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Biomedical subjects

S Greenfield

Publications and source records attributed to S Greenfield.

At least 73 records · Page 4Linked to original sources
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

Long-term functioning and well-being outcomes associated with physical activity and exercise in patients with chronic conditions in the Medical Outcomes Study.

This study was carried out to determine whether levels of physical activity of patients with various chronic diseases are associated with subsequent functioning and well-being. It was an observational 2-year longitudinal design. The setting was offices of medical and mental health practices within health maintenance organizations, large multispecialty groups, and solo practices or small single-specialty group practices in three U.S. cities. Included in the study were 1758 adult patients with one or more of the following: diabetes, hypertension, congestive heart failure, recent myocardial infarction, depressive symptoms, or current depressive disorder. Outcome measures included physical, role, and functioning; energy/fatigue; pain intensity; sleep problems; depressed affect, anxiety, positive affect, and overall psychological distress/well-being; health distress; and current health perceptions. Cross-sectional (base-line), 2-year endpoint, and change score relationships were evaluated between baseline levels of physical activity and each outcome, controlling for chronic conditions, comorbidity, smoking, alcohol use, overweight, self-reported adherence, and other patient and study characteristics. Higher baseline levels of exercise were uniquely associated with better functioning and well-being at baseline and 2 years later for some measures. The magnitude of the differences varied by disease group, but tended to be between 0.17 and 0.39 of the baseline SD. Greater levels of exercise are associated with feeling and functioning better for patients with chronic conditions over a 2-year period, suggesting that this is a fruitful area for further study using controlled interventions.

Activities of Daily Living↗
PubMed1994

Principles and practice of case mix adjustment: applications to end-stage renal disease.

For optimal case mix adjustment, it is necessary to build risk or severity models to fit the disease and its outcome. For cardiac disease, for example, several risk models predict the outcome of mortality. These risk models include variables that, by themselves in multivariable models, predict death. If a variable is associated with death independent of treatment or quality of care, it has to be adjusted for and, therefore, included in the model. Similar models have to be developed and tested for end-stage renal disease. A complete risk model would consist of age, sex, the severity of the primary disease of interest (here, end-stage renal disease), not just the presence but also the severity of all co-morbid disease, and, finally, a measurement of functional status or quality of life. This last measurements is associated with outcome beyond and independent of the above noted severity components. These factors (or "severity" or "patient mix" dimensions) then have to be developed in relation to a specific outcome or response variable. Cholesterol and hypertension are risk factors for long-term events and mortality, but not for 2-year symptoms and quality of life. Thus, the model has to be defined by the type of outcome and by the time interval over which the variable acts. For end-stage renal disease, at least one of the major types of outcome will be quality of life. Our case mix measures for hospital co-morbidity and for office practice chronic disease are defined by and intended to predict functional status in the short run, because that is the outcome of interest for dollars spent and for most of the care rendered to patients with chronic disease before the very end stages. Creating a valid case mix or severity measurement aimed at or defined by quality of life thus involves the creation of new models, the testing of those models, the revision based on the empirical testing, and, finally, generalizing to other sites beyond which the data were collected. Useful case mix measurements will be parsimonious, feasible, reliable, validated against the outcome of interest, shown to work in diverse settings, and acceptable to users, especially clinicians.

Activities of Daily Living↗
PubMed1994

ASA Physical Status and age predict morbidity after three surgical procedures.

OBJECTIVE: American Society of Anesthesiologists-Physical Status scores (ASA-PS) and age were used to adjust for case-mix differences when evaluating surgical morbidity and resource use after total hip replacement (THR), transurethral prostatectomy (TURP), or cholecystectomy. SUMMARY BACKGROUND DATA: Variations in complication rates or resource use among patients treated for a particular primary condition should be adjusted for coexistent disease. Age and ASA-PS scores are readily available and can be useful to stratify surgical patients for risk. METHODS: One thousand ninety patients at five academic medical centers in California and Massachusetts who underwent THR, TURP, or cholecystectomy between 1985 and 1987 were studied. Data were obtained from medical records and a self-administered questionnaire to measure length of stay (LOS), postoperative complication rates, and follow-up physician visits. Data were analyzed with one- and two-way analysis of variance with the Bonferroni correction. RESULTS: Increasing age and ASA-PS scores were associated significantly with increased LOS, complication rates, and frequency of post-discharge physician office visits. No interaction effect between age and ASA-PS scores was observed. CONCLUSIONS: Age and ASA-PS scores can predict postoperative morbidity, specific for each operation studied. Assessment of co-morbidity in surgical patients can be accomplished easily and with minimal expense. While remaining budget neutral, the distribution of reimbursements should be based on those preoperative risk factors that predict longer LOS and higher complication rates.

