The association of anaemia and its severity with composite morbidity after total hip arthroplasty

Abstract

Background: Total hip arthroplasty (THA) is a common orthopaedic procedure and is expected to increase with an increasing elderly population. Many of these patients suffer from chronic diseases which might be associated with anaemia. Anaemia, by itself, increases the risk of morbidity. We aimed to delineate relationship between preoperative anaemia and postoperative composite morbidities in patients undergoing primary THA. Methods: A cohort study analysed the data from the American College of Surgeons National Surgical Quality Improvement Program 2008–2014 database. Adult patients who underwent unilateral primary THA were included and divided into 3 groups: no anaemia, mild anaemia, and moderate-to-severe anaemia. Thirty-day mortality and morbidity were recorded as adverse events. The associations between anaemia, baseline characteristics, and adverse events were analysed after adjusting for confounders. Results: Moderate-to-severe anaemia patients were at increased risk for composite morbidity (adjusted odds ratio, 1.43 [1.17–1.74]) when compared to non-anaemics. The stratification revealed a significant effect of younger age, male gender, white race, obesity, general anaesthesia, and mean operative time >120 minutes in patients with moderate-to-severe anaemia. These patients were also at a higher risk of developing several specific morbidities. Conclusion: Moderate-to-severe anaemia increases the risk for composite morbidities, but not mortality in patients undergoing primary THA. Further studies are needed to assess whether preoperative management of moderate-to-severe anaemia would improve outcomes in patients undergoing THA.