy evaluations of HIV-1 vaccines and antiviral therapies.

Adult↗

Price elasticities for three types of CAM services: Experiences of a Boston Public Health Clinic.

OBJECTIVES: This paper addresses price elasticity, an indicator for the responsiveness of demand for healthcare to changes in price, in the context of a large public health clinic that provides acupuncture, Chinese herbal medicine, and shiatsu. DESIGN: The study is descriptive and observational. The observations resulted from a "natural experiment" and involved examining utilization before and after a 5 dollars(17%) price increase for all services. Aggregate data were collected on demographics and utilization of 222 clients using services over a 6-month period in 2004. SETTING: Pathways to Wellness is a nonprofit agency that provides complementary and alternative medicine (CAM) services to underserved, low-income clients. The agency administers a clinic that has been operating for the past 15 years and currently provides approximately 1200 treatments per month. OUTCOME MEASURES: Utilization data on number of treatments administered were collected for 3 months prior to the price increase and compared to utilization data for the 3 months after the price increase. Comparisons were made for both the immediate changes in utilization (2-month data) and quarterly changes in utilization (6-month data). RESULTS: Utilization dropped for all three services in the month after the price increase. Values of elasticity associated with the immediate changes were calculated as -0.35 for acupuncture services, -1.31 for Chinese herbal consultations, and -2.34 for shiatsu services, and indicate a wide range of responsiveness. CONCLUSIONS: Values of price elasticities indicate a range of differential responses to change in price for services. The relatively smaller drop in utilization of acupuncture services may be consistent with clients' perceptions of effectiveness or immediacy of treatment symptom relief.

Acupressure↗

Evidence for the systemic delivery of a transgene product from salivary glands.

The aim of this study was to assess the feasibility of using gene transfer to salivary glands to direct the systemic delivery of therapeutic proteins in vivo. We used a replication-deficient recombinant adenovirus vector (Ad alpha 1AT) that encodes human alpha 1-antitrypsin (h alpha 1-AT), which we used as a marker protein. Ad alpha 1AT (5 x 10(9) pfu) was administered by retrograde ductal instillation to the submandibular glands of male rats. The amount of h alpha 1-AT found in the salivary glands, saliva, serum, and other tissues was analyzed by a sensitive enzyme-linked immunosorbent assay (ELISA). Maximal levels of the marker protein were detected at 24-48 hr post-virus administration for glands (274 ng/mg protein), saliva (approximately 313 ng/ml), and serum (approximately 5 ng/ml). Serum levels remained elevated for 96 hr, whereas the measured half-life for the marker protein was approximately 2 hr. Generally little to no h alpha 1-AT was detectable in most other organs. However, we were able to measure low levels of marker protein in tissues immediately surrounding infected glands. In all animals studied, levels of h alpha 1-AT were higher in the glandular venous effluent than in arterial blood. Similar results were found with parotid glands. The aggregate data demonstrate that salivary glands may be a target for the nonsurgical, systemic delivery of transgene-encoded therapeutic proteins for diseases that require relatively low circulating protein levels.

Adenoviruses, Human↗

Promoting excellence in end-of-life care: a report on innovative models of palliative care.