Adult↗
PubMed1994

Preventive eye care in people with diabetes is cost-saving to the federal government. Implications for health-care reform.

OBJECTIVE: Diabetic retinopathy, which leads to macular edema and retinal neovascularization, is the leading cause of blindness among working-age Americans. Previous research has demonstrated significant cost savings associated with detection of eye disease in Americans with type I diabetes. However, detection and treatment of eye disease among those with type II diabetes was previously thought not to be cost-saving. Our purpose was to estimate the current and potential federal savings resulting from the screening and treatment of retinopathy in patients with type II diabetes, based on recently available data concerning efficacy of treating both macular edema and neovascularization along with new data on federal budgetary costs of blindness. RESEARCH DESIGN AND METHODS: We used computer modeling, incorporating data from population-based epidemiological studies and multicenter clinical trials. Monte Carlo simulation was used, combined with sensitivity analysis and present value analysis of cost savings. RESULTS: Screening and treatment for eye disease in patients with type II diabetes generates annual savings of $247.9 million to the federal budget and 53,986 person-years of sight, even at current suboptimal (60%) levels of care. If all patients with type II diabetes receive recommended care, the predicted net savings (discounted at 5%) exceeds $472.1 million and 94,304 person-years of sight. Nearly all savings are associated with detection and treatment of diabetic macular edema. Enrolling each additional person with type II diabetes into currently recommended ophthalmological care results in an average net savings of $975/person, even if all costs of care are borne by the federal government. CONCLUSIONS: Our analysis indicates that prevention programs aimed at improving eye care for patients with diabetes not only reduce needless vision loss but also will provide a financial return on the investment of public funds.

Blindness↗
PubMed1994

The uses of outcomes research for medical effectiveness, quality of care, and reimbursement in type II diabetes.

Randomized controlled trials (RCTs), such as the Diabetes Control and Complications Trial (DCCT), usually evaluate the efficacy of a single treatment strategy. The DCCT, for example, evaluates intensive diabetes management aimed at achieving glucose levels as close to normal as possible to modify specific pathophysiological outcomes--specifically, the development or worsening of microvascular disease. In contrast, longitudinal observational studies, such as the type II diabetes Patient Outcome Research Team (PORT) study, address medical effectiveness; that is, how well prevailing treatments work in clinical practice settings. The PORT relies heavily on patient-reported measures of general and diabetes-specific health status, in addition to using complications as major study outcomes. In the type II diabetes PORT, 4,000 patients with type II diabetes and a wide range of socioeconomic, demographic, and disease characteristics, from three widely dispersed geographic settings and varying systems of care, are being followed for a 2.5-year period. Data are collected from periodic self-administered patient questionnaires and from administrative data bases. In the PORT study, nonmutable confounders, such as case-mix, and potentially mutable features, such as patients' preferences for treatment, health habits, regimen adherence, family support, and physician's interpersonal style, are carefully measured. The PORT study will examine the effectiveness of preventive care and established disease treatment in relation to eye, cardiovascular, and extremity disease, measuring and relating use of health-care services to patient outcomes. The results have the potential for maximizing quality of care and minimizing use of services in type II diabetes by matching physician-level profiles of patient outcomes with medical-care-process data and making this information accessible to practicing physicians.

Clinical Trials as Topic↗
PubMed1993

Recall of recommendations and adherence to advice among patients with chronic medical conditions.

