Testing efficacy with detection controlled estimation: an application to telemedicine.

Detection controlled estimation (DCE) is a powerful new econometric estimator in the family of missing data estimators. By collecting measures from a variety of inspectors or inspection technologies, DCE is able to make inferences about the entire population, even when that population is not directly observed. Using this innovative method, we were able to assess whether telemedicine technology could be substituted for in-person visits when providing maintenance care for patients with hypertension. Our findings indicate that there is no support for the proposition that telemedicine is less effective than in-person visits for determining whether patients have high blood pressure. Indeed, our results imply that telemedicine misses 7% fewer cases of high blood pressure than in-person visits do. The results of this study indicate that DCE may be an effective tool for use in cost-effectiveness or cost-benefit analysis in health care.

Predictors of costs of caring for elderly patients discharged with heart failure.

BACKGROUND: Investments in programs to improve outcomes and reduce readmissions for patients who survive hospitalization with heart failure will be economically most favorable for those who have the highest risk. Little information is available, however, to stratify the risk of these patients incurring costs after discharge. In this study, we sought to determine correlates of costs in a representative sample of patients with heart failure in the 6 months after discharge. METHODS: We reviewed medical records of 2181 patients aged > or = 65 years who were discharged alive from 18 Connecticut hospitals in 1994 and 1995 with a principal discharge diagnosis of heart failure. Outcomes 6 months after discharge, including all-cause readmission and cost, heart failure-related readmission and cost, and death, were obtained from the Medicare administrative database. A 2-stage sample selection model was used to identify the independent correlates of cost. Risk scores were calculated to identify subsets of patients at risk for generating high costs. RESULTS: On average, patients discharged with heart failure incurred costs of $2388 resulting from heart failure-related admissions and $7101 resulting from admissions from any cause during the 6 months after discharge. An average admission for heart failure cost $7174, whereas an admission resulting from any cause cost $8589. The multivariate models explained 7% of the variation in cost, although clinical characteristics such as recent heart failure admissions, kidney failure, and hypertension were significant independent correlates of increased cost. Older age and a history of stroke were independently associated with decreased cost. Patients without any of the risk factors associated with increased costs still incurred $1500 to $5000, on average, in the 6 months after discharge. CONCLUSIONS: Patients with heart failure generate substantial hospital costs in the 6 months after discharge. Given the emerging evidence for effective programs to reduce readmission, investments in interventions that produce even modest reductions in risk would be economically favorable.

Quality of medical care and excess mortality in older patients with mental disorders.

BACKGROUND: This study investigated whether differences in quality of medical care might explain a portion of the excess mortality associated with mental disorders in the year after myocardial infarction. METHODS: This study examined a national cohort of 88 241 Medicare patients 65 years and older who were hospitalized for clinically confirmed acute myocardial infarction. Proportional hazard models compared the association between mental disorders and mortality before and after adjusting 5 established quality indicators: reperfusion, aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and smoking cessation counseling. All models adjusted for eligibility for each procedure, demographic characteristics, cardiac risk factors and history, admission characteristics, left ventricular function, hospital characteristics, and regional factors. RESULTS: After adjusting for the potential confounding factors, presence of any mental disorder was associated with a 19% increase in 1-year risk of mortality (hazard ratios [HR], 1.19; 95% confidence interval [CI], 1.04-1.36). After adding the 5 quality measures to the model, the association was no longer significant (HR, 1.10; 95% CI, 0.96-1.26). Similarly, while schizophrenia (HR, 1.34; 95% CI, 1.01-1.67) and major affective disorders (HR, 1.11; 95% CI, 1.02-1.20) were each initially associated with increased mortality, after adding the quality variables, neither schizophrenia (HR, 1.23; 95% CI, 0.86-1.60) nor major affective disorder (HR, 1.05; 95% CI, 0.87-1.23) remained a significant predictor. CONCLUSIONS: Deficits in quality of medical care seemed to explain a substantial portion of the excess mortality experienced by patients with mental disorders after myocardial infarction. The study suggests the potential importance of improving these patients' medical care as a step toward reducing their excess mortality.

Correlates and impact on outcomes of worsening renal function in patients > or =65 years of age with heart failure.

