父母的母语与儿童预防性医疗行为的差异有关

目的:研究父母的母语为非英语的婴儿比父母的母语为英语的婴儿是否更不易接受推荐的预防性医疗行为。研究设计:笔者对1999年1月1日至2000年9月30日期间在华盛顿州出生的所有38793例参加医疗救助的1岁婴儿进行回顾性组群研究。主要因素为自己报告的父母的母语。笔者使用多参数回     

Depression in Medicaid-covered youth: differences by race and ethnicity

BACKGROUND: Racial disparities have previously been noted in antidepressant use among Medicaid-covered youth. OBJECTIVE: To determine if racial and ethnic differences are due to dissimilarity in the prevalence of diagnosed depression or disparate treatment patterns. METHODS: Claims were examined for 192 441 youth (5-18 years old) who had been continuously enrolled in Medicaid from July 1, 1997, to December 31, 1998. Diagnosed depression was defined as having been assigned an International Classification of Diseases, Ninth Revision code for a depressive disorder in a medical claim. Logistic regression methods were used to evaluate the association between race/ethnicity and (1) depression diagnosis and (2) depression treatment in the 6 months following a new episode of diagnosed depression. All analyses were controlled for age, sex, and rural or urban residence. RESULTS: Two percent of the total sample had a depression diagnosis, 25% of which were new episodes of depression. Compared with white youth, Hispanic (odds ratio [OR], 0.51; 95% confidence interval [CI], 0.46-0.57), Asian/Pacific Islander (OR, 0.16; 95% CI, 0.12-0.21), and black (OR, 0.31; 95% CI, 0.26-0.37) youth were less likely to have a depression diagnosis. Following a new diagnosis, Native American (OR, 0.29; 95% CI, 0.18-0.46) and Hispanic (OR, 0.42; 95% CI, 0.30-0.61) youth were less likely than white youth to have received an antidepressant or a mental health specialty visit. CONCLUSIONS: Racial and ethnic disparities exist in both the prevalence and treatment of diagnosed depression. Future studies should examine underlying reasons for these disparities and how they affect the quality of care for depressed Medicaid-covered youth.     

The insulin cardioplegia trial: myocardial protection for urgent coronary artery bypass grafting

BACKGROUND: Small, nonrandomized clinical trials have demonstrated a beneficial effect of solutions containing insulin and glucose on the recovery of myocardial metabolism and ventricular function after cardioplegic arrest and reperfusion. However, no large, blinded, randomized study has yet determined the effects of insulin-enhanced cardioplegia on clinical outcomes after coronary artery bypass grafting. METHODS: The Insulin Cardioplegia Trial was designed to evaluate the clinical impact of insulin-enhanced cardioplegia on patients at high risk undergoing isolated coronary artery bypass grafting for unstable angina. A total of 1127 patients were randomly assigned at operation to receive cardioplegic solution supplemented with 10 IU/L insulin (n = 557) or placebo (n = 570). All personnel with direct patient contact were blinded to randomization group. RESULTS: Overall operative mortality was 2.2%, with no significant differences between groups. The prevalences of postoperative low output syndrome (insulin 10.4%, placebo 9.7%, P =.7) and enzymatic myocardial infarction (insulin 21.0%, placebo 18.8%, P =.3) were not different between groups. The primary composite outcome of low output syndrome and/or enzymatic myocardial infarction revealed no difference between groups (insulin 30.0%, placebo 26.3%, P =.2). CONCLUSIONS: Despite encouraging results from smaller, nonrandomized studies, the Insulin Cardioplegia Trial failed to demonstrate a clinical benefit of insulin-enhanced cardioplegic solution for patients undergoing high-risk isolated coronary artery bypass grafting.     

Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant

Background. Although small valve size and patient-prosthesis mismatch are both considered to decrease long-term survival, little direct evidence exists to support this hypothesis.

Methods. To assess the prevalence of patient-prosthesis mismatch and the influence of small valve size on survival, we prospectively studied 1,129 consecutive patients undergoing aortic valve replacement between 1990 and 2000. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography postoperatively (3 months to 10 years). Abnormal postoperative gradients were defined as those patients with mean or peak gradient above the 90th percentile (mean gradient ≥ 21 or peak gradient ≥ 38 mm Hg). Patient-prosthesis mismatch was defined as those patients with indexed effective orifice area below the 10th percentile (< 0.60 cm²/m²).

Results. A multivariable analysis identified internal diameter of the implanted valve as the only independent predictor of abnormal gradients postoperatively. However, there was no significant difference in actuarial survival between normal and abnormal gradient groups (7 years: 91.2% ± 1.5% versus 95.0% ± 2.2%; p = 0.48). Freedom from New York Heart Association class III or IV (7 years: 74.5% ± 3.1% versus 74.6% ± 6.2%; p = 0.66) and left ventricular mass index were not different between normal and abnormal gradient groups. Patients with and without patient-prosthesis mismatch were similar with respect to postoperative left ventricular mass index, 7-year survival (95.1% ± 1.3% versus 94.7% ± 3.0%; p = 0.54), and 7-year freedom from New York Heart Association class III or IV (79.3% ± 6.6% versus 74.5% ± 2.5%; p = 0.40). In patients with patient-prosthesis mismatch and abnormal gradients, the majority had prosthesis dysfunction owing to degeneration.