BACKGROUND: Promoting Excellence in End-of Life Care, a national program of The Robert Wood Johnson Foundation, funded 22 demonstration projects representing a wide range of health care settings and patient populations to develop innovative models for delivering palliative care that addressed documented deficiencies in the care of patients and families facing the final stage of life. OBJECTIVE: To determine the practicality (feasibility of development and operation as well as acceptance by stakeholders) of new models of care and to determine the impact of the models on access to, quality of and financing for palliative care. DESIGN: The program cannot report scientifically rigorous outcomes, but the grant-funded projects used a variety of methods and measures to assess acceptance of new models and their impact from the perspectives of various stakeholders, including patients and their families, clinicians, administrators and payers. While it is not possible to aggregate data across projects, the data reported to the Promoting Excellence national program office were used to describe program impact with respect to the practicality of palliative care service integration into existing clinical care settings (feasibility and acceptance by stakeholders), the availability and use of palliative care services (access), quality of care (conformance to patient expectations and accepted clinical standards) and costs of care. SETTINGS AND SUBJECTS: The 22 projects provided services in urban as well as rural settings, in integrated health systems, hospitals, outpatient clinics, cancer centers, nursing homes, renal dialysis clinics, inner city public health and safety net systems and prisons. Populations served included prison inmates, military veterans, renal dialysis patients, Native Americans, Native Alaskans, and African American patients, inner-city medically underserved patients, pediatric patients, and persons with serious mental illness patients. RESULTS: Hosting or adopting institutions sustained or expanded twenty of the 22 models, and feedback from all stakeholders was positive. Project sites developed and utilized new palliative care services and addressed quality through implementation of new standards and clinical protocols. Costs of care, where they could be assessed, were unaffected or decreased for project patients versus historical or concurrent controls. CONCLUSIONS: The 22 Promoting Excellence in End-of Life Care projects demonstrated that by individualizing patient and family assessment, effectively employing existing resources and aligning services with specific patient and family needs, it is possible to expand access to palliative services and improve quality of care in ways that are financially feasible and acceptable to patients, families, clinicians, administrators, and payers.

Feasibility Studies↗

Reengineering a pharmacist intervention program.

At the beginning of a period of rapid growth in clinical pharmacy services in our integrated health system, we realized that there was no mechanism to address how pharmacist interventions were processed, evaluated, and followed up. Interventions were inconsistently documented, and the documentation served no more purpose than to record workload statistics. There was little assessment of the value or quality of interventions, no peer review, and no reporting of aggregate data to improve system-related problems. How are others handling the documentation and assessment of pharmacist interventions?

Documentation↗

Insights on bias and information in group-level studies.

Ecological and aggregate data studies are examples of group-level studies. Even though the link between the predictors and outcomes is not preserved in these studies, inference about individual-level exposure effects is often a goal. The disconnection between the level of inference and the level of analysis expands the array of potential biases that can invalidate the inference from group-level studies. While several sources of bias, specifically due to measurement error and confounding, may be more complex in group-level studies, two sources of bias, cross-level and model specification bias, are a direct consequence of the disconnection. With the goal of aligning inference from individual versus group-level studies, I discuss the interplay between exposure and study design. I specify the additional assumptions necessary for valid inference, specifically that the between- and within-group exposure effects are equal. Then cross-level inference is possible. However, all the information in the group-level analysis comes from between-group comparisons. Models where the group-level analysis provides even a small percentage of information about the within-group exposure effect are most susceptible to model specification bias. Model specification bias can be even more serious when the group-level model isn't derived from an individual-level model.

Analysis of Variance↗

Treatment of cutaneous leishmaniasis with allopurinol and stibogluconate.

We conducted a randomized, controlled study in southern Colombia to determine if the addition of allopurinol to stibogluconate was superior to stibogluconate alone in the treatment of cutaneous leishmaniasis. Lesions that healed after a 3-month course of therapy and remained so during a 1-year period of follow-up were considered cured. The cure rate for patients treated with stibogluconate was 39%; the addition of allopurinol increased this rate to 71% (P = .005). For the treatment of cutaneous leishmaniasis, the combination of allopurinol and stibogluconate is significantly more effective than is stibogluconate alone. These results support those of other clinical studies in which allopurinol and stibogluconate were shown to be superior to stibogluconate alone. The aggregate data support the use of allopurinol as an inexpensive, orally administered agent that can be used as an adjunct to stibogluconate or, perhaps, other oral agents in the treatment of cutaneous leishmaniasis.

Adolescent↗

Economic burden of cardiovascular diseases in the enlarged European Union.