1.5 mg/dl. Based on the number of these factors, a patient's risk for developing worsening renal function ranged between 16% (< or =1 factor) and 53% (> or =5 factors). After adjusting for confounding effects, worsening renal function was associated with a significantly longer length of stay by 2.3 days, higher in-hospital cost by $1,758, and an increased risk of in-hospital mortality (odds ratio 2.72; 95% confidence interval 1.62 to 4.58). In conclusion, worsening renal function, an event that frequently occurs in elderly patients hospitalized with heart failure, confers a substantial burden to patients and the healthcare system and can be predicted by 6 admission characteristics.

Under-utilisation of beta-blockers after acute myocardial infarction. Pharmacoeconomic implications.

We reviewed the literature on the efficacy and effectiveness of beta-blocker therapy and examined the economic consequences of under-utilisation. Despite the literature documenting the value of beta-blockers, the therapy is not prescribed at the appropriate rates. Approximately half of acute myocardial infarction (AMI) survivors who are eligible for the therapy do not receive it. There are 3 sources of costs that may arise from such under-utilisation: (i) increased morbidity and mortality associated with under-use; (ii) increased demand for related medical resources when the health state following an AMI is suboptimal due to under-use of beta-blocker therapy; and (iii) increased cost due to substitution of higher cost and/or less effective treatments for beta-blockers. For the first category, there is evidence suggesting that around 2900 to 5000 lives are lost in the US in the first year following an AMI due to underprescription. There is very little evidence on the second category of costs; 1 recent study does address this issue and indicates that beta-blocker therapy can lead to a 22% relative risk reduction for hospital readmission during the first year. Several studies also show a decrease in reinfarction. There is no information that addresses the third category of costs adequately (though 1 study does present evidence of substitution of calcium channel-blockers for beta-blockers). We conclude that there is a dearth of evidence on the economic consequences of the under-utilisation of beta-blocker therapy. What does exist suggests that the net costs to society may be substantial.

Variations in and correlates of length of stay in academic hospitals among patients with heart failure resulting from systolic dysfunction.

OBJECTIVE: Given the high cost of caring for patients with congestive heart failure, there are strong incentives to decrease hospital costs by shortening length of hospital stay. We sought to identify factors associated with length of stay among patients admitted for the treatment of heart failure resulting from systolic dysfunction. STUDY DESIGN: Retrospective cohort study. METHODS: We examined data from patients with a principal discharge diagnosis of congestive heart failure who had been admitted to 1 of the 49 academic hospitals across the United States that participated in the CHF Benchmark Project, a large collaborative quality improvement project coordinated by the University HealthSystem Consortium. Patients were discharged between January 1 and June 30, 1996. We obtained patient characteristics and hospitalization data by retrospectively reviewing medical records. We used linear regression models to identify major determinants of length of stay. RESULTS: Among the 1046 patients eligible for the study, 59% were women, 55% were white, and 58% were aged 65 years or older. Adjusting for patient demographic and admission clinical characteristics, the mean length of stay was 4.9 +/- 0.9 days. Length of stay varied significantly among hospitals, even after adjusting for differences in patient characteristics. In multivariate regression models, factors that were independently associated with a significantly longer length of stay were prior renal failure, peripheral edema, atrial fibrillation, hyponatremia, urinary catheter on admission, initiation of an antiarrhythmic or warfarin, and major complications. Patient characteristics and hospital events combined explained 16% of the variation in the length of stay. Adjusting for the individual hospitals explained an additional 10% of the variation in the length of stay. CONCLUSIONS: Although a number of patient and hospitalization factors were associated with length of stay in patients with congestive heart failure resulting from systolic dysfunction, much unexplained variation remained. Clinical factors alone explained about 50% more variation than did factors specific to the individual hospitals.

Relative inefficiencies in production between solo and group practice physicians.

Health economists have hypothesized for some time that physicians produce medical care in an inefficient manner. Further, whether solo or group practice physicians are relatively more inefficient has been a question of particular interest. Theoretical considerations suggest that solo and group practice physicians face different behavioural and production constraints, implying that they may produce care at different levels of efficiency; which is more efficient is an empirical question. We employed stochastic production frontier estimation to address this issue.

Career characteristics of graduates of a Medical Scientist Training Program, 1970-1990.

