Peter B. Bach

Overview of the SEER-Medicare data: content, research applications, and generalizability to the United States elderly population.

Background. The Surveillance, Epidemiology and End Results (SEER)-Medicare–linked database combines clinical information from population-based cancer registries with claims information from the Medicare program. The use of this database to study cancer screening, treatment, outcomes, and costs has grown in recent years. Research Design. This paper provides an overview of the SEER-Medicare files for investigators interested in using these data for epidemiologic and health services research. The overview includes a description of the linkage of SEER and Medicare data and the files included as part of SEER-Medicare. The paper also describes the types of research projects that have been undertaken using the SEER-Medicare data. The overview concludes with a comparison of selected characteristics of elderly persons residing in the SEER areas to the US total aged. Results. The paper identifies a number of potential uses of the SEER-Medicare data. The comparison of the elderly population in SEER areas to the US total shows that in the SEER areas there are a lower percentage of white persons and individuals living in poverty, and a higher percentage of urban-dwellers than the US total. Elderly persons in the SEER regions also have higher rates of HMO enrollment and lower rates of cancer mortality. Conclusions. The SEER-Medicare data are a unique resource that can be used for a variety of health services research projects. Although there are some differences between the elderly residing in the SEER areas and the US total, the SEER-Medicare data offer a large population-based cohort that can be used to longitudinally track care for persons over the course of cancer diagnosis, treatment, and follow-up.

Racial Differences in the Treatment of Early-Stage Lung Cancer

BACKGROUND If discovered at an early stage, non-small-cell lung cancer is potentially curable by surgical resection. However, two disparities have been noted between black patients and white patients with this disease. Blacks are less likely to receive surgical treatment than whites, and they are likely to die sooner than whites. We undertook a population-based study to estimate the disparity in the rates of surgical treatment and to evaluate the extent to which this disparity is associated with differences in overall survival. METHODS We studied all black patients and white patients 65 years of age or older who were given a diagnosis of resectable non-small-cell lung cancer (stage I or II) between 1985 and 1993 and who resided in 1 of the 10 study areas of the Surveillance, Epidemiology, and End Results (SEER) program (10,984 patients). Data on the diagnosis, stage of disease, treatment, and demographic characteristics of the patients were obtained from the SEER data base. Information on coexisting illnesses, type of Medicare coverage, and survival was obtained from linked Medicare inpatient-discharge records. RESULTS The rate of surgery was 12.7 percentage points lower for black patients than for white patients (64.0 percent vs. 76.7 percent, P<0.001), and the five-year survival rate was also lower for blacks (26.4 percent vs. 34.1 percent, P<0.001). However, among the patients undergoing surgery, survival was similar for the two racial groups, as it was among those who did not undergo surgery. Furthermore, analyses in which adjustments were made for factors that are predictive of either candidacy for surgery or survival did not alter the influence of race on these outcomes. CONCLUSIONS Our analyses suggest that the lower survival rate among black patients with early-stage, non-small-cell lung cancer, as compared with white patients, is largely explained by the lower rate of surgical treatment among blacks. Efforts to increase the rate of surgical treatment for black patients appear to be a promising way of improving survival in this group.

