Educating physicians prepared to improve care and safety is no accident: it requires a systematic approach

While most newly qualified physicians are well prepared in the science base of medicine and in the skills that enable them to look after individual patients, few have the skills necessary to improve care and patient safety continuously. We apply a systems analysis from the field of human error to identify ways in which medical school education can increase the number of graduates prepared to reflect on and improve professional practice. Doing so requires a systematic approach involving entrance requirements, the curriculum, the organizational culture of training environments, student assessment, and program evaluation.

Gone but not forgotten: the search for the lost surgical specimens: application of quality improvement techniques in reducing medical error

A lost surgical specimen prompted an investigation of both the human processes and the systemic factors involved in surgical specimen handling regarding how health care organizations approach medical error prevention and patient safety promotion. Quality improvement techniques and the conceptual error model of James Reasons were employed to understand the interaction between the local process of specimen handling and the systemic influences to medical error management. Error management recognizes the inevitability of both individual and systemic error. Through the use of quality improvement techniques and models of error analysis, health care organizations can investigate the error potential of health care delivery and address the human and organizational interaction necessary to improve patient safety and manage medical error.

Risk adjusting cesarean delivery rates: a comparison of hospital profiles based on medical record and birth certificate data

OBJECTIVES

Compare the discrimination of risk-adjustment models for primary cesarean delivery derived from medical record data and birth certificate data and determine if the two types of models yield similar hospital profiles of risk-adjusted cesarean delivery rates.

DATA SOURCES/STUDY SETTING

The study involved 29,234 women without prior cesarean delivery admitted for labor and delivery in 1993-95 to 20 hospitals in northeast Ohio for whom data abstracted from patient medical records and data from birth certificates could be linked.

STUDY DESIGN

Three pairs of multivariate models of the risk of cesarean delivery were developed using (1) the full complement of variables in medical records or birth certificates; (2) variables that were common to the two sources; and (3) variables for which agreement between the two data sources was high. Using each of the six models, predicted rates of cesarean delivery were determined for each hospital. Hospitals were classified as outliers if observed and predicted rates of cesarean delivery differed (p < .05).

PRINCIPAL FINDINGS

Discrimination of the full medical record and birth certificate models was higher (p < .001) than the discrimination of the more limited common and reliable variable models. Based on the full medical record model, six hospitals were classified as statistical (p < .01) outliers (three high and three low). In contrast, the full birth certificate model identified five low and four high outliers, and classifications differed for seven of the 20 hospitals. Even so, the correlation between adjusted hospital rates was substantial (r = .71). Interestingly, correlations between the full medical record model and the more limited common (r = .84) and reliable (r = .88) variable birth certificate models were higher, and differences in classification of hospital outlier status were fewer.

CONCLUSION

Birth certificates can be used to develop cesarean delivery risk-adjustment models that have excellent discrimination. However, using the full complement of birth certificate variables may lead to biased hospital comparisons. In contrast, limiting models to data elements with known reliability may yield rankings that are more similar to rankings based on medical record data.

The adrenal incidentaloma: disease of modern technology and public health problem

The optimal strategy for evaluation of a patient with an incidentally discovered adrenal mass is unclear and remains controversial. A prospective multi-center randomized (or even non-randomized) trial would go a long way toward resolving the controversies. However, we lack such a study. Review of the literature supports the view that such patients are at somewhat increased risk of morbidity and mortality and this implies a benefit of early diagnosis for at least for some of the disorders. Our ability to accurately determine clinically those at increased risk among the vast majority who are not at increased risk is poor. We therefore rely on biochemical and radiological diagnostic tests, which have their own limitations. Subjecting patients to unnecessary testing and treatment carries its own set of risks. The diagnostic process itself may contribute considerable anxiety, expense, and if invasive cause pain and other morbidity. The harm that occurs as false positive results are pursued has been termed the "cascade effect" [34]. We must avoid the pitfalls of overestimation of disease prevalence and of the benefits of therapy resulting from advances in diagnostic imaging. In the meantime, we must use our best clinical judgement based upon the best available evidence to ensure that we maximize the benefit to those patients with AI who have clinically significant adrenal disorders and minimize the harm to those who do not.

Using an Improvement Model to Reduce Adverse Drug Events in VA Facilities

BACKGROUND

Adverse drug events cause significant morbidity and mortality in health care. Many adverse drug events are due to medication errors and are preventable. In 1999 and 2000 the Patient Safety Center of Inquiry collaborated with the Institute for Healthcare Improvement (IHI) to implement a quality improvement (QI) project designed to reduce medication errors within the Veterans Administration system.

METHODS

During a 6- to 9-month period, interdisciplinary teams that want to achieve much higher levels of performance work on a common aim, under the guidance of faculty, and come together for three 2-day educational and planning sessions. Between these sessions, teams implement some of the suggested changes, measure the results of those changes, and report back to the larger group.

RESULTS

During the formal project, teams collected allergy information on more than 20,000 veterans and averted 1,833 medication errors that had the potential to cause adverse events. At 6-month follow-up, the majority of teams remained intact, continued to collect data, and maintained their gains, approximately doubling the results obtained during the formal project. Half of the teams expanded their efforts to other settings, and one-third of the teams expanded beyond their original topics. Returns on investment in the QI effort were substantial.

CONCLUSIONS

The results suggest that gains made in organized QI efforts can be maintained for 6 months without additional external support or coaching if team structure and leadership support remain intact. Facilitators of QI efforts should focus on teams that are having difficulty learning new techniques. Finally, this effort appeared to generate cost savings.

