Biomedical subjects

R D Horner

Publications and source records attributed to R D Horner.

At least 55 records · Page 3Linked to original sources

PubMed1995

The influence of history on interobserver agreement for diagnosing actinic keratoses and malignant skin lesions.

BACKGROUND: Quantifying interobserver diagnostic agreement is necessary to evaluate skin cancer screening programs, but estimates of variability are incomplete. OBJECTIVE: We sought to measure agreement between dermatologists for diagnosing actinic keratoses (AKs) and malignant skin lesions and to determine the way in which blinding examiners to patient history affects agreement. METHODS: We varied the amount of historical information available to examiners in two consecutive patient series (n = 50) presenting to a Veterans Affairs Medical Center dermatology clinic. Two dermatologists examined each patient independently. RESULTS: Assessing historical features increased the kappa statistic for malignancy recognition from -0.04 to 0.76. kappa Statistics for diagnosing single AKs were 0.17 and 0.15, respectively, and 0.62 and 0.55 for multiple AKs. CONCLUSION: Agreement was high for diagnosing malignant skin lesions when history was included in the evaluation. Agreement for multiple AKs was higher than for single AKs, although neither was influenced by inclusion of historical features.

Aged↗

PubMed1995

Patterns of care for and outcomes of Pneumocystis carinii pneumonia among persons with transfusion-acquired AIDS.

BACKGROUND: The most common human immunodeficiency virus (HIV)-related cause of death in persons with transfusion-acquired (TA) AIDS has been Pneumocystis carinii pneumonia (PCP). While better treatment for PCP accounts for improved survival among HIV-infected homosexual or bisexual men, the extent to which others have benefitted from these developments is unknown. STUDY DESIGN AND METHODS: Patterns of PCP care among persons with TA-AIDS, intravenous drug users, and homosexual or bisexual men are compared. RESULTS: TA-AIDS patients were older (mean, 46 years vs. < 40 for others, p < 0.05), more severely ill (59% had an alveolar-arterial oxygen gradient > 48.5 torr vs. 41% of others, p < 0.05), and less likely to have received PCP prophylaxis (16% of TA-AIDS patients versus 24-41% of others, p < 0.05). PCP care and outcomes also differed: TA-AIDS patients were less than half as likely to have early use of PCP medications (relative odds ratio = 0.45; 95% CI, 70% vs. > 80% for others, p < 0.05), more likely to be intubated (22% vs. 9-13% of others, p < 0.05), and more likely to die in-hospital (26% vs. 13-22% of others, p < 0.05). After controlling for differences in severity of illness, insurance, age, and hospital characteristics, TA-AIDS patients were 45 percent as likely to have early PCP therapy (95% CI, 22%, 91%) as were persons in high-risk groups. CONCLUSION: For persons whose only risk factor was transfusion, recognition of the HIV infection and its complications appears to be problematic, which may help explain poorer outcomes in persons with HIV-related PCP.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Empirically treated Pneumocystis carinii pneumonia in Los Angeles, Chicago, and Miami: 1987-1990.

Many patients infected with the human immunodeficiency virus (HIV) with symptoms suggestive of pneumonia are treated empirically for Pneumocystis carinii pneumonia (PCP), although other bacterial infections (e.g., tuberculosis) and pulmonary Kaposi's sarcoma may cause identical symptoms. Empiric treatment for PCP may result in misdiagnosis and mistreatment. When the outcomes of cytologically confirmed versus empirically treated PCP cases were evaluated, the most important predictors of in-hospital mortality were severity of illness and use of bronchoscopy. Persons who did not undergo bronchoscopy had higher mortality rates than patients negative by bronchoscopy or cytologically confirmed as positive for PCP (22% vs. 11% vs. 14%, P < .01), although severity of illness and timing of anti-PCP medications did not differ significantly. Compared with cytologically confirmed cases, persons who did not have bronchoscopy were more likely to die than were bronchoscopy-negative patients (P < .05), after adjusting for severity of illness. Bronchoscopy use may have contributed to better outcomes for persons treated for HIV-related PCP.

