Anxiety and depression in an internal medicine resident continuity clinic: difficult diagnoses

OBJECTIVE

To determine the prevalence of anxiety and depression in a residents' clinic and if these diagnoses are associated with patients being perceived as difficult, as well as how often these diagnoses are documented in the patients' charts.

METHODS

This was a cross-sectional study conducted in a general internal medicine residents' clinic. A total of 135 patients were given the Primary Care Evaluation of Mental Disorders questionnaire (DSM-IIIR version) and their physicians filled out the Difficult Doctor-Patient Relationship Questionnaire after the visit. Charts were reviewed for documentation of a diagnosis of anxiety or depression.

RESULTS

Major depression was present in 26 percent, dysthymia 16 percent, major depression in partial remission 9 percent, generalized anxiety disorder 13 percent, and panic disorder 7 percent. Overall, 38 percent had at least one and 21 percent had more than one diagnosis. Of patients with one psychiatric diagnosis, 9 percent were classified as difficult versus 100 percent of patients with four diagnoses. Documentation of depression was noted for 43 percent of patients with major depression but only 9 percent with an anxiety disorder.

CONCLUSIONS

Anxiety and depression were very common among the patients in this clinic, and increasing numbers of diagnoses were associated with patients being classified as difficult. Residents diagnosed depressive disorders as often as practicing physicians in other studies, but anxiety less well. The high prevalence of mental disorders has implications for resident education in that they need to be prepared to care for these patients, but residents also may benefit from exposure to sites with more typical prevalences of these illnesses.

Healthy patients who perceive poor health: why are they worried sick?

OBJECTIVE

To explore characteristics of patients who are physically healthy but who perceive poor health by investigating the hypothesis that mental health problems, financial strain, and deficiencies in social support underlie why these patients are "worried sick."

METHODS

Three hundred forty-eight continuity patients in 2 rural primary care practices were administered the PRIME-MD, the MOS SF-36, a health-related worry (1-item, 5-point) scale, the MOS social support survey, and perceived economic strain instruments. The patient's physician rated physical health on a 10-point scale. Health care utilization was defined as the number of office visits and total office and laboratory charges for 6 months before and after the interview date.

RESULTS

Two hundred thirty-seven patients (group A) scored in the upper and middle terciles on the MOS health perceptions scale. One hundred eleven patients scored in the lower tercile on health perceptions: 59 (group B) were rated as having good physical health (physical health rating > 6) and 52 (group C) as having poor health (rating < or = 6). The "worried sick" patients (group B) resembled Group A with regard to physical health, but resembled the sick (group C) with regard to all MOS functional scales, prevalence of mental health diagnoses, and worry. Social support was similar across groups. Only 1 of 3 measures of economic strain was less in group A than B and C.

CONCLUSIONS

Our measures of mental health problems, financial strain, and deficiencies in social support accounted only in part for the differences among the three groups. Other explanations of why some are "worried sick" require study, such as other life stressors and personality traits.

The role of spiral volumetric computed tomography in the diagnosis of pulmonary embolism

To evaluate the evidence for the use of spiral volumetric computed tomography (SVCT) in the diagnosis of acute pulmonary embolism (PE), the 11 English-language studies published through July 1998 that compared SVCT with a reference standard for PE were systematically reviewed. Among the reviewed studies, methodological problems were common. Only 5 of these studies fulfilled 5 of 11 basic standards addressing important issues in diagnostic test research. The reported sensitivities of SVCT compared with pulmonary angiography varied widely (64%-93%), which was likely the result of differences in study populations. Spiral volumetric computed tomography may be relatively sensitive and specific for diagnosing central pulmonary artery PEs, but it is insensitive for diagnosing subsegmental clots. Spiral volumetric computed tomography may have a role as a "rule-in" test for large central emboli, but additional research is required to establish its place in clinical practice.

Effectiveness of percutaneous coronary interventions to prevent recurrent coronary events in patients on chronic hemodialysis

Patients on chronic hemodialysis undergoing percutaneous coronary revascularization have similar rates of procedural success and in-hospital event rates when compared with a matched cohort. However, patients on chronic hemodialysis have a marked increase in 36-month target vessel revascularization, myocardial infarction, and death rates.

Predictors of interest in prostate-specific antigen screening and the impact of informed consent: what should we tell our patients?

PURPOSE

Screening for prostate cancer with the prostate-specific antigen (PSA) remains highly controversial. We sought to discern which patient factors predict interest in the PSA and how informed consent impacts these predictors.