PURPOSE: To describe the career characteristics of the graduates of the Medical Scientist Training Program (MSTP) at Duke University School of Medicine. METHOD: Surveys and information at administrative offices were used to collect data on all the 1970-1990 MSTP graduates in the summer of 1995. Of the 147 graduates, all but three had completed postgraduate training. In addition, data were available for 35 recent graduates (1991-1995), most of whom were in transition from training and fellowship positions to career positions. RESULTS: Of the 144 graduates from 1970 through 1990, 84 (58%) had selected careers in internal medicine or pathology. A total of 106 (74%) were involved in careers in academic medicine or research. Of these, 87 (82%) held full-time faculty appointments and devoted major efforts to basic or clinical research. Of this group, 59 (68%) were primary investigators receiving grant support from the National Institutes of Health (NIH). Of the 12 women graduates, 11 had careers in academic medicine or research, and seven were primary investigators on NIH grants. At the present time, 11 of 43 (26%) of the matriculating MSTP students are women. Five of the seven underrepresented-minority students in the MSTP have entered in the last five years. CONCLUSION: This study reinforces and extends previous conclusions concerning the success of federally funded MSTPs in producing physician scientists who compete favorably for NIH funding.

Infantile sialic acid storage disease: a rare cause of cytoplasmic vacuolation in pediatric patients.

We report a case of infantile sialic acid storage disease (ISSD) in a black infant presenting in utero with nonimmune hydrops, ascites, and anemia requiring intrauterine transfusion. Upon birth, the patient had prominent edema, large anterior fontanelle, partial absence of the rectus abdominis, clubbing of the left foot, gingival hypertrophy, short first metatarsals, prominent scrotal raphe, right heart dilatation, and left ventricular dysfunction. Radiographs showed pulmonary hypoplasia and epiphyseal stippling. He died of respiratory failure at day 2. Autopsy demonstrated capillary hemangiomata, remote cerebral hemorrhages, and central nervous system periventricular leukomalacia, as well as severe cardio- and hepatosplenomegaly. Multiple single membrane-limited vacuoles consistent with enlarged lysosomes were present in virtually all cell types examined, with striking involvement of liver, myocardium, and placenta. Vacuolar contents were not identifiable by electron microscopy. Demonstration of elevated free sialic acid in urine, amniotic fluid, and cultured fibroblasts confirmed the diagnosis of ISSD. Characteristics of sialic acid storage diseases and their diagnosis are reviewed. ISSD should be considered in infants with empty cytoplasmic vacuoles in multiple tissue types.

Solo versus group practice in the medical profession: the influence of malpractice risk.

While Partnerships are a significant form of business organization in many sectors of the economy, relatively little is known about the incentives which lead to their formation. This paper explores the formation of partnerships among office based physicians when facing some risk of malpractice litigation. Theoretical results indicate that malpractice exposure can increase the incentives to shirk within a partnership, and so exert a significant influence on the decision to form a partnership. Empirical results find that malpractice risk has the expected negative effect on some partnership formation.

Coexisting endogenous and exogenous lipoid pneumonia and pulmonary alveolar proteinosis in a patient with neurodevelopmental disease.

We report a unique case of coexisting exogenous lipoid pneumonia, endogenous lipoid pneumonia (ELP), and pulmonary alveolar proteinosis (PAP) in a 5-year-old patient with severe neurodevelopmental disease. The patient presented with gastroesophageal reflux and presumed chronic lung disease resulting from recurrent aspiration pneumonias and succumbed to respiratory failure. The autopsy showed lipid-laden macrophages and periodic acid-Schiff-positive granular material in alveolar spaces and multilamellated structures within both alveolar macrophages and extracellular debris. These findings were similar to those in previous reports of coexisting ELP and PAP in the setting of gastroesophageal reflux. However, the present case differed by the presence of scattered large osmiophilic extracellular lipid vacuoles. Besides strengthening the association between ELP and PAP and their relationship to gastroesophageal reflux, this case suggests that they may arise together with exogenous lipoid pneumonia, through related mechanisms, in the setting of neurodevelopmental disease.

Endocardial fibroelastosis with coronary artery thromboembolus and myocardial infarction.