AIDS-Related Opportunistic Infections↗

PubMed1995

Relationship between procedures and health insurance for critically ill patients with Pneumocystis carinii pneumonia.

The objective of the present study was to assess the association between type of health insurance coverage and use of diagnostic tests and therapies among patients with AIDS-related Pneumocystis carinii pneumonia (PCP). Fifty-six private, public, and community hospitals in Chicago, Los Angeles, and Miami were selected for the study, and the charts of 890 patients with empirically treated or cytologically confirmed PCP, hospitalized during 1987 to 1990 were retrospectively reviewed. Patients were classified by insurance status: self-pay (n = 56), Medicaid (n = 254), or private insurance, including health maintenance organizations and Medicare (n = 580). Primary outcomes were the use and timing of bronchoscopy, the type and timing of PCP therapy, and in-hospital mortality. The results indicate that Medicaid patients were less likely than privately insured patients to undergo bronchoscopy (relative odds = 0.61; 95% CI = 0.40, 0.93; p = 0.02) or to have their diagnosis of PCP confirmed (relative odds = 0.51; 95% CI = 0.33, 0.77), after adjusting for patient, severity of illness, and hospital characteristics. Medicaid patients were approximately three-fourths more likely than privately insured patients (relative odds = 1.73; 95% CI = 1.01, 2.96; p = 0.04) to die in-hospital, after adjusting for patient, severity of illness, and hospital characteristics. However, with further adjustment for confirmation of PCP, Medicaid patients no longer had a significantly higher likelihood of dying in-hospital. We conclude that Medicaid patients are less likely to receive diagnostic bronchoscopy than privately insured or self-insured patients, more likely to be empirically treated for PCP, and more likely to die in-hospital.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗

PubMed1995

Theories explaining racial differences in the utilization of diagnostic and therapeutic procedures for cerebrovascular disease.

Despite a higher risk of stroke, blacks are less likely than whites to receive the invasive procedures that are used to diagnose and treat cerebrovascular disease, particularly carotid endarterectomy. Explanations for the lower rate of procedural use include racial bias, racial differences in pathophysiology of cerebrovascular disease, affordability, and racial variation in patient decisions regarding care. Studies consistently indicate that blacks are less likely to have severe atherosclerotic lesions of the carotid arteries, reducing their likelihood of being appropriate candidates for carotid endarterectomy. Although ability to pay does not explain the observed variation in use of carotid endarterectomy, it may influence the evaluation process prior to hospitalization. A racial difference in patients' decisions about health care for cerebrovascular disease has never been investigated; it should be a topic of future studies.

Black or African American↗

PubMed1995

Relationship between physician specialty and the selection and outcome of ischemic stroke patients.

OBJECTIVE: This study compares the initial characteristics, in-hospital treatment, and outcomes of stroke patients managed by neurologists versus non-neurologists. DATA SOURCES/STUDY SETTING: An inception cohort of 146 patients hospitalized with their first stroke at a private, a university, or a Veterans Affairs hospital. STUDY DESIGN: A prospective, hospital-based, multisite cohort study design is used to ascertain the patients' initial 180-day in-hospital and postdischarge experience. DATA COLLECTION/EXTRACTION METHODS: Data were collected on patient demographics, disease severity, and risk factors for stroke; diagnostic tests and pharmacologic management; one-month and six-month all-cause and cause-specific mortality; and physical and functional impairment. PRINCIPAL FINDINGS: The 88 patients (60 percent) admitted to the neurology services of the study hospitals had better prognostic profiles, i.e., lower likelihood of having either completed stroke or cardiac comorbidity, and were less likely to die within one and six months of stroke onset. CONCLUSIONS: Substantial systematic differences in the types of patients managed by neurologists versus other specialists may preclude comparison of outcomes of care.

