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B J McNeil

Publications and source records attributed to B J McNeil.

At least 55 records · Page 3Linked to original sources
PubMed1995

Variation in the use of cardiac procedures after acute myocardial infarction.

BACKGROUND: There are large geographic differences in the frequency with which coronary angiography and revascularization are performed. We attempted to assess whether differences in case mix or in the treatment of specific groups of patients may explain this variability. We also assessed the consequences of various patterns of treatment. METHODS: We studied patients covered by Medicare who were 65 to 79 years of age and were admitted to 478 hospitals with acute myocardial infarctions during 1990 in New York (1852 patients), where the rate of use of cardiac procedures is low, and in Texas (1837 patients), where the rate of use of such procedures is high. We compared the patterns of treatment of clinically similar groups of patients in the two states. We also compared mortality rates and measures of the health-related quality of life. RESULTS: Coronary angiography was performed more often in Texas than in New York (45 percent vs. 30 percent, P < 0.001). The frequency of use in Texas was significantly higher than that in New York for all the clinical subgroups of patients analyzed except those at greatest risk for reinfarction. Over a two-year period, the adjusted likelihood of death was lower in New York than in Texas (hazard ratio, 0.87; 95 percent confidence interval, 0.78 to 0.98). Patients from Texas were 41 percent more likely to report angina (P = 0.002) and 62 percent more likely to say they could not perform activities requiring energy expenditure of 5 or more metabolic equivalents than patients from New York approximately two years after infarction (P < 0.001). CONCLUSIONS: Physicians in Texas were more likely to perform angiography than physicians in New York for patients whose conditions allowed more discretion in the use of cardiac procedures. On average, there appears to be no advantage with respect to mortality or health-related quality of life to performing the procedures at the higher rate used in Texas.

Aged↗
PubMed1995

The influence of race on the use of surgical procedures for treatment of peripheral vascular disease of the lower extremities.

OBJECTIVE: To assess whether rates of amputation and leg-sparing surgery for peripheral vascular disease of the lower extremities differ between African-American and white patients. DESIGN: Retrospective cohort study using Medicare claims data for 1989 and 1990. SETTING: A total of 3313 hospitals in the United States. PATIENTS: Random sample of 19,236 Medicare Part A enrollees who underwent amputation and/or leg-sparing surgery for peripheral vascular disease. MAIN OUTCOME MEASURES: Adjusted odds of toe and/or foot amputation, below-knee amputation, above-knee amputation, lower extremity arterial vascularization, and percutaneous transluminal angioplasty for African American relative to whites, controlling for case-mix, region, and hospital characteristics. RESULTS: African-American patients were significantly more likely than white patients to undergo above-knee, below-knee, and toe and/or foot amputation and significantly less likely to undergo lower-extremity arterial revascularization and percutaneous transluminal angioplasty. These associations occurred for diabetic patients and nondiabetic patients but were more pronounced among patients who did not have diabetes. CONCLUSIONS: Potential explanations include unmeasured factors such as severity of disease and the technical expertise available at hospitals or other factors such as lack of compliance with medical treatment and race-specific treatment decisions by providers. Whatever the cause, interventions aimed toward reducing the number of amputations among African Americans are needed. Further work is required to determine where such interventions should be targeted.

Black or African American↗
PubMed1995

The influence of socioeconomic status on change in health status after hospitalization.

We reviewed patients' hospital records and surveyed patients after hospital discharge to determine whether the experience of being hospitalized differentially affected the health status of persons with different socioeconomic backgrounds (as measured by income level and education level) and to determine whether the association between socioeconomic status (SES) and change in health status varied depending upon the reason for hospital admission. We studied patients admitted to six university-affiliated teaching hospitals in Massachusetts and California for chest pain (N = 797) and surgery (N = 1165). We compared the health status scores of patients for a variety of outcomes: basic activities of daily living, instrumental activities of daily living, social activities, mental well-being, work performance and housework performance. Lower-SES patients entered the hospital with worse health status than higher-SES patients. Change in health status, statistically adjusted for case-mix, varied by reason for admission. Patients with chest pain generally reported either no improvement or a decline in functioning with the amount of decline equivalent for low- and high-SES patients. Surgical patients reported improvement in functioning following hospitalization. For several measures, lower-income surgical patients reported greater improvement than did higher-income patients, but still did not reach the same level of health status as higher-income patients.

Activities of Daily Living↗
PubMed1995

Development and validation of a claims based index for adjusting for risk of mortality: the case of acute myocardial infarction.

