Therese A. Stukel

Hospital Volume and Late Survival After Cancer Surgery

Context:Although hospital procedure volume is clearly related to operative mortality with many cancer procedures, its effect on late survival is not well characterized. Objective:To examine relationships between hospital volume and late survival after different types of cancer resections. Design:Using the national Surveillance Epidemiology and End Results (SEER)-Medicare linked database (1992–2002), we identified all patients undergoing major resections for lung, esophageal, gastric, pancreatic, colon, and bladder cancer (n = 64,047). Relationships between hospital volume and survival were assessed using Cox proportional hazards models, adjusting for patient characteristics and use of adjuvant radiation and chemotherapy. Study Participants: U.S. Medicare patients residing in SEER regions. Main Outcome Measures: 5-year survival. Results:Although there were statistically significant relationships between hospital volume and 5-year survival with all 6 cancer types, the relative importance of volume varied markedly. Absolute differences in 5-year survival probabilities rates between low-volume hospitals (LVHs) and high-volume hospitals (HVHs) ranged from 17% for esophageal cancer resection (17% vs. 34%, respectively) to only 3% for colon cancer resection (45% vs. 48%). Absolute differences in 5-year survival between LVHs and HVHs fell between these ranges for lung (6%), gastric (6%), pancreatic (5%), and bladder cancer (4%). Volume-related differences in late survival could not be attributed to differences in rates of adjuvant therapy. Conclusions:Along with lower operative mortality, HVHs have better late survival rates with selected cancer resections than their lower-volume counterparts. Mechanisms underlying their better outcomes and thus opportunities for improvement remain to be identified.

Cyclo-oxygenase-2 inhibitors versus non-selective non-steroidal anti-inflammatory drugs and congestive heart failure outcomes in elderly patients: a population-based cohort study

BACKGROUND Non-selective, non-steroidal anti-inflammatory drugs (NSAIDs) are associated with an increased risk of congestive heart failure, but little is known about the cardiovascular effects of a newer group of NSAIDS called selective cyclo-oxygenase (COX)-2 inhibitors. We aimed to compare rates of admission for congestive heart failure in elderly patients who were newly dispensed COX-2 inhibitors or non-selective NSAIDs. METHODS In this population-based retrospective cohort study we identified NSAID-naive individuals aged 66 years or older, who were started on rofecoxib (n=14,583), celecoxib (n=18,908), and non-selective NSAIDs (n=5,391), and randomly selected non-NSAID users as controls (n=100,000). FINDINGS Relative to non-NSAID users, patients on rofecoxib and non-selective NSAIDS had an increased risk of admission for congestive heart failure (adjusted rate ratio 1.8, 95% CI 1.5-2.2, and 1.4, 1.0-1.9, respectively), but not celecoxib (1.0, 0.8-1.3). Compared with celecoxib users, admission was significantly more likely in users of non-selective NSAIDs (1.4, 1.0-1.9) and rofecoxib (1.8, 1.4-2.4). Risk of admission for rofecoxib users was higher than that for non-selective NSAID users (1.5, 1.1-2.1). Of patients with no admission in the past 3 years, only rofecoxib users were at increased risk of subsequent admission relative to controls (1.8, 1.4-2.3). INTERPRETATION These findings suggest a higher risk of admission for congestive heart failure in users of rofecoxib and non-selective NSAIDs, but not celecoxib, relative to non-NSAID controls.

Bleeding and Perforation After Outpatient Colonoscopy and Their Risk Factors in Usual Clinical Practice

BACKGROUND & AIMS The most widely quoted complication rates for colonoscopy are from case series performed by expert endoscopists. Our objectives were to evaluate the rates of bleeding, perforation, and death associated with outpatient colonoscopy and their risk factors in a population-based study. METHODS We identified all individuals 50 to 75 years old who underwent an outpatient colonoscopy during April 1, 2002, to March 31, 2003, in British Columbia, Alberta, Ontario, and Nova Scotia, Canada. Using administrative data, we identified all individuals who were admitted to hospital with bleeding or perforation within 30 days following the colonoscopy in each province. We calculated the pooled rates of bleeding and perforation from the 4 provinces. In Ontario, we abstracted the hospital charts of all deaths that occurred within 30 days following the procedure. We used generalized estimating equations models to evaluate factors associated with bleeding and perforation. RESULTS We identified 97,091 persons who had an outpatient colonoscopy. The pooled rates of colonoscopy-related bleeding and perforation were 1.64/1000 and 0.85/1000, respectively. The death rate was 0.074/1000 or approximately 1/14,000. Older age, male sex, having a polypectomy, and having the colonoscopy performed by a low-volume endoscopist were associated with increased odds of bleeding or perforation. CONCLUSIONS Although colonoscopy has established benefits for the detection of colorectal cancer and adenomatous polyps, the procedure is associated with risks of serious complications, including death. Older age, male sex, having a polypectomy, and having the procedure done by a low-volume endoscopist were independently associated with colonoscopy-related bleeding and perforation.