Activities of Daily Living↗

PubMed1994

Effect of oral magnesium supplementation on selected cardiovascular risk factors in non-insulin-dependent diabetics.

OBJECTIVE: To evaluate the impact of oral magnesium supplementation on risk factors for end-organ disease in patients with non-insulin-dependent diabetes mellitus (NIDDM). DESIGN: A 16-week randomized, double-blind, placebo-controlled crossover trial. SETTING: Outpatient center of an academic family medicine residency program. PATIENTS: Twenty-eight patients (age range, 28 to 84 years; 57.1% black; 85.7% women) with NIDDM controlled by diet and/or an oral hypoglycemic, with a serum cholesterol levels over 5.20 mmol/L (200 mg/dL). INTERVENTION: Following a 2-week placebo run-in period, each patient was randomized to receive either sustained-release magnesium chloride (Slo-Mag), 384 mg/d, or an identical-appearing placebo for 6 weeks. After a 2-week interim washout period, each patient was then treated with the alternative regimen for an additional 6-week period. MAIN OUTCOME MEASURES: The systolic and diastolic blood pressure and levels of serum glucose, low-density and high-density lipoprotein and total cholesterol, triglycerides, and serum and total erythrocyte magnesium were measured at the beginning, midpoint, and end of each 6-week treatment phase. RESULTS: Systolic blood pressure fell an average of 7.4 mm Hg (P < .05) with treatment. There was no significant change in diastolic blood pressure or levels of serum glucose, low-density and high-density lipoprotein and total cholesterol, triglycerides, or serum and erythrocyte magnesium. CONCLUSIONS: Oral magnesium supplementation in the doses and duration studied is modestly effective in reducing systolic blood pressure in patients with NIDDM but has little impact on other important biochemical parameters related to diabetes-associated end-organ disease.

Administration, Oral↗

PubMed1994

Similar motor recovery of upper and lower extremities after stroke.

BACKGROUND AND PURPOSE: This study examined the validity of the clinical tenet that poststroke recovery of the upper extremity is less rapid and complete than poststroke recovery of the lower extremity. Previous studies comparing upper and lower extremity recovery have evaluated disability rather than motor impairment. Individuals with lower extremity impairments may be more functional and appear less disabled than individuals with upper extremity impairments. Function of the upper extremity requires finer motor control, for which the patient can less readily compensate. Therefore, impairments and disability would predictably be more highly correlated in this area. We tested the hypothesis that upper and lower extremity motor recovery are similar. METHODS: The 95 patients selected for this study were enrolled in the Durham County Stroke Study and had been diagnosed with anterior circulation ischemic stroke. Each subject received Fugl-Meyer assessments within 24 hours of admission and then 5, 30, 90, and 180 days after stroke. We used these assessments to compare the time course and patterns of motor function of the upper and lower extremities. RESULTS: Repeated-measures ANOVA revealed that percent maximal motor recovery was significantly (P < .001) affected by time after stroke but not by extremity (upper extremity versus lower extremity) (P = .32). When stroke severity level is controlled, the upper and lower extremities continue to show no difference in percent motor recovery (P = .19). CONCLUSIONS: In patients with anterior circulation ischemic stroke, the severity of motor impairment and the patterns of motor recovery are similar for the upper and lower extremities. The most rapid recovery for both extremities occurs within 30 days.

Aged↗

PubMed1994

Racial differences in rural adults' attitudes toward issues of adolescent sexuality.

This study, based on a random sample of adults in a rural North Carolina county, demonstrates racial differences in rural adults' attitudes relating to adolescent sexual issues. Blacks were 50% more likely than Whites to indicate that public schools should provide general health care services, including pregnancy testing and treatment of sexually transmitted diseases, to teenagers; however, they were only half as likely as Whites to approve of sexual experimentation by adolescents. The local community's attitudes must be considered in the implementation of rural adolescent health programs, including acquired immunodeficiency syndrome education.