PATIENTS AND METHODS

In a randomized trial that found that informed consent decreases patient interest in PSA screening, potential predictors of interest were analyzed separately in the uninformed (n = 102) and informed (n = 103) cohorts to examine the effects of the informational intervention.

RESULTS

Univariate predictors of PSA screening interest (P < 0.05) among uninformed patients included perceived efficacy of screening, perceived seriousness of an abnormal PSA, and willingness to accept treatment risks. Among patients who had been informed about PSA screening, univariate predictors included family history of prostate cancer, perceived susceptibility to prostate cancer, age (inverse association), and perceived efficacy, although informed patients rated PSA efficacy significantly lower than uninformed patients (P < 0.001). In multivariate logistic regression modeling for the uninformed cohort, perceived screening efficacy (P < 0.001), perceived seriousness (P < 0.05), and willingness to accept treatment risks (P < 0.05) together were significant predictors of PSA screening interest. Among informed patients, perceived efficacy (P < 0.001), perceived susceptibility (P = 0.01), and younger age (P = 0.01) together predicted interest in screening.

CONCLUSIONS

In contrast to uninformed patients, patients given information about PSA screening and prostate cancer are more likely to be interested in screening if they have a family history of prostate cancer, are younger, or otherwise consider themselves susceptible to developing prostate cancer. Uninformed patients are more likely to base their screening interest on the perceived seriousness of prostate cancer and on their willingness to accept treatment risks.

Fever in the clinical diagnosis of acute pyelonephritis

Acute pyelonephritis is a clinical syndrome that can be confused with other conditions. To investigate this problem, a retrospective cohort study was conducted using two mutually exclusive sets of clinical criteria for acute pyelonephritis in women 15 years of age or older who presented to the emergency department of a university hospital. All patients had pyuria, and one group had documented fever (temperature of > or = 37.8 degrees C) while the other group had a temperature of < 37.8 degrees C but had other evidence of possible upper tract infection. The study cohort was comprised of 103 febrile and 201 afebrile patients. Afebrile hospitalized patients were ultimately found to have another diagnosis more often than were the febrile hospitalized patients (35% v 7%; P = .02), and the afebrile nonhospitalized patients were more likely to have another diagnosis than were the febrile nonhospitalized patients (13% v 0%; P = .004). Other diagnoses included cholecystitis, pelvic inflammatory disease, and diverticulitis. The positive predictive value of the definition of pyelonephritis in the febrile group was 0.98, and it was 0.84 for the afebrile group. Physicians examining patients with clinical evidence of acute pyelonephritis but without objective fever should be alert for alternative diagnoses.

D-dimer testing and acute venous thromboembolism. A shortcut to accurate diagnosis?

D-dimer fragments can be measured easily in plasma and whole blood, and the presence or absence of D-dimer could be useful in the diagnostic evaluation of venous thromboembolism. We systematically reviewed the English literature for articles that compared D-dimer results with those of other tests for deep venous thrombosis or pulmonary embolism. Twenty-nine studies were selected for detailed review, and we noted wide variability in assay performance, heterogeneity among subjects, and failure to define absence or presence of venous thromboembolism by a comprehensive criterion standard for diagnosis. These methodologic problems limit the generalizability of the published estimates of D-dimer accuracy for deep venous thrombosis or pulmonary embolism, and the clinical utility of this potentially important test remains unproved.

The prevalence of mental disorders in rural office practice

OBJECTIVE

To determine the prevalence of mental disorders in rural primary care office practice.

DESIGN

Patient interview; chart review.

SETTING

Two rural primary care office practices.

PATIENTS

Three hundred-fifty scheduled or walk-in patients age 18 years or older.

MEASUREMENTS

Medical Outcomes Study 36-Item Short-Form Health Survey (MOS SF-36), the Primary Care Evaluation of Mental Disorders (PRIME-MD), physical health using Greenfield's index of coexistent disease (ICED), and health care utilization using the number of office visits and total office and laboratory charges six months before until six months after the interview.

RESULTS

Of these patients 34% met criteria for one or more of the 18 mental disorders evaluated by the PRIME-MD; 19% met criteria for specific disorders according to criteria from the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (DSM-III-R). Mood disorders were most common (21.7%), followed by anxiety disorders (12.3%), somatoform disorders (11.1%), probable alcohol abuse or dependence (6.0%), and eating disorders (2.0%). By logistic regression, there was an association of age, sex, race (black), and education with lower prevalence of various mental disorder categories. Even after adjustment for demographic variables and physical health (ICED score), those with PRIME-MD diagnoses had significantly lower function as measured by the eight MOS SF-36 scales and higher utilization of office services (p < .001).