We developed a comorbidity index on a cohort of 162,699 Medicare beneficiaries who had an acute myocardial infarction (AMI) in 1987 and validate it on two national cohorts: (1) a cohort of 164,427 Medicare beneficiaries who had an AMI in 1988 and (2) a cohort of 10,466 patients admitted to Veterans Administration Hospitals (VAH) for AMI in 1988-1991. The impact of each sensitivity was expressed as; (1) the risk of mortality for those with the comorbidity, (2) the adjustment to the log odds for 2 year mortality and (3) the age-based likelihood of 2 year mortality. Models were validated by calculated the area under an ROC curve obtained by fitting a logistic regression model to each validation population. The two year mortality rate for 30-day survivors was approximately 30% in each of the 3 cohorts. The 5 most prevlent comorbidities coded in the developmental cohort were heart failure (34%), chronic angina (27%), minor arrythmias (25%) and uncomplicated hypertension (18%). Cancer was the most powerful predictor of 2 year mortality, impacting mortality the same as a 18.3 year age increase. Saturation (having all secondary diagnoses in the discharge summary filled) resulted in a 9.2 year age increase. Validation in the 1988 Medicare and in the Veterans Administration Hospitals cohorts resulted in areas of 73% and 72% under the respective ROC curves. Our methods can serve as a prototype for others wishing to assess comorbidity in other targeted subgroups.

Aged↗
PubMed1995

Variations in the utilization of coronary angiography for elderly patients with an acute myocardial infarction. An analysis using hierarchical logistic regression.

This article reports a study of variations in the utilization of angiography for Medicare recipients who had an acute myocardial infarction. The study cohort consisted of 1987 Medicare beneficiaries who had a recent acute myocardial infarction. Variations were examined from three perspectives: patient characteristics, regional practice patterns, and on-site availability of the procedure. Factors associated with variation within and among states were incorporated into the analysis using hierarchical logistic regression models. The probability of angiography during the first 90 days after an acute myocardial infarction was estimated as a function of patient age, gender, race, and comorbidity for patients in 51 states (including the District of Columbia). Interstate differences were examined in relation to geographic region and on-site availability of angiography. Observed rates of angiography ranged between 13.8% and 38.3% (median, 24.7%). Variation was nearly threefold based on estimated state probabilities of angiography for a patient with characteristics set at the national average. Observed and estimated rates were lower in northeastern states than in other parts of the United States. States with more extensive onsite availability of angiography tended to have higher angiography rates after adjusting for patient characteristics and geographic region. Adjusted angiography rates were on average higher for younger patients, males, and nonblacks. There was substantial interstate variation in race differences, with states in the Southeast generally having the largest differences. The adjusted black-to-nonblack odds ratio ranged from a low of 0.41 to a high of 0.94. Interstate variation in age and gender differences was moderate. The work reported in this article illustrates the potential of hierarchical regression modeling as a framework for the analysis of variations and some methodologic issues connected with its implementation. Our results show that large variations in the utilization of procedures can exist, despite uniform insurance coverage and a relatively homogeneous patient cohort. Aggressive use of angiography was highly variable across states as was the degree of access to the procedure for blacks and nonblacks. The state rate of on-site availability of angiography facilities was an important predictor of utilization. Increased on-site availability of angiography, however, was not associated with a reduction of differences in access to the procedure.

Age Factors↗
PubMed1994

Knowledge and practices of generalist and specialist physicians regarding drug therapy for acute myocardial infarction.

BACKGROUND: The respective roles of generalist and specialist physicians in the care of patients is currently a matter of debate. Information is limited about the knowledge and practices of generalist and specialist physicians regarding conditions that both groups treat, such as myocardial infarction. METHODS: We therefore surveyed 1211 cardiologists, internists, and family practitioners in the states of New York and Texas about four treatments demonstrated by randomized clinical trials to be associated with improved survival after myocardial infarction (thrombolytic therapy, immediate and long-term use of aspirin, and long-term use of beta-blockers) and two treatments for which such evidence is lacking (diltiazem for patients with pulmonary congestion and prophylactic lidocaine). We asked physicians about the effect of each treatment on survival and the likelihood that they would prescribe each class of drugs. RESULTS: For the four beneficial treatments, the cardiologists believed more strongly than the internists and family physicians that survival was improved by the treatment, and they were more likely to prescribe these drugs (P < 0.001). For example, 94.1 percent of cardiologists said they were very likely to prescribe thrombolytic agents to treat an acute myocardial infarction, as compared with 82.0 percent of internists and 77.3 percent of family practitioners. Conversely, for the two treatments for which trials showed no evidence of a survival benefit, cardiologists were less likely than internists and family practitioners to think there was such a benefit and less likely to prescribe the drugs (P < 0.001). For example, 4.7 percent of cardiologists reported that they were very likely to use prophylactic lidocaine, as compared with 13.1 percent of internists, and 16.5 percent of family practitioners. When we used logistic regression to adjust for potential confounders, all the differences between the cardiologists and the internists and family practitioners remained significant (P < 0.02). CONCLUSIONS: Internists and family practitioners are less aware of or less certain about key advances in the treatment of myocardial infarction than are cardiologists. This finding underscores the need to improve the dissemination of information from clinical trials to generalist physicians, particularly if they are to have an enlarged role in the evolving health care system.