We report a case of an 18-month-old male, born to a woman with third trimester febrile illness, who had a history of congestive heart failure and respiratory distress, cardiomegaly, and electrocardiographic (ECG) findings suggestive of cardiomyopathy and myocarditis. After gradual improvement in heart size and function with pharmacologic therapy, he developed a terminal episode of respiratory distress and cardiogenic shock, with ECG findings of an anterolateral infarct. At autopsy it was found that endocardial fibroelastosis with mural thrombi in the left ventricle had been complicated by thromboembolism to the left anterior descending coronary artery, resulting in transmural infarction of the anteroseptal region of the left ventricle. Myocardial infarction is a potential but unusual thromboembolic complication of endocardial fibroelastosis. A high index of suspicion for coronary artery thromboemboli should be maintained in pediatric patients with cardiomyopathy and suspected myocardial infarction.

Variant of atelosteogenesis? Report of a 20-week fetus.

We report on a 20-week fetus with manifestations similar, but not identical, to those of atelosteogenesis. The present fetus had rhizomelic micromelia with absence of ossification in the humerus, radius, ulna, and cervical and upper thoracic vertebral bodies; coronal clefts in the ossified thoracic vertebral bodies; and talipes equinovarus. The physes were relatively normal on histologic examination.

Study of required clerkships in internal medicine in U.S. and Canadian medical schools.

The authors studied teaching of clinical skills and the supervision of clinical education of undergraduate medical students by reviewing students' patient-related experiences in required internal medicine clerkships in the United States and Canada during the 1979-1982 accreditation cycle of the Liaison Committee on Medical Education. The reported patient-related experiences of 180 medical students from 42 medical schools who took histories and performed physical examinations on 2,891 patients formed the basis of this paper. Variability in clerkship length, time worked, supervision, and patient mix suggests that additional quantitative data should be sought on medical students' experiences during the clerkship.

Rocky mountain spotted fever: hepatic lesions in childhood cases.

We studied 16 fatal childhood cases of Rocky Mountain spotted fever (RMSF). Hepatic histologic lesions with statistically significant differences from age- and sex-matched controls were portal triaditis consisting of polymorphonuclear leukocytes and large mononuclear cells, portal vasculitis, sinusoidal leukocytosis, erythrophagocytosis by Kupffer cells, and gross hepatic weight. Hepatocellular necrosis, cholestasis, and congestion were not more frequent in RMSF than in controls. Using immunofluorescence microscopy, we were able to demonstrate rickettsial organisms in portal blood vessels and sinusoidal lining cells of 7 cases.

Pulmonary pathology of Rocky Mountain spotted fever (RMSF) in children.

Despite infrequent respiratory symptoms, histopathologic changes were identified in the lungs of 15 of 16 children dying of Rocky Mountain spotted fever (RMSF). Gross examination demonstrated increased lung weight, edema, congestion, focal hemorrhage, and bronchopneumonia in a few cases. Paraffin sections were stained with hematoxylin and eosin and phosphotungstic acid-hematoxylin, and available blocks were examined by direct immunofluoresence for Rickettsia rickettsii. Cases and controls matched for age and sex were randomized and examined blindly for pathologic changes. In addition, morphometric measurements of mean alveolar septal thickness were made in each case. The histopathologic findings include (1) diffuse interstitial mononuclear (lymphocyte and macrophage) inflammatory infiltrate in 15/16 cases of RMSF (5/10 controls), (2) pulmonary edema and intraalveolar hemorrhage in 11/16 cases of RMSF (2/10 controls), and (3) vasculitis of small pulmonary venules and arterioles in 5/16 RMSF cases (0/10 controls). Rickettsia rickettsii were identified in 4/8 RMSF cases by direct fluorescent antibody technique. Although pulmonary disease is not always clinically apparent in children with RMSF, involvement of the pulmonary microcirculation is a frequent event in fatal cases and may contribute to the development of non-cardiogenic pulmonary edema.

Multiple congenital septal atresias of the intestine: histomorphologic and pathogenetic implications.

Congenital atresias of the gastrointestinal tract are usually single and divided into three forms on a morphologic basis. The septal or diaphragmatic type (type I) is the least common. We report an infant with multiple type I atresias involving both the small and large intestine and describe the unique histologic features of the septa: fragmentation of muscularis mucosa, multiple septal cysts lined by columnar epithelium, circular and longitudinal muscular layers, and absence of inflammation. This infant had a sibling who died with multiple intestinal atresias of the septal type. The histologic features suggest that type I gastrointestinal atresias may be due to failure of complete recanalization rather than result from healing of vascular of inflammatory events.