Multisystem burden of neurofibromatosis 1 in Denmark: registry- and population-based rates of hospitalizations over the life span

Purpose: The aim was to assess lifetime risk for hospitalization in individuals with neurofibromatosis 1 (NF1). Methods: The 2467 individuals discharged with a diagnosis indicating NF1 or followed in a clinical center for NF1 were matched to 20,132 general population comparisons. Based on diagnoses in 12 main diagnostic groups and 146 subcategories, we calculated rate ratios (RRs), absolute excess risks (AERs), and hazard ratios for hospitalizations. Results: The RR for any first hospitalization among individuals with NF1 was 2.3 (95% confidence interval 2.2–2.5). A high AER was seen for all 12 main diagnostic groups, dominated by disorders of the nervous system (14.5% of all AERs), benign (13.6%) and malignant neoplasms (13.4%), and disorders of the digestive (10.5%) and respiratory systems (10.3%). Neoplasms, nerve and peripheral ganglia disease, pneumonia, epilepsy, bone and joint disorders, and intestinal infections were major contributors to the excess disease burden caused by NF1. Individuals with NF1 had more hospitalizations and spent more days in hospital than the comparisons. The increased risk for any hospitalization was observed for both children and adults, with or without an associated cancer. Conclusion: NF1 causes an overall greater likelihood of hospitalization, with frequent and longer hospitalizations involving all organ systems throughout life.