CONCLUSIONS

The prevalence of mental disorders in rural primary care office practice is as high as in urban office practice.

Vena cava filter devices

Vena cava filters are effective in preventing pulmonary embolism (PE) in patients with deep vein thrombosis or PE who either have contraindications to anticoagulation or have sustained a PE despite adequate anticoagulation. Although vena cava filters are not without complications, clinically significant morbidity and mortality are low. The use of vena cava filters as primary prophylaxis or therapy for deep vein thrombosis and PE should await the results of controlled trials.

Predictors of survival following in-hospital cardiopulmonary resuscitation. A moving target

BACKGROUND

Counseling patients about the risks and benefits of in-hospital cardiopulmonary resuscitation (CPR) can potentially reduce patient suffering and hospital costs. However, there is currently much disagreement regarding the overall rate of in-hospital CPR survival and characteristics that identify patients more or less likely to survive CPR.

METHODS

The charts of all adults who were pulseless and received basic CPR at a 720-bed university hospital during 1990 and 1991 were reviewed. Patients were excluded if cardiac arrest occurred outside the hospital or in the emergency department, operating room, recovery room, or cardiac catheterization laboratory. Each patient's chart was reviewed to determine the presence of explicitly defined clinical characteristics.

RESULTS

Overall, 50 (16.0%) of 313 patients survived to discharge. Before arrest, only impaired functional capacity and sepsis identified patients unlikely to survive CPR. Of adults suffering cardiac arrest during the study period, only 22% underwent CPR, including 13.0% of those with cancer and 18.1% of those 70 years or older.

CONCLUSIONS

The use of do-not-resuscitate orders to exclude patients who were inappropriate candidates for CPR may explain why the survival rate reported here is higher than similar reports and why more clinical characteristics were not found to predict CPR survival. Investigators of in-hospital CPR should use explicit criteria to describe the conditions studied and report survival for patients who receive basic CPR. The impact of do-not-resuscitate orders on survival rates must be considered. Functional capacity deserves further investigation as a predictor of CPR survival.

Differences in case definitions as a cause of variation in reported in-hospital CPR survival

To determine the effect of different case definitions on reported survival following in-hospital cardiopulmonary arrest, the authors reviewed the charts of 411 patients for whom a nurse completed a cardiac arrest form at a university hospital during a two-year period. Survival to discharge was 16.0% for patients who required basic cardiopulmonary resuscitation (chest compression and pulmonary ventilation), 18.6% for patients who were pulseless and apneic, 23.0% for patients who were pulseless or apneic, and 28.2% for all 411 patients for whom a cardiac arrest form was completed. These results demonstrate that reported survival to discharge following in-hospital cardiac arrest varies widely depending on the case definition that is used.

ED management of acute pyelonephritis in women: a cohort study

Various treatment strategies are currently used in the management of acute pyelonephritis, with some patients being treated as inpatients and others as outpatients. To better describe the clinical course of patients with this condition and the management strategies of physicians treating these patients, a retrospective cohort study of febrile nonpregnant women presenting to the emergency department with clinical evidence of acute pyelonephritis was conducted. Acute pyelonephritis was defined as infected urine (> or = 7 white blood cells/high-power field and/or urine culture with > or = 10(4) colony-forming units [CFU]/mL) and fewer (> or = 37.8 degrees C) without other source. Between October 1990 and September 1991, 28 hospitalized and 83 nonhospitalized patients satisfied these criteria. Data were abstracted from hospital charts, and clinical outcomes were determined from chart reviews and telephone or mailed questionnaires. The hospitalized patients were significantly older (odds ratio [OR] = 1.07), had higher temperatures (OR = 6.12), and were more likely to have diabetes (OR = 10.57), genitourinary tract abnormalities (OR = 10.53), and vomiting (OR = 12.17) than the nonhospitalized patients. Sixty-six (80%) of the nonhospitalized patients were treated with a single dose of parenteral antibiotic (usually gentamicin or ceftriaxone) before discharge on oral antibiotics. Seventy-one (86%) were treated with oral trimethoprim-sulfamethoxazole. Follow-up was obtained for 75 (90%) of the nonhospitalized patients. Nine (12%) of the 75 returned because of symptoms of acute pyelonephritis, with 8 returning within 1 day of the initial visit. Seven of those returning were admitted. All responded to additional antibiotic therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of a class IV hurricane on emergency department operations