Using severity-adjusted mortality to compare performance in a Veterans Affairs hospital and in private-sector hospitals

The objective of this study was to compare hospital mortality in Veterans Affairs (VA) and private-sector patients. The study included 5016 patients admitted to 1 VA hospital. Admission severity of illness was measured using a commercial methodology that was developed in a nationwide database of 850,000 patients from 111 private-sector hospitals. The method uses data abstracted from patients' medical records to predict the risk of death in individual patients, based on the normative database. Analyses compared actual and predicted mortality rates in VA patients. VA patients had higher (P < .05) severity of illness than private-sector patients. The observed mortality rate in VA patients was 4.0% and was similar (P = .09) to the predicted risk of death (4.4%; 95% confidence interval 4.0-4.9%). In subgroup analyses, actual and predicted mortality rates were similar in medical and surgical patients and in groups stratified according to severity of illness, except in the highest severity stratum, in which actual mortality was lower than predicted mortality (57% vs 73%; P < .001). We found that in-hospital mortality in 1 VA hospital and a nationwide sample of private-sector hospitals were similar, after adjusting for severity of illness. Although not directly generalizable to other VA hospitals, our findings nonetheless suggest that the quality of VA and private-sector care may be similar with respect to one important and widely used measure.

The diagnostic dilemma of incidentalomas. Working through uncertainty

The clinical evaluation of incidentally found nodules in the adrenal, thyroid, and pituitary glands is a challenge for physicians, regardless of their level of expertise. Choosing the most direct and cost-effective diagnostic approach and deciding when to treat or not to treat are common dilemmas in clinical practice. This article outlines one diagnostic approach using medical decision-making techniques such as heuristic thinking, critical appraisal of the literature, treatment threshold probability assessment, Bayes' theorem, and discriminant properties of diagnostic tests. These skills are usually discussed in postgraduate training curricula. Nevertheless, they often seem foreign to many clinicians. Evidence suggests that training in these techniques can improve clinical decision making. Use of the skills outlined herein provides a framework to work through the diagnostic uncertainty common in the evaluation of incidentalomas. This approach does not provide perfect answers, as noted in examplar 3 in which two experts argued about the actual pretest probability and treatment thresholds for pituitary incidentalomas. Even if there were no such disagreement, each patient presents unique issues, and there will always be some uncertainty. Nevertheless, this approach provides a starting point from which critical decisions can be made for individual patients.

Pituitary incidentalomas

The optimal strategy for hormonal screening of a patient with any incidentally discovered pituitary mass is unknown. The authors' review of the endocrinologic literature supports the view that such patients are at slightly increased risk for morbidity and mortality. This risk implies a benefit of early diagnosis for at least for some of the disorders, suggesting the importance of case finding. Nevertheless, the data in Table 1 illustrate that clinically diagnosed hormone-secreting pituitary tumors are far less common than incidentalomas. Clinically, one cannot accurately determine the approximately 0.5% of patients with incidentaloma who are at increased risk among the vast majority who are not. Given the limitations of diagnostic tests, effective hormonal screening requires a sufficiently high pretest probability to limit the number of false-positive results. This condition is met to varying degrees in the patient with a small incidentally discovered pituitary mass but no signs or symptoms of hormone excess. Even the more common lesions, such as prolactinoma, are relatively rare. [table: see text] Subjecting patients to unnecessary testing and treatment is associated with risk. In addition to its initial cost, testing may result in further expense and harm as false-positive results are pursued, producing the "cascade effect" described by Mold and Stein as a "chain of events (which) tends to proceed with increasing momentum, so that the further it progresses the more difficult it is to stop." The extensive evaluations performed for some patients with incidentally discovered masses may reflect the unwillingness of many physicians to accept uncertainty, even in the case of an extremely unlikely diagnosis. This unwillingness may be driven, in part, by fear of potential malpractice liability, the failure to appreciate the influence of prevalence data on the interpretation of diagnostic testing, or other factors. The major justification for further evaluation of these patients is not so much to avoid morbidity and mortality for the rare patient who truly is at increased risk but to reassure patients in whom further testing is negative and the physician. Physicians must take care not to create inappropriate anxiety in patients by overemphasizing the importance of an incidental finding unless it is associated with a realistic clinical risk. The authors' recommendations are based on currently available information to minimize the untoward effects of the cascade. As evidence accumulates, these recommendations may need to be revised. The benefit of the diagnosis of an adrenal or pituitary disorder must be considered in the context of the patient's overall condition. Additional studies are needed to analyze the clinical utility of hormonal screening for these common radiologic findings. Data from these studies can be used to identify critical gaps in knowledge and to adopt the epidemiologic methods of evaluation of evidence that have been applied to preventive measures. One must be careful to recognize lead-time bias, in which survival can appear to be lengthened when screening simply advances the time of diagnosis, lengthening the period of time between diagnosis and death without any true prolongation of life; and length bias, which refers to the tendency of screening to detect a disproportionate number of cases of slowly progressive disease and to miss aggressive cases that, by virtue of rapid progression, are present in the population only briefly. Physicians must avoid the pitfalls of overestimation of disease prevalence and of the benefits of therapy resulting from advances in diagnostic imaging. Clinical judgment based on the best available evidence should be complemented and not replaced by laboratory data.

Sexual function in men with diabetes type 2: association with glycemic control

PURPOSE

We evaluated the association of glycemic control with erectile dysfunction in men with diabetes type 2.

MATERIALS AND METHODS

A convenience sample of men with diabetes type 2 at the Cleveland Veterans Affairs Medical Center completed questions 1 to 5 of the International Index of Erectile Function. The primary outcome measure was erectile function score, calculated as the sum of questions 1 to 5. Details of disease duration, complications, medication use, patient age and level of glycosylated hemoglobin were obtained by reviewing the medical record.

RESULTS

Mean subject age plus or minus standard deviation was 62.0+/-12.3 years, mean hemoglobin A1c was 8.1%+/-1.9% and mean erectile function score was 16.6+/-5.9 (range 5 to 23). Stratified analysis revealed that mean erectile function score decreased as hemoglobin A1c increased (analysis of variance p = 0.002). The test for linearity was also significant (p = 0.001). There were no statistically significant associations of levels of glycemic control with alpha-blocker, beta-blocker or diuretic use. Bivariate analysis showed a significant correlation of hemoglobin A1c with neuropathy but not with patient age, duration of diabetes, alpha-blockers, beta-blockers or diuretics. Multivariate analysis demonstrated that hemoglobin A1c was an independent predictor of erectile function score (p<0.001) even after adjusting for peripheral neuropathy, which was also an independent predictor (p = 0.023).

