Hypoglycemia Subtypes in Type 1 Diabetes: An Exploration of the Hypoglycemia Fear Survey-II

Objectives: The Hypoglycemia Fear Survey II (HFS-II) is a well-validated measure of fear of hypoglycemia in people with type 1 diabetes. The aim of this study was to explore the relationships between hypoglycemia worries, behaviors, and cognitive barriers to hypoglycemia avoidance and hypoglycemia awareness status, severe hypoglycemia, and HbA1c.

Research design and methods: Participants with type 1 diabetes (n=178), enriched for people at risk of severe hypoglycemia (49%), completed questionnaires assessing hypoglycemia fear (HFS-II), hyperglycemia avoidance (HAS), diabetes distress (PAID), and cognitive barriers to hypoglycemia avoidance (A2A). Exploratory factor analysis was applied to the HFS-II. Clusters based on HFS-II, A2A, Gold, HAS and PAID were sought using k-means clustering.

Results: Four HFS-II factors were identified: Sought Safety, Restricted Activity, Ran High and Worry. Whilst Sought Safety, Restricted Activity and Worry increased with progressively impaired awareness and recurrent severe hypoglycemia, Ran High did not. Cluster analysis outlined four clusters: two clusters with preserved hypoglycemia awareness were differentiated by low fear / low cognitive barriers to hypoglycemia avoidance (cluster 1), versus high fear and distress and increased Ran High behaviors (cluster 2). Two clusters with impaired hypoglycemia awareness were differentiated by low fear / high cognitive barriers (cluster 3), and high fear / low cognitive barriers (cluster 4).

Conclusion: This is the first study to define clusters of hypoglycemia experience by worry, behaviors, and cognitive barriers to hypoglycemia avoidance. The resulting subtypes may be important in understanding and treating problematic hypoglycemia.