Conclusions. Severe patient-prosthesis mismatch is rare after aortic valve replacement. Patient-prosthesis mismatch, abnormal gradient, and the size of valve implanted do not influence left ventricular mass index or intermediate-term survival.     

Construct validity of medicare chemotherapy claims: the case of 5FU

BACKGROUND: The elderly are under represented in clinical trials of cancer therapy and the elderly who are enrolled may be unrepresentative. OBJECTIVE: To assess whether Medicare claims data might be used to understand the benefits and tolerance of chemotherapy in the general elderly population, the construct validity of Medicare 5FU claims for elderly colon cancer patients within the SEER-Medicare data set was determined. METHODS: In this validation study of Medicare chemotherapy claims from the linked the SEER-Medicare data set, the patterns of 5FU chemotherapy claims were evaluated for an incident cohort of elderly colon cancer patients (n = 15,039) during the 13 months following their diagnosis. Patterns of Medicare National Claims History (NCH) 5FU claims were evaluated with respect to prespecified patient-level disease and demographic factors from the data set. RESULTS: Twenty-two percent of patients had at least one detectable 5FU claim during the observation period. Among those patients, the median dose of 5FU was 1000 mg, the median interval between 5FU claims was 7 days, and the median number of claims during this period was 24. Multivariate regression revealed expected associations between demographic and disease factors and the likelihood of having a Medicare NCH 5FU claim. With increasing cancer stage, patients' likelihood of having a 5FU claim increased. Younger patients, married patients, white patients, patients with low comorbidity, and patients living in urban and less impoverished regions were each more likely to have 5FU claims. CONCLUSION: Because their pattern is consistent with the standard of medical care and with previously described associations with disease and demographic factors, it was concluded that Medicare NCH claims for 5FU administration in the SEER-Medicare data set exhibit construct validity. Criterion validation studies with an external gold standard should be pursued to determine the sensitivity and specificity of chemotherapy codes in the Medicare NCH files.     

Oxygen extraction in lamb skeletal muscle

Past studies have found that total-body O2 extraction during hypoxia was less in 1-wk-old lambs than in older animals. It was proposed that reduced O2 extraction was secondary to suppression of growth-related oxygen consumption (VO2) in tissues such as skeletal muscle, bone, kidney, and skin, rather than a defect in peripheral O2 use. To determine the capacity of immature skeletal muscle to extract O2, we isolated the hind limb circulation of eight ketamine-anesthetized, 7- to 18-d-old lambs exposed to stagnant hypoxia by inflation of a right atrial balloon catheter. Femoral arterial and venous PO2, PCO2, pH, Hb concentration, O2 saturation, and femoral arterial blood flow (Q) were measured and hind limb O2 delivery (DO2), extraction ratio, and VO2 calculated. Individual critical levels of DO2 below which VO2 was dependent on O2 supply were determined by dual-line best-fit regression analysis. In six of eight animals, VO2 was clearly independent of supply until DO2 reached critically low levels. However, O2 extraction during extreme hypoxia appeared submaximal (baseline O2 extraction ratio, 0.22 +/- 0.06; at critical levels of DO2, 0.51 +/- 0.11; at the lowest level of Q, 0.64 +/- 0.15). When 2,4-dinitrophenol, an uncoupler of oxidative phosphorylation, was administered to four additional lambs exposed to stagnant hypoxia, O2 extraction below critical levels of DO2 increased from 0.48 +/- 0.15 to 0.79 +/- 0.10 (p less than 0.001, unpaired t test). These data suggest that initial limitations in O2 extraction were a result of the suspension of O2-consuming processes, not an irreversible defect in peripheral O2 use.     

Insulin cardioplegia for elective coronary bypass surgery

BACKGROUND: Improved methods of myocardial preservation are required to reduce the morbidity and mortality of coronary bypass surgery for high-risk subgroups. Metabolic stimulation with insulin, glucose solutions, or both has been proposed as a method to preserve the ischemic myocardium. We performed a prospective, double-blind, randomized trial to evaluate the effects of insulin and glucose as cardioplegic additives when used as part of a tepid continuous blood cardioplegic strategy. METHODS: We randomized 56 male patients undergoing elective isolated coronary bypass surgery to 1 of 4 cardioplegic groups containing either 42 or 84 mmol/L glucose with or without 10 IU/L of insulin. Perioperative assessments of myocardial metabolism and left ventricular function were performed. RESULTS: Insulin-enhanced cardioplegia was associated with beneficial effects on both myocardial metabolic and functional recovery after cardioplegic arrest. Insulin's effect was independent of the ambient glucose concentration. CONCLUSIONS: Cardioplegic formulations containing a 42 mmol/L concentration of glucose and a 10 IU/L concentration of insulin provide significant benefit to patients undergoing isolated coronary bypass surgery. The clinical effect of these formulations will need to be assessed in high-risk subgroups of patients, such as those with unstable angina, recent myocardial infarction, or poor left ventricular function.     