The objective of this study was to determine the impact on emergency department (ED) operations of Hurricane Hugo, a class IV hurricane that struck Charleston, South Carolina, on September 21, 1989. The study design was a retrospective record-based descriptive study and mail survey of the ED of a 300-bed regional medical center directly in the path of the storm. During the 3 weeks after the storm, ED patient volume increased 19% over that of the 3 weeks before the storm. Increased visit volumes were evident for at least 3 months. Compared with a similar period of the previous year, there was an increase in the proportion of patients seen for lacerations of all types, puncture wounds, stings, and falls. Sixty-two percent of physician offices were still closed 7 days after the storm. The direct effects of a class IV hurricane on ED operations included major alterations in the volume and types of patient visits. Because of the evacuation of approximately 40% of the coastal population and storm damage hindering travel, the increase in visit volume was less in magnitude but of longer duration has been reported in class III hurricanes.

Inferior vena cava filters. Indications, safety, effectiveness

BACKGROUND

Preventing pulmonary embolization by interrupting vena caval flow has been attempted since 1893. Inferior vena cava (IVC) filters have been available for 20 years, and currently there are five filters commercially available in the United States (Greenfield filter, Titanium Greenfield filter, Simon-Nitinol filter, Bird's Nest filter, and LGM or Vena Tech filter) and two other filters under development (Amplatz filter and Günther filter). Although these devices are widely used, their clinical utility and safety have not been completely evaluated. Controlled clinical trials to determine the clinical role for IVC filters have not been attempted, but numerous case series describing the outcomes of the seven current filters have been published. We have systematically reviewed these studies to clarify what is known about the indications, safety, and effectiveness of IVC filters.

METHODS

Using the MEDLINE database, all English-language publications since 1970 that included follow-up clinical information after filter insertion were reviewed and eight methodologic guidelines were employed to assess the scientific quality of the clinical information.

RESULTS

Twenty-four case series were reviewed: 16 concerned the Greenfield filter (1632 patients), and eight dealt with newer designs (925 patients). Commonly noted methodologic problems included failure to report the initial extent of thromboembolic disease, incomplete description of the patient assembly process, and incomplete and potentially biased outcome assessment. Recurrent clinical pulmonary embolism was rare after filter placement, and only eight deaths from pulmonary embolism were reported. Filter complications were common but rarely life threatening; four (0.16%) deaths from filter complications were noted among the reviewed studies. Thrombotic complications following filter placement included insertion-site deep vein thrombosis and IVC obstruction. These events were rare, but they occurred with all filter types.

CONCLUSIONS

Inferior vena cava filters appear to be effective in preventing recurrent pulmonary embolism. Despite the large published experience with IVC filters, many questions remain about their indications, safety, and effectiveness. Anticoagulant therapy, if not contraindicated, should be used in conjunction with filters. While there is no ideal filter, some situations call for specific filters. Filter selection and insertion require experience, modern angiographic technique, and collaboration between clinicians caring for patients and the interventional radiologists or surgeons inserting the device.

Home visits in a rural office practice: clinical spectrum and effect on utilization of health care services

OBJECTIVE

To describe the clinical features of home visits and their role in continuity of care, costs, and benefits in a rural office practice.

DESIGN

Prospective study of all home visits performed during a 26-month period.

SETTING

A general medicine teaching office practice located in rural Virginia.

PATIENTS

All persons to whom home visits were made during the study period.

MAIN RESULTS

138 home visits were made to 47 patients who had a mean age of 73.2 years. Home visits accounted for 1.4% of patient encounters in the practice, required a mean of 7.1 miles of one-way travel and a mean of 48 minutes, including travel time, to complete, and generated $36 in income per visit. Most patients (27 of 47) were not permanently homebound. Reasons for patients' being homebound were grouped into six categories (acute illness, frail elderly, terminal illness, advanced chronic disease, neurologic problem, and miscellaneous reasons). The reasons for visits were grouped into four categories (acute self-limited illness, exacerbation of chronic disease, routine follow-up of chronic disease, and psychosocial problem). Physicians judged that 80% of home visits represented appropriate use of their services. In addition, 46% of home visits made an emergency room visit unnecessary, and 9% made a hospital admission unnecessary. At the time of 75% of home visits, physicians reported personal benefits of making the visit.

CONCLUSIONS

Home visits have an important role in the care of ambulatory as well as permanently homebound patients. While physicians judged most home visits to be appropriate and personally beneficial, these visits required more time and generated less revenue than did office visits for comparable problems. Because home visits generated as well as prevented the use of medical services, their impact on the overall cost of medical care in this setting is unclear.

