IntroductionReadmissions after a traumatic brain injury (TBI) can have severe impacts on long-term health outcomes as well as rehabilitation. The aim of this descriptive study was to analyze the Nationwide Readmissions Database to determine possible risk factors associated with readmission for patients who previously sustained a TBI. MethodsThis retrospective study used data from the Nationwide Readmissions Database to explore gender, age, injury severity score, comorbidities, index admission hospital size, discharge disposition of the patient, and cause for readmission for adults admitted with a TBI. Multivariable logistic regression was used to assess likelihood of readmission. ResultsThere was a readmission rate of 28.7% (n = 31,757) among the study population. The primary cause of readmission was either subsequent injury or sequelae of the original injury (n = 8825; 29%) followed by circulatory (n = 5894; 19%) and nervous system issues (n = 2904; 9%). There was a significantly higher risk of being readmitted in males (Female odds ratio: 0.87; confidence interval [0.851-0.922), older patients (65-79: 32.3%; > 80: 37.1%), patients with three or more comorbidities (≥ 3: 32.9%), or in patients discharged to a skilled nursing facility/intermediate care facility/rehab (SNF/ICF/Rehab odds ratio: 1.55; confidence interval [0.234-0.262]). ConclusionsThis study demonstrates a large proportion of patients are readmitted after sustaining a TBI. A significant number of patients are readmitted for subsequent injuries, circulatory issues, nervous system problems, and infections. Although readmissions cannot be completely avoided, defining at-risk populations is the first step of understanding how to reduce readmissions.