CONCLUSIONS

Our data add to the growing body of literature suggesting that erectile dysfunction correlates with the level of glycemic control. Peripheral neuropathy and hemoglobin A1c but not patient age were independent predictors of erectile dysfunction.

Management of pituitary incidentalomas. A survey of British and American endocrinologists

The results of a survey of endocrinologists concerning their approaches to the evaluation of a patient with an incidentally discovered pituitary mass are presented in this article. The practices of British and American endocrinologists are compared. The wide variation in diagnostic approaches to the practice of ordering tests in the United Kingdom and the United States highlights the need for research and debate regarding the most appropriate management of patients with such findings.

Variations in risk-adjusted cesarean delivery rates according to race and health insurance

OBJECTIVE

To assess the association between race and insurance and Cesarean delivery rates after adjusting for clinical risk factors that increase the likelihood of cesarean delivery.

DESIGN

Retrospective cohort study in 21 hospitals in northeast Ohio.

SUBJECTS

25,697 women without prior cesarean deliveries admitted for labor and delivery January 1993 through June 1995.

METHODS

Demographic and clinical data were abstracted from patients' medical records. The risk of cesarean delivery was adjusted for 39 maternal and neonatal risk factors that were included in a previously developed risk-adjustment model using nested logistic regression analysis.

MAIN OUTCOME MEASURES

Odds ratios for cesarean delivery in nonwhite patients relative to whites and for patients with government insurance or who were uninsured relative to patients with commercial insurance.

RESULTS

The overall rate of cesarean delivery was similar in white and nonwhite patients (15.8% and 16.1%, respectively), but rates varied (P < 0.001) according to insurance (17.0%, 14.2%, 10.7% in patients with commercial insurance, government insurance, and without insurance, respectively). However, after adjusting for clinical factors, the adjusted odds ratio (OR) of cesarean delivery was higher in nonwhite patients (OR = 1.34; 95% CI: 1.14-1.57; P < 0.001), but similar for patients with government insurance (OR = 1.01; 95% CI: 0.90-1.14; P = 0.84) and lower for uninsured patients (OR = 0.65; 95% CI, 0.41, 1.03; P = 0.067), albeit not statistically significant. In analyses stratified according to quintiles of predicted risk of cesarean delivery, racial differences were largely limited to patients in the lower risk quintiles. However, differences in odds ratios for uninsured patients were seen across the risk quintiles, although odds ratios were not statistically significant.

CONCLUSION

After adjusting for clinical factors, race and insurance status may independently influence the use of cesarean delivery. The higher rates in nonwhites and lower rates in the uninsured may reflect differences in patient preferences or expectations, differences in physician practice, or unmeasured risk factors. The lower odds of cesarean delivery in uninsured women, particularly women at high risk, may raise the issue of underutilization of services and warrants further study.

Attitudes of faculty, housestaff, and medical students toward clinical practice guidelines

PURPOSE

To examine attitudes of faculty, housestaff, and medical students toward clinical practice guidelines.

METHOD

In a 1997 cross-sectional survey, a two-part, 26-item, self-administered questionnaire was mailed to all faculty, housestaff, and medical students in the department of internal medicine at Case Western Reserve University School of Medicine. The questionnaire asked for demographic information and attitudes toward clinical guidelines.

RESULTS

Of 379 persons surveyed, 254 (67%) returned usable questionnaires: 56% of the medical students, 70% of the housestaff, and 73% of the full-time faculty. Medical students reported learning about guidelines predominantly during clerkships in internal medicine (71%) and pediatrics (68%). Overall, the respondents agreed most strongly that guidelines are "useful for the care of common problems," and least strongly that guidelines are "difficult to apply to individual patients" and "reduce physician options in patient care." Faculty were more likely to consider guidelines a "good educational tool" and less likely than were medical students and housestaff to agree that they promote "cookbook medicine." Of 11 influences on clinical decision making, the three groups together rated practice guidelines eighth or ninth. The use of guidelines for academic investigations was rated most appropriate, overall. In terms of their appropriateness, faculty consistently rated the use of guidelines more favorably except for use in malpractice suits.

CONCLUSION

Faculty, housestaff, and medical students have significantly different perceptions of and attitudes toward clinical practice guidelines. Further studies are needed to explain the reasons for these differences. Considerable education and involvement must occur at all levels for practice guidelines to be successfully implemented and understood.

Impact of risk-adjusting cesarean delivery rates when reporting hospital performance

CONTEXT

Hospitals and health plans are often ranked on rates of cesarean delivery, under the assumption that lower rates reflect more appropriate, more efficient care. However, most rankings do not account for patient factors that affect the likelihood of cesarean delivery.

OBJECTIVE

To compare hospital cesarean delivery rates before and after adjusting for clinical risk factors that increase the likelihood of cesarean delivery.

DESIGN

Retrospective cohort study.

SETTING

Twenty-one hospitals in northeast Ohio.

PATIENTS

A total of 26127 women without prior cesarean deliveries admitted for labor and delivery from January 1993 through June 1995.

MAIN OUTCOME MEASURES

Hospital rankings based on observed and risk-adjusted cesarean delivery rates.

RESULTS

The overall cesarean delivery rate was 15.9% and varied (P<.001) from 6.3% to 26.5% in individual hospitals. Adjusted rates varied from 8.4% to 22.0%. The correlation between unadjusted and adjusted hospital rankings (ie, 1-21) was only modest (R=0.35, P=.12). Whereas 7 hospitals were classified as outliers (ie, had rates higher or lower [P<.05] than overall rate) on the basis of both unadjusted and adjusted rates, outlier status changed for 5 hospitals (24%), including 2 that changed from outliers to nonoutliers, 2 that changed from nonoutliers to outliers, and 1 that changed from a high outlier to a low outlier.

CONCLUSIONS

Cesarean delivery rates varied across hospitals in a single metropolitan region. However, rankings that fail to account for clinical factors that increase the risk of cesarean delivery may be methodologically biased and misleading to the public.

