Clinical Characteristics and Hospital Course of Children with Down Syndrome Hospitalized with Pneumonia: A Three-Group Comparative Study

Background Children with Down syndrome (DS) are recognized as a high-risk population for respiratory infections; however, direct comparisons of pneumonia outcomes between children with DS, previously healthy children, and children with other chronic underlying conditions remain limited. Methods We conducted a retrospective, cross-sectional study of children hospitalized with pneumonia at King Saud University Medical City between May 2015 and March 2020. Patients were categorized into three groups: previously healthy children, children with Down syndrome, and children with other chronic underlying conditions. Demographic characteristics, markers of disease severity, and hospital course were compared. Continuous variables were analyzed using non-parametric tests and reported as median (IQR). Categorical variables were compared using chi-square or Fisher’s exact tests. Pairwise comparisons focused on Down syndrome. Results A total of 456 children were included: 233 (51.1%) previously healthy, 26 (5.7%) with Down syndrome, and 197 (43.2%) with other chronic conditions. Oxygen supplementation was required more frequently in children with Down syndrome compared with previously healthy children (88.5% vs 60.5%, p = 0.005). No significant differences were observed between children with Down syndrome and those with other chronic conditions in severe disease (30.8% vs 40.6%, p = 0.397), mechanical ventilation (23.1% vs 29.1%, p = 0.760), or length of hospital stay (median 6 vs 7 days, p = 0.148). Overall, three-group comparisons demonstrated significant differences in oxygen requirement (p < 0.001) and length of stay (p < 0.001). Conclusion Children with Down syndrome hospitalized with pneumonia require oxygen supplementation more frequently than previously healthy children; however, their overall clinical course closely resembles that of children with other chronic underlying conditions. These findings suggest that medical complexity, rather than Down syndrome alone, is a key determinant of pneumonia outcomes.