The LACE index and risk factors of 14-day versus 30-day readmissions in children

Abstract

Risk factors for readmissions in children differ from those in adults, yet little is known about whether the LACE index (Length of stay, Acute admission, Charlson comorbidity index, Emergency department visits in the previous 6 months) developed for adults retains its validity when applied to the prediction of readmissions in children or within shorter intervals of time after discharge. In this retrospective cohort analysis of 4256 patients aged ≤18 years hospitalized at one academic medical center in Taiwan in 2019, we first evaluated the performance of a LACE index model and the three other multivariate logistic regression models in their predictions of hospital readmissions in children using the same time interval of 30 days. We then used multinomial logistic regression to analyze the characteristics and risk factors for readmissions that occur in the first 14 days with those that occur between 15 and 30 days after discharge. The optimal cut-off of the LACE index score for children in the current study was 7, which is less than the optimal score of 10 in the original derivation for adults. The predictive model with the least discriminatory power was based on the LACE score alone, whereas our model that included only two variables (length of stay and the number of admissions in the past 1 year) was found to outperform the LACE index. Multinomial logistic regression results revealed that children who had supplemental private health insurance had lower readmission rates than those insured by the National Health Insurance program only, suggesting a disparity by insurance status. Some risk factors of readmission within 14 days such as acute admissions and supplemental private health insurance were not found to be relevant for longer-term predictions, while age, which was a valid predictor of readmission within 15-30 days, did not affect the prediction of shorter-term readmissions. Prior health care utilization and a higher illness burden were found to be greater contributors to readmissions beyond 14 days. Our simpler model outperformed the more complex LACE tool in identifying children at risk of readmission. Shorter-term readmissions can be attributed to different causes than 30-day readmissions, suggesting a need for different screening tools, interventions, and care support. There remains some socioeconomic disparity associated with readmission rates in the current health care system.

Keywords: 14-day versus 30-day readmission; LACE index; disparity; private health insurance; risk management.