Factors associated with lumbar fusion surgery: a case-control study.

Abstract

The objective of this study is to identify the demographic and payer factors that are associated with lumbar fusion surgery. A case-control study was conducted utilizing a population of 38,092 patients from the 2010 Florida Agency for Health Care Administration (AHCA), USA hospital discharge data. The case population included 16,236 records with any of five ICD-9-CM principal procedure codes for initial lumbar fusion. The control group was comprised of 21,856 patients who were admitted for the same principal diagnoses as the cases, but who did not have initial fusion surgery. Logistic regression was used to analyze the association of age, gender, race and principal payer type with initial lumbar fusions. The interaction between age and payer was also examined, as payer type may moderate the association between age and lumbar fusion surgery. Gender, race, principal payer and age were all found to be significantly associated with lumbar fusion surgery. The interaction of payer and age was also found to be significant. Being female was significantly associated with having a fusion (OR=1.11, 95% CI 1.07-1.16). The association between age and receiving surgery was greatest for the less than 20 age group (OR=10.43, 95% CI 8.74-12.45). Employees and dependents of Federal government agencies (Tricare, etc.) and patients with commercial insurance were significantly associated with surgery (OR=1.48, 95% CI 1.29-1.70 and OR=1.12, 95% CI 1.04-1.20, respectively). Patients insured through Medicaid (a social health care program for those with low incomes and limited resources), and the uninsured were negatively associated with surgery (OR=0.53, 95% CI 0.47-0.60 and OR=0.52, 95% CI 0.46-0.58, respectively). Lumbar fusion surgery is not recommended in clinical practice guidelines for the top four principal diagnoses in this study. Yet, patients covered by certain types of insurance were found to be significantly associated with fusion surgery.