Seema S. Sonnad

Comorbidities and quality of life in patients with interferon-refractory chronic hepatitis C

OBJECTIVES:Patients with chronic hepatitis C (HCV) consistently report a reduction in multiple domains of health-related quality of life (HRQOL) that does not correlate with liver disease severity. This may in part be due to the use of insensitive HRQOL instruments or extrahepatic factors that independently influence HRQOL. We hypothesized that a past history of substance abuse or active medical and psychiatric comorbidities would correlate with HRQOL scores.METHODS:In 107 patients who had failed previous interferon therapy, HRQOL was measured by using the modified SF-36, a disease-specific instrument, and the Health Utilities Index (HUI) Mark III, a generic instrument.RESULTS:Multiple SF-36 subscale and summary scores as well as the HUI Mark III attributes of emotion and pain were significantly reduced in the study population compared with healthy controls (p < 0.001). Serum alanine aminotransferase and HCV RNA levels, HCV genotype, liver histology, and HCV risk factors as well as demographic variables did not correlate with modified SF-36 and HUI scores. In addition, a history of alcohol abuse or dependency and intravenous drug use or dependency, identified in 52 and 51% of participants, respectively, did not correlate with HRQOL scores. However, the presence of one or more active medical comorbidities, defined as a chronic medical condition requiring treatment and monitoring, was significantly associated with both the modified SF-36 scores and HUI attribute deficits (p < 0.001). In particular, painful medical comorbidities or depressed mood requiring treatment were significantly associated with modified SF-36 scores and with HUI attribute deficits and utility scores (p < 0.001).CONCLUSIONS:Active medical and psychiatric comorbidities may account for some of the reduction and variability in HRQOL scores in patients with chronic HCV who have failed previous interferon therapy. Future studies that control for the presence of active comorbidities in large groups of treatment naïve patients with varying severity of chronic HCV are needed to confirm these findings.

Managed care, medical technology, and health care cost growth : A review of the evidence

Although managed care plans reduce health care expenditures at any point in time, less is known about whether such plans control health care cost growth. Because use of new medical technology is an important determinant of cost growth, the impact of managed care on utilization of medical technology will largely determine whether managed care can reduce expenditure growth to sustainable levels. This article reviews the literature relating medical technology to cost growth and the literature examining the impact of managed care on either cost growth or on the diffusion of medical technology. Studies that examine plan-level data often reach different conclusions than studies that examine market-level data. The evidence suggests that managed care, as currently practiced, may reduce the rate of cost growth. However, managed care is unlikely to prevent the share of gross domestic product spent on health care from rising unless the cost-increasing nature of new technology changes.

Effect of postoperative atrial fibrillation on length of stay after cardiac surgery (the postoperative atrial fibrillation in cardiac surgery study [PACS2])

Atrial fibrillation (AF) after cardiac surgery is thought to increase length of stay (LOS). A clinical pathway focused on the management of postoperative AF, including prophylaxis with beta blockers, was implemented to assess the effect of AF on LOS after cardiac surgery. Data were obtained on consecutive cardiac surgery patients in preoperative normal sinus rhythm, no prior history of AF, and no chronic antiarrhythmic therapy from January to May 1995 (control) and November 1996 to June 1997 (pathway). Statistical analysis was performed to assess the effect of postoperative AF on the LOS, clinical outcomes, and cost after cardiac surgery. Despite the clinical pathway, the LOS (7 days for both periods; p = 0.12) and incidence of AF (28.9% vs 28.4%; p = 0.92) remained unchanged. Unadjusted direct costs were 15% higher in the pathway period (p <0.001). Increased rates of beta-blocker therapy had a marginal effect on the incidence of postoperative AF, except in the group who only underwent primary coronary artery bypass graft surgery (31.2% vs 25.3%; p = 0.31). Multivariate analysis revealed that AF contributed only 1 to 1.5 days to the LOS. Thus, this investigation represents the most recent analysis of the effects of postoperative AF on LOS, clinical outcomes, and cost after cardiac surgery. Unlike prior studies, the impact of postoperative AF is less prominent in the current era of cardiac surgical care regardless of the presence of a clinical pathway addressing AF.