BACKGROUND: Patient adherence to treatment regimens may be a critical mediator between physician recommendations and patient outcomes, but levels of adherence have not been compared across disease groups, and patient self-reports have not been well validated. METHODS: To determine recall of and adherence to physicians' recommendations among patients with chronic medical conditions and to measure the correspondence between self-reported adherence and disease activity, we analyzed data from the Medical Outcomes Study. A total of 1751 patients with diabetes mellitus, hypertension, and heart disease were identified among 20,223 patients visiting family physicians, general internists, cardiologists, and endocrinologists in 1986. Main outcome measures included recall of 15 disease-specific recommendations, self-reported general and specific adherence, and correlations between adherence and clinical measures of disease activity and control. RESULTS: Among patients in all three disease groups, the proportion recalling recommendations to take prescribed medications (> or = 90%) exceeded the fraction recalling recommendations to follow a restricted diet, exercise regularly, and perform various self-care activities (22% to 84%). Adherence to recalled recommendations was similar across conditions but varied markedly according to the nature of the recommendations; for example, 91% of diabetics took prescribed medications but 69% followed a diabetics diet and 19% engaged in regular exercise. Adherence to recommendations was correlated with reduced serum glucose (r = -.33) and glycohemoglobin (r = -.25) levels among insulin-dependent diabetics and with reduced diastolic blood pressure among patients with hypertension (r = -.15). CONCLUSIONS: The majority of chronically ill patients failed to recall elements of potentially important medical advice and did not always adhere to advice that was recalled. Self-reported adherence was correlated with clinical measures of disease activity and control. Additional research is needed not only to improve adherence to medical advice in patients with chronic illnesses but also to determine which life-style changes are truly beneficial for these patients.

Adult↗
PubMed1993

Differential cholinergic and non-cholinergic actions of acetylcholinesterase in the substantia nigra revealed by fasciculin-induced inhibition.

The effects of the peptide fasciculin (FAS), a potent inhibitor of acetylcholinesterase (AChE) have been examined, following unilateral microinfusion, on tissue levels of monoamines in the rat substantia nigra and concomitant circling behaviour. Although FAS inhibited 87% of total AChE, the levels of dopamine and its metabolites remained unchanged. Furthermore, the treatment induced modest contraversive rotation which was markedly enhanced in the presence of a systemic challenge with apomorphine. This behavioural effect of FAS was partially reversed by systemically administered atropine. Any possible interaction of FAS with nigral dopamine systems was further investigated by testing the peptide in animals that five days earlier had undergone a 6-hydroxydopamine (6-OHDA) lesion of the SN such that dopamine and AChE were significantly but not completely reduced. In a majority of these animals, FAS treatment caused a reversal of the lesion induced ipsiversive rotation, ie restored contraversive rotation. It is concluded that in the SN, FAS can have biochemical and behavioural actions independent of local dopamine systems and linked to cholinergic transmission. In addition, treatment with FAS in the substantia nigra also reveals the possible existence of at least two distinct pools of AChE with, respectively, non-cholinergic and cholinergic actions.

3,4-Dihydroxyphenylacetic Acid↗
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

The importance of co-existent disease in the occurrence of postoperative complications and one-year recovery in patients undergoing total hip replacement. Comorbidity and outcomes after hip replacement.

Co-existent or comorbid diseases are appreciated as prognostic factors in studies of quality and effectiveness of care when mortality is the end point. The need to measure and adjust for comorbidity in studies of postoperative hospital complications or long-term recovery from surgery has not been documented. In this study, we determined the impact of co-existent disease on post-operative complications and 1-year health-related quality of life in patients hospitalized for a total hip replacement. The study population consisted of a cohort of 356 patients who were hospitalized in four teaching hospitals in California and Massachusetts for a total hip replacement. Patients' medical records were reviewed to collect information regarding severity of illness, co-existent disease, and postoperative complications. The kind and amount of baseline preoperative co-existent disease was measured from medical record information at admission using a four level Index of co-existent Disease (ICED). Approximately 12 months after hospital discharge, 283 (80%) of the patients were surveyed by questionnaire. The presence and amount of co-existent disease were significant predictors of postoperative complications. The complication rates ranged from 3% to 41% between the lowest and highest levels of the ICED. Patients treated at the four study hospitals differed in functional outcomes 1 year after surgery. Functional outcomes were strongly related to ICED scores: patients in Level 4 ICED scored 26.8 points lower in instrumental activities of daily living than patients in Level 1. After controlling for gender, age, education, and marital status, ICED remained a significant predictor of functional status at 1 year. Furthermore, differences among hospitals in functional outcomes disappeared when the ICED was included in the model to adjust for patient characteristics at the time of surgery. A measure of co-existent disease was crucial in explaining differences among hospitals in recovery from total hip replacement patients.

