Hospital cost associated with anemia in elective colorectal surgery: a historical cohort study

Anemia is highly prevalent in the colorectal surgery population, affecting 30-70% of patients. Anemia is associated with significant morbidity and mortality; however, there is a lack of evidence on how much anemia impacts healthcare costs. This study aims to determine the hospital cost of index surgical admission, postoperative length of stay, and transfusion rate associated with preoperative anemia in elective major colorectal surgery.

This historical cohort study included 851 adult inpatients having elective colorectal surgery at a tertiary care academic health sciences network between April 2010 and February 2016. Anemia was defined as hematocrit ≤ 39%. The primary outcome was total hospital costs standardized to 2016 CAD. Secondary outcomes were postoperative length of stay and transfusion. Multivariable regression analyses and propensity score methods were used to measure adjusted associations between anemia and outcomes.

Before surgery, 381/851 (45%) patients were anemic. The mean (standard deviation [SD]) cost of index admission for an elective colorectal surgery was 20,040 (23,219) CAD. Anemia was associated with an adjusted 14% relative increase in costs (95% confidence interval [CI], 6 to 23; P < 0.001). The total hospitalization cost attributable to anemia was 3,027 CAD (95% CI, 2,670 to 3,388). Hospital costs and length of stay were highly associated; anemia was associated with an 18% increase in length of stay (95% CI, 7 to 30; P < 0.001) and increased transfusion rates (risk ratio, 4.7; 95% CI, 2.71 to 8.33; P < 0.001).

Over 2,600 CAD per index surgical admission is attributable to preoperative anemia. Preoperative interventions with per patient cost of less than 2,600 CAD could be cost effective at the hospital level.

www.clinicaltrials.gov (NCT03476707); registered 26 March, 2018.