AIMS: Cardiovascular disease (CVD), together with its main components, coronary heart disease (CHD), and cerebrovascular diseases, is the main source of morbidity and mortality in the European Union (EU), but to date, there has not been any systematic cost-of-illness study to assess the economic impact of CVD in the EU. METHODS AND RESULTS: CVD-related expenditure was estimated using aggregate data on morbidity, mortality, and healthcare resource use. Healthcare costs were estimated from expenditure on primary, outpatient, emergency, and inpatient care, as well as medications. Costs of unpaid care and lost earnings due to morbidity and premature death were included in the study. CVD was estimated to cost the EU Euro 169 billion annually, with healthcare accounting for 62% of costs. Productivity losses and informal care represented 21% and 17% of costs, respectively. CHD represented 27% and cerebrovascular diseases 20% of overall CVD costs. CONCLUSION: CVD is a leading public health problem. Our study is the first to assess the economic burden of CVD across the EU, and our results should help policy makers evaluate policy impact and prioritize research expenditures. However, because of data unavailability, our study has important limitations, which highlight the need for more accurate and comparable CVD-specific information.

Cardiovascular Diseases↗

Better by half: hypertension in the elderly and the 'rule of halves': a primary care audit of the clinical computer record as a springboard to improving care.

BACKGROUND: Despite recent studies highlighting the benefits of treating elderly hypertensives, researchers have shown that the taking on board of these findings has been disappointing in primary care, where the 'rule of halves' still applies. Clinical computers could help performance in this area, yet national and local research suggests that they are under-used. OBJECTIVE: Our aim is to develop a pragmatic intervention which aims to: improve patient care by translating research findings into practice, increase meaningful computer use, establish 'paperless' annual audits and improve 'networking' between practices. METHOD: Following a baseline audit to ascertain accuracy, the computer records of participating practices were tested against the 'rule of halves' for hypertension. Results were presented to each practice (individual practice and aggregate data for all practices). Management guidelines, standardization of computer recording, achievable targets and review dates were agreed. The study was conducted in West London practices using the EMIS computer system in 1996/1997. RESULTS: An 81% (22/27) practice response rate was achieved. Baseline audit was completed for 22 practices. Fifteen practices appear to be using their computer regularly (two-thirds). Using strict definitions, 'the rule of halves' still applies. Using looser definitions, three-quarters of hypertensives are known, two-thirds are treated and just under two-thirds are controlled. This project identified wide inter- and intra-practice variation in: use of the computer, patient follow-up, attainment of target BP, rounding BP readings to target levels and prescribing patterns. CONCLUSION: This focused training intervention has introduced practices to evidence-based proactive care and highlighted an important application for clinical computers. A local network of practices has been established for future projects. For elderly patients registered with a GP, the rule of halves has been improved upon, provided that a figure of 160/90 is taken as an adequate control. Attainment of target BP in treated hypertensives was similar to that reported from large trials. There is enormous scope for improving identification and follow-up of hypertensives using clinical computers and systematic models of care. The wide inter-practice variation in hypertension management requires further study.

Aged↗

The effects of membership in church-related associations and labor unions on age differences in voluntary association affiliations.

PURPOSE: When compositional differences between age groups are controlled, the bivariate, curvilinear pattern of age differences in voluntary association memberships is replaced by one in which peak membership levels occur in late middle age and remain relatively stable thereafter. We sought to determine if this adjusted pattern persists when widespread memberships in two types of associations are removed: (1) church-related organizations, in which membership increases with age but may be confounded with church membership per se; and (2) labor unions, in which membership is also widespread but may not be "voluntary." DESIGN AND METHODS: Total memberships in 14 types of associations were examined using aggregated data from 12 national surveys conducted between 1974 and 1994. RESULTS: The familiar curvilinear relationship at the bivariate level appears, but in the multivariate analysis, membership levels rise from ages 18-24 through 55-59 and persist close to that level through ages 85 and older. IMPLICATIONS: The results reaffirm that age differences in voluntary association affiliations are due to age-based compositional differences; they also show, however, that the pattern observed with controls is neither driven by membership in church-related "associations" nor altered when membership in labor unions is excluded.

Adolescent↗