Abortion, Induced↗

PubMed1993

Racial variations in the rates of carotid angiography and endarterectomy in patients with stroke and transient ischemic attack.

BACKGROUND: Carotid endarterectomy is emerging as the treatment of choice for patients with symptomatic carotid artery stenosis at low operative risk. We sought to determine if racial variations in the rate of carotid angiography and endarterectomy exist in the Veteran Affairs health care system among patients who are insulated from the cost of their care. METHODS: From a national database of all hospitalizations at Veterans Affairs medical centers, we identified a cohort of patients with diagnoses of stroke or transient ischemic attack who were likely to be candidates for carotid angiography and endarterectomy. We used logistic regression to determine if the patient's race was associated with receiving carotid angiography and endarterectomy, after adjusting for patient's age, degree of eligibility for Veterans Affairs care, socioeconomic status, comorbidities associated with hospital admission, and geographic region of the hospital. RESULTS: Of the 35 922 veterans in the cohort, 3535 (9.8%) underwent angiography during the study period and 1249 (3.5%) had carotid endarterectomy. Blacks constituted 18.2% of the patients with a history of stroke or transient ischemic attack, 9.8% of the patients having angiography, but only 4.2% of the patients undergoing carotid endarterectomy. Whites constituted 77.1% of the patients with a history of stroke or transient ischemic attack, 86.1% of the patients receiving angiography, and 93.0% of those having carotid endarterectomies. After adjusting for confounding variables, black patients continued to have a significantly lower likelihood than white patients of undergoing angiography (risk ratio = 0.47; 95% confidence interval = 0.42, 0.53) and subsequent endarterectomy (risk ratio = 0.28; 95% confidence interval = 0.20, 0.38). CONCLUSIONS: Socioeconomic status and access to care within a large managed health care system do not fully explain racial differences in the rate of carotid angiography and endarterectomy. Either referral bias for evaluation for carotid endarterectomy or racial differences in the extent and location of cerebrovascular disease are more important explanations for the observed racial variations.

Aged↗

PubMed1993

Preliminary evidence on retention rates of primary care physicians in rural and urban areas.

The primary study objectives were to 1) determine how many physicians entered primary care practice in rural and urban counties of North Carolina in the 1981 to 1989 period and 2) estimate their length of tenure in these areas. The secondary objective was to identify the physician's demographic, training, and practice characteristics that influence geographic location of practice and length of tenure. A cohort of 1,947 physicians was identified from the North Carolina Board of Medical Examiners database, which included all active, nonfederal primary care physicians who began their initial practice in North Carolina in 1981 or later. The primary outcome was time in practice in a given rural or urban county. Selected data on physician demographic, training and practice characteristics were also available in the database. Approximately one third of physicians beginning their initial North Carolina practice selected a rural county for the location. Almost half of these primary care physicians were still in the county of their initial practice in 1989. An additional 20% of these physicians had changed practice location within the State, of which half chose a similar type of county to that of their initial practice. Length of tenure was similar across geographic locations of the medical practice, with the average length of tenure being 4.6 and 4.4 years among physicians in rural and urban counties, respectively. The strongest predictors of tenure were practice organizational characteristics with physicians in either an office-based solo practice or partnership having longer tenures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Criteria for the use of Sartwell's incubation period model to study chronic diseases with uncertain etiology.

This study explores the conditions under which Sartwell's incubation period model may be appropriate for identifying a primary time period of etiologic risk for chronic diseases with uncertain etiology. The investigation begins with a description of the evolution of the application of Sartwell's model from infectious to chronic diseases. The model's underlying assumptions and some concerns about its use in the chronic disease context are specified. These concerns are addressed by data simulations and analyses of empirical data from the Connecticut Tumor Registry and the Radiation Effects Research Foundation. The results indicate that the distribution of age at diagnosis (i.e. onset) for chronic diseases is not necessarily lognormal. However, the representativeness of age distribution of the case series can affect the distribution's form; hence, it is important to determine the extent of "missing" cases, particularly those lost through truncation. Moreover, a lognormal age distribution may occur with both prenatal and age-related postnatal exposures. These findings suggest that only under certain conditions will Sartwell's model be useful in the study of chronic diseases of uncertain etiology, and indicate some caveats for interpretation of the results.