Management of incidental pituitary microadenomas: a cost-effectiveness analysis

The objective of this study was to compare the cost-effectiveness of four management strategies for a patient with an incidentally discovered asymptomatic pituitary microadenoma. A decision analytic Markov model was used to determine the incremental cost-effectiveness of four clinical management strategies: 1) expectant management, 2) PRL screening, 3) an endocrine screening panel (PRL, insulin-like growth factor I, and 1-mg dexamethasone suppression test), and 4) magnetic resonance imaging (MRI) follow-up. The model incorporated the natural history of incidental microadenomas, test characteristics, pharmacological and surgical treatment outcomes, patient's quality of life, discounting, and the costs of hormone testing, bromocriptine, MRIs, hospitalization for surgery, and physician services. PRL screening, endocrine screening panel, and MRI follow-up all provided slightly greater quality-adjusted survival than expectant management, but the costs increased disproportionately more than the benefits. The incremental cost per quality-adjusted life year for PRL screening is $1,428, and that for the endocrine screening panel is $69,495. These results are most sensitive to patient anxiety about the microadenoma; increased anxiety shifts the recommended strategy to the endocrine screening panel. We conclude that in patients with an incidental asymptomatic pituitary microadenoma, a single PRL test may be the most cost-effective management strategy.

Incidental pituitary macroadenoma: a population-based study

Epidemiologic analysis of incidental macroadenoma is limited to autopsy studies and case series. There are no published data about prevalence of incidental pituitary macroadenoma in living patients. The objective of this study was to determine the prevalence of incidental pituitary macroadenoma. It was designed as an observational study of cranial computed tomography reports. An urban department of veterans affairs medical center was used for the setting. The subject group consisted of 3,550 consecutive patients at the Cleveland Department of Veterans Affairs Medical Center from January 1993 to January 1996. Patients with known or suspected pituitary or parasellar disease were excluded. Cranial computed tomography reports were reviewed. Original films and medical charts of all patients with pituitary macroadenoma were reviewed. Seven patients with incidentally discovered pituitary macroadenoma that ranged from 1 cm to 2.5 cm were found; prevalence was 0.20% (95% confidence interval 0.05, 0.35%). Evidence of partial hypopituitarism was found in most patients. All patients had normal visual fields at initial examination despite the size of the tumor, but 1 of 4 had a field cut demonstrated by Goldmann perimetry. These data confirm that, although the prevalence of incidental pituitary macroadenoma is low, screening identified patients to detect deficiency of corticotropin, thyroid-stimulating hormone, and gonadotropins and to detect visual field defects is important.

Effectiveness versus efficacy: the limited value in clinical practice of high dose dexamethasone suppression testing in the differential diagnosis of adrenocorticotropin-dependent Cushing's syndrome

High dose dexamethasone suppression testing has been widely employed in the differentiation between pituitary ACTH-dependent hypercortisolism [Cushing's disease (CD)] and the ectopic ACTH syndrome. We hypothesized that the high dose dexamethasone suppression test as it is performed in practice does not improve the ability to differentiate between these two types of ACTH-dependent Cushing's syndrome. Cases were drawn from 112 consecutive patients with ACTH-dependent Cushing's syndrome, who were then classified based upon results of inferior petrosal sinus sampling for ACTH levels. Analysis of test characteristics of high dose dexamethasone suppression testing was performed in the 73 patients for whom results are available. Statistical modeling was performed using the 68 cases with complete data on all assessed variables. Logistic regression models were used to predict the probability of pituitary-dependent Cushing's syndrome (CD) given the results of high dose dexamethasone suppression testing before and after adjustment for the contribution of a series of potential covariates. Of the 112 patients with ACTH-dependent Cushing's syndrome, 15.2% had the ectopic ACTH syndrome, and the remainder had pituitary-dependent Cushing's syndrome (CD). Patients with the ectopic ACTH syndrome were significantly older (mean, 51.9 vs. 40.2), were more likely to be male (58.8% vs. 27.4%), had shorter duration of clinical findings (mean, 11.6 vs. 39.9 months), were more likely to have hypokalemia (50% vs. 8.6%), had higher baseline 24-h urinary free cortisol [mean, 8317 vs. 1164 nmol/day (3015 vs. 422 microg)] and plasma ACTH levels [mean, 47 vs. 17 pmol/L (210 vs. 78 pg/mL)] and were less likely to suppress urinary free cortisol or plasma cortisol with high dose dexamethasone using the standard criterion of 50% or more suppression compared with patients with pituitary-dependent Cushing's syndrome. Based upon the standard criterion, the sensitivity and specificity of the high dose dexamethasone suppression test for the diagnosis of pituitary-dependent Cushing's syndrome were 81.0% and 66.7%, respectively. Although the mean percent suppression was significantly greater for patients with CD than for those with the ectopic ACTH syndrome (72.2% vs. 41.3%), the range of suppression was 0-99% for each diagnosis. The area under the receiver operating characteristic curve was 0.710 (95% confidence interval, 0.541-0.879). Logistic regression models were used to evaluate the probability of CD given the responsiveness to high dose dexamethasone suppression testing before and after adjustment for the potential contributions of other factors. A model including all of the variables (age, sex, duration, presence of hypokalemia, urinary free cortisol, and plasma ACTH) had a diagnostic accuracy of 92.7%. A model including all of these variables plus a binary variable indicating whether the patient met the criterion of suppression by 50% or more resulted in 95.6% accuracy, whereas substitution of this binary variable by percent suppression resulted in a model with 94.1% accuracy. There were no statistically significant differences among these models; their values for the c statistic, which is equivalent to the area under the curve in a receiver operating characteristic analysis, were all greater than 0.9. Logistic regression models indicate that the results of the dexamethasone suppression test add little to the differential diagnosis of ACTH-dependent Cushing's syndrome, especially after taking other clinical information into account. In our patient population, the sensitivity and specificity of the dexamethasone suppression test were less than those reported by others. However, because 20-33% of cases of ectopic ACTH syndrome are misdiagnosed with these logistic regression models, other techniques are necessary to achieve greater diagnostic accuracy.

