Use of Latent Class Analysis and k-Means Clustering to Identify Complex Patient Profiles.

Importance: Medically complex patients are a heterogeneous group that contribute to a substantial proportion of health care costs. Coordinated efforts to improve care and reduce costs for this patient population have had limited success to date. Objective: To define distinct patient clinical profiles among the most medically complex patients through clinical interpretation of analytically derived patient clusters. Design, Setting, and Participants: This cohort study analyzed the most medically complex patients within Kaiser Permanente Northern California, a large integrated health care delivery system, based on comorbidity score, prior emergency department admissions, and predicted likelihood of hospitalization, from July 18, 2018, to July 15, 2019. From a starting point of over 5000 clinical variables, we used both clinical judgment and analytic methods to reduce to the 97 most informative covariates. Patients were then grouped using 2 methods (latent class analysis, generalized low-rank models, with k-means clustering). Results were interpreted by a panel of clinical stakeholders to define clinically meaningful patient profiles. Main Outcomes and Measures: Complex patient profiles, 1-year health care utilization, and mortality outcomes by profile. Results: The analysis included 104 869 individuals representing 3.3% of the adult population (mean [SD] age, 70.7 [14.5] years; 52.4% women; 39% non-White race/ethnicity). Latent class analysis resulted in a 7-class solution. Stakeholders defined the following complex patient profiles (prevalence): high acuity (9.4%), older patients with cardiovascular complications (15.9%), frail elderly (12.5%), pain management (12.3%), psychiatric illness (12.0%), cancer treatment (7.6%), and less engaged (27%). Patients in these groups had significantly different 1-year mortality rates (ranging from 3.0% for psychiatric illness profile to 23.4% for frail elderly profile; risk ratio, 7.9 [95% CI, 7.1-8.8], P < .001). Repeating the analysis using k-means clustering resulted in qualitatively similar groupings. Each clinical profile suggested a distinct collaborative care strategy to optimize management. Conclusions and Relevance: The findings suggest that highly medically complex patient populations may be categorized into distinct patient profiles that are amenable to varying strategies for resource allocation and coordinated care interventions.

60-day major adverse cardiac events in emergency department patients with non-low modified HEART scores.

BACKGROUND: A low (0-3) History, Electrocardiogram, Age, Risk factors and Troponin (HEART) score reliably identifies ED chest pain patients who are low risk for near-term major adverse cardiac events (MACE). To optimize sensitivity, many clinicians employ a modified HEART score by repeating troponin measurements and excluding patients with abnormal troponin values or ischemic electrocardiograms (ECGs). The residual MACE risk among patients with otherwise non-low (≥4) modified HEART scores is thus likely much lower than with non-low original HEART scores. OBJECTIVE: To explore residual 60-day MACE risks among patients with non-low modified HEART scores. METHODS: Secondary analysis of a retrospective cohort of ED patients presenting with chest pain to an integrated healthcare system between 2013 and 2015. Patients with serial troponin measurements within 6 h of ED arrival were considered for inclusion. Exclusions included an ischemic ECG, troponin values above the 99th percentile or a lack of continuous health plan coverage through the 60-day follow-up period. MACE was defined as a composite of myocardial infarction, cardiac arrest, cardiogenic shock or death. RESULTS: There were 22,976 study eligible patients encounters, 13,521 (59%) of which had non-low (≥4) modified HEART scores. The observed 60-day MACE risk among non-low HEART score patients was 2.0% (95% CI 1.8-2.3). When including all coronary revascularizations (MACE-R), the risk was 4.4% (95% CI 4.1-4.4). CONCLUSION: Risk of near-term MACE among patients with non-low modified HEART scores (excluding those with abnormal troponin or ischemic ECGs) appears to be much lower than in the original HEART score validation studies.