The LACE Index is a standardized clinical prediction tool designed to calculate a patient’s risk of an unplanned hospital readmission or death within 30 days following discharge. It helps healthcare providers systematically identify patients most vulnerable during the transition from hospital to home. The score serves as a method for triaging patients, ensuring those with the highest calculated risk receive enhanced support and transitional care services. It uses routinely collected administrative and clinical data, making it a practical tool for hospital operations.
The Four Components of the LACE Score
The LACE acronym represents the four factors used in the risk calculation: Length of stay (L), Acuity of admission (A), Comorbidities (C), and Emergency department use (E) in the six months prior to admission. Points are assigned for each factor, and the total score ranges from zero to a maximum of 19, with a higher number correlating with a greater risk of an adverse outcome.
The L for Length of stay assigns points based on the duration of the hospital admission. A one-day stay typically earns one point, while a stay of 14 days or longer can contribute up to seven points to the total LACE score. Prolonged hospitalizations often reflect greater illness severity or complexity, increasing the likelihood of post-discharge complications.
The A for Acuity of admission focuses on how the patient entered the hospital for the index stay. Patients admitted directly through the emergency department (ED) are assigned three points, while those who had a planned or elective admission receive zero points. An ED admission suggests a sudden, urgent medical event, which is a predictor of instability after discharge.
The C for Comorbidities is calculated using a modified version of the Charlson Comorbidity Index, which quantifies the severity and number of pre-existing chronic medical conditions. Conditions like congestive heart failure, renal disease, and various cancers are assigned specific point values. The total score for this component is capped, typically at five points, ensuring that the presence of multiple severe chronic illnesses increases the overall LACE score.
The E for Emergency department use accounts for the patient’s healthcare utilization history in the six months before the current hospital stay. One point is added for each ED visit within the preceding six months, excluding the visit that led to the current admission. Frequent recent ED visits often signal difficulty managing chronic conditions or inadequate outpatient support, contributing a maximum of four points to the total score.
Interpreting High, Moderate, and Low Risk Scores
The total LACE score stratifies patients into three distinct risk categories for readmission or death within 30 days. This stratification guides the intensity of post-discharge planning and intervention. Standard cutoffs define scores of 0 to 4 as low risk, 5 to 9 as moderate risk, and a score of 10 or greater as high risk.
A score in the low-risk range (0-4) suggests a low probability of an adverse event following discharge. This group typically has a very small proportion of patients who died within 30 days (approximately 0.1%). Patients in this group are expected to manage their recovery with standard discharge instructions and follow-up care.
The moderate-risk group (scores between 5 and 9) indicates an intermediate probability of rehospitalization or death. The proportion of patients who died within 30 days for this group rose to 1.4%, showing an increase in vulnerability compared to the low-risk category. Patients in this range typically benefit from targeted transitional care services, such as a follow-up phone call from a nurse.
A score of 10 or greater is considered a high LACE score and signals a substantially elevated risk for an unplanned readmission or death. Patients with this score have a significantly greater likelihood of needing further acute care within 30 days. Patients in the high-risk group have an odds ratio for readmission that is more than two-and-a-half times higher compared to those in the low-risk group.
The impact of a high score is also evident in mortality rates, rising sharply to 6.8% for those with a score of 10 or above. This numerical threshold of 10 signals to the healthcare team that the patient’s transition home requires intensive support.
Post-Discharge Care Based on LACE Results
The primary value of the LACE score is directing resources to the patients who need them most to prevent adverse outcomes. Patients in the moderate and high-risk categories receive enhanced transitional care interventions. This approach ensures that limited resources are focused on managing the most complex and vulnerable patient discharges.
For individuals with high LACE scores, an aggressive action plan is immediately implemented to manage the transition from the hospital. This often includes a structured follow-up call from a nurse or care coordinator, ideally within 72 hours of discharge, to confirm appointments and address immediate concerns. The goal of this early outreach is to resolve issues like medication confusion or new symptoms before they escalate.
Enhanced post-discharge care also involves arranging for an early follow-up appointment with a primary care provider or specialist, sometimes mandated within 14 days for the highest-risk patients. This includes comprehensive medication reconciliation, where a clinician reviews the patient’s complete list of medications to ensure accuracy and adherence to the discharge plan.
High LACE scores often trigger referrals for home health services, where a nurse or therapist visits the patient’s home to provide education and monitor their status. This application ensures that the most vulnerable patients receive heightened monitoring, mitigating the risk factors identified by the LACE calculation.