Evaluating Transition and Survival in Adolescents and Young Adults with Inborn Errors of Immunity

Background Despite advancements in early diagnosis and treatment of patients with inborn errors of immunity (IEI), transitioning from pediatric to adult care remains challenging, with significant barriers contributing to patients being lost to follow-up (LTF). This study evaluates risk factors for LTF and associated mortality. Methods We retrospectively identified IEI patients ≥19 years old at a tertiary care center who were previously followed in pediatric immunology. Patients were categorized as “Transitioned” (documented immunology follow-up ≥1 year after pediatric care) or “Lost to Follow-Up.” Variables included demographics, diagnosis, comorbidities, insurance type, and mortality. Associations with LTF and death were analyzed using univariate and multivariable logistic regression. Results Of 137 patients, 72.3% (n=99) transitioned successfully, while 27.7% (n=38) were LTF. Patients with ≥3 comorbidities were more likely to remain in care (OR 4.3, p<0.001). Cardiovascular and musculoskeletal comorbidities were each independently associated with successful transition in both univariate and multivariable models (p<0.05). Demographic variables, diagnosis, and insurance type were not significantly associated with LTF. Eighteen patients (13.1%) died, with a mean age at death of 25.8 years (range 19–40), notably higher than expected for this age group. Mortality was significantly associated with ≥3 comorbidities (OR for death 3.45, p=0.038), cardiovascular (OR 3.7, p=0.011), and respiratory comorbidities (OR 3.0, p=0.047). In adjusted analysis, cardiovascular comorbidity remained a significant predictor of death (OR 4.5, p=0.012). Public insurance was associated with a trend toward increased mortality (OR 2.86, p=0.053).Conclusions: Patients with multi-organ involvement were more likely to remain in care but also faced higher odds of death, highlighting the complex intersection of disease severity and healthcare engagement. The elevated mortality rate and trend toward worse outcomes among those with public insurance underscore the need for proactive, structured transition planning and policies that support equitable, continuous care for young adults with IEI.