Health services research and the endocrinologist

This article highlights the importance of health services research to endocrinologists. The content and goals of health services research are defined, and, with examples related to endocrinology, the field's focus and key themes are described and its methods and sources of data delineated. Considerations that informed readers should keep in mind when reading this literature are illustrated, with a recent example that has important implications for the role of endocrinologists in the management of diabetic patients.

Incidentalomas. A disease of modern technology

The optimal strategy for hormonal screening of a patient with any incidentally discovered adrenal or pituitary mass is unknown. Our review of the endocrinologic literature supports the view that such patients are at slightly increased risk for morbidity and mortality. There is a benefit of early diagnosis for at least for some of the disorders, suggesting the importance of case finding. The data in Tables 1 and 4 illustrate that clinically diagnosed hormone-secreting adrenal and pituitary tumors are far less common than incidentalomas. From a clinical perspective, our ability to determine accurately those at increased risk among the vast majority who are not at increased risk is poor. Given the limitations of diagnostic tests, effective hormonal screening requires a sufficiently high pretest probability to limit the number of false-positive results. This condition is met to varying degrees in the patient with an adrenal mass or small incidentally discovered pituitary mass but no signs or symptoms of hormone excess. Even the more common lesions such as pheochromocytoma and prolactinoma are relatively rare. Subjecting patients to unnecessary testing and treatment carries its own set of risks. Initial costs aside, testing may result in further expense and harm as false-positive results are pursued, producing the cascade effect described by Mold and Stein as a "chain of events (which) tends to proceed with increasing momentum, so that the further it progresses the more difficult it is to stop." The extensive evaluations performed in some patients with incidentally discovered masses may reflect the unwillingness of many physicians to accept uncertainty, even in the case of extremely unlikely diagnoses. This unwillingness may be driven, in part, by fear of potential malpractice liability, the failure to appreciate the influence of prevalence data on the interpretation of diagnostic testing, or other factors. Indeed, the major justification for further evaluation of these patients is not so much to avoid morbidity and mortality for rate patients who truly are at increased risk but rather to reassure those in whom further testing is negative (and to reassure ourselves). Physicians must take care not to create inappropriate anxiety in patients by overemphasizing the importance of an incidental finding unless it is associated with a realistic clinical risk. Our recommendations utilize currently available information to minimize the untoward effects of the cascade. As evidence accumulates, recommendations may need to be revised. The benefit of diagnosis of one of these adrenal or pituitary disorders must be considered in the context of the patient's overall condition. Studies are needed to analyze the utility in clinical practice of hormonal screening for these common radiologic findings. We need to use these studies to identify the critical gaps in our knowledge and to adopt the epidemiologic methods of evaluation of evidence that have been applied to preventive measures. We must be careful to recognize lead-time bias in which survival can seem to be lengthened when screening simply advances the time of diagnosis, lengthening the period of time between diagnosis and death without any true prolongation of life. Length bias refers to the tendency of screening to detect a disproportionate number of cases of slowly progressive disease and to miss aggressive cases that, by virtue of rapid progression, are present in the population only briefly. Endocrinologists must avoid the pitfalls of overestimation of disease prevalence and of the benefits of therapy resulting from advances in diagnostic imaging. Clinical judgment based on the best available evidence should be complemented and not replaced by laboratory data.

Hyperprolactinaemia and verapamil: prevalence and potential association with hypogonadism in men

OBJECTIVE

Verapamil has been associated with hyperprolactinaemia, but there have been no population-based studies. Our objective was to determine the prevalence and degree of hyperprolactinaemia associated with verapamil in the clinical setting.

DESIGN

Observation with cross-sectional and longitudinal components in the setting of an urban teaching hospital and its satellite out-patient clinics.

PATIENTS

Male out-patients excluding those taking other drugs known to raise PRL, renal failure and known primary hypothyroidism (1265 eligible subjects). Control subjects were drawn from eligible out-patients not taking verapamil.

MEASUREMENTS

Serum PRL levels, frequency of persistent hyperprolactinaemia and total testosterone levels.

RESULTS

Prolactin levels were obtained in 449 subjects on verapamil (35.5% response rate) and 166 controls. The proportions of individuals with hyperprolactinaemia (PRL > 460 mU/l) were 0.085 and 0.030 in the verapamil and control groups, respectively (P = 0.012, X2-test). The mean (+/- SD) serum PRL levels were 267 +/- 205 and 203 +/- 118 mU/l in the verapamil and control groups, respectively (P < 0.001, independent t-test). Of the 38 patients with previously determined elevated PRL levels, follow-up data were obtained in 25 (65.8%); one was found to have a pituitary adenoma and was excluded from the analysis. Fifteen of the 24 were still on verapamil (Group 1) and 14 (93.3%) continued to be hyperprolactinaemic. In 9 patients verapamil had been discontinued (Group 2) and all had normal PRL levels. Continued verapamil use was associated with persistent hyperprolactinaemia (odds ratio > 120, P < 0.00001). The mean +/- SD serum testosterone levels at follow-up were significantly lower in Group 1 (6.16 +/- 2.52 nmol/l) than in Group 2 (9.42 +/- 3.92 nmol/l, P = 0.029, independent t-test).

CONCLUSIONS

The prevalence of hyperprolactinaemia associated with verapamil use in this study of male out-patients was 8.5% (95% CI 5.9-11.1%). The persistence of hyperprolactinaemia when verapamil was continued (Group 1) and the return to normal PRL levels when verapamil was discontinued (Group 2) confirm verapamil's causal role in the development of hyperprolactinaemia. While low testosterone levels were common in both groups, testosterone levels were lower in patients on verapamil. Our data suggest that screening for hyperprolactinaemia should be considered in male patients taking verapamil.

Implementation of local guidelines for cost-effective management of hypertension. A trial of the firm system

OBJECTIVE

To evaluate the effects of an intensive intervention to implement guidelines for cost-effective management of hypertension on medication use and cost, blood pressure control, and other resource use.