Doctor-patient communication in surgery: attitudes and expectations of general surgery patients about the involvement and education of surgical residents

BACKGROUNDnEducation is a major function of academic medical centers. At these teaching institutions residents provide a substantial amount of care on medical and surgical services. The attitudes of patients about the training of surgical residents and the impact of residents on patients perceptions of care in a surgical setting are unknown.nnnSTUDY DESIGNnPatients admitted to the gastrointestinal surgery service completed a 30-item survey designed for this study. Patients included in the study underwent operations and had a postoperative inpatient hospital stay. We analyzed patients answers to determine frequency and correlations among answers.nnnRESULTSnTwo hundred patients participated in the study during a 7-month period between July 1999 and January 2000. A majority of patients were comfortable having residents involved in their care (86%) and felt it was important to help educate future surgeons (91%). Most did not feel inconvenienced by being at a teaching hospital (71%) and felt they received extra attention there (74%). Patients were more willing to participate in resident education if they expected to have several physicians involved in their care, felt that they received extra attention, or if the teaching atmosphere did not inconvenience them. Despite the stated willingness of patients to help with surgical resident education, 32% answered that they would not want residents doing any of their operation.nnnCONCLUSIONSnSurgical resident education is well received and considered important by patients. Patient orientation to the resident education process is vital to patients perceptions of care and may render patients more willing to participate in educational activities.

Accuracy of MR imaging in the work-up of suspicious breast lesions: A diagnostic meta-analysis

RATIONALE AND OBJECTIVESnThe authors performed a systematic, critical review of the literature on magnetic resonance (MR) imaging for primary breast cancer detection in patients with suspicious breast lesions, analyzed MR test performance in the articles meeting study criteria, and used this information to examine the cost-effectiveness of preoperative MR imaging.nnnMATERIALS AND METHODSnA structured, predefined MEDLINE search was conducted to identify potentially relevant, peer-reviewed, English-language references from January 1996 through August 1997 on the diagnostic accuracy of breast MR imaging. This information was supplemented by manually searching bibliographies of the retrieved articles for additional potentially relevant references. All studies were independently abstracted by two reviewers using a prospectively designed worksheet. Abstraction results were analyzed with the summary receiver operating characteristic (ROC) method.nnnRESULTSnOf 41 identified studies, 16 met the inclusion criteria. These studies reported sensitivities ranging from 63% to 100% and specificities ranging from 21% to 100%. Maximum joint sensitivity and specificity of the summary ROC curve was 89% (95% confidence interval [CI]: 82%, 93%). At a sensitivity of 95%, specificity was 67%. When test performance values were applied to a previous cost-effectiveness analysis, the cost-effectiveness of preoperative MR imaging relative to that of excisional biopsy was confirmed, but its cost-effectiveness relative to that of needle core biopsy varied widely.nnnCONCLUSIONnFor MR imaging to be a cost-effective alternative to excisional biopsy for diagnosis of suspicious breast lesions, its diagnostic test performance must be equal to or better than the best results in recently published studies.

Implementation of the ACC/AHA Guidelines for Preoperative Cardiac Risk Assessment in a General Medicine Preoperative Clinic: Improving Efficiency and Preserving Outcomes

Background: The American College of Cardiology/American Heart Association (ACC/AHA) publishes recommendations for cardiac assessment of patients undergoing noncardiac surgery with the intent of promoting evidence-based, efficient preoperative screening and management. We sought to study the impact of guideline implementation for cardiac risk assessment in a general internal medicine preoperative clinic. Methods: The study was an observational cohort study of consecutive patients being evaluated in an outpatient preoperative evaluation clinic before and after implementation of the ACC/AHA guideline. Data was gathered by retrospective abstraction of hospital and clinic charts using standard definitions. 299 patients were reviewed prior to guideline implementation and their care compared to 339 consecutive patients after the guideline was implemented in the clinic. Results: Guideline implementation led to a reduction in exercise stress testing (30.8% before, 16.2% after; p < 0.001) and hospital length of stay (6.5 days before, 5.6 days after; p = 0.055). β-Blocker therapy increased after the intervention (15.7% before; 34.5% after; p < 0.001) and preoperative test appropriateness improved (86% before to 94.1% after; p < 0.001). Conclusions: Implementation of the ACC/AHA guidelines for cardiac risk assessment prior to noncardiac surgery in an internal medicine preoperative assessment clinic led to a more appropriate use of preoperative stress testing and β-blocker therapy while preserving a low rate of cardiac complications.