Adult↗
PubMed1994

Does more intensive treatment of acute myocardial infarction in the elderly reduce mortality? Analysis using instrumental variables.

OBJECTIVE: To determine the effect of more intensive treatments on mortality in elderly patients with acute myocardial infarction (AMI). DESIGN: Analysis of incremental treatment effects using differential distances as instrumental variables to account for unobserved case-mix variation (selection bias) in observational Medicare claims data (1987 through 1991). MAIN OUTCOME MEASURES: Survival to 4 years after AMI. RESULTS: Patients who receive different treatments differ in observable and unobservable health characteristics, biasing estimates of treatment effects based on standard methods of adjusting for observable differences. Patients' differential distances to alternative types of hospitals are strong independent predictors of how intensively an AMI patient will be treated and appear uncorrelated with health status. Thus, differential distances approximately randomize patients to different likelihoods of receiving intensive treatments. Comparisons of patient groups that differ only in differential distances show that the impact on mortality at 1 to 4 years after AMI of the incremental ("marginal") use of invasive procedures in Medicare patients was at most 5 percentage points; this gain was achieved during the first day of hospitalization and therefore appears attributable to treatments other than the procedures. Admission to a hospital treating a high volume of AMI patients was associated with an effect on mortality at 4 years of less than 1 percentage point, again arising on day 1. Patients living in rural areas experienced acute mortality that was an additional 0.6 percentage-point higher, after controlling for less access to intensive treatments. CONCLUSIONS: For elderly patients with AMI, the aspects of treatment most affecting long-term survival relate to care within the first 24 hours of admission. The survival benefits from greater use of catheterization and revascularization procedures appear minimal in marginal patients.

Aged↗
PubMed1994

The influence of age on clinical and patient-reported outcomes after cholecystectomy.

OBJECTIVE: To examine the relationship between the age of cholecystectomy patients and surgical complications, length of stay, symptom relief, and postdischarge functional status. DESIGN: Patients' medical records were reviewed and patients were sent a questionnaire three months after hospital discharge. SETTING: Four university-affiliated teaching hospitals. PATIENTS: 372 patients who had a primary operation of total cholecystectomy. OUTCOME MEASURES: In-hospital complications, length of stay, patient satisfaction, symptom relief, and functional status after discharge. RESULTS: Patients over the age of 60 years experienced a higher major postoperative complication rate than did younger patients (p < 0.01), although the overall major complication rate was too low to determine whether factors other than age were important predictors. There was no age-related difference in minor postoperative complication rates. The older patients had a longer mean length of stay, even after statistical adjustment for covariates (p < 0.05). The older patients reported similar levels of patient satisfaction, but reported recurrence of preoperative abdominal pain less often than did the younger patients (OR = 0.4, 95% CI = 0.2, 0.7). There was no statistically significant difference between the older and younger patients in postoperative functioning, except for work performance. The younger patients reported improvement in postoperative work performance, while the older patients reported a decline (p < 0.01). CONCLUSIONS: Older cholecystectomy patients may experience more postoperative complications but report less recurrence of preoperative abdominal pain than do younger patients. The decline in work performance in older patients may indicate the need for a longer recuperation period.

Age Factors↗
PubMed1994

Trends in the use of drug therapies in patients with acute myocardial infarction: 1988 to 1992.

