OBJECTIVES: Previous studies have shown that only a small number of pediatric and young adult patients discontinue pump therapy, but risk factors for discontinuation are unclear. Aim of this study was to identify characteristics of pediatric and young adult patients with pump therapy which are associated with discontinuation of treatment. METHODS: Retrospective cohort study using a representative nationwide database (LRx; IMS Health) in Germany covering >80% of all prescriptions to members of statutory health insurances in 2008-2011. All patients (age groups: <6, 6-<12, 12-<18, 18-<25 years) with new prescriptions of insulin pumps or related material were identified (2009-2011) and were followed for ≥12 months. RESULTS: Overall, 3057 new pump users were identified, of whom 177 (5.8%) switched to other forms of insulin therapy within 12 months. Discontinuation was lowest in the age group <6 years (2.1%) and was highest in adolescents (12-<18 years: 7.5%) (p<0.01). In age-adjusted logistic regression, usage of steel needles (Odds ratio, OR, 95%CI: 1.69; 1.20-2.44) and prescriptions of antiepileptics (3.14; 1.49-6.59) were related to pump discontinuation. In younger age groups only, discontinuation was significantly higher in patients with thyroid therapy as a surrogate measure for thyroid autoimmunity (<6 years: 14.3%; 6-<12 years: 25.0%) (p<0.01). CONCLUSIONS: About 94% of pediatric and young adult patients maintained insulin pump therapy within 12 months. Adolescence (12-18 years), usage of steel needles and prescriptions of antiepiletic drugs are independent predictors of discontinuation. In younger age groups (<12 years) also thyroid therapy (indicating autoimmunity) was related to a higher risk of discontinuation.