Activities of Daily Living↗
PubMed1992

Differential actions of acetylcholinesterase on the soma and dendrites of dopaminergic substantia nigra neurons in vitro.

In the substantia nigra, acetylcholinesterase (AChE) has non-cholinergic action on dopaminergic neurons. The subset of neurons particularly sensitive to AChE are characterized by functionally active apical dendrites extending into the pars reticulata and generating a powerful calcium conductance. This study thus attempted to establish directly the importance of these dendrites regarding the action of AChE. Segregation of the pars compacta from the pars reticulata did not affect the AChE-induced hyperpolarization on this sub-set of dopaminergic neurons. However, the ionic basis of the hyperpolarization was related to the integrity of the neurons: AChE caused an opening of potassium channels in intact cells. On the other hand when the pars reticulata containing apical dendrites was removed, an action of AChE involving the closure of calcium/sodium channels was revealed. The results demonstrate that the net effect of AChE need not be related to any particular segment of the dopaminergic neurons, whereas the nature of the mechanism underlying that effect depends on the presence, or otherwise, of the apical dendrites.

Acetylcholinesterase↗
PubMed1992

Differences in the mix of patients among medical specialties and systems of care. Results from the medical outcomes study.

OBJECTIVE: To determine differences in the mix of patients among medical specialties and among organizational systems of care. STUDY DESIGN: Cross-sectional analysis of 20,158 adults (greater than or equal to 18 years of age) who visited providers' offices during 9-day screening periods in 1986. Patient and physician information was obtained by self-administered, standardized questionnaires. SETTING: Offices of 349 physicians practicing family medicine, internal medicine, endocrinology, and cardiology within health maintenance organizations, large multispecialty groups, and solo or small single-specialty group practices in three major US cities. OUTCOME MEASURES: Demographic characteristics, prevalence of chronic disease, disease-specific severity of illness, and functional status and well-being. RESULTS: Among patients with selected physician-reported chronic illnesses (diabetes, hypertension, recent myocardial infarction, or congestive heart failure), increasing levels of severity were associated with decreasing levels of functional status and well-being and with increased hospitalizations, more physician visits, and higher numbers of prescription drugs. Compared with patients of general internists, patients of cardiologists were older (56 vs 47 years, P less than .01), had worse functional status and well-being scores (P less than .01), and carried more chronic diagnoses (mean 1.32 vs 1.02, P less than .01); patients of family practitioners were younger (40 vs 47 years, P less than .01) and more functional (P less than .01), carried fewer chronic diagnoses (0.70 vs 1.02, P less than .01), and (among diabetic patients only) had lower disease-specific severity scores (2.06 vs 2.30 on a five-point scale, P less than .01). Compared with patients in health maintenance organizations, patients visiting solo practitioners under fee-for-service payment were older (50 vs 45 years, P less than .01) and sicker (had worse physical functioning) and had a higher mean number of chronic diagnoses (1.10 vs 0.93, P less than .01). CONCLUSION: Patient mix is related to utilization and differs significantly across medical specialties and systems of care. These differences must be taken into account when interpreting variations in utilization and outcomes across specialties and systems, and when considering alternative policies for payment.

Activities of Daily Living↗
PubMed1992

Variations in resource utilization among medical specialties and systems of care. Results from the medical outcomes study.

OBJECTIVE: To examine whether specialty and system of care exert independent effects on resource utilization. STUDY DESIGN: Cross-sectional analysis of just over 20,000 patients (greater than or equal to 18 years of age) who visited providers' offices during 9-day periods in 1986. Patient- and physician-provided information was obtained by self-administered questionnaires. SETTING: Offices of 349 physicians practicing family medicine, internal medicine, endocrinology, and cardiology within health maintenance organizations, large multispecialty groups, and solo practices or small single-specialty group practices in three major US cities. OUTCOME MEASURES: Indicators of the intensity of resource utilization were examined among four medical specialties (family practice, general internal medicine, cardiology, and endocrinology) and five systems of care (health maintenance organization, multispecialty group-fee-for-service, multispecialty group-prepaid; solo practice and single-specialty group-fee-for-service, and solo practice and single-specialty group-prepaid) before and after controlling for the mix of patients seen in these offices. The indicators of resource utilization were hospitalizations, annual office visits, prescription drugs, and common tests and procedures, with rates estimated on both a per-visit and per-year basis. RESULTS: Variation in patient mix was a major determinant of the large variations in resource use. However, increased utilization was also independently related to specialty (cardiology and endocrinology), fee-for-service payment plan, and solo and single-specialty group practice arrangements. After adjusting for patient mix, solo practice/single-specialty groups-fee-for-service had 41% more hospitalizations than health maintenance organizations. General internists had utilization rates somewhat greater than family physicians on some indicators. CONCLUSION: Although variations in patient mix should be a major determinant of variations in resource use, the independent effects of specialty training, payment system, and practice organization on utilization rates need further explication. The 2- and 4-year outcomes now being analyzed will provide information critical to interpretation of the variations reported herein.

