Severe hypoglycemia, impaired awareness of hypoglycemia, and self-monitoring in adults with type 1 diabetes: Results from Diabetes MILES-Australia.

Aims: To assess prevalence of severe hypoglycemia, awareness and symptoms of hypoglycemia, and their associations with self-monitoring of blood glucose.

Methods: Diabetes MILES-Australia Study participants completed validated questionnaires and study-specific items.

Results: Of 642 adults with type 1 diabetes, 21% reported ≥1 severe hypoglycemic event in the past six months, and 21% reported impaired awareness of hypoglycemia (IAH). Severe hypoglycemia was increased four-fold for those with IAH compared with intact awareness (1.4±3.9 versus 0.3±1.0). Of those with IAH, 92% perceived autonomic and 88% neuroglycopenic symptoms, albeit at lower glucose thresholds compared to people with intact awareness. Those with IAH were more likely to perceive both symptom types at the same glucose level or to perceive neuroglycopenic symptoms first (all p<0.001). Eighteen percent with IAH treated hypoglycemia only when they perceived symptoms and another 18% only when their capillary glucose was <3.0mmol/L.

Conclusions: One in five adults with type 1 diabetes had IAH or experienced severe hypoglycemia in the past sixmonths. Total loss of hypoglycemia symptoms was rare; most people with IAH retained autonomic symptoms, perceived at relatively low glucose levels. Frequent self-monitoring of blood glucose prompted early recognition and treatment of hypoglycemia, suggesting severe hypoglycemia risk can be minimized.