Hospital volume, length of stay, and readmission rates in high-risk surgery.

Objective Aimed at reducing surgical deaths, several recent initiatives have attempted to establish volume-based referral strategies in high-risk surgery. Although payers are leading the most visible of these efforts, it is unknown whether volume standards will also reduce resource use. Methods We studied postoperative length of stay and 30-day readmission rate after 14 cardiovascular and cancer procedures using the 1994-1999 national Medicare database (total n = 2.5 million). We used regression techniques to examine the relationship between length of stay, 30-day readmission, and hospital volume, adjusting for age, gender, race, comorbidity score, admission acuity, and mean social security income. Results Mean postoperative length of stay ranged from 3.4 days (carotid endarterectomy) to 19.6 days (esophagectomy). There was no consistent relationship between volume and mean length of stay; it significantly increased across volume strata for 7 of the 14 procedures and significantly decreased across volume strata for the other 7. Mean length of stay at very-low-volume and very-high-volume hospitals differed by more than 1 day for 6 procedures. Of these, the mean length of stay was shorter in high-volume hospitals for 3 procedures (pancreatic resection, esophagectomy, cystectomy), but longer for other procedures (aortic and mitral valve replacement, gastrectomy). The 30-day readmission rate also varied widely by procedure, ranging from 9.9% (nephrectomy) to 22.2% (mitral valve replacement). However, volume was not related to 30-day readmission rate with any procedure. Conclusion Although hospital volume may be an important predictor of operative mortality, it is not associated with resource use as reflected by length of stay or readmission rates.

Use of hospitals, physician visits, and hospice care during last six months of life among cohorts loyal to highly respected hospitals in the United States

Abstract Objective To evaluate the use of healthcare resources during the last six months of life among patients of US hospitals with strong reputations for high quality care in managing chronic illness. Design Retrospective cohort study based on claims data from the US Medicare programme. Participants Cohorts receiving most of their hospital care from 77 hospitals that appeared on the 2001 US News and World Report “best hospitals” list for heart and pulmonary disease, cancer, and geriatric services. Main outcome measures Use of healthcare resources in the last six months of life: number of days spent in hospital and in intensive care units; number of physician visits; percentage of patients seeing 10 or more physicians; percentage enrolled in hospice. Terminal care: percentage of deaths occurring in hospital; percentage of deaths occurring in association with a stay in an intensive care unit. Results Extensive variation in each measure existed among the 77 hospital cohorts. Days in hospital per decedent ranged from 9.4 to 27.1 (interquartile range 11.6-16.1); days in intensive care units ranged from 1.6 to 9.5 (2.6-4.5); number of physician visits ranged from 17.6 to 76.2 (25.5-39.5); percentage of patients seeing 10 or more physicians ranged from 16.9% to 58.5% (29.4-43.4%); and hospice enrolment ranged from 10.8% to 43.8% (22.0-32.0%). The percentage of deaths occurring in hospital ranged from 15.9% to 55.6% (35.4-43.1%), and the percentage of deaths associated with a stay in intensive care ranged from 8.4% to 36.8% (20.2-27.1%). Conclusion Striking variation exists in the utilisation of end of life care among US medical centres with strong national reputations for clinical care.