Ciprofloxacin-induced acute interstitial nephritis

Acute renal failure is a complication attributed to numerous medications. Few cases linked to the newer fluoroquinolones have been described. We report a case of acute interstitial nephritis confirmed by renal biopsy that developed in a patient within days of starting ciprofloxacin therapy. A review of the literature reveals common clinical manifestations of this rare adverse effect. Clinicians should be aware of this potential complication of ciprofloxacin use.

Optimal management of suspected lower-extremity deep vein thrombosis. An evaluation with cost assessment of 24 management strategies

Traditionally, patients suspected to have lower-extremity deep vein thrombosis have undergone venography, which is invasive, is expensive, and may cause deep vein thrombosis in healthy individuals. Recent studies have shown the safety and efficacy of alternative noninvasive approaches that employ impedance plethysmography or real-time ultrasonography. We compared these tests using decision analysis to model the consequences of 24 different management strategies for ambulatory patients suspected to have deep vein thrombosis. We also calculated the incremental cost per additional life saved for each strategy. Our analysis revealed that the optimal approach was to perform real-time ultrasonography followed by anticoagulation therapy if deep vein thrombosis is found. This approach was both effective and cost saving compared with no testing or treatment. Serial follow-up studies of patients whose initial study suggested no DVT saved additional lives, but at a cost of $390,000 per each additional life saved for patients with one follow-up study and $3.5 million per each additional life saved for patients with a second follow-up study. Venography should play a limited role in the contemporary evaluation of patients suspected to have deep vein thrombosis. Future research should focus on the determination of clinical predictors of patients who should undergo serial examinations.

Technetium-99m-RBC venography in the diagnosis of deep venous thrombosis of the lower extremity: a systematic review of the literature

We systematically reviewed the six articles from the English-language medical literature, since 1979, which compared 99mTc-RBC venography with contrast venography for the diagnosis of deep venous thrombosis (DVT) of the lower extremity. The studies were generally small in size and poorly compliant with methodologic standards for diagnostic test research. There was considerable variation in both how the 99mTc-RBC venograms were performed and how they were interpreted. Sufficient clinical information on the patients was not provided. Although the overall sensitivities and specificities were high with a mean sensitivity of 0.89 and a mean specificity of 0.84, the small numbers of patients resulted in wide 95% confidence intervals. For distal disease, with only a total of 14 patients studied, the 95% confidence intervals were particularly broad. Although 99mTc-RBC venography is a promising technique, future studies with larger numbers of patients and closer adherence to methodologic standards are required.

Axillary and subclavian venous thrombosis. Prognosis and treatment

To clarify the prognosis of axillary and subclavian deep venous thrombosis and to determine which clinical factors influence its sequelae, we systematically reviewed the English-language literature published on this subject since 1950. Seventy-one case reports and 17 case series describing a total of 329 patients met our inclusion criteria for detailed review. There were major deficiencies in the quality, as well as quantity, of the available clinical data: few patients were enrolled at axillary and subclavian deep venous thrombosis inception, and outcome assessments were susceptible to bias and based on insensitive diagnostic tests. Posttreatment symptoms were reported in 34% of cases, pulmonary embolism in 9.4% (one half documented by lung scan or angiography), and death in 1.2% (three of four deaths due to pulmonary emboli). These complications occurred regardless of etiologic category (spontaneous, catheter related, or miscellaneous). Thrombolytic agents and surgery, in addition to anticoagulation, were often used to treat axillary and subclavian deep venous thrombosis, but there were no controlled trials to support any one approach. Until such trials are performed, therapy should be based on the anticoagulation regimens proved to be effective for deep venous thrombosis of the lower extremity. In selected patients, thrombolytic therapy and surgery may have important roles.

Healthy patients who perceive poor health and their use of primary care services

OBJECTIVE

To determine what proportion of patients who have poor health perceptions are physically healthy and to explore why some patients perceive a healthy state while others perceive illness.

DESIGN

A prospective consecutive series of office patients completed the Rand Corporation's General Health Perceptions Questionnaire, and their physicians rated their physical health. Their use of health care services was determined for the following 12 months.

SETTING

A rural teaching office practice.

PATIENTS

Of 243 adult patients asked to complete the questionnaire, 32 were excluded, for dementia (8), illiteracy (4), illness (8), incomplete questionnaires (6), and other reasons (6). 208 patients (86%) formed the final study group.