Polymerase Chain Reaction for the Diagnosis of HIV Infection in Adults: A Meta-Analysis with Recommendations for Clinical Practice and Study Design

Polymerase chain reaction (PCR) is a gene amplification technique that has found widespread use in medicine and molecular biology. The PCR assay was developed in 1985 [1, 2], and one of its earliest and most important clinical applications has been the diagnosis of human immunodeficiency virus (HIV) infection [3-9]. The PCR assay received attention as a diagnostic test for HIV infection in part because numerous reports suggested that months to years might elapse between infection with HIV and the development of HIV antibodies that could be detected by enzyme immunoassay and Western blot analysis [10, 11]. Because PCR directly amplifies proviral HIV DNA and does not depend on HIV antibody formation, it is a potentially attractive alternative to conventional antibody tests. However, the clinical role of PCR in the diagnosis of HIV infection remains uncertain because subsequent studies [12, 13] have not confirmed the occurrence of long window periods between infection and the development of antibodies. Considerable controversy remains about the diagnostic accuracy of PCR. Some studies report that the test has perfect sensitivity and specificity, but others report high false-positive and false-negative rates. An understanding of the diagnostic performance of PCR for HIV infection is essential in determining the appropriate role of PCR in the clinical diagnosis of such infection. However, evaluation of the performance of PCR poses difficult methodologic challenges. To evaluate the sensitivity and specificity of PCR, investigators must ascertain whether study participants are infected with HIV. Typically, a new test is compared with a superior reference (or gold standard) test, but PCR is an example of a class of diagnostic technologies (including, for example, genetic screening tests) that have the potential to outperform and displace existing tests. At least in certain clinical circumstances, PCR may be more sensitive or more specific than the current reference tests (enzyme immunoassay followed by confirmatory Western blot analysis). The lack of an appropriate reference test substantially complicates evaluation. A successful approach to the evaluation of such technologies would be broadly useful. We sought to 1) assess the validity and reliability of the scientific evidence on the diagnostic accuracy of PCR; 2) characterize the sensitivity and specificity of PCR on the basis of a formal analysis of the available studies; 3) develop recommendations for the clinical use of PCR in persons with suspected HIV infection; and 4) develop recommendations for the design of future studies of the diagnostic accuracy of PCR. In pursuing our third objective, we paid particular attention to whether PCR technology has improved enough to play a broader clinical role in the diagnosis of HIV infection. We did not evaluate the use of PCR for the quantification of viral load [14] or for the prediction or assessment of response to antiviral therapy [15]. We postulated that more recent studies, because they would reflect advances in PCR technology, would report higher sensitivities and specificities. We also expected that the most methodologically rigorous studies would report lower sensitivities and specificities than other studies and that studies published as full articles would report higher sensitivities and specificities than studies published only as abstracts because of publication bias (the results of which would be that studies reporting high sensitivity and specificity would be published more frequently than studies reporting poor test performance). Methods We did a meta-analysis of the published English-language literature to examine the relation between study population, study characteristics, technical aspects of the assay, and measured test performance. We used statistical techniques to fit a summary receiver-operating characteristic (ROC) curve that characterizes the results of multiple studies [16]. An ROC curve represents the tradeoff between sensitivity and specificity for a diagnostic test. It can be used to compare diagnostic tests by assessing the degree to which differences in test sensitivity and specificity result from the use of different cut-off points for abnormality rather than from actual differences in test performance [17]. Typically, an ROC curve is developed from a single study by varying the cut-off point for an abnormal test. In our study, we developed summary ROC curves on the basis of an analysis of multiple studies. Although the method for developing a summary ROC curve differs from the method for developing an ROC curve from a single study, the summary ROC curve also estimates the tradeoff between sensitivity and specificity for a diagnostic test. Study Identification An investigator and a professional librarian with extensive experience in medical literature searches independently developed search strategies to identify