Hospital Readmission Rates for Cohorts of Medicare Beneficiaries in Boston and New Haven

BACKGROUND Geographic variations in the use of hospital services are associated with differences in the availability of hospital beds. There continues to be uncertainty about the extent to which unmeasured case-mix differences explain these findings. Previous research showed that the number of occupied beds per capita in Boston was substantially higher than the number of occupied beds per capita in New Haven, Connecticut, and that overall rates of hospital utilization were higher for Boston residents than for New Haven residents. METHODS We used Medicare claims data to study cohorts of Medicare beneficiaries 65 years of age or older and residing in Boston or New Haven who were initially hospitalized for one of five indications (acute myocardial infarction, stroke, gastrointestinal bleeding, hip fracture, or potentially curative surgery for breast, colon, or lung cancer). Residents of Boston or New Haven who were discharged between October 1, 1987, and September 30, 1989, were enrolled in the cohort corresponding to the earliest such admission and followed for up to 35 months. RESULTS The relative rate of readmission in Boston as compared with New Haven was 1.64 (95 percent confidence interval, 1.53 to 1.76) for all cohorts combined, with a similarly elevated rate for each of the five clinical cohorts and each age, sex, and race subgroup examined. Hospital-specific readmission rates varied substantially among the hospitals in Boston and were higher than those in New Haven. No relation was found between mortality (during the first 30 days after discharge or over the entire study period) and either community or hospital-specific readmission rates. CONCLUSIONS Regardless of the initial cause of the admission, Medicare beneficiaries who were initially hospitalized in Boston had consistently higher rates of readmission than did Medicare beneficiaries hospitalized in New Haven. Differences in the severity of illness are unlikely to explain these findings. One possible explanation is a threshold effect of hospital-bed availability on decisions to admit patients.

Race and Surgical Mortality in the United States

Objective:This study describes racial differences in postoperative mortality following 8 cardiovascular and cancer procedures and assesses possible explanations for these differences. Summary Background Data:Although racial disparities in the use of surgical procedures are well established, relationships between race and operative mortality have not been assessed systematically. Methods:We used national Medicare data to identify all patients undergoing one of 8 cardiovascular and cancer procedures between 1994 and 1999. We used multiple logistic regression to assess differences in operative mortality (death within 30 days or before discharge) between black patients and white patients, controlling for patient characteristics. Adding hospital indicators to these models, we then assessed the extent to which racial differences in operative mortality could be accounted for by the hospital in which patients were cared for. Results:Black patients had higher crude mortality rates than white patients for 7 of the 8 operations, including coronary artery bypass, aortic valve replacement, abdominal aortic aneurysm repair, carotid endarterectomy, radical cystectomy, pancreatic resection, and esophagectomy. Among these 7 procedures, odds ratios of mortality (black versus white) ranged from 1.23 (95% confidence interval, 1.18–1.29) for CABG to 1.61 (95% confidence interval, 1.28–2.03) for esophagectomy. Adjusting for patient characteristics had modest or no effect on odds ratios of mortality by race. However, there remained few clinically or statistically significant differences in mortality by race after we accounted for hospital. Hospitals that treated a large proportion of black patients had higher mortality rates for all 8 procedures, for white as well as black patients. Conclusions:Black patients have higher operative mortality risks across a wide range of surgical procedures, in large part because of higher mortality rates at the hospitals they attend.

Association Between Colonoscopy and Colorectal Cancer Mortality in a US Cohort According to Site of Cancer and Colonoscopist Specialty

PURPOSE We designed this study to evaluate the association of colonoscopy with colorectal cancer (CRC) death in the United States by site of CRC and endoscopist specialty. METHODS We designed a case-control study using Surveillance, Epidemiology, and End Results (SEER)-Medicare data. We identified patients (cases) diagnosed with CRC age 70 to 89 years from January 1998 through December 2002 who died as a result of CRC by 2007. We selected three matched controls without cancer for each case. Controls were assigned a referent date (date of diagnosis of the case). Colonoscopy performed from January 1991 through 6 months before the diagnosis/referent date was our primary exposure. We compared exposure to colonoscopy in cases and controls by using conditional logistic regression controlling for covariates, stratified by site of CRC. We determined endoscopist specialty by linkage to the American Medical Association (AMA) Masterfile. We assessed whether the association between colonoscopy and CRC death varied with endoscopist specialty. RESULTS We identified 9,458 cases (3,963 proximal [41.9%], 4,685 distal [49.5%], and 810 unknown site [8.6%]) and 27,641 controls. In all, 11.3% of cases and 23.7% of controls underwent colonoscopy more than 6 months before diagnosis. Compared with controls, cases were less likely to have undergone colonoscopy (odds ratio [OR], 0.40; 95% CI, 0.37 to 0.43); the association was stronger for distal (OR, 0.24; 95% CI, 0.21 to 0.27) than proximal (OR, 0.58; 95% CI, 0.53 to 0.64) CRC. The strength of the association varied with endoscopist specialty. CONCLUSION Colonoscopy is associated with a reduced risk of death from CRC, with the association considerably and consistently stronger for distal versus proximal CRC. The overall association was strongest if colonoscopy was performed by a gastroenterologist.