MEASUREMENTS AND MAIN RESULTS

62 of 208 patients had poor health perception scores. 39 of the 62 were rated by physicians as physically healthy and were not statistically different in physical health ratings or numbers of prescribed medications from the 146 patients who had higher health perception scores. However, these 39 patients had significantly more health-related worry, acute pain, and depression than did the other 146 patients. They also made more office visits and telephone calls and had higher total primary care charges.

CONCLUSIONS

This study suggests that 21% of adult primary care patients (39 of 208) have health perceptions lower than expected for their levels of physical health. These low health perceptions are correlated with increased emotional distress and higher utilization of health care resources. Strategies to identify these patients and interventions to improve their views of their health could reduce utilization.

A patient-based system for describing ambulatory medicine practices using diagnosis clusters

OBJECTIVE

To develop a patient-based classification system to describe the clinical content of ambulatory medicine practices.

DESIGN

A system of 100 diagnosis clusters was developed based on retrospective review of computerized problem lists of patients from a university practice, and then applied to the problem lists of patients in a community practice. Chart review of a 5% random sample (n = 184) of university practice patients who had problem lists was carried out to assess the accuracy of the computerized problem lists.

SETTING

A university ambulatory medicine practice and a community ambulatory medicine practice.

PATIENTS/PARTICIPANTS

For the same one-year period, all 4,490 patients seen in the university practice and all 1,294 patients seen two or more times in the community practice.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 27,634 problems listed for university patients and the 5,648 problems listed for community patients, 22,629 (82%) and 4,924 (87%), respectively, were assigned to diagnosis clusters. For the university and community practices, the mean numbers of problems per patient were 6.1 (SD 5.4) and 4.4 (SD 3.7), and the mean numbers of diagnosis clusters per patient were 4.5 (SD 3.7) and 3.6 (SD 3.0), respectively. Among the ten most common diagnosis clusters in both practices were HYPERTENSION, SYMPTOM OR SIGN, OBESITY, and DIABETES. Only 18% (SD 3%) of patient problem lists in the university practice omitted one or more chronic, important medical problems (e.g., hypertension, dementia, COPD).

CONCLUSIONS

This system of diagnosis clusters effectively and efficiently described the clinical content of two types of internal medicine practices, and has important applications in medical education, epidemiology, clinical and health services research, and public policy.

Suspected pulmonary embolism and lung scan interpretation: trial of a Bayesian reporting method

OBJECTIVE

To determine whether a Bayesian method of lung scan (LS) reporting could influence the management of patients with suspected pulmonary embolism (PE).

DESIGN

1) A descriptive study of the diagnostic process for suspected PE using the new reporting method; 2) a non-experimental evaluation of the reporting method comparing prospective patients and historical controls; and 3) a survey of physicians' reactions to the reporting innovation.

SETTING

University of Virginia Hospital.

PATIENTS

Of 148 consecutive patients enrolled at the time of LS, 129 were completely evaluated; 75 patients scanned the previous year served as controls.

INTERVENTION

The LS results of patients with suspected PE were reported as posttest probabilities of PE calculated from physician-provided pretest probabilities and the likelihood ratios for PE of LS interpretations.

RESULTS

Despite the Bayesian intervention, the confirmation or exclusion of PE was often based on inconclusive evidence. PE was considered by the clinician to be ruled out in 98% of patients with posttest probabilities less than 25% and ruled in for 95% of patients with posttest probabilities greater than 75%. Prospective patients and historical controls were similar in terms of tests ordered after the LS (e.g., pulmonary angiography). Patients with intermediate or indeterminate lung scan results had the highest proportion of subsequent testing. Most physicians (80%) found the reporting innovation to be helpful, either because it confirmed clinical judgement (94 cases) or because it led to additional testing (7 cases).

CONCLUSIONS

Despite the probabilistic guidance provided by the study, the diagnosis of PE was often neither clearly established nor excluded. While physicians appreciated the innovation and were not confused by the terminology, their clinical decision making was not clearly enhanced.

Use of ambulatory electrocardiographic (Holter) monitoring

PURPOSE

To evaluate the clinical efficacy of ambulatory electrocardiographic (ECG) monitoring and to develop guidelines for its use in clinical practice.

DATA IDENTIFICATION

Studies reported since January 1978 were identified both through computer searches using Index Medicus and extensive manual searching of bibliographies of identified articles.

STUDY SELECTION

Only studies that fulfilled methodologic criteria designed to limit bias were reviewed.

DATA EXTRACTION

Information describing population and study results was assessed in four major categories (variability, diagnosis, prognosis, and therapy guidance) for both arrhythmia monitoring and ST-segment analysis.

