Clinical outcomes and patient-reported outcome measures among patients undergoing posterior lumbar fusion procedures with varying insurance payor status: a propensity score-matching study.

OBJECTIVE

Posterior lumbar fusion (PLF) is a routinely used procedure for treatment of spinal pathology. Several studies have highlighted disparities in reoperation and postoperative complications and demonstrated associations between differing insurance providers, complication rates, and hospital resource utilization in spine surgery. Previous studies have examined broad spinal procedures but have not extended to uninsured patients, or adjusted for sociodemographic factors or comorbidity history. Understanding relationships between payor status and outcomes following fusion procedures is vital to promoting healthcare equity. The objective of this study was to assess whether patients' insurance impacts postoperative outcomes and patient satisfaction following PLF procedures.

METHODS

The Stanford University Medical Center inpatient registry was used to retrospectively analyze patients who underwent PLF procedures between 2016 and 2022. Propensity score matching was used to compare privately insured with Medicaid patients, as well as comparing uninsured patients with Medicaid patients based on age, sex, and comorbidities. Outcomes data, including 90-day postoperative complications, reoperation, and patient-reported outcome measures scores (Oswestry Disability Index and Patient Health Questionnaire) were collected.

RESULTS

A total of 1904 patients fulfilled the inclusion criteria. In unmatched comparisons, statistically significant differences existed within specific types of complications including altered mental status, delirium, neurological complications, and pulmonary complications. A total of 292 privately insured patients were matched to 292 Medicaid patients. Within matched patient groups, the Medicaid group had higher rates of altered mental status (6.2% vs 2.7%, p = 0.042); delirium (9.9% vs 5.1%, p = 0.035); renal dysfunction (6.9% vs 4.1%, p = 0.020); and pulmonary complications (8.9% vs 3.8%, p = 0.049) compared to privately insured patients. Privately insured patients had lower postoperative Oswestry Disability Index scores (30.2 vs 34.4, p = 0.018) compared to Medicaid patients. Following propensity score matching of 88 Medicaid patients to 88 uninsured patients, large but not statistically significant differences existed for neurological complications (12.5% vs 5.7%, p = 0.165) and 5-year revision rates (3.4% vs 1.1%, p = 0.353).

CONCLUSIONS

The findings indicate that the treatment outcomes, care quality, and patient satisfaction following PLF procedures differ between Medicaid and privately insured patients. Further investigation is warranted to explore relationships between insurance payor status and clinical outcomes in multicenter populations.