Correlations Between Psychiatric Disorders and Perioperative Outcomes After Lumbar Fusions: An Analysis of the National Inpatient Sample (2009-2020)

BACKGROUND: Preoperative diagnoses of psychiatric disorders have a demonstrated association with higher rates of perioperative complications. However, recent studies examining the influence of psychiatric disorders on lumbar fusion outcomes are scarce. Our objective was to determine the relationship between the most common psychiatric disorders and perioperative outcomes after lumbar fusion. METHODS: Demographic and perioperative data for patients who underwent lumbar spine fusion between 2009 and 2020 were collected from the National Inpatient Sample database. These patients were divided into 2 groups: those who were previously diagnosed with depression, bipolar disorder, or anxiety, and those who were not. Univariable and multivariable linear and logistic regression models were utilized to analyze the data. RESULTS: Of 2,877,241 patients identified in the National Inpatient Sample database as having undergone lumbar fusion, 647,951 had diagnosed psychiatric disorders, and the remaining 2,229,290 were the unaffected cohort. On multivariable analysis, patients diagnosed with psychiatric disorders had significantly increased odds of respiratory (odds ratio [OR]:1.09) and urinary (OR: 1.08) complications and experienced higher odds of mechanical injury (OR: 1.27), fusion disorders (OR: 1.62), dural tears (OR: 1.08), postprocedure anemia (OR: 1.29), longer hospital stays, and higher total costs (P < 0.001). Conversely, patients with psychiatric disorders had lower odds of neurologic injury (OR: 0.8) and wound complications (OR: 0.91) (P< 0.05). CONCLUSIONS: Patients with depression, bipolar disorder, or anxiety exhibited higher rates of certain types of complications. However, they appeared to have fewer neurological injuries and wound complications than patients without these psychiatric disorders. These findings highlight the necessity for additional studies to elucidate underlying reasons for these disparities.