OBJECTIVES

Spinal infection is associated with multiple medical conditions including diabetes mellitus (DM), illicit drug use, endocarditis, chronic kidney disease, human immunodeficiency virus, and cirrhosis. To better characterize the complexity of and payer costs associated with spine infection-related hospitalizations and comorbid conditions, we assessed a United States (U.S.) inpatient sample during a nine-year period.

METHODS

Patients hospitalized with spinal infection and associated medical conditions between 2006-2014 were identified with International Classification of Diseases-9 (ICD-9) diagnoses in the U.S. Healthcare Cost and Utilization Project (HCUPNet) publicly-available data tools. We assessed patient volumes and changes over time in hospital discharges, male/female ratio, age distribution, payer mix, and HCUP calculated aggregate payer costs.

RESULTS

The number of U.S. patients discharged with a diagnosis of spine infection increased 5% (24,179-25,320) from 2006-2014. Associated Medicare and Medicaid beneficiary volumes increased 12% and 71%, respectively, while commercially-insured patients decreased 27%. Aggregate payer costs reflected similar patterns with Medicare costs increasing 25% ($193,254,675-$242,303,186), Medicaid costs increasing 74% ($75,486,525-$131,185,098), and private insurance costs decreasing 7% ($134,325,086-$125,069,130). Hospitalized spine-infection patients with a DM diagnosis increased 6%, while discharges with other associated comorbidities decreased. In the group of patients with spine infection and those with DM, the ratio of male/female patients, patient-age distribution, and payer mixes were similar. This was not present for the other comorbidity groups.

CONCLUSIONS

The frequency of U.S. hospitalizations for spine infection increased between 2006 and 2014. The associated volume of Medicare and Medicaid patients increased and fewer patients were commercially insured, with consistent corresponding changes in aggregate HCUPnet calculated payer costs. The increase in spine infections appeared to parallel the increase in hospitalization for diabetes mellitus, a recognized comorbidity associated with infection. Assessing correlations between spine infection and comorbidities requires further study, along with estimating the economic burden of these patients.