Predictive Model of Dynamic Subphenotypes for 30-Day Mortality in Emergency Department Patients with Suspected Infection Using the Vital Signs of the First 24 Hours: An Analytical Cohort Study in a Tertiary Care Clinic

<b>Background/Objectives</b>: To determine and validate the cluster trajectory model by dynamic subphenotypes of vital signs in infecti ons and prediction of 30-day mortality. <b>Methods:</b> We conducted a prospective study in the emergency department of Clínica Colombia with patients with suspected infection. Clinical data, vital signs, and 30-day mortality were collected. Vital signs were measured within the first 24 h of admission, and patients were classified according to a vital signs trajectory model into four groups: A, B, C, and D. <b>Results</b>: The final cohort consisted of 625 patients, and the subphenotypes, according to the vital signs, were as follows: A-2.66% (all vital signs altered), B-9.2% (at least one alteration, predominantly hypertension), C-19% (minimal or no alteration, control), D-69.2% (only arterial hypotension). The primary outcome was mortality. Overall mortality was 8.6%, being higher in group A followed by D, B and C (<i>p</i> = 0.009). The risk increased progressively in groups B (OR = 2.87, CI 95%: 0.62-13.25), D (OR = 4.77, CI 95%: 1.46-15.58), and A (OR = 8.33, CI 95%: 1.54-45.05). Group A presented more frequently with pneumonia (<i>p</i> = 0.002), CNS infections (<i>p</i> = 0.021), mechanical ventilation (<i>p</i> < 0.001), and vasopressor support (<i>p</i> < 0.001). Significant differences among groups were found in leukocytosis (B vs. C <i>p</i> = 0.026), neutrophilia (B vs. C <i>p</i> = 0.001 and B vs. D <i>p</i> = 0.042), lymphocytosis (B vs. D <i>p</i> = 0.002), neutrophil/lymphocyte ratio (A vs. C <i>p</i> = 0. 010), lactate (C vs. D <i>p</i> = 0.044), anemia (B vs. D <i>p</i> = 0.013 and C vs. D <i>p</i> = 0.001), and CRP (A vs. C <i>p</i> = 0.004, B vs. C <i>p</i> < 0.001 and C vs. D <i>p</i> < 0.001). <b>Conclusions</b>: Patients with suspected infection and more altered vital signs have higher mortality (group A) and benefit from earlier interventions by sepsis teams in the emergency department.