Impact of Comorbidities on Hospitalization Costs Following Hip Fracture

Abstract

Comorbidities significantly affect the cost of hospitalization and length of stay following hip fracture in older Americans, even while controlling for other variables.

The Elixhauser Comorbidity Method Outperforms the Charlson Index in Predicting Inpatient Death After Orthopaedic Surgery

“…Overall, the AUC values for inpatient mortality for the Charlson and Elixhauser comorbidity-based measures in our study were comparable to or slightly higher than those described in other patient populations [6,18,27,52]. Consistent with a study by Nikkel et al [39] in patients with hip fractures, the Elixhauser weight loss or malnutrition comorbidity was the major factor influencing mortality. We found some comorbidities (eg, hypothyroidism, obesity, uncomplicated diabetes, hypertension) to be associated with decreased odds of inpatient mortality.…”

“…First, the NHDS dataset is based on billing data from ICD-9-CM codes, and such a coding system may not fully capture the patient population of interest [1]. In particular, it has been suggested that administrative databases tend to underreport chronic medical conditions that are considered less acute in the perioperative orthopaedic surgery setting [16,31,33,34,39]. Second, the possibility of errors in coding of the diagnoses and procedures cannot be avoided [7]; however, misclassification mistakes distribute evenly in large-scale studies [53].…”

“…The Elixhauser measure has not been introduced in orthopaedic surgery research until recently [17,26,39,57,59,60], perhaps because of scarce reported comparisons with the Charlson model [17] and concerns regarding the inclusion of too many explanatory variables (31 variables), therefore requiring a relatively large sample size [27]. The main attractiveness of the use of large administrative databases for medical research lies in the possibility of studying rare occurrence events, such as inpatient mortality, that otherwise would be difficult to investigate in small population studies [14].…”

“…Patients undergoing orthopaedic surgery often have multiple coexisting medical conditions (comorbidities) [13,21,24,28,39,45,58]. Preoperative risk assessment can help with decision-making and management strategies [11,37,50].…”

“…Large administrative inpatient databases have been used to assess the effect of baseline comorbidity status on surgical care outcomes targeted in pay-for-performance initiatives such as mortality, morbidity, and discharge disposition [14,22,[32][33][34][37][38][39]. The Charlson Comorbidity Index [5] encompasses 19 medical conditions and is the most widely used comorbidity risk adjustment model in orthopaedic surgery.…”