Benefits and Harms of CT Screening for Lung Cancer: A Systematic Review

CONTEXT Lung cancer is the leading cause of cancer death. Most patients are diagnosed with advanced disease, resulting in a very low 5-year survival. Screening may reduce the risk of death from lung cancer. OBJECTIVE To conduct a systematic review of the evidence regarding the benefits and harms of lung cancer screening using low-dose computed tomography (LDCT). A multisociety collaborative initiative (involving the American Cancer Society, American College of Chest Physicians, American Society of Clinical Oncology, and National Comprehensive Cancer Network) was undertaken to create the foundation for development of an evidence-based clinical guideline. DATA SOURCES MEDLINE (Ovid: January 1996 to April 2012), EMBASE (Ovid: January 1996 to April 2012), and the Cochrane Library (April 2012). STUDY SELECTION Of 591 citations identified and reviewed, 8 randomized trials and 13 cohort studies of LDCT screening met criteria for inclusion. Primary outcomes were lung cancer mortality and all-cause mortality, and secondary outcomes included nodule detection, invasive procedures, follow-up tests, and smoking cessation. DATA EXTRACTION Critical appraisal using predefined criteria was conducted on individual studies and the overall body of evidence. Differences in data extracted by reviewers were adjudicated by consensus. RESULTS Three randomized studies provided evidence on the effect of LDCT screening on lung cancer mortality, of which the National Lung Screening Trial was the most informative, demonstrating that among 53,454 participants enrolled, screening resulted in significantly fewer lung cancer deaths (356 vs 443 deaths; lung cancer−specific mortality, 274 vs 309 events per 100,000 person-years for LDCT and control groups, respectively; relative risk, 0.80; 95% CI, 0.73-0.93; absolute risk reduction, 0.33%; P = .004). The other 2 smaller studies showed no such benefit. In terms of potential harms of LDCT screening, across all trials and cohorts, approximately 20% of individuals in each round of screening had positive results requiring some degree of follow-up, while approximately 1% had lung cancer. There was marked heterogeneity in this finding and in the frequency of follow-up investigations, biopsies, and percentage of surgical procedures performed in patients with benign lesions. Major complications in those with benign conditions were rare. CONCLUSION Low-dose computed tomography screening may benefit individuals at an increased risk for lung cancer, but uncertainty exists about the potential harms of screening and the generalizability of results.

The Influence of Hospital Volume on Survival after Resection for Lung Cancer

BACKGROUND Among patients who have undergone high-risk operations for cancer, postoperative mortality rates are often lower at hospitals where more of these procedures are performed. We undertook a population-based study to estimate the extent to which the number of procedures performed at a hospital (hospital volume) is associated with survival after resection for lung cancer. METHODS We studied patients 65 years old or older who received a diagnosis of stage I, II, or IIIA non-small-cell lung cancer between 1985 and 1996, resided in 1 of the 10 study areas covered by the Surveillance, Epidemiology, and End Results Program, and underwent surgery at a hospital that participates in the Nationwide Inpatient Sample (2118 patients and 76 hospitals). RESULTS The volume of procedures at the hospital was positively associated with the survival of patients (P<0.001). Five years after surgery, 44 percent of patients who underwent operations at the hospitals with the highest volume were alive, as compared with 33 percent of those who underwent operations at the hospitals with the lowest volume. Patients at the highest-volume hospitals also had lower rates of postoperative complications (20 percent vs. 44 percent) and lower 30-day mortality (3 percent vs. 6 percent) than those at the lowest-volume hospitals. CONCLUSIONS Patients who undergo resection for lung cancer at hospitals that perform large numbers of such procedures are likely to survive longer than patients who have such surgery at hospitals with a low volume of lung-resection procedures.

Limits on Medicare's Ability to Control Rising Spending on Cancer Drugs

During the past decade, the price of cancer drugs and the spending for cancer treatments by Medicare have increased dramatically. The author outlines the usual tools Medicare uses to control its spending on drugs and discusses the policies that make cancer drugs a special case and prohibit the regulation of their prices and utilization.

Management of Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Summary and Appraisal of Published Evidence

The primary aims of this paper are 1) to summarize and evaluate published data that address care of patients with acute exacerbations of chronic obstructive pulmonary disease [COPD] and 2) to improve the care that these patients receive by identifying efficacious and inefficacious treatment strategies. This paper provides the background evidence for the clinical practice guideline in this issue (see pages 595-599). A joint panel from the American College of PhysiciansAmerican Society of Internal Medicine (ACPASIM) and the American College of Chest Physicians (ACCP) assisted in the design, conduct, and development of this paper. The paper is based largely on the evidence report produced by the Evidence-Based Practice Center at Duke University, Durham, North Carolina, under contract with the Agency for Healthcare Research and Quality (AHRQ) (1). We review the health impact of COPD, define the entity acute exacerbation, and describe the methods we used to identify and grade the available data on care of this condition. In addition, we assess studies that evaluate diagnostic techniques, prognostic and risk stratification models, and an array of therapies and interventions. In the concluding sections, we review important elements of postexacerbation management, with special attention to follow-up care, and gradual titration of such therapeutic agents as oxygen and corticosteroids. Last, we comment on areas of management for patients with acute exacerbations that would most benefit from further research. In the United States, more than 16 million adults have COPD, a slow-progressing condition that usually becomes symptomatic in the fifth and sixth decades of life. As the U.S. population ages, the prevalence of this disease is expected to increase (2). Chronic obstructive pulmonary disease currently accounts for approximately 110 000 deaths per year, making it, after heart disease, cancer, and stroke, the fourth leading cause of death. Nonasthma COPD in the United States annually accounts for 16 367 000 office visits, 500 000 hospitalizations, and