OBJECTIVES: In this study, we investigated the use of thrombolytic agents and other cardiac drugs in a national cohort of patients with acute myocardial infarction and assessed the influence of large clinical studies on types of thrombolytic therapy prescribed. BACKGROUND: Information about usage patterns for these drugs is unavailable, and little is known about the impact of large clinical trials on their use. METHODS: We conducted a retrospective cohort study of 65,011 patients who were treated for acute myocardial infarction during fiscal years 1988 to 1992 (October 1, 1987 to September 30, 1992) in hospitals participating in the SMS Corporation's on-line data pool. RESULTS: The overall thrombolysis rate for patients with acute myocardial infarction increased from 11% in fiscal year 1988 to 18% in fiscal year 1990 and has remained approximately at that level since then. In mid-1989, tissue plasminogen activator was used in 90% of the patients receiving thrombolysis, whereas streptokinase was used in only 10%. Since 1991, tissue plasminogen activator has been used in 60% of patients and streptokinase in almost 30%. Much of this change came after presentation and publication of results of the Second Gruppo Italiano per lo Studio Della Sopravvivenza nell'Infarto Miocardico (GISSI-2) and the Third International Study of Infarct Survival (ISIS-3) trials. Over these 5 years, use of beta-adrenergic blocking agents increased steadily, and use of calcium-channel blocking agents declined steadily. CONCLUSIONS: Current usage rates of thrombolytic therapy are lower than expected, but trends in usage rates for beta-blockers and calcium channel blockers reflect their increasing and decreasing approval, respectively. Presentation and publication of results from the Third International Study of Infarct Survival and the Second Gruppo Italiano per lo Studio Della Sopravvivenza nell'Infarto Miocardico trials appear to have influenced the type of thrombolytic agent prescribed.

Adrenergic beta-Antagonists↗
PubMed1994

Staging of prostate cancer: results of Radiology Diagnostic Oncology Group project comparison of three MR imaging techniques.

PURPOSE: To assess accuracy of three different magnetic resonance (MR) imaging techniques, including the endorectal coil, in staging prostate cancer. MATERIALS AND METHODS: MR imaging was performed in 213 patients with prostate cancer with a conventional body coil, with fat suppression and a body coil, and with an endorectal coil. Radiologists identified tumor invasion into periprostatic tissues, neurovascular bundles, and seminal vesicles. Each technique was evaluated separately, and in a subset of 74 patients the three techniques were evaluated together. Images obtained with the two body-coil techniques were read in combination with images obtained with the endorectal coil (combination A) and alone (combination B). RESULTS: Overall accuracy for conventional body-coil, fat-suppressed body-coil, and endorectal-coil MR was 61%, 64%, and 54%, respectively. Overall group accuracy for combinations A and B was 57% and 61%. Considerable interreader variability was found for combination A. CONCLUSION: No technique was highly accurate for staging early prostate cancer. Individual radiologists did achieve a high degree of staging accuracy with the endorectal-coil and body-coil combination.

Humans↗
PubMed1994

MR imaging and sonography of early prostatic cancer: pathologic and imaging features that influence identification and diagnosis.

OBJECTIVE: The purpose of this study was to correlate findings at MR imaging and transrectal sonography with histopathologic findings after surgery in patients with prostatic cancer, to identify the pathologic characteristics of prostatic cancer that improved detection with MR imaging and transrectal sonography, and to identify the imaging characteristics that correlated with detection of true cancers. MATERIALS AND METHODS: Data from MR imaging in 320 patients and from transrectal sonography in 343 patients who were enrolled in the Radiological Diagnostic Oncology Group multiinstitutional study of imaging in prostatic cancer were correlated with results of radical prostatectomy. Only cancers 5 mm or greater in at least one dimension were evaluated pathologically. The locations of lesions and the linear dimensions and volumes of individual lesions and the prostate gland were evaluated pathologically and with imaging studies. The appearance of lesion margins on images and the degree of differentiation of lesions seen on pathologic examination were also studied. Univariate and multivariate analysis were performed to determine the pathologic findings associated with imaging detection and the imaging characteristics associated with prostatic cancer. RESULTS: MR imaging and transrectal sonography showed 62% and 64% of cancers, respectively, each with a positive predictive value of 68%. Cancers that were larger, moderately or poorly differentiated, or located in the posterior half of the outer gland were easier to detect (p < .0001). The overall size of the prostate did not effect lesion detection. However, abnormalities identified in the posterior half of the outer gland were more likely to be cancers. On transrectal sonograms, larger abnormalities also were more likely to be malignant tumors. The sharpness of the margins of the imaged abnormalities did not predict pathologic status. CONCLUSION: Detection of prostatic cancer with MR imaging or transrectal sonography is affected by cancer size, differentiation, and location; the odds of an imaged lesion's being malignant are related to location and, for transrectal sonography, size. Knowledge of anatomic/pathologic features that enhance lesion detection may help when using imaging tests to detect prostatic carcinoma. That certain imaging characteristics of lesions are associated with true cancers may assist in the interpretation of MR images and transrectal sonograms of the prostate.