Chronic Disease↗

PubMed1992

Nutritional status and dietary intake of children with sickle cell anemia.

The nutritional status and dietary intake of children with sickle cell anemia were examined to confirm the presence of deficiencies. Nine children with sickle cell anemia and 19 controls were assessed. Resting energy expenditure was measured with open circuit indirect calorimetry and body composition was estimated from skinfold measurements. Three-day food records were analyzed for protein, zinc, vitamin A, folic acid, and iron content. Serum vitamin A, red blood cell zinc, red blood cell folate, serum folate, serum ferritin, hematocrit, total urine nitrogen, and 24-h urine creatinine levels were measured. The children with sickle cell anemia were leaner, weighed less, and had lower red blood cell zinc levels, lower serum vitamin A levels, lower urine nitrogen levels, and greater resting energy expenditure than controls. Serum and red blood cell folate levels were within normal ranges and similar to controls. The serum ferritin level was higher than controls and higher than normal for age. Dietary intake of energy and protein was more than that of controls, and dietary intake of zinc, vitamin A, folic acid, and iron was similar to that of controls and adequate compared to the Recommended Dietary Allowances. Further studies are needed to explain the physical and biochemical differences seen in children with sickle cell anemia despite dietary intakes that appear to be adequate and similar to those of controls.

Anemia, Sickle Cell↗

PubMed1992

Designing and evaluating an episodic, problem-based geriatric curriculum.

BACKGROUND: Medical school geriatric training has been directed primarily at improving students' attitudes and knowledge about elderly patients. This study evaluated a clinical problem-based geriatric course for medical students. METHODS: The two-semester geriatric course was presented to 136 second-year medical students. Faculty taught students about clinical reasoning in ambulatory geriatrics using written cases, patient-actors, literature reviews, lectures, and discussions. At the end of the course, students' clinical activity was evaluated using audiotaped interviews with standardized geriatric patients. A questionnaire examined students' knowledge, attitudes, and their evaluation of the course. RESULTS: All 136 students completed the post-course standardized patient interview, and 105 (77%) completed questionnaires. Students rated the course favorably and had high confidence scores for ability to assess geriatric problems. Students' knowledge increased during the course compared to a precourse examination (P less than .05). Evaluation of post-course standardized patient interviews revealed that students who scored higher on the knowledge test tended to ask more psychosocial questions during the interview (r = 0.38). Students who scored higher on the attitude test spent more time eliciting patients' feelings during the interview (r = 0.38). Those with lower scores on the attitude test spent more time asking factual, nonpsychosocial questions (r = 0.28). CONCLUSIONS: A clinical problem-based geriatric course for preclinical medical students can be successful in improving students' knowledge. Attitudes and knowledge effect the questions a student asks during the medical interview.

Attitude of Health Personnel↗

PubMed1992

The effect of tissue disaggregation methods on the clonogenicity of solid human tumor cells.

The effect of mechanical, enzymatic and combined disaggregations on the same tumor tissue (n = 154) to define variables related to clonogenic efficiency (CE) of human tumor clonogenic assay (HTCA) was examined. Overall, CE was highly associated with the percentage of malignant cells in the inoculative suspensions (P less than 0.001) and the total cell concentration plated (P = 0.03). However, there was no significant correlation between CE and the disaggregation method, type of tumor, cell viability, proportion of macrophages in the inoculum, or length of incubation (10 or 20 days). In addition, a higher CE was found in some nonadherent fractions when comparing the CE of the original plating suspensions to that of their nonadherent fractions. It is concluded that mechanical disaggregation is the simplest technique for obtaining the highest yield of malignant cells, which is a decisive factor for colony growth, and that an incubation time of 10 days and 1 x 10(6) cells per plate is the best condition for the human tumor clonogenic assay.

