“Little risk-adjusted variation exists in hospital readmission rates after colorectal surgery,” according to an analysis of data from 44,822 patients who underwent colorectal resection for cancer at 1,401 U.S. hospitals between 1997 and 2002. “The use of readmission rates as a high-stakes quality measure for payment adjustment or public reporting across surgical specialties should proceed cautiously and must include appropriate risk adjustment,” concluded Donald L. Lucas, MD, MPH, and colleagues from Walter Reed National Military Medical Center, Bethesda, and Johns Hopkins University School of Medicine, Baltimore.
“Readmission has become a major hospital quality metric, but it is unclear whether there is much difference in readmission among hospitals after appropriate risk adjustment,” the authors wrote in JAMA Surgery.
To assess the variability in risk-adjusted readmission rates following colorectal surgery, the researchers performed a hierarchical multivariable logistic regression analysis of observational data obtained from the Surveillance, Epidemiology, and End Results Medicare–linked database. The authors pointed out that compared with multivariable analyses, hierarchical models “better account for the statistical uncertainty related to low case volumes seen at the hospital level.” In addition, “hierarchical modeling for hospital profiling has been endorsed by the Committee of Presidents of Statistical Societies,” as well as the Centers for Medicare & Medicaid Services and the American College of Surgeons National Surgical Quality Improvement Program.
The median age of the study patients was 78 years; 87.1% were non-Hispanic white; and 55.2% were female. Most patients (37,228 [83.1%]) underwent a colectomy, most commonly a right colectomy (20,881 patients [46.6%]), and 7,534 patients (16.8%) underwent a proctectomy.
On adjusted analysis, risk of readmission increased progressively with age and among patients of black race. Operations most associated with readmission were total abdominal colectomy and abdominoperineal resection. Patients undergoing sigmoid colectomy had a decreased risk of readmission. Comorbidities associated with increased readmission included congestive heart failure, chronic obstructive pulmonary disease, and cerebrovascular disease.
The overall 30-day readmission rate was 12.3%. “Looking at hospitals that performed at least five operations annually, we found marked variation in raw readmission rates, with a range of 0% to 41.2% (interquartile range [IQR], 9.5%–14.8%). However, after adjusting for patient characteristics, comorbidities, and operation types in a hierarchical model, no significant variability was found in readmission rates among hospitals, with a range of 11.3% to 13.2% (IQR, 12.1%–12.4%),” the investigators stated. ■
Lucas DJ, et al: JAMA Surg. October 22, 2014 (early release online).