Algorithms↗
PubMed1994

Utility of magnetic resonance contrast agents in routine cranial imaging. Case study of an evaluative method.

Scientific studies that document the utility and value of MR imaging in routine clinical practice must differ from double-blind, randomized clinical trials. The case study in this article represents an effort to create pragmatic methods for these clinical environments. An independent, judicial panel reviewed blinded readings of unenhanced and enhanced MR images. This panel determined that Gd-DTPA enhancement improved the readings that were close enough for clinical purposes--called Diagnostic Merit. More importantly, clinical care was not disrupted, and statistically significant benefits were shown in routine practice. Such studies could lead to earlier reimbursement for useful imaging technologies.

Analysis of Variance↗
PubMed1994

Outcomes research: hope for the future or the latest rage?

Outcomes research is a broad term. It involves not only investigations of the link between medical care and outcomes, but also activities aimed at assessing quality of care. The number of individuals and organizations involved in outcomes research has grown rapidly over the past decade. Despite this activity, some observers question whether outcomes research can deliver on its promises. In this paper, we define the scope of outcomes research and then discuss its potential for fulfilling the expectations of various stakeholders who have played a role in its design and implementation.

Cost Control↗
PubMed1993

Temporal changes in the care and outcomes of elderly patients with acute myocardial infarction, 1987 through 1990.

OBJECTIVE: To investigate changes between 1987 and 1990 in the care and outcomes associated with acute myocardial infarction (AMI) in elderly patients. DESIGN: Retrospective cohort study using a longitudinal database created from Medicare administrative files. PATIENTS: Cohorts comprising a total of 856,847 AMI patients insured by Medicare between 1987 and 1990. MAIN OUTCOME MEASURES: Annual rates of mortality at 30 days and 1 year following AMI, and the use of coronary angiography, coronary artery bypass graft surgery, and percutaneous transluminal coronary angioplasty during the first 90 days after a new AMI. RESULTS: Between 1987 and 1990, mortality rates decreased 10% overall from 26% to 23% at 30 days (P < .001) and from 40% to 36% at 1 year following AMI (P < .001). Declines in mortality and adjusted risks of 1-year mortality were similar in men and women and in blacks and whites, but mortality declines were more evident in those younger than 85 years. Meanwhile, the proportion of elderly AMI patients having angiography within the first 90 days after their index admission increased from 24% to 33% (P < .001); proportions increased for both genders and all races. The proportion of patients undergoing revascularization procedures increased from 13% to 21%; while rates of bypass surgery increased from 8% to 11%, rates of angioplasty doubled from 5% to 10% (all P < .001). CONCLUSIONS: Between 1987 and 1990, survival of elderly patients following AMI improved significantly. While changes in patient treatment may be responsible, the increased use of thrombolytic therapy appears to be only a partial explanation. Also, while the use of coronary angiography and revascularization procedures increased dramatically, the degree to which it caused the improvement in survival could not be determined.

Aged↗
PubMed1993

Using patient reports to assess health-related quality of life after total hip replacement.

Data on disease severity, co-morbidity, and process of care were obtained from the medical records of 356 patients without rheumatoid arthritis undergoing a first unilateral total hip replacement at four teaching hospitals in California and Massachusetts. Socio-demographic characteristics, functional status prior and subsequent to hospitalization, and improvement in health status were measured with a patient questionnaire 12 months after discharge. Completed questionnaires were received from 284 patients, a response rate of 79.8%. The questionnaire was acceptable to patients, reliable, and had good construct validity. The data indicate substantial benefits from hip arthroplasty. As expected, pre-surgical functioning was a strong predictor of outcomes 1 year after surgery. Controlling for pre-surgical functioning, age was not related to outcomes.

Activities of Daily Living↗
PubMed1993

Socioeconomic forces affecting medicine: times of increased retrenchment and accountability.

Costs of health care are increasing at a rapid rate, but both access to care and costs of care have become focal points for current national and local debates. Access issues relate not only to those who have no insurance but also to those who are underinsured. Cost issues relate most directly to radiology and nuclear medicine through their impact on coverage and payment. Increasing scrutiny is paid to criteria used for these purposes, and major changes at the federal and private level can be expected in the next decade. Finally, the ubiquitous development of practice guidelines and their expected use in physician profiles will influence the practice of medicine significantly in the future.

Cost Control↗