Surgeon Volume and Operative Mortality in the United States

Objectives:Although recent studies suggest that physician age is inversely related to clinical performance in primary care, relationships between surgeon age and patient outcomes have not been examined systematically. Methods:Using national Medicare files, we examined operative mortality in approximately 461,000 patients undergoing 1 of 8 procedures between 1998 and 1999. We used multiple logistic regression to assess relationships between surgeon age (≤40 years, 41–50 years, 51–60 years, and >60 years) and operative mortality (in-hospital or within 30 days), adjusting for patient characteristics, surgeon procedure volume, and hospital attributes. Results:Although older surgeons had slightly lower procedure volumes than younger surgeons for some procedures, there were few clinically important differences in patient characteristics by surgeon age. Compared with surgeons aged 41 to 50 years, surgeons over 60 years had higher mortality rates with pancreatectomy (adjusted odds ratio [OR], 1.67; 95% confidence interval [CI], 1.12–2.49), coronary artery bypass grafting (OR, 1.17; 95% CI, 1.05–1.29), and carotid endarterectomy (OR, 1.21; 95% CI, 1.04–1.40). The effect of surgeon age was largely restricted to those surgeons with low procedure volumes and was unrelated to mortality for esophagectomy, cystectomy, lung resection, aortic valve replacement, or aortic aneurysm repair. Less experienced surgeons (≤40 years of age) had comparable mortality rates to surgeons aged 41 to 50 years for all procedures. Conclusions:For some complex procedures, surgeons older than 60 years, particularly those with low procedure volumes, have higher operative mortality rates than their younger counterparts. For most procedures, however, surgeon age is not an important predictor of operative risk.

Surgeon Specialty and Operative Mortality With Lung Resection

Objective:We sought to examine the effect of subspecialty training on operative mortality following lung resection. Summary Background Data:While several different surgical subspecialists perform lung resection for cancer, many believe that this procedure is best performed by board-certified thoracic surgeons. Methods:Using the national Medicare database 1998 to 1999, we identified patients undergoing lung resection (lobectomy or pneumonectomy) for lung cancer. Operating surgeons were identified by unique physician identifier codes contained in the discharge abstract. We used the American Board of Thoracic Surgery database, as well as physician practice patterns, to designate surgeons as general surgeons, cardiothoracic surgeons, or noncardiac thoracic surgeons. Using logistic regression models, we compared operative mortality across surgeon subspecialties, adjusting for patient, surgeon, and hospital characteristics. Results:Overall, 25,545 Medicare patients underwent lung resection, 36% by general surgeons, 39% by cardiothoracic surgeons, and 25% by noncardiac thoracic surgeons. Patient characteristics did not differ substantially by surgeon specialty. Adjusted operative mortality rates were lowest for cardiothoracic and noncardiac thoracic surgeons (7.6% general surgeons, 5.6% cardiothoracic surgeons, 5.8% noncardiac thoracic surgeons, P = 0.001). In analyses restricted to high-volume surgeons (>20 lung resections/y), mortality rates were lowest for noncardiac thoracic surgeons (5.1% noncardiac thoracic, 5.2% cardiothoracic, and 6.1% general surgeons) (P < 0.01 for difference between general surgeons and thoracic surgeons). In analyses restricted to high-volume hospitals (>45 lung resections/y), mortality rates were again lowest for noncardiac thoracic surgeons (5.0% noncardiac thoracic, 5.3% cardiothoracic, and 6.1% general surgeons) (P < 0.01 for differences between all 3 groups). Conclusions:Operative mortality with lung resection varies by surgeon specialty. Some, but not all, of this variation in operative mortality is attributable to hospital and surgeon volume.