Gastrointestinal Neoplasms↗

PubMed1991

Racial variations in ischemic stroke-related physical and functional impairments.

BACKGROUND AND PURPOSE: We sought to determine whether there are racial differences in physical and functional impairments resulting from an initial ischemic stroke. METHODS: We conducted a prospective, county-wide, multisite cohort study including a university hospital, a community hospital, and a Veterans Affairs hospital. The study population was an inception cohort of 145 patients hospitalized for ischemic stroke. Physical and functional impairments were measured using a modified form of the Fugl-Meyer test and the Barthel Index, respectively. Nurses trained to use these tests made assessments at admission and 5, 30, 90, and 180 days after admission. Patient and disease-specific data along with treatment data and vital status were collected. RESULTS: Forty-one patients (28%) were black. Compared with whites, black stroke patients were more likely to be widowed (51% versus 26%) and hypertensive (83% versus 63%) but less likely to be male (42% versus 69%) and alert on admission (66% versus 76%). There were no racial differences in mortality. Physical impairment was significantly more severe in black than in white patients at admission, and although physical impairment improved, it remained significantly worse in blacks. Functional impairment was also greater in black patients initially but was similar to that in white patients 90 days after the event. Multivariable analyses confirmed these findings. CONCLUSIONS: These results indicate that blacks may have greater residual physical deficits from stroke than whites.

Activities of Daily Living↗

PubMed1991

Accuracy of patient encounter and billing information in ambulatory care.

BACKGROUND: This study examined the degree of accuracy of billing data in an academically affiliated family practice. METHODS: The progress notes from 1253 consecutive visits were independently reviewed by two family physicians, and the diagnoses, use of procedures, and level of service were determined for each visit. Discrepancies between the reviewers were resolved by consensus. These data were compared with the data on the corresponding billing form that had been completed by the care providers (ie, physicians on the faculty, physicians in training, family nurse practitioners, and nurses). RESULTS: There was poor agreement between the billing form and progress note on level of service and number of diagnoses (kappa = 0.37 and kappa = 0.28, respectively). The progress note usually indicated that a higher level of service should have been billed for a visit than actually was billed. Underreporting of the number of diagnoses was substantial; the billing forms listed only 69% of the diagnoses identified in the progress notes. In 60% of visits, each diagnosis on the billing form had a matching diagnosis in the progress note. This could be improved to 78% of visits if broad categories of disease were used. Residents were similar to faculty in the accuracy of reported level of service and types of diagnoses, but were more likely to underreport the number of diagnoses. CONCLUSIONS: Ambulatory care data from computerized billing files may not be sufficiently accurate for proper reimbursement of physician services or for use in research.

Abstracting and Indexing↗

PubMed1991

Pica practices of pregnant women.

This report summarizes current knowledge about pica practices during pregnancy through a systematic review of the literature for the period 1950 through 1990. Pica behavior was considered in terms of its prevalence, risk factors, clinical profile, and effect on pregnancy outcome. Data on pica practices by pregnant women are limited and inconclusive but reveal several interesting relationships. The prevalence of pica among pregnant women in high-risk groups declined between the 1950s and the 1970s but now remains steady, affecting about one fifth of high-risk women. Women at high risk of pica are more likely to be black, to live in rural areas, and to have a positive childhood and family history of pica. The clinical picture of the disorder during pregnancy is not well described. The evidence suggests that pica during pregnancy results in anemia, but it is not definitive. Pica also has been associated with maternal and perinatal mortality. We conclude that the behavior is more prevalent than commonly believed, shows no sign of further decline, and may have serious effects, particularly anemia, on mother and infant. Dietetic practitioners who counsel pregnant women should ask questions about pica when they conduct nutrition assessments of their clients.

Black or African American↗