DESIGN

Retrospective cohort trial based on the Cleveland Veterans' Affairs Medical Center Firm System.

SETTING

General internal medicine teaching clinic in a large university-affiliated Department of Veterans Affairs Medical Center.

PARTICIPANTS

All patients seen in the intervention firm (n = 1273) and control firm (n = 884) clinics in the 3-month period following the introduction of the guidelines.

INTERVENTIONS

The control firm received guidelines and usual education for the cost-effective outpatient management of hypertension. The intervention firm received guidelines plus intensive guideline-based education and supervision.

MEASUREMENTS AND MAIN RESULTS

The use of guideline medications was greater in the intervention firm as compared with the control. The intervention firm initiated more hydrochlorothiazide (HCTZ), 17.4% (95% confidence interval [CI] 14.8, 20.1) of patients versus 11.9% (CI 9.3, 14.8) in the control firm (p = .002). Atenolol was initiated in 7.2% (CI 5.6, 9.0) in intervention firm versus 4.7% (CI 3.2, 6.6) in the control (p = .03). In addition, the use of nonguideline medications was less in the intervention firm. The intervention firm initiated less long-acting nifedipine, 7.8% (CI 6.0, 9.8) versus 10.6% (CI 8.2, 13.5) in the control (p = .04). Blood pressure control demonstrated greater improvement in the intervention firm (p = .02). Use of guidelines was associated with decreased costs for antihypertensive medications in the intervention firm as a whole as compared with the control firm. There was no increased use in other measured resources in the intervention firm including the number of outpatient laboratory services obtained, clinic visits, emergency room visits, or hospitalizations.

CONCLUSIONS

Intensive implementation of guideline-based education and supervision was associated with an increased use of guideline medications, decreased use of costly alternative agents, and no decrement in the measured outcomes of care.

Verapamil-induced hyperprolactinemia complicated by a pituitary incidentaloma

OBJECTIVE

To describe a patient with an incidental pituitary lesion who experienced verapamil-induced hyperprolactinemia.

CASE SUMMARY

A patient experiencing impotence was found to have increased prolactin and low testosterone concentrations. Verapamil as a cause for his increased prolactin concentration was not considered initially. The patient underwent extensive testing to rule out a pituitary tumor. Magnetic resonance imaging showed a 6-mm lesion consistent with a pituitary microadenoma that had remained unchanged for 6 months. Verapamil therapy was discontinued and within 1 month the patient's prolactin concentration decreased from 46.8 to 14.4 micrograms/L, and has remained within normal limits.

DISCUSSION

We reviewed reports of verapamil-induced hyperprolactinemia. This case was unique as this patient had an incidental pituitary lesion that was not responsible for increasing the prolactin concentration in our patient, but rather complicated the identification of a drug-induced disorder.

CONCLUSION

The failure to identify the hyperprolactinemic effect of verapamil may have resulted in performing unnecessary radiologic procedures in this patient. This case highlights the importance of obtaining a medication history in patients with hyperprolactinemia.

Interdisciplinary integration for quality improvement: the Cleveland Veterans Affairs Medical Center Firm System

BACKGROUND

Many of the characteristics of Firm Systems lend themselves to the application of principles of continuous quality improvement (CQI). A Firm System is defined as two or more parallel practices organized on the principle of continuity of relationships between patients and an interdisciplinary group of health care professionals and trainees. Firm Systems are organized around the care of the patient or customer and emphasize access, continuity, and quality of care.

CASE STUDY

The Firm System was implemented at the Cleveland Veterans Affairs Medical Center (VAMC) not as a CQI initiative per se, but as an effort to coordinate the processes involved in the delivery of patient care. The primary goals of this implementation were to improve the quality of patient care, medical education, and health care research. The main strategy to deal with problems caused by uncoordinated care were to move from a departmental approach to an integrated interdisciplinary approach. This approach represented a paradigm shift within the organization that extended to planning, documentation, and the general work environment. Most important, the institution had leaders who were committed to the Firm System and willing to authorize resources to ensure its success.

CONCLUSION

VA hospitals are ideal settings for Firm Systems because they provide longitudinal, comprehensive care with a centralized, prepaid payment mechanism, and they have well-developed information systems that allow the random assignment of patients to Firms. Recommendations to others interested in implementing Firm Systems include creation of a written plan that can gain general support; identification of resources needed for successful implementation; remembering that the patient is the most important customer, as well as that complex systems have many customers; monitoring of performance; and the importance of randomizing patients and providers.

Pituitary tumors. Current concepts in diagnosis and management

Diagnostic advances have resulted in earlier and more frequent recognition of pituitary tumors. Pituitary tumors cause problems owing to the hormones they secrete or the effects of an expanding sellar mass--hypopituitarism, visual field abnormalities, and neurologic deficits. Prolactin-secreting tumors (prolactinomas), which cause amenorrhea, galactorrhea, and hypogonadism, constitute the most common type of primary pituitary tumors, followed by growth hormone-secreting tumors, which cause acromegaly, and corticotropin-secreting tumors, which cause Cushing's syndrome. Hypersecretion of thyroid-stimulating hormone, the gonadotrophins, or alpha-subunits is unusual. Nonfunctional tumors currently represent only 10% of all clinically diagnosed pituitary adenomas, and some of these are alpha-subunit-secreting adenomas. Insights into the pathogenesis and biologic behavior of these usually benign tumors have been gained from genetic studies. We review some of the recent advances and salient features of the diagnosis and management of pituitary tumors, including biochemical and radiologic diagnosis, transsphenoidal surgery, radiation therapy, and medical therapy. Each type of lesion requires a comprehensive but individualized treatment approach, and regardless of the mode of therapy, careful follow-up is essential.