RESULTS OF DATA ANALYSIS

The day-to-day variability of arrhythmia and myocardial ischemia detected by ambulatory ECG monitoring may be considerable in an individual patient. Caution must therefore be used in interpreting serial tests. Ambulatory ECG monitoring with diary correlation permits documentation of cardiac arrhythmias causing symptoms, but the diagnostic yield is low unless symptoms are frequent. Such monitoring can provide information about prognosis in patients after acute myocardial infarction. The amount of prognostic information obtained is modest and is outweighed by other measures. There is insufficient information to make conclusions about such monitoring and prognosis in other conditions. Serial ambulatory ECG monitoring may be used to assess the effect of an antiarrhythmic drug in patients with frequent and reproducible ventricular ectopy. The effect of arrhythmia suppression on survival is uncertain. Because of its low sensitivity and specificity, analysis of ST-segment changes during ambulatory ECG monitoring is inaccurate in establishing or excluding the presence of coronary disease. Although anti-ischemic interventions reduce the frequency and duration of ST-segment changes on monitoring, there are no data on the utility of using reduction or elimination of the changes as the endpoint of therapy.

CONCLUSIONS

Ambulatory ECG monitoring can provide diagnostic, prognostic, and therapeutic information in many situations, but similar information often may be better obtained in other ways.

Plasma DNA. A simple, rapid test for aiding the diagnosis of pulmonary embolism

Previously, we reported that the sensitivity of plasma DNA for patients with pulmonary emboli was 83 to 88 percent. To confirm these findings in a more comprehensive study, we collected plasma samples from 137 consecutive patients undergoing 148 ventilation-perfusion lung scans for pulmonary embolism. DNA was measured using a counter-immunoelectrophoresis technique that used high titer precipitating double-stranded DNA antibody from a patient with systemic lupus erythematosus. In addition to 17 patients (17 lung scans) excluded for not having plasma collected, 32 patients (37 lung scans) were excluded for having either a condition other than pulmonary embolism that could be associated with plasma DNA or for having nonacute symptoms. Eighteen of 22 patients with a diagnosis of pulmonary embolism (defined by either a high probability lung scan or abnormal pulmonary angiogram) had detectable plasma DNA. Only four of 27 patients without pulmonary embolism (defined by either a normal lung scan or normal pulmonary angiogram) had plasma DNA detected. Based on these results, plasma DNA had a sensitivity of 82 percent and a specificity of 85 percent for this condition. Plasma DNA is a promising test for pulmonary embolism and could help physicians interpret equivocal lung scan findings and thereby clarify difficult decisions such as the need for pulmonary angiography.

Restoring balance to internal medicine training: the case for the teaching office practice

Medical residents require an experience beyond the tertiary care hospital to understand many aspects of contemporary medical practice and to make informed career choices. To provide this balanced training, the University of Virginia has operated for 10 years an internal medicine teaching office practice to provide an outpatient experience similar to private practice. It allows residents to work closely with general internal medicine faculty and introduces them to the knowledge and skills necessary to establish and manage a successful practice. The curriculum of the 10 week rotation includes patient care in the office and by telephone, nursing home and home visits, tutorials and seminars on primary care and office management topics, and training in the use of microcomputers. A survey of 46 (92%) of the first 50 residents completing the rotation revealed that the content of the rotation was valuable, the rotation substantially influenced career choices, and the rotation helped provide a balanced view of internal medicine practice.

Health perceptions of primary care patients and the influence on health care utilization

This prospective study was conducted to determine the influence of primary care patients' health perceptions on their utilization of health care services. Patients' health perceptions were measured using the RAND Corporation's General Health Perceptions Questionnaire. Physicians provided scores of how they thought the patients perceived their health and of actual physical and emotional health. Utilization data (number of office visits, number of telephone calls to the physician, and ambulatory charges) were evaluated for a 12-month period after completion of the questionnaire. Of 208 patients, 62 (30%) patients with health perceptions scores less than 50 had greater degrees of anxiety (P less than .001), depression (P less than .001), health-related worry (P less than .001), and felt less able to resist illness (P less than .001) than patients with higher health perception scores. Analysis of covariance was used to control for differences in physical health among groups of patients with varying health perceptions. These analyses revealed that patients with low health perceptions made more office visits (P = .002), more telephone calls to the physician (P = .01), and had more office charges (P = .05) than patients with higher scores. Physicians accurately predicted the patients' health perceptions in 49% of the cases. In 37%, they thought patients would score their health perceptions higher than they did; in 14% they thought patients would score their health perceptions lower. Health perceptions are an important factor contributing to the use of health care by primary care patients, regardless of the patient's actual physical health. Persons with low health perceptions account for approximately 5% of office visits, a clinically important fraction, especially when compared to the 9% of office visits for hypertension, the most common disease treated in the medical office.

