Abstract
AIMS: Level 3 (severe) hypoglycaemia is a serious, yet preventable, complication of insulin- or secretagogue-treated diabetes. However, real-world insight into its incidence and risk factors remains limited. We analysed data from the iNPHORM study to address this gap. MATERIALS AND METHODS: iNPHORM is a prospective internet panel survey of US adults (aged 18-90) with type 1 diabetes (T1D) or insulin- and/or secretagogue-treated type 2 diabetes (T2D). A screener, baseline and 12-monthly follow-up questionnaires captured data on Level 3 hypoglycaemia and participant characteristics. Crude incidence proportions and annualized event rates were calculated. Repeated LASSO selection and negative binomial regression identified risk factors, with separate models for T1D and T2D. RESULTS: Among 985 participants (T1D: 16.7%), 35.0% experienced ≥1 Level 3 event over follow-up (T1D: 45.0%; T2D: 33.0%). The annualized rate was 4.98 EPPY (T1D: 3.56; T2D: 5.26). In T1D, rates were higher among individuals identifying as non-White (RR [rate ratio]: 2.03), with prior diabetes ketoacidosis (RR: 6.49), and greater fear of hypoglycaemia (RR: 1.41). Prior diabetes education (RR: 0.42) was protective. In T2D, rates were higher with younger age (RR: 0.77 per 10-year increase), greater fear of hypoglycaemia (RR: 1.18), more diabetes complications, higher secretagogue dose, more diabetes visits (RR: 1.72), longer use of continuous/flash glucose monitoring, impaired awareness of hypoglycaemia and a greater number of past healthcare-requiring severe hypoglycaemia (RR: 1.12). CONCLUSIONS: Level 3 hypoglycaemia remains common in T1D and T2D. Findings support risk-targeted prevention and diabetes care strategies that co-prioritize safety and effectiveness.