High-dose dexamethasone suppression testing versus inferior petrosal sinus sampling in the differential diagnosis of adrenocorticotropin-dependent Cushing's syndrome: a decision analysis

Differentiation of adrenocorticotropin (ACTH)-dependent Cushing's syndrome between Cushing's disease and the occult ectopic ACTH syndrome is difficult. Simultaneous bilateral inferior petrosal sinus sampling (IPSS) for ACTH levels in response to corticotropin-releasing hormone has high diagnostic accuracy, but its cost-effectiveness has not been analyzed. In this study, decision analysis was used to compare two diagnostic strategies: IPSS versus high-dose dexamethasone suppression (HDD) followed by IPSS in those with a negative HDD test. Sensitivity analyses were performed for all variables. The authors found that at 100% accuracy, IPSS has an incremental cost-effectiveness ratio of $1,000,000 per life saved. Incremental cost, incremental effectiveness, and incremental cost-effectiveness are sensitive to the pretest probability of Cushing's disease, test characteristics, and test costs. As the pretest probability of Cushing's disease decreases, cost per life saved also decreases to less than 85%, the HDD strategy saves more lives and costs less. When the HDD test has a 83% sensitivity rate and a 100% specificity rate, the two strategy remains less expensive. The IPSS strategy saves lives whenever HDD specificity is less than 100%.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular cloning of mouse insulin-like growth factor binding protein 4 (IGFBP4) cDNA and expression of a fusion protein with IGF-binding activity

The TC-1 bone marrow stromal cell line expresses a 2.3 kb IGFBP-4 mRNA transcript. Reverse transcription/polymerase chain reaction was used to amplify the complete open reading frame of the insulin-like growth factor binding protein-4 (IGFBP-4) from poly(A)+ of a murine bone marrow stromal cell line (TC-1). Sequence analysis reveals that the murine IGFBP-4 is highly homologous to the rat IGFBP-4 and less so to the human IGFBP-4. The inferred amino acid sequence has a molecular weight of 25.7 kD. An IGFBP-4/maltose binding protein fusion peptide expression in the pMal-p2 vector produced a fusion protein exhibiting both IGFBP immunoreactivity and IGF-I binding activity with specificity characteristic of IGFBPs.

Ectopic ACTH syndrome and CRH-mediated Cushing's syndrome

The ectopic ACTH syndrome accounts for a substantial number of patients with naturally occurring Cushing's syndrome. Despite the progress achieved in elucidating the pathophysiology of Cushing's syndrome, clinicians continue to experience diagnostic and therapeutic challenges. This is especially true in those patients presenting with disease mediated by ectopically produced ACTH and CRH. Patients with these disorders may be indistinguishable based on clinical grounds or simple biochemical and radiologic testing from those with Cushing's disease. However, this differentiation is critical because their therapies differ. While clinical researchers continue to develop more effective diagnostic techniques and therapies, further advances in the molecular and cell biology of ACTH and CRH-producing tumors will undoubtedly shed light on the pathogenesis of this perplexing, fascinating and still controversial entity.

Cushing's syndrome and hypertension

Cushing's syndrome refers to the signs and symptoms that result from excessive glucocorticoid action, usually from endogenous production or exogenous administration. This article reviews the pathophysiology of hypertension in Cushing's syndrome and current concepts in the diagnosis and treatment of this disorder.

Management of gallstones in diabetic patients

The management of gallstones in diabetic patients has traditionally been considered problematic. Autopsy findings and uncontrolled studies have documented a higher prevalence of cholelithiasis in diabetics, and early reports showed dramatically increased perioperative morbidity and mortality for treatment of diabetics with acute cholecystitis. As a result, some authorities have recommended prophylactic cholecystectomy for diabetic patients with asymptomatic gallstones, which is in contrast to recommendations for nondiabetics. More recent investigators have shown comparable rates of operative morbidity and mortality for biliary surgery in diabetics when compared with the general population. Recent studies have questioned whether diabetes is an independent risk factor for gallstone formation. Decision analyses using these new data have shown that prophylactic cholecystectomy is not of clear benefit and should not be routinely recommended for diabetics with asymptomatic gallstones. We believe that available data, although limited, indicate that asymptomatic patients with diabetes do not benefit from screening for gallstones and that cholecystectomy should only be performed in cases of symptomatic cholelithiasis, as is the case in the general population.

Familial adrenocorticotropin-independent Cushing's syndrome with bilateral macronodular adrenal hyperplasia

Familial Cushing's syndrome is rare, and when it occurs, it is usually associated with primary micronodular dysplasia. We report two cases, a mother and daughter, who each presented with clinical features of Cushing's syndrome at age 38 yr and were found to have ACTH-independent macronodular adrenal hyperplasia. In each case, bilateral adrenalectomy revealed the massively thickened adrenal cortex with nodules up to 1.3 cm in diameter and hyperplasia between nodules. Dynamic testing showed no suppression of free cortisol with high dose dexamethasone and no stimulation of 17-hydroxycorticosteroids with metyrapone. Two samples of serum obtained preoperatively from one patient that showed ACTH immunoreactivity of 4.6 and less than 2.2 pmol/L, respectively, each showed less than 2.2 pmol/L ACTH bioactivity. The lack of suppression with high dose dexamethasone, lack of stimulation with metyrapone, and low levels of ACTH immunoreactivity and bioactivity suggest that the bilateral hyperplasia was not dependent upon ACTH. These patients represent the first cases of ACTH-independent macronodular adrenal hyperplasia occurring in two generations of one family and illustrate the expanding clinical spectrum of Cushing's syndrome.