Calf deep venous thrombosis. A wolf in sheep's clothing?

To determine the natural history of calf deep venous thrombosis (C-DVT), an analytic review of the 20 relevant English-language papers published since 1942 was performed. Remarkably little methodologically sound research on this subject was found. However, available evidence suggests that C-DVT propagates to the thigh in up to 20% of cases and that propagation invariably occurs before embolization. No fatal emboli were reported in patients presenting with isolated C-DVT. Traditional anticoagulation treatment with heparin sodium and warfarin sodium of symptomatic patients with C-DVT appears to prevent extension, embolization, and early recurrence. There is no convincing evidence that C-DVT leads to chronic venous insufficiency or whether the risks of anticoagulation exceed the risks of no treatment. As an option to anticoagulation, physicians may choose to follow patients with C-DVT with serial impedance plethysmography, treating only if there is evidence of proximal extension.

Do corticosteroids prevent postherpetic neuralgia? A review of the evidence

A short course of corticosteroids is frequently used in herpes zoster to prevent postherpetic neuralgia. To clarify the evidence behind this routine practice, we reviewed the three randomized controlled trials on this subject. Although in all three similar dosages of corticosteroids (40 mg to 60 mg prednisone daily for 2 to 4 weeks) were used, deficiencies in reported clinical characteristics of study subjects, the potential for bias in the ascertainment of pain duration, and the inability to exclude type II error make it impossible to determine whether or not this practice is effective. More research on this subject is needed, with greater attention to good study methodology.

Single-dose antibiotic treatment for uncomplicated urinary tract infections. Less for less?

Because of the many differences among studies of single-dose antimicrobial therapy for uncomplicated urinary tract infection in women, we reviewed the 14 randomized controlled trials on this subject. Twelve concluded that single-dose therapy was as effective as conventional multiple-dose therapy. Although the studies were carefully conducted, none both reported and ascertained in a blinded manner the incidence of adverse drug reactions. Also, no study included enough patients to prevent type II error. To circumvent the problem of having too few patients in each study, we used a rational strategy for pooling the data from the reviewed studies. Single-dose amoxicillin (3 g) was significantly less effective than conventional multidose therapy (69% vs 84%), while single-dose sulfamethoxazole-trimethoprim (two or three double-strength tablets) was indistinguishable from multidose, although there still were too few patients to exclude type II error. More research on this subject is needed with greater attention to sample size and blinded ascertainment of adverse reactions.

The limited spectrum of patients studied in exercise test research. Analyzing the tip of the iceberg

To investigate reasons for the wide variation in formal studies of sensitivity and specificity indexes for the diagnostic efficacy of the graded exercise test for angiographically defined coronary disease, data were collected on 205 consecutive exercise tests at two hospital-based exercise laboratories. For calculations of sensitivity and specificity, stress test data are usually analyzed with many exclusions for ineligibility, with equivocal results omitted, and only in patients undergoing angiography. Consequently, only 3% of patients who received the tests in this survey would have been included in a typical formal study of diagnostic efficacy. In the same way that the visible tip of an iceberg misrepresents its extent and depth, the patients assembled in studies of diagnostic tests may be a highly selected group that misrepresents the intended population.

Methodologic problems of exercise testing for coronary artery disease: groups, analysis and bias

To determine why exercise testing remains controversial as a diagnostic test for coronary artery disease, a methodologic review was undertaken of 33 studies comprising 7,501 patients who had undergone both exercise tests and coronary angiography. Of seven methodologic standards for research design, only one received general compliance: the requirement for an adequate variety of anatomic lesions. Less than half of the studies complied with any of the remaining six standards: adequate identification of the groups selected for study; adequate analysis for relevant chest pain syndromes; avoidance of a limited challenge group; and avoidance of work-up bias, diagnostic review bias and test review bias. Only one study met as many as five standards. These methodologic problems may explain the wide range of sensitivity (35 to 88 percent) and specificity (41 to 100 percent) found for exercise testing, because the variations could not be attributed to the usual explanations: definition of anatomic abnormality, stress test technique or definition of an abnormal test. Determining the true value of exercise testing requires methodologic improvements in patient selection, data collection and data analysis.