Screening for Lung Cancer: Diagnosis and Management of Lung Cancer, 3rd ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

18 billion in direct health care costs (3, 4). The term COPD is used to describe a range of pathophysiologic entities characterized by airflow obstruction, including chronic bronchitis, emphysema, asthma, and bronchiectasis. In this paper and the accompanying guideline, we focus on the care of patients with the first two diagnoses. This approach is consistent with the National Heart, Lung, and Blood Institutes definition of COPD as an umbrella term used to encompass several more specific respiratory conditions, including chronic (obstructive) bronchitis and emphysema (5). In fact, separating these entities is difficult both when evaluating clinical studies and when practicing clinical medicine. Causes of COPD include smoking (85% to 90% of all cases), genetic factors (including 1 antitrypsin deficiency), passive smoking, occupational exposures, air pollution, and possibly hyperresponsive airways. Although precise distinctions between chronic bronchitis and emphysema are a subject of debate, tradition holds that chronic bronchitis is responsible for 85% of COPD. Patients with chronic bronchitis experience intermittent airway inflammation that leads to frequent, prolonged episodes of productive cough. In contrast, 15% of patients with COPD primarily have emphysema, a disease in which the infrastructure of alveoli and distal airspaces, and therefore the portion of the lung that provides elastic recoil, is destroyed. Both conditions predispose patients to a common constellation of symptoms and signs and a collection of impairments in respiratory function. Spirometric testing is used to confirm the diagnosis of COPD. Typical abnormalities include a decrease in FEV1 and a decrease in the ratio of FEV1 to FVC. Other abnormalities include an increased residual volume and total lung capacity and a limited and incomplete response of FEV1 to bronchodilators (incomplete reversibility). Diffusing capacity for carbon monoxide is often diminished in emphysema, and response to bronchodilators can be seen in patients with concomitant asthma. Several staging systems are available for patients with stable COPD. The staging systems of both the European Respiratory Society and the American Thoracic Society use FEV1 as the sole staging characteristic because it is most closely correlated with mortality and frequency of acute exacerbation. The British Thoracic Society staging system also includes clinical features of a patients cough, sputum, dyspnea, and lung sounds (Table 1). Table 1. Available Staging Systems for Chronic Obstructive Pulmonary Disease In evaluating the published literature and in developing practice guidelines, we have attempted to adhere to a generally accepted and useful concept of an acute exacerbation or flare of COPD. However, many definitions exist, many authors use substantively different criteria, and many studies describe their inclusion criteria poorly. In general, most published definitions involve some combination of three clinical findings: worsening of dyspnea, increase in sputum purulence, and increase in sputum volume. Unlike the staging systems for stable COPD, there are no standardized, validated grading systems for severity of an acute exacerbation. Probably the most commonly used system is that developed by Anthonisen and colleagues (6). In this system, patients with type 1 (severe) exacerbations have all three of the main clinical findings and those with type 2 (moderate) exacerbations have two of the three. Patients with type 3 (mild) exacerbations have at least one of these clinical findings and at least one of the following clinical criteria: an upper respiratory infection in the past 5 days, fever without other apparent cause, increased wheezing, increased cough, or increase in respiratory rate or heart rate by 20% above baseline (Table 1). Clinicians should be aware that other conditions, such as heart failure and pulmonary embolism, can mimic an acute exacerbation. Tracheobronchial infections are believed to be a common inciting cause of acute exacerbations of COPD. However, controversy surrounds the nature of the infectious agent as well as its exact role. Sputum obtained from patients with mild to moderately severe chronic bronchitis routinely culture a variety of bacteria, including Haemophilus influenzae (22%), Pseudomonas aeruginosa (15%), Streptococcus pneumoniae (10%), and Moraxella catarrhalis (9%) (10). Nonpathogenic bacteria, such as H. parainfluenzae, account for up to one third of all isolates. Also, certain groups of patients, such as those living in nursing homes, those recently treated with antibiotics, and those admitted to intensive care units, are more likely to be colonized with resistant organisms, such as Pseudomonas species. The role of these colonizers in the pathogenesis of acute exacerbation remains unclear, and their presence makes interpretation of any sputum culture difficult. Some investigators have also proposed that Mycoplasma pneumoniae or Chlamydia pneumoniae may precipitate between 1% to 10% of exacerbations (11-13). Others have pointed out that the presence of eosinophilic inflammation in bronchial biopsy specimens from patients with exacerbations may indicate that viruses (notably rhinovirus) play an important role (14, 15). Acute exacerbations are clearly associated with environmental exposures as well. Significant correlations between levels of respirable particles (diameter < 10 m) and ozone have been linked to hospital admission rates (16). Finally, severe exacerbations may be precipitated by other serious clinical conditions, such as heart failure, nonpulmonary infections, pulmonary embolism, and pneumothorax (17). The outcomes of COPD exacerbations are similarly heterogeneous. Although nearly 50% of exacerbations are not reported to physicians (18, 19), exacerbations requiring hospitalization are associated with an inpatient mortality rate of 3% to 4% (20). Mortality rates are substantially higher among patients who require treatment in an intensive care unit (11% to 24% in-hospital and 43% to 46% by 1 year) (17, 21-24). After an acute exacerbation, most patients are expected to experience at least a temporary decrease in functional status and quality of life (19, 25, 26), and 50% of those hospitalized for the condition are expected to be readmitted at least once in the ensuing 6 months (17, 27). 1.0 Methods Identification of Topics for Literature Search Topics to be covered in this paper and in the practice guideline were determined through a consensus process that involved both the ACPASIM/ACCP expert panel and the technical advisory panel of the Evidence-Based Practice Center at Duke University. The topic list was generated to address three questions: 1) What information is available to aid clinicians in predicting the clinical course of a patient with an acute exacerbation? 2) What information is available about the utility of diagnostic tests used to evaluate patients with symptoms of acute exacerbation? 3) What information is available to help guide clinicians in using available therapies and interventions? We did not consider care of patients with chronic, stable COPD; experimental therapies that are not widely available; or invasive mechanical ventilation. Search Strategy We gathered information through systematic searches and ongoing surveillance of MEDLINE (1966 to 2000, week 5), EMBASE (1974 to 2000, week 18), HealthStar (1975 to June 2000), and the Cochrane Controlled Trials Register (2000, Issue 1). Search strategies included the index terms and textwords chronic obstructive pulmonary disease and acute exacerbation and specific terms relating to interventions and outcomes. Variations on several search strategies were tested in order to locate the greatest number of relevant articles. The abstracts of relevant articles were reviewed against predetermined criteria and appropriate articles were r

