An ACBRD publication using the Diabetes MILES – Australia dataset looks into awareness of hypoglycaemia among adults with type 1 diabetes
By Sienna Russell-Green
Severe hypoglycaemia (very low blood glucose, requiring assistance from another person for recovery) is one of the most common, feared and challenging complications of type 1 diabetes (T1D). Its symptoms are broad, and differ for each individual. Over time, with increasing duration of insulin therapy, the profile of these symptoms may change, and their intensity reduce, which can lead to impaired awareness of hypoglycemia (IAH). Timely recognition, treatment and avoidance of severe episodes can be improved through self-monitoring of blood glucose (SMBG).
The aim of this study led by Dr Christel Hendrieckx was to: a) investigate rates of severe hypoglycemia and IAH in a large Australian cohort, and b) assess awareness and symptoms of hypoglycemia, and their associations with SMBG. Data were analysed from the Diabetes MILES – Australia Study, a large national survey about what it is like to live with type 1 or type 2 diabetes (see methods paper). For the current study, data from 642 participants with T1D were used. They had a mean age of 41±13 years and a mean diabetes duration of 15±13 years. The Hypoglycemia Awareness Questionnaire (HypoA-Q) and the Gold Score were used to evaluate hypoglycemia events and IAH. Three study-specific items regarding SMBG practices were also included.
In this cohort, 21% experienced ≥1 severe hypoglycemic events in the past six months, and 21% reported having IAH. Severe hypoglycaemic events were 4 times as likely in adults with IAH compared to those with intact awareness (1.4±3.9 vs 0.3±1.0). Those with IAH recognised hypoglycaemic symptoms at lower glucose levels compared to those with intact awareness. In the IAH group, 30% reported autonomic symptoms (e.g. trembling, hunger, sweating) at glucose levels ≤2.5mmol/L, and 8% reported no symptoms at all. In contrast, 47% of those with intact awareness recognised autonomic symptoms before their glucose level dropped ≤3.5mmol/L. Most individuals with IAH still experienced autonomic and/or neuroglycopenic symptoms (e.g. confusion, difficult concentrating/speaking), although at significantly lower thresholds than those with intact awareness.
Importantly, those with IAH checked their blood glucose more frequently than those without. Those with IAH performing SMBG at least 4 times per day reported more hypoglycemic events in the past week. They were more likely to treat hypoglycaemia at a higher glucose level (≥3.5mmol/L) than those checking their blood glucose <4 times per day.
This study supports international findings, identifying that total loss of hypoglycemia symptoms is rare; many people with IAH still experience symptoms, albeit at a lower glucose threshold. In addition, frequent SMBG aids in early recognition and treatment of hypoglycaemia. Further investigation is needed to restore hypoglycaemic awareness and prevent severe hypoglycaemia in this population.
If you are interested in finding out more about hypoglycaemia, check out our other blog posts.
Hendrieckx C, Hagger V, Jenkins A, Skinner TC, Pouwer F & Speight J. Severe hypoglycemia, impaired awareness of hypoglycemia, and self-monitoring in adults with type 1 diabetes: Results from Diabetes MILES- Australia. Journal of Diabetes and Its Complications, 2017; 31 (3): 577 – 582 doi: 10.1016/j.jdiacomp.2016.11.013.Print This Post