studies of PCR for the diagnosis of HIV infection that had been published through the middle of 1994 (Appendix). We also manually searched the bibliographies of retrieved articles and conference proceedings. We wrote to the authors of studies that were published only as abstracts and requested information about study design and updated data on PCR performance. Study Selection Two investigators independently examined all titles, abstracts, and full articles identified in the search. We included studies if 1) PCR was done on peripheral blood mononuclear cells; 2) DNA [as opposed to RNA] was amplified; 3) study participants were older than 16 years of age; 4) more than 10 participants were enrolled; and 5) primary data sufficient for the determination of both sensitivity and specificity were reported. We excluded studies with fewer than 10 participants because we believed such studies would provide unreliable estimates. We also excluded studies that determined only sensitivity or specificity, because calculation of each is needed to determine a point on the ROC curve. Disagreements were resolved by re-review and discussion. Data Abstraction Two investigators independently abstracted data from each study, including the characteristics and risk behaviors of the study sample; the technical details of the assay, including the use of heparin [18]; the reference test used (for example, Western blot analysis or viral culture); the criteria used to interpret results of both PCR and the reference test; and the data needed to calculate the sensitivity, specificity, false-positive rate, and false-negative rate of PCR. Disagreements were resolved by re-review and discussion. Calculation of Sensitivity and Specificity for Polymerase Chain Reaction We abstracted primary data on the performance of PCR into a 3 3 table in which all participants (or test results) were classified as PCR-positive, PCR-negative, or PCR-indeterminate and as reference test-positive, reference test-negative, or reference test-indeterminate. We used the authors criteria for PCR-positive, -negative, and -indeterminate test results (for example, the number of primers that had to be detected for a PCR test result to be positive) when they were stated. In the few instances in which these criteria were not stated, we defined a positive test result (in terms of the number of primer pairs detected) to maximize both sensitivity and specificity, if possible, or to maximize sensitivity if doing so did not substantially decrease specificity. We examined whether differences in these criteria affected test performance. We calculated both upper and lower estimates of PCR sensitivity and specificity. We calculated the upper estimate by excluding results that were PCR indeterminate (thereby overestimating sensitivity and specificity), and we calculated the lower estimate by considering reference-test-positive, PCR-indeterminate results to be false-negative results and by considering reference test-negative, PCR-indeterminate results to be false-positive results (thereby underestimating sensitivity and specificity). For the lower estimate, we also considered PCR test results to be false-positive if, after repeated PCR and antibody tests, the results remained PCR-positive and antibody test-negative throughout the follow-up period [8, 19-23]. Excluding these few discordant samples did not produce a statistically significant change in our lower-bound estimate. When possible, PCR performance was evaluated on the basis of the number of study participants rather than the number of tests conducted (some participants were tested more than once). This was done because repeated samples in the same individual person are not independent, and the use of multiple test results from an individual person may therefore spuriously inflate or deflate estimated sensitivity and specificity. Approximately 2% of the samples included in our analysis were repeated samples from individual persons that we could not exclude. Because we calculated sensitivity and specificity by using prospectively defined criteria for the patients true disease state, the sensitivity and specificity we report for a study sometimes differ from those reported by the original authors. We calculated 95% CIs for individual study estimates of sensitivity and specificity (Figure 1) by using normal or Poisson approximations to the binomial distribution [24], as appropriate [25]. Figure 1. Calculated sensitivity and false-positive rate (1.0 specificity) for included studies published before 1992. Assessment of Study Design To assess the reliability of the evidence for the diagnostic accuracy of PCR for HIV infection, two investigators independently assessed the design of the studies by using prospectively developed criteria (Table 1). To develop these criteria, we modified a previously developed assessment framework for diagnostic tests [26-28]. Investigators were blinded to the study title, study results, study authors, the name of the journal in which the study results were published, and t