Adjuvant Chemotherapy Use for Medicare Beneficiaries With Stage II Colon Cancer

BACKGROUND Lung cancer is by far the major cause of cancer deaths largely because in the majority of patients it is at an advanced stage at the time it is discovered, when curative treatment is no longer feasible. This article examines the data regarding the ability of screening to decrease the number of lung cancer deaths. METHODS A systematic review was conducted of controlled studies that address the effectiveness of methods of screening for lung cancer. RESULTS Several large randomized controlled trials (RCTs), including a recent one, have demonstrated that screening for lung cancer using a chest radiograph does not reduce the number of deaths from lung cancer. One large RCT involving low-dose CT (LDCT) screening demonstrated a significant reduction in lung cancer deaths, with few harms to individuals at elevated risk when done in the context of a structured program of selection, screening, evaluation, and management of the relatively high number of benign abnormalities. Whether other RCTs involving LDCT screening are consistent is unclear because data are limited or not yet mature. CONCLUSIONS Screening is a complex interplay of selection (a population with sufficient risk and few serious comorbidities), the value of the screening test, the interval between screening tests, the availability of effective treatment, the risk of complications or harms as a result of screening, and the degree with which the screened individuals comply with screening and treatment recommendations. Screening with LDCT of appropriate individuals in the context of a structured process is associated with a significant reduction in the number of lung cancer deaths in the screened population. Given the complex interplay of factors inherent in screening, many questions remain on how to effectively implement screening on a broader scale.