Pediatric Hospitalization Patterns for Selected Chronic Health Conditions Using Hospital Abstract Reporting System Data: Methods and Findings

Children with chronic health conditions require more health services than other children and are vulnerable to potential problems of access and appropriateness of care due to rapid changes in the health care system. Methods to measure hospitalization patterns of children for chronic health conditions, a measure of access and utilization, are not well-developed. The objective of this study is to identify hospitalization patterns of children with eight selected chronic health conditions, using hospital abstract reporting system data from Washington state for the ten year period 1987–1996. The methods illustrate an approach to using hospital discharge data for ongoing surveillance of children with special health care needs.A total of 525,113 discharges representing 394,460 individual children ages 0–19 were analyzed in this study. Population-based hospitalization rate per 100,000 population, average length of stay, and rate of multiple hospitalizations per 1000 discharges, were calculated for asthma, diabetes, cystic fibrosis, muscular dystrophy, cerebral palsy, chronic respiratory disease, spina bifida, and malignant neoplasms. The hospitalization rate of 3,019.4 per 100,000 population for all causes among children 0–19 reflected a significant decline since 1987. Mean LOS of 4.9 for all causes in 1996 represented a significant decline from 5.3 in 1987. The multiple hospitalization rate for all causes increased significantly from 250.5 per 1000 discharges in 1987 to 275.5 per 1000 discharges in 1996. Condition-specific comparisons indicated an increase in hospitalization rates for asthma, chronic respiratory disease, and neoplasms, although the LOS declined for diabetes and was unchanged for all other conditions. Multiple hospitalization rates for selected conditions examined in this study did not show an increase in the ten-year period, and for diabetes, showed a statistically significant decline.The refinements in the approach to using hospital discharge data in this study are important tools to be used for pediatric chronic disease surveillance. Further refinements should include adjustments for patient age and condition complexity, as well as stratification by payer and facility.     

The Current Status of Myocardial Revascularization: Changing Trends and Risk Factor Analysis

Abstract From November 1989 to December 1994, we performed 2264 bypass procedures. Data were collected prospectively. The population was divided into three subgroups: group 1 = single internal mammary artery (IMA) ± veins (n = 1584); group 2 = veins only (n = 503); and group 3 = two or more arterial conduits ± veins (n = 177). Patients who received only saphenous vein conduits (group 2) were significantly older (66.7 ± 8.9 years) than either group 1 (60.3 ± 8.3 years) or group 3 (51.6 ± 9.2 years). Furthermore, this cohort group had the highest percentage of females (28.6%), urgent cases (43.5%), preoperative myocardial infarction (MI) (18.5%), and redo surgery (5.4%). In contrast, patients who received two or more arterial conduits were 94.9% male, and had the lowest incidence of urgent cases (18.1%) and redo surgery (0.5%). Mortality was 1.4% in group 1 and 3.2% in group 2; there were no deaths in group 3. Furthermore, group 2 patients had the highest incidence of perioperative MI (6.6%), low output syndrome (22.1%), intra-aortic balloon pump (IABP) assist (6.2%), and stroke (2.7%). By multivariate logistic regression analysis (odds ratio in parentheses), redo surgery (7.92), preoperative IABP (5.53), poor LV function (4.01), renal impairment (3.94), and advanced age (2.12) were all predictors of operative mortality. When mortality and morbidity (death, infarction, low output syndrome, IABP assist) were combined, regression analysis revealed that in addition to the above variables, female gender and cold cardioplegia were also independent predictors of combined mortality and morbidity. Resource utilization was determined for the three patient groups. There was concern that the increased technical demands of multiple arterial grafting along with longer periods of aortic occlusion and pump times may lead to increased complications and prolonged hospital stay. However, we found that group 3 had the lowest ventilation time, intensive care unit stay, and hospital stay. The results no doubt were influenced by case selection. Whether or not this approach to revascularization will increase long-term survival and freedom from reoperation will require further study.     

The origin of the sickle mutation in Greece; evidence from beta S globin gene cluster polymorphisms.

Study of the Hpa I polymorphism 3' to the beta-globin gene in the Greek population revealed absence of the site in 238 beta S chromosomes, in contrast to a much larger sample of chromosomes carrying the beta A gene, where this site was consistently positive. Subsequent haplotype analysis of the beta-globin gene cluster in 82 beta S chromosomes demonstrated that 79 (96%) belonged to haplotype #19, while the three exceptions (all Hpa I negative) could be explained by a delta-beta recombination event. Haplotype #19 was never encountered in a parallel study of the 83 beta A chromosomes. Comparison of the above results with similar surveys in other parts of the world and consideration of various historical events suggest that the beta S mutation was introduced into Greece over the last few centuries by the Saracen raids and/or by settlements of North African slaves brought in by the Arabs, Franks, Venetians, or Ottoman Turks, who have occupied the country over the last millennium.