Insulin-like growth factor I and erythropoiesis

The bone marrow, the primary site of hematopoiesis, is a self-renewing system consisting of a unique micro-environment that promotes the differentiation and proliferation of the various hematopoietic cell lines. While many critical factors necessary for red cell production have been identified, the regulation of erythropoiesis has not been completely elucidated. In addition to multi-lineage growth factors (e.g. interleukin 3 or 4) and lineage-specific hematopoietic growth factors (e.g. erythropoietin), several lines of evidence suggest a key role for insulin-like growth factor I (IGF-I). First, growth hormone stimulates erythropoiesis and IGF-I is known to mediate many of growth hormone's actions (somatomedin hypothesis). Second, factors in bovine serum and in serum from an anephric human with erythropoietic activity distinct from erythropoietin have been identified as IGFs. Third, IGF receptors are found on both erythrocyte precursors as well as mature erythrocytes. Fourth, in vitro IGF-I stimulates erythropoiesis in bone marrow cultures. Fifth, IGF-I administration to neonatal or hypophysectomized animals results in increased erythropoiesis in vivo. Recent studies indicate that IGF-I at physiologic concentrations stimulates erythropoiesis and that growth hormone's action is indirect, occurring via IGF-I. The physiologic source of IGF-I for the bone marrow may be delivery from the serum (an endocrine mechanism) or synthesis within the bone marrow by stromal or other cells (a paracrine mechanism). Our recent studies have shown that mouse bone marrow stromal cells secrete both IGF-I and IGF binding proteins (IGFBPs). The role of IGFBPs in erythropoiesis is not known, but they might modulate the local concentration of IGF-I.(ABSTRACT TRUNCATED AT 250 WORDS)

The Cleveland Veterans Affairs Medical Center firm system

Hospital-based "firms" provide a means for combatting the fragmentation experienced by both patients and caregivers in the modern teaching hospital environment. A "firm" is an academic group practice that includes attending physicians, physician trainees, nurses, other staff, and patients. Each person's relationship with a firm lasts throughout his or her association with a particular institution. This article describes the firm system that was recently implemented on the Medical Service of the Cleveland VAMC. This system incorporates both inpatient and outpatient general medical services and provides for unbiased assignment of patients, physicians, and nurses.

Somatostatin-producing neuroendocrine tumor of the ampulla (ampullary somatostatinoma). Evidence of prosomatostatin production

Two cases of somatostatin-producing ampullary neuroendocrine tumors (somatostatinoma) are reported. The authors have characterized their immunoreactivity using antibodies specific for the amino- and carboxyl-terminal portions of prosomatostatin, the precursor of somatostatin in the normal synthetic pathway. Cytoplasmic staining was found using each of these two antibodies in the tumor cells of both ampullary somatostatinomas as well as in the cytoplasm of cells in the hypothalamus, crypt cells of the duodenal mucosa, mucosal cells of the biliary tract, D cells of the pancreatic islets, and parafollicular cells of fetal thyroid. These studies suggest that the synthesis of somatostatin in ampullary somatostatinomas occurs through the normal pathway from the precursor prosomatostatin.

Cushing's syndrome with cranial and pulmonary lesions: necessity for tissue diagnosis

This report describes two cases of Cushing's syndrome associated with radiologic abnormalities in the lung and brain. In both cases, the pathologic diagnosis of the intracranial lesion was unsuspected and prompted changes in management. These cases illustrate that the etiology of pulmonary and central nervous system mass lesions in patients with Cushing's syndrome may not be predicted on clinical grounds or by conventional radiologic methods. A tissue diagnosis is essential as a guide to appropriate management, and biopsies of such lesions are indicated.

Secretion of insulinlike growth factor I and insulinlike growth factor-binding proteins by murine bone marrow stromal cells

Insulin-like growth factor I (IGF-I) stimulates hematopoiesis. We examined whether bone marrow stromal cells synthesize IGF-I. Secretion of IGF-I immunoreactivity by cells from TC-1 murine bone marrow stromal cells was time-dependent and inhibited by cycloheximide. Gel filtration chromatography under denaturing conditions of TC-1 conditioned medium demonstrated two major peaks of apparent IGF-I immunoreactivity with molecular weights of approximately 7.5-8.0 kD, the size of native IGF-I, and greater than 25 kD. Expression of IGF-I mRNA was identified by both RNase protection assay and reverse transcription/polymerase chain reaction. To determine whether the greater than 25-kD species identified by RIA possessed IGF-binding activity, a potential cause of artifactual IGF-I immunoreactivity, charcoal adsorption assay of these gel filtration fractions was performed. The peak of IGF-binding activity coeluted with apparent IGF-I immunoreactivity suggesting that TC-1 cells secrete IGF-binding protein(s). Unfractionated conditioned medium exhibited linear dose-dependent increase in specific binding of [125I]-IGF-I with a pattern of displacement (IGF-I and IGF-II much greater than insulin) characteristic of IGF-binding proteins. Western ligand analysis of conditioned medium showed three IGF-I binding species of approximately 31, 38, and 40 kD. These data indicate that TC-1 bone marrow stromal cells synthesize and secrete IGF-I and IGF-binding proteins and constitute a useful model system to study their regulation and role in hematopoiesis.

Secretion of insulin-like growth factor I and its binding proteins by collecting duct cells

Insulin-like growth factor I (IGF-I) has been found in the kidney, particularly in the collecting duct in the rat. Since cultured rabbit collecting duct cells constitute a convenient system for in vitro studies, we have examined whether these cells secrete IGF-I. Culture medium conditioned by collecting duct cells was concentrated by reverse phase chromatography and applied to a Sephadex G100 column equilibrated in a denaturing buffer. Two major species with apparent molecular weights of 7.5 and greater than 25 kilodaltons (kD) were identified by IGF-I RIA. A smaller amount of 10 kD species was also observed. Further characterization of 7.5 kD IGF-I immunoreactive species by reverse phase HPLC showed that it eluted in a single peak. To determine whether the higher molecular weight species possessed IGF-I binding activity, appropriate fractions were desalted, incubated with [125I]IGF-I (thr59) for two hours at 30 degrees C and applied to a Sephadex G100 column equilibrated in a non-dissociating buffer. The major peak of radioactivity was confined to a high molecular weight region; there was no radioactivity in the fractions corresponding to 7.5 kD. Western ligand analysis of unreduced conditioned medium identified two IGF-I binding species of 25 and 30 kD, similar in size to species observed in normal rabbit serum. 125I-IGF-I binding as assessed in a charcoal adsorption assay could be displaced by IGF-I and IGF-II but not by insulin. Further characterization of the 10 kD peak of IGF-I immunoreactivity indicated that it did not possess IGF-I binding activity.(ABSTRACT TRUNCATED AT 250 WORDS)