A Comparison of Electrophysiologically Guided Antiarrhythmic Drug Therapy with Beta-Blocker Therapy in Patients with Symptomatic, Sustained Ventricular Tachyarrhythmias

PURPOSE Clinical trials have not demonstrated that adjuvant chemotherapy improves survival for patients with resected stage II colon cancer. Nevertheless, patients may receive this treatment despite its uncertain benefit. The objective of this study was to determine the extent to which adjuvant chemotherapy is used for patients with stage II colon cancer. PATIENTS AND METHODS Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified 3,151 patients aged 65 to 75 with resected stage II colon cancer and no adverse prognostic features. The primary outcome was chemotherapy use within 3 months of surgery ascertained from claims submitted to Medicare. Relationships between patient characteristics and adjuvant chemotherapy use were measured and their significance was assessed using multivariable logistic regression. Survival for treated and untreated patients was compared using a Cox model. RESULTS Twenty-seven percent of patients received chemotherapy during the 3 postoperative months. Younger age at diagnosis, white race, unfavorable tumor grade, and low comorbidity were each associated with a greater likelihood of receiving treatment. Sex, the number of examined lymph nodes in the tumor specimen, the urgency of the surgical admission, and median income was each unrelated to treatment. Five-year survival was 75% for untreated patients and 78% for treated patients. After adjusting for known between-group differences, the hazard ratio for survival associated with adjuvant treatment was 0.91 (95% confidence interval, 0.77 to 1.09). CONCLUSION A substantial percentage of Medicare beneficiaries with resected stage II colon cancer receive adjuvant chemotherapy despite its uncertain benefit.

Who Gets Adjuvant Treatment for Stage II and III Rectal Cancer? Insight From Surveillance, Epidemiology, and End Results–Medicare

BACKGROUND Antiarrhythmic drug therapy guided by invasive electrophysiologic testing is now widely used in patients with symptomatic, sustained ventricular tachyarrhythmias. METHODS We conducted a prospective, randomized trial in 170 patients to investigate whether this approach would improve long-term outcome. Patients whose arrhythmia was inducible by programmed electrical stimulation were assigned to treatment with electrophysiologically guided drug therapy based on serial testing (61 patients) or with metoprolol (54 patients). Electrophysiologically guided therapy consisted of serial testing of antiarrhythmic agents to identify the first one that rendered the arrhythmia noninducible. The 55 patients whose arrhythmia was noninducible during the initial electrophysiologic test were also treated with metoprolol. RESULTS During a mean (+/- SD) follow-up period of 23 +/- 17 months, recurrent, nonfatal arrhythmia occurred in 44 patients and sudden death due to cardiac factors in 27. The incidence of symptomatic arrhythmia and sudden death combined was virtually the same in the two groups with inducible arrhythmia after two years of observation (electrophysiologically guided therapy vs. metoprolol therapy, 46 percent vs. 48 percent). The outcome was more favorable in the patients with noninducible arrhythmia at base line (75 percent had neither adverse event) than in those with inducible arrhythmia who were assigned to metoprolol therapy (P = 0.009 by log-rank test). Only 6 of the 29 patients (21 percent) with inducible arrhythmia that became noninducible during drug therapy had recurrent arrhythmia or sudden death, as compared with 21 of the 32 patients (66 percent) with arrhythmia that continued to be inducible (P less than 0.001). A multivariate regression analysis identified continued inducibility of the arrhythmia as an independent predictor of recurrent arrhythmia or sudden death (relative risk, 7.3; 95 percent confidence interval, 2.3 to 23.2; P less than 0.001). CONCLUSIONS As compared with metoprolol therapy, electrophysiologically guided antiarrhythmic drug therapy did not improve the overall outcome of patients with sustained ventricular tachyarrhythmias. However, effective suppression of inducible arrhythmia by antiarrhythmic drugs was associated with a better outcome than was lack of suppression.