Risk factors for readmission after lower extremity procedures for peripheral artery disease

Abstract

As pressure to contain health care costs increases, there has been greater scrutiny of readmissions in the vascular surgery population. The objective of this study was to evaluate postoperative readmissions after open and endovascular lower extremity (LE) procedures for peripheral artery disease (PAD). A retrospective cohort study was performed of elective adult inpatients with PAD and LE procedures which were selected from the Health Facts database (Cerner Corporation, Kansas City, Mo) between October 2008 and December 2010 using International Classification of Disease, 9th Clinical Modification diagnosis codes (claudication, rest pain, and ulceration/gangrene) and procedure codes for LE revascularization (endovascular and open). Multivariable logistic regression and χ(2) were used to compare patients who received endovascular and open procedures. The Charlson Comorbidity Index, comorbid diagnoses, and laboratory results were used to adjust for confounding. The main outcome measure evaluated was readmission ≤ 30 days of discharge. Of 463,362 index admissions, 16,574 patients were identified with a diagnosis of PAD. Combining PAD with elective LE procedures during the index admission, 777 underwent open and 681 underwent endovascular procedures. Unadjusted readmission rates for open and endovascular procedures for claudication, rest pain, and ulceration/gangrene were 10.2% vs 11.3% (P = .69), 14.0% vs 18.2% (P = .43), and 21.1% vs 19.5% (P = .69), respectively. Readmission increased by the severity of the diagnosis for open and endovascular procedures (P = .0006). Men comprised 58% of the cohort; readmission rates were not statistically different by sex (P = .19). Race was not associated with procedure performed (P = .16), but nonwhite race was associated with more severe PAD (P < .0001). After adjusting for race, sex, comorbidities, length of stay, and laboratory values outside of normal reference ranges, the association between an endovascular procedure and readmission was not statistically significant (odds ratio, 1.28; 95% confidence interval, 0.94-1.75). Less invasive endovascular procedures were not associated with decreased readmission rates compared with open surgery. The overall readmission rate for claudicant patients was 10.7%, which was unexpectedly high. Predictors of readmission included male sex, longer hospital stays, hospital infection, elevated aspartate aminotransferase, and high numbers of medications ordered and dispensed. Further examination exploring reasons for readmission are required to decrease readmission rates in the vascular surgery population.