Mortality and associated factors of juvenile idiopathic arthritis in hospitalized Thai children: a nationwide data analysis 2015-2023

OBJECTIVE: To characterize in-hospital mortality, respiratory failure requiring endotracheal intubation, and associated comorbidities among hospitalized children with juvenile idiopathic arthritis (JIA) using nationwide data from Thailand. METHODS: We conducted a retrospective study using administrative inpatient data from Thailand's National database from January 2015 to December 2023. All hospital admissions for patients younger than 18 years with JIA were included. Primary outcomes were in-hospital mortality and respiratory failure, defined by endotracheal intubation. Demographics, JIA subtypes, hospital level, healthcare utilization, and comorbidities were analyzed. Multivariable logistic regression identified comorbidities independently associated with intubation, reported as adjusted odds ratios (aORs) with 95% confidence intervals. RESULTS: Among 3,754 JIA admissions, 52.7% of patients were female, with a median age of 10 years (interquartile range 6-13). Endotracheal intubation occurred in 39 admissions (1.0%), and 17 patients died, yielding an in-hospital mortality rate of 0.5%; mortality among intubated patients was 33.3%. Length of stay and costs were substantially higher among intubated patients and non-survivors. Pneumonia was common in both groups. Myocarditis showed the strongest association with intubation (aOR 294.74), followed by pulmonary hemorrhage, acute kidney injury, and septic shock. Macrophage activation syndrome was identified in 43 admissions (1.2%) and was more frequent among non-survivors (23.5% vs 1.0%; P < 0.001). CONCLUSIONS: Although overall mortality and intubation rates were low, respiratory failure identified a small, high-risk subgroup with substantial mortality and healthcare burden. Severe outcomes were driven by acute multi-organ complications, underscoring early recognition and aggressive management of high-risk comorbidities.