Aortic Intimal Tears: Detection with Spiral Computed Tomography

PURPOSEnTo determine the frequency, locations, and sizes of aortic intimal tears detected using spiral computed tomography (CT).nnnMETHODSnCT scans (26 single detector and 26 multidetector studies) from 52 patients with an unoperated aortic dissection and a patent false lumen were evaluated on a workstation. The number, location, and size of aortic tears were recorded and compared between the following groups: acute and chronic dissection, type A and type B, and single detector and multidetector studies.nnnRESULTSnIn 52 patients, 129 tears were identified (mean 2.48 per patient, median 2, range 1-7). There were no significant differences in the number or size of tears between the acute and chronic, the type A and type B, or the single detector and multidetector groups (p>0.05). The most common locations for tears were the descending aorta (57, 44%) and the juxtarenal region (26, 20%). Within the type B category, there was no significant difference in tear locations between the acute and chronic groups (p>0.05). The majority of tears (88, 68%) were < or =1 cm in each dimension. Tears in the thoracic aorta were significantly larger than abdominal aortic tears (p<0.05).nnnCONCLUSIONSnAll patients with an aortic dissection and a patent false lumen demonstrated one or more aortic intimal tears using spiral CT. Although most tears were small (</=1 cm), they were usually easily visualized.

Ligation versus anticoagulation: treatment of above-knee superficial thrombophlebitis not involving the deep venous system.

Historically, superficial thrombophlebitis has been considered a benign disease requiring only conservative management with compression support, nonsteroidal antiinflammatory medications, and lower extremity elevation. During the past 40 years, several studies and case reports have established the clinical significance concerning above-knee superficial thrombophlebitis (AKSTP), up to the saphenofemoral junction, but not invading into the deep venous system. AK-STP may lead to pulmonary embolism (PE), either secondary to extension into the deep venous system, or directly without deep venous thrombosis. A medical approach using anticoagulant therapy appears effective in reducing the incidence of PE when used for AK-STP with deep venous system involvement. Controversy remains regarding the best approach to treating AK-STP without deep venous system involvement. Surgery has been one option for treating AK-STP without involvement of the deep venous system. Operative interventions range from ligation of the saphenofemoral venous junction to ligation and stripping of the phlebitic veins. Surgical treatment modalities halt the progression of thrombus into the deep venous system through the saphenofemoral junction and reduce the incidence of PE. But many clinicians continue to use conservative therapies or select medical therapy with anticoagulants as the sole treatment for AK-STP. Most patients are not evaluated by surgeons nor are they presented with a surgical option. Although anticoagulation alone reduces the incidence of PE when compared with conservative therapy, few studies exist comparing treatment outcomes of surgical treatment versus medical therapy with anticoagulation for AK-STP. This article reviews the currently available literature regarding surgical and medical management of AK-STP not involving the deep venous system.

Providing health information to women. The role of magazines.

OBJECTIVESnWe were interested in health coverage in womens magazines in the United States and how it compared with articles in medical journals, womens health interests, and womens greatest health risks.nnnMETHODSnWe examined 12 issues of Good Housekeeping (GH) and Womans Day (WD) and 63 issues of the New England Journal of Medicine (NEJM) and the Journal of the American Medical Association (JAMA). We tallied the most common health questions of women presenting to the University of Michigans Womens Health Resource Center (WHRC) during the same period.nnnRESULTSnLess than a fifth of the magazine articles dealt with health-related topics. Of those, a third dealt with diet, with the majority emphasizing weight loss rather than eating for optimal health. Few of the articles cited research studies, and even fewer included the name of the journal in which the study was published. In JAMA and NEJM, less than one-fifth of original research studies dealt with womens health topics, most commonly pregnancy-related issues, hormone replacement therapy, breast and ovarian cancer, and birth defects. At the same time, the most common requests for information at the WHRC related to pregnancy, fertility, reproductive health, and cancer.nnnCONCLUSIONnThe topics addressed in womens magazines do not appear to coincide with the topics addressed in leading medical journals, nor with womens primary health concerns or greatest health risks. Information from womens magazines may be leading women to focus on aspects of health and health care that will not optimize risk reduction.