Validation of the LACE Index (Length of Stay, Acuity of Admission, Comorbidities, Emergency Department Use) in the Adult Neurosurgical Patient Population

BACKGROUND: The LACE index (Length of stay, Acuity of admission, Comorbidities, Emergency department use) quantifies the risk of mortality or unplanned readmission within 30 d after hospital discharge. The index was validated originally in a large, general population and, subsequently, in several specialties, not including neurosurgery. OBJECTIVE: To determine if the LACE index accurately predicts mortality and unplanned readmission of neurosurgery patients within 30 d of discharge. METHODS: We performed a retrospective, cohort study of consecutive neurosurgical procedures between January 1 and September 29, 2017 at our institution. The LACE index and other clinical data were abstracted. Data analysis included univariate and multivariate logistic regressions. RESULTS: Of the 1,054 procedures on 974 patients, 52.7% were performed on females. Mean age was 54.2 ± 15.4 yr. At time of discharge, the LACE index was low (1-4) in 58.3% of patients, moderate (5-9) in 32.4%, and high (10-19) in 9.3%. Rates of readmission and mortality within 30 d were 7.0, 11.4, and 14.3% in the low-, moderate-, and high-risk groups, respectively. Moderate-risk (odds ratio [OR] 1.62, 95% CI 1.02-2.56, P = .04) and high-risk LACE indexes (OR 2.20, 95% CI 1.15-4.19, P = .02) were associated with greater odds of readmission or mortality, adjusting for all variables. Additionally, longer operations (OR 1.11, 95% CI 1.02-1.21, P = .02) had greater odds of readmission. Specificity of the high-risk score to predict 30-d readmission or mortality was 91.2%. CONCLUSION: A moderate- or high-risk LACE index can be applied to neurosurgical populations to predict 30-d readmission and mortality. Longer operations are potential predictors of readmission or mortality.