Adult↗
PubMed1992

Reactive fibromyalgia syndrome.

OBJECTIVE: To determine the frequency of a precipitating event occurring prior to the onset of fibromyalgia syndrome, in a consecutive series of patients. Outcome in patients in whom there was a causative factor was compared with that in patients with primary fibromyalgia. METHODS: Records of patients presenting over a 4-year period who fulfilled criteria for fibromyalgia were reviewed, and patients were classified as having reactive fibromyalgia if a specific event prior to the onset of illness could be identified. Outcome features, including employment status and disability compensation, were compared in patients with reactive fibromyalgia versus those with primary fibromyalgia. RESULTS: Twenty-nine of 127 patients (23%) with a primary rheumatologic diagnosis of fibromyalgia reported having trauma, surgery, or a medical illness before the onset of fibromyalgia, and were classified as having reactive fibromyalgia. Patients in this group were more disabled than those with primary fibromyalgia, resulting in loss of employment in 70%, disability compensation in 34%, and reduced physical activity in 45%. CONCLUSION: The development of fibromyalgia after a precipitating event may represent the onset of a prolonged and disabling pain syndrome with considerable social and economic implications.

Employment↗
PubMed1992

Ambulatory testing for capitation and fee-for-service patients in the same practice setting: relationship to outcomes.

Previous studies of the impact of varying reimbursement incentives on physician behavior have not explored the simultaneous implications for patients' health outcomes. Using a single group of physicians who provided care for hypertensive patients with either capitation (N = 99) or fee-for-service (N = 66) health insurance plans, physicians' test-ordering behavior and patients' subsequent health outcomes were examined. After controlling for patients' age, severity of hypertension, and level of comorbidity, it was found that patients with capitation health insurance had fewer laboratory tests and lower overall charges than the fee-for-service patients, with no clinical or statistically significant differences in 1-year health outcomes, specifically blood pressure control. The study concludes that capitation can result in reduction in charges associated with management of hypertension, without apparent compromise in proximate health outcomes.

Adult↗
PubMed1992

Recent developments and future issues in the use of health status assessment measures in clinical settings.

This paper provides a broad overview of the assessment of health status in clinical practice in three parts. Yesterday: The nation has undergone a paradigm shift in health-related thinking. The former paradigm emphasized only disease; the new emphasizes health, functioning, well-being, and disease. Measures of health and disease have evolved to reflect the new paradigm. Many are designed for clinical settings, based on measurement science, and are relatively brief. These newer measures have been used to document the natural history of disease, evaluate treatment effectiveness, and improve clinical case management. Today: Two barriers block full-scale use in clinical settings. The first barrier involves the meaning and interpretation of health status scores. Patients' scores are influenced by several types of patient mix variables and the timing of measurements. Interpretation is enhanced by valid normative data displaying the variability in health status among homogenous patient groups. The second barrier is utilization and mainstreaming. It involves all of the issues associated with changing the day-to-day behavior of clinicians and providers' routine processes to facilitate routine use of health status measures in clinical settings. Tomorrow: In the next decade, the nation will attempt to overhaul the health care system. As it does so, it will struggle with many issues: 1) clarifying the true aim of health care; 2) standardizing measures of health across patients, providers, and settings to evaluate benefit; 3) establishing cause and effect among structural-input factors, care delivery processes, and health outcomes valued by society; and 4) determining if and when cost containment actions have adverse effects on health outcomes. In this context, the importance of interpreting